CC_11192024_Exhibit_2_8b — Glendale City Council, November 19, 2024

Glendale Water and Power’s Plan to Increase
Solar Adoption and Develop Additional
Distributed Energy Resources
November 6, 2024
E3 Study Report
Eric Cutter, Partner
Jun Zhang, Senior Managing Consultant
Sierra Spencer, Managing Consultant
Fangxing Liu, Senior Consultant
Brendan Mahoney, Senior Consultant
Hannah Platter, Consultant
Parker Wild, Consultant
Lindsay Bertrand, Senior Managing Consultant
Exhibit 2
2 Table of ContentsExecutive SummaryIntroductionCommunity Outreach & EngagementE3 Analyses & Findings•DER Technical Potential & Market Segmentation in Glendale•Dispatchable Capacity and Demand Reduction Capacity•Customized Avoided Costs for GWP•Adoption and Impact Analysis•Cost and Benefit Analysis•Potential Program and Policy OptionsDiscussionAppendix Objective Assessment of Costs and BenefitsE3 presents a non-technical assessment of the costs of achieving GWP's clean energy goals. This assessment does not specify who will bear these costs but focuses on outlining the various costs, benefits, and perspectives covered in the report.Information for Decision-MakersThis report analyzes the adoption of various program portfolios and illustrates the trade-offs of different options. It provides essential information to enable community members, the City Council, and the Commission to make informed recommendations regarding the benefits, costs, and feasibility of alternative approaches to achieving GWP's clean energy goals and striking the right balance for the City.Program Design AlternativesThis report describes various program design alternatives rather than specific recommendations. Detailed technical analyses are included later in the report for those interested in the supporting data. 3 Energy EfficiencyElectric VehiclesCustomer-Sited SolarFlexible LoadsEnergy StorageDemand Response Glossary: Types of DERs (Distributed Energy Resources)
And More…
Load ReducingLoad ShiftingLoad Increasing
4 Glossary: Levels of DER PotentialÊTechnical Potential is a metric that quantifies the maximum generation or capacity available for a technology in each region and does not consider the economic or market viability.ÊEconomic Potential applies a cost-effectiveness screen to each measure; only cost-effective measures are included in the economic potential (usually from total resource cost or societal perspectives).ÊAchievable Potential refines technical and economic potential by applying customer participation rates that account for real-world constraints, policy levers, and the likelihood of adoption.

Not Technically FeasibleNot Cost-Effective
Not Technically FeasibleNot Achievable
Technical PotentialTheoretical maximum generation or capacity available Economic PotentialEconomically cost-effective according to specific criteria Achievable PotentialPractical estimate considering real-world barriers Not Technically Feasible
Not Cost-Effective
5 ÊACC: Avoided Cost CalculatorÊBESS: Battery Energy Storage SystemÊCAISO: California Independent System OperatorÊCEC: California Energy CommissionÊC&I: Commercial & IndustrialÊCPUC: California Public Utilities CommissionÊDR: Demand ResponseÊEE: Energy EfficiencyÊELCC: Effective Load Carrying CapabilityÊEV: Electric VehicleÊFL: Flexible Load ÊGWP: Glendale Water & PowerÊIOU: Investor-Owned UtilityÊLDEV: Light-Duty Electric VehicleÊLOLH: Loss of Load HoursÊLOLP: Loss of Load ProbabilityÊMF: Multi-FamilyÊPV: PhotovoltaicÊRA: Resource AdequacyÊSF: Single-FamilyÊV1G: Vehicle-to-Grid, one-way power flowÊV2G: Vehicle-to-Grid, two-way power flowÊVGI: Vehicle Grid Integration Glossary: Other Acronyms
Section 1Executive Summary

Introduction
8 ÊE3 is the largest consulting group focused on the clean energy transition in North AmericaÊE3 is a recognized thought leader on decarbonization and clean energy transition topicsÊE3 has four major practice areas covering energy systems from bulk grid to behind the meter Who is E3?
•Valuation of DERs•DER dispatch and asset optimization•Rate design•Grid modernization•Building electrification•Vehicle electrification •Integrated resource planning for electric systems: reliability and resource mix•Planning for utility and state RPS + GHG targets•Utility planning and procurement decisions DER / Electrification / RatesIntegrated System Planning Economy-wide energy systemsBulk grid power systemsGrid edge & behind-the-meter •Climate and energy policy analysis•Long-term energy & climate scenarios•Electrification and low-carbon fuels •Future of gas Climate Pathways / Policy Analysis
•Asset valuation and due diligence•Strategic advisory•Energy market price forecasting•Market design•Transmission planning Asset Valuation & Strategy

9 Introduction and Objectives
Category 1Develop Plan to Increase Solar and Energy Storage Penetration and Develop Additional Distributed Energy Resources (DERs) Category 2Dispatchable Capacity and Demand Reduction Calculation Category 3Cost-Benefit Analysis
10% of GWP customer solar and energy storage adoption by 2027Additional dispatchable and peak load reduction capacity of 100 MW City Council Resolution of August 2022
10 GWP partnered with E3 to create an equitable solar and energy storage adoption plan with input from the community, focusing on community outreach and ensuring that multifamily and rental properties are thoroughly incorporated into the plan.

Under direction from the City Council, Glendale Water & Power issued an RFP focusing on three key categories of analytical support Category 1Develop Plan to Increase Solar and Energy Storage Penetration and Develop Additional DERs Category 2Dispatchable Capacity and Demand Reduction CalculationCalculate the estimated dispatchable capacity and demand reduction that can be achieved through the plan developed in Category 1.

Category 3Cost-Benefit AnalysisComplete an analysis of the benefits and cost of the plan developed in Category 1, and the analysis must include:•Direct and indirect economic benefits and costs, as well as environmental, societal, and other noneconomic benefits and costs; and direct and indirect impacts to low- and moderate-income (LMI) households.•If the analysis concludes any negative impact, the consultant shall include program options to mitigate the impact.•If the analysis concludes that there are any negative impacts on LMI households, the consultant shall include program options to fully mitigate the impact.

Develop a plan to achieve the goal of having at least 10% of GWP customers adopt solar and energy storage systems by 2027, and to develop additional demand management measures, with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW by December 31, 2027.If the consultant concludes that date to be unattainable then a date identified soon thereafter. The plan must include policies and incentives designed to be sufficient to ensure customers will adopt solar and energy storage at a rate that achieves the adoption and capacity goals stated above. The plan must include an alternative approach with a mix of storage at customer sites and at GWP-controlled sites, rather than all storage being located at customer sites.

Potential Policies and IncentivesNet Energy Metering (NEM)Upfront RebatesFeed-In-Tariff (FIT) ProgramPerformance-Based IncentivesEquity Strategies & PoliciesCommunity Solar ProjectsEnergy EfficiencyDemand Reduction

11 E3’s analytical support focused on several research questions How can local solar and distributed energy resources be effective, economic, and equitable parts of GWP’s reliable, low-carbon resource portfolio? Encouraging Customer Adoption
Realizing Value for Grid & CommunityManaging Cost-Shift & Affordability Balancing Multiple Objectives

1. What is the potential for solar, energy storage, and other DER adoption in meeting the City Council's goals?2. If the goals are not currently achievable, when can they realistically be met?3. What policies and incentives are necessary to achieve the adoption and capacity goals and their cost/benefit implications?4. How can policies and incentives be tailored to address the needs of low-income customers, residents in heavily pollution-burdened areas, multifamily properties, and rental properties?5. What are the direct and indirect economic, environmental, societal, and other non-economic benefits and costs associated with solar, energy storage, and other DER adoption?6. What are the direct and indirect impacts on low- and moderate-income (LMI) households resulting from these policies and incentives? 12 ÊE3 submitted a proposed budget and scope of work that we felt most cost-effectively met Glendale’s objectives, but did not provide all the deliverables requested (slide 10).ÊIn response to input from the community and City Council, scope of work was shifted to increase emphasis on community outreach and the number of stakeholder meetings. The shift in scope included:•Reducing the level of effort for program design recommendations•Focusing on solar and storage and not evaluating other DERs in depth ÊE3 developed and recommended program options that would help the City achieve its goals in a more cost-effective and equitable manner than net energy metering (NEM) alone.

1. Develop Plan to Increase Solar and Storage AdoptionüIdentify market segments and potential for solar and storage adoptionüDevelop program design and incentive recommendationsüPerform community outreach and engagement2. Evaluate Dispatchable Capacity and Peak Load Reduction PotentialüSummarize program adoption potential and impactsüReview GWP Integrated Resource PlanüSummarize dispatchable capacity and peak load reduction potential3. Perform Cost-Benefit AnalysisüDevelop avoided costs for DERüPerform cost-benefit analysis Revised Scope of WorkRevised Scope of Work Completed by E3 13 E3 designed the following workflow to support the adoption plan development Estimation of DER potential from all market segments
Enhancement of avoided costs to reflect GWP system plans and characteristics Analysis of adoption scenarios to identify the feasibility of City Council targets and short-list the most promising and effective policy and program options Benefit cost analysis considering direct/indirect economic and non-energy benefits; outline cost and benefit implications of all possible adoption strategies and alternatives to inform GWP’s decision-making process Deep dive into program options to provide program recommendations that balance customer adoption, customer affordability, and achieving value for the whole Glendale community Utility Challenges and Opportunities
15 Role of Local Clean Energy Resources
GWP faces many challenges in transitioning to a cleaner grid, and local clean energy resources could provide significant support Glendale's Clean Energy Vision•60% RPS by 2030 (CA regulatory requirement)•100% Clean Energy by 2035 (Glendale goal)Transmission & Land Constraints•Procuring new renewables outside of the City•Procuring new renewables within the CityIntegrated Resource Plan (IRP) Planning Challenges•Integrating renewables, coal retirement, and hydrogen combustion turbine (CT) conversion•Maintaining system reliability Maintaining leadership in clean and renewable energy
Unlocking more local generation
Reducing fossil fuel generation (Grayson Repower, etc.) System Context and Challenges

16 Turning potential into adoption requires a multifaceted approach to ensure equitable solar and DER adoption in Glendale Community Outreach
Permitting, Interconnection, and Approval Rules & Process Program & Incentive Design
Equity Strategies
Additional DR, EV, and EE Strategies
Utilize modeling and scenario analysis to evaluate and identify effective, least-cost, and equitable strategies, along with improved and customized avoided cost valuation and cost-benefit analysis for GWP These are the prerequisites for encouraging more adoption – incorporate community inputs and E3/Willdan project experience and expertise Energy Efficiency
Customer-Sited SolarEnergy Storage
Electric Vehicles
Flexible LoadsDemand Response
17 Turning potential into adoption requires a multifaceted approach to ensure equitable solar and DER adoption in Glendale Community Outreach
Permitting, Interconnection, and Approval Rules & Process Program & Incentive Design
Equity Strategy
Demand Response, Electric Vehicles, and Energy Efficiency Utilize modeling and scenario analysis to evaluate and identify effective, least-cost, and equitable strategies, along with improved and customized avoided cost valuation and cost-benefit analysis for GWP .

These are the prerequisites for encouraging more adoption – incorporate community inputs and E3/Willdan project experience and expertise •Additional outreach on federal and state support (e.g., Inflation Reduction Act, Self-Generation Incentive Program, etc.)•Propose adoption programs that use mechanisms that customers intuitively understand•Comprehensive outreach and knowledge campaigns from GWP to inform and educate residents•Intelligible program design •Faster, easier, and scalable permitting, interconnection, and approval process •Additional incentive and program considerations for low- to moderate-income (LMI) customers, disadvantaged communities (DACs), and pollution-burdened areas•Balance expanding solar access with minimizing cost shifts to non-adopters via community solar, virtual solar, and financing programs •Analysis of adoption scenarios to identify the feasibility of City Council targets •Short-list the most effective policy and program options that move towards the targets with improved equity and lower costs•Provide policy and program option alternatives to guide the direction for effective program design •Provide program and incentive options to further promote other DER technologies Requires additional studyFocus of this reportFocus of this report Summary of Findings and Recommendations
19 ÊNEM compensation for customer-owned solar will increase GWP electric rates for all customers by 6% in 2030 ($0.02/kWh)ÊCustomer solar adoption under NEM is predominately by single-family homeownersÊCustomer-owned solar and storage under NEM provides limited peak capacity reduction•The effective capacity of solar and storage is less than 10% and 50% of the installed capacity, respectively Encouraging customer adoption of solar and storage must be balanced against other municipal utility objectives Encouraging Customer Adoption
Realizing Value for Grid & CommunityManaging Cost-Shift & Rate Affordability Under NEM, customer adoption of solar and storage provides limited grid value and increases rates for all customers 20 Findings: Achieving the adoption goals by 2027 is not feasibleAchieving a goal of 10% customer solar adoption by 2027 is not feasible. The goal is theoretically feasible by 2030 with a significant increase in utility costs and effort, but real-world barriers remain.Achieving a goal of 10% customer storage adoption in the near future is not feasible. Achieving a goal of 100 MW of reliable peak load reduction with DERs is not feasible.

Recommendations§Set an adoption goal in terms of MW of installed capacity rather than a percentage of customers.§Perform additional analyses of realistically achievable potentials for customer-owned, community, and utility-scale solar and storage.§Develop an integrated resource plan with the potential and MW targets for each resource type.

Industry studies suggest that achievable potential is 20%-40% of the technical potential.

21 Findings: Adoption of customer-owned solar and storage increases GWP rates The scenarios achieving 10% solar adoption would result in a projected net cost of $23-$45 million to GWP ratepayers from 2024 to 2027. §Implement a Net Billing Tariff to reduce the cost shift.§Develop and implement non-bypassable charges and fixed customer charges to reduce the cost shift.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement a Net Billing Tariff.

The resulting rate increase would be 6-11% by 2030, with a low- and moderate-income (LMI) customer monthly bill increase of $4-$6.

Recommendations
22 Findings: Current customer-owned solar and storage adoption is predominately by single-family homeowners above the median incomeCustomer solar adoption in Glendale to date is above 10% for single-family homes and below 1% for renters and LMI customers.84% of customer solar adoption is in households above the median income. 88% of customer solar adoption is by property owners.
90% of customer solar adoption is in single-family homes. §Allow lower cost community solar and storage to count towards achieving the adoption goal.§Evaluate virtual solar programs that renters and LMI customers can subscribe to.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement virtual solar programs.

Recommendations
23 Findings: Customer-owned solar and storage provides limited reliable peak capacity reduction §Implement TOU rates that encourage customer storage adoption and dispatch for peak capacity reductions.§Study and expand demand response, electric vehicle, energy efficiency, utility dispatchable DER, and other programs for peak load reductions.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement TOU rates and utility dispatchable DER.

The effective capacity of customer-owned solar is less than 10% of the installed capacity.

The effective capacity of customer-owned storage is less than 50% of the installed capacity.The maximum projected reliable peak load reduction from customer-owned solar and storage is 10 MW by 2027. When including other DERs such as demand response, managed electric vehicle charging, and energy efficiency, the maximum projected reliable peak load reduction is 44 MW by 2027.Recommendations

24 Findings: Additional costs not included in this study will be required §Evaluate Glendale-specific program elements that will be the most effective for increasing DER adoption by renter, LMI, and DAC customers.§Evaluate the cost and feasibility of necessary changes to GWP’s billing and metering systems.§Consider the cost of additional program overhead and customer outreach.

Achieving the 10% customer solar adoption goal by 2030 will require increasing the pace of annual adoption from 438 customers last year to over 1,000 customers per year.Community feedback requested enhanced customer outreach and support as well as a streamlined permitting process.Additional overhead and incentives will be needed to reach renters, LMI, and DAC customers that face larger barriers to solar and storage adoption. Changes to GWP billing and metering systems will be required.

Recommendations
Current Solar and Storage Adoption Status
26 ÊGlendale has 2,900 customer-sited solar systems totaling 28 MW, most of which are owner-occupied, single-family, non-LMI households. Solar penetration is currently at 3.25% and solar system installations in Glendale have been increasing every year, despite the end of the solar incentive program in 2022.

Glendale’s current solar and storage penetration pattern skews towards single-family, owner-occupied, and non-LMI households

0.0% 2.0% 4.0% 6.0% 8.0% 10.0%12.0%
SF
C&I
MF
Historical Solar Penetration (%)
Customer Sector

0.0% 2.0% 4.0% 6.0% 8.0% 10.0%
Own
Re ntOwnership

0.0%1.0%2.0%3.0%4.0%5.0%6.0%
LMI
Non-LMIIncome Level
Single family (SF) sector has noticeably higher customer solar penetration, followed by commercial & industrial (C&I) and multi-family (MF) sector Owner-occupied buildings have noticeably higher customer solar penetrationNon-LMI customers have noticeably higher customer solar penetration Adoption Level (% of Total GWP Electric Customers)
27 ÊGlendale has less than 200 customer-sited storage systems, totaling 3 MWh. Most of these systems are owner-occupied, single-family, non-LMI households, with just one large system from commercial customers and none from multi-family residences, reflecting adoption barriers for renter and LMI customers.

Glendale’s current solar and storage penetration pattern skews towards single-family, owner-occupied, and non-LMI households

0.0% 0.2% 0.4% 0.6% 0.8% 1.0%
C&I
MF
SF
Customer Sector

0.0% 0.1% 0.2% 0.3% 0.4% 0.5% 0.6%
Own
Re ntOwnership

ÊHigher income customers are more likely to adopt paired batteries. •California residents tend to adopt paired batteries at a higher rate than other states, with attachment rates ranging from 6%-19% across income levels.

Understanding the demographics of residential adopters in California provides crucial context for shaping GWP’s future in solar and storage Source: Lawrence Berkeley National Laboratory
32 Glendale's solar adopters have higher incomes than the county, state, and national averagesLBNL Income Demographics of GWP Solar Adopters: Raw Income, Area Median Income 18%*
* General pop. data (includes non-adopters) is less granular, so households with incomes > $200k are shown in green/blue Share of 2016-2022 Solar Adopters by IncomeShare of 2016-2022 Solar Adopters by County Area Median Income (AMI) Source: Lawrence Berkeley National Laboratory (LBNL)
Impact of Net Energy Metering (NEM) and Net Billing Tariff (NBT) on GWP Rates 34 Rate Increase
Compensation for rooftop solar increases retail rates for all GWP customers Utility Costs Not Avoided by Solar
Avoided by Utility-Scale Solar
Avoided by Customer Solar
Not Utility Costs
Utility Costs Avoided by Solar
NEM 1.0 Cost Shift
Solar Benefits
Environmental & Societal*
Energy, GHG, Some Capacity
Some Transmission & Distribution
NEM 1.0 Bill Savings
Rate Increase
Utility Costs Not Avoided by SolarUtility Costs Avoided by Solar NBT Cost Shift
NBT Bill Savings
*Also provided by lower cost community and utility-scale solar 35 California’s NEM Cost Shift and Solar Adoption Post NBT Source: https://www.californiadgstats.ca.gov/charts/
NEM PV Installations
Energy Storage Installations
Net Billing Tariff
36 Parking Lots
Landfill
Industrial
Municipal
High Desert
Agricultural
Scrubland
Multiple types of solar and storage installations are available for GWP , with different cost implications Customer-OwnedCommunityUtility- Scale
Residential
Commercial
Rooftop
Community
Utility-Scale
Counts Towards 10% Customer Adoption Goal
Lower-Cost Alternatives with Similar Environmental Benefits $/kW System Cost
•Hillside solar is not considered by GWP.•Community solar in practice can involve large rooftop installations as well. 37 Customer-owned solar and storage is more expensive; lower cost alternatives provide similar environmental benefits •Modeled Market Price (MMP) Benchmarks from NREL Q1 2023 Customer-OwnedSolar + Storage
CommunitySolar + Storage
Utility-ScaleSolar + Storage
$4,700
$2,900$2,10040%
120%
$/kW Cost
60%
38 Additional benefits for community and customer-owned solar over utility-scale solar exist, but do not outweigh the cost premium ÊRooftop Solar•All Benefits of Community Solar•Customer Reliability•Increased Home Value•Others ÊCommunity Solar•Transmission & Distribution (T&D) Investment Reduction•T&D Line Loss Reduction•Reduced Land Use Impacts•Local Reliability, Resilience•Local Jobs Customer-Owned
Community
Plus
Technical Potential Analysis
40 ÊRooftop Solar: 313 MWÊParking Canopy Solar: approx. 300 MWÊGround-Mounted Solar: approx. 27 MW Technical Potential of Rooftop, Parking Canopy, and Ground-Mounted Solar in the City of Glendale Rooftop Solar: 313Parking Canopy Solar: 300Ground-Mounted Solar: 27 Technical potential is a metric that quantifies the maximum generation or capacity available for a technology in a given region and does not consider the economic or market viability.Variations in the definition of technical potential and assumptions in filtering criteria may impact results substantially.

Rooftop solar technical potential for the entire City of Glendale, including city-owned properties 41 ÊGWP conducted site-specific analyses on over 100 city-owned properties for potential large-scale rooftop, parking canopy, and ground-mounted solar projects•Over 60 sites are deemed feasibleÊMost sites are filtered out due to their project size of less than 100 kW each and various other developmental constraints, for example:•Not solar ready•Solar not advised by property owners•Historical or community use•Pending roof, structural, reconstruction, ADA, and feeder upgradesÊGWP has identified 10-15 large city-owned sites for developing solar projects•Collectively 10 MW of solar capacity•Six projects approved for construction (5 MW) Achievable solar and storage potential for city-owned properties must account for additional real-world constraintsTechnical Potential of Rooftop, Parking Lot, and Ground-Mounted SolarTotal Analyzed16 MWSolar Ready10 MW 5 MW
•Additional sites evaluated after the initial round of solar site analysis were not included. 6 Sites
10-15 Sites
100+ Sites
Approved for Construction
42 Ê75% of total roof space (based on building footprint) is considered developable for rooftop solar•Accounts for setback factor required by LA County, as well as potential obstructions; based on research conducted for NREL’s LA100 studyÊSolar potential based on 110% of customer’s annual load•Assuming 20% capacity factor (DC), based on default system parameters from NREL’s PVWatts tool for Glendale•Module power density of 160 W/m2 (approximately 14.86 W/sq. ft.), in line with NREL REPLICA estimate for flat roofs ÊNumber of buildings suitable for solar adjusted to 79.25%•Based on Project Sunroof data for Glendale; accounts for factors such as structural stability of roof and electrical code complianceÊStorage potential aligns with maximum DER ratings allowed by GWP for solar and storage systems•Assume only customers with non-zero solar technical potential are considered eligible to install storage•Minimum storage potential is 30 kWh; if solar potential exceeds 10 kW, maximum storage potential of 110% of the historical average daily usage Rooftop Solar and Customer Battery Storage Technical Potential in Glendale (E3 Mid-Case) Note: These figures represent the theoretical maximum of solar and storage capacity under applicable policies and other constraints. In the adoption analysis, systems were sized based on customer needs. 95 MW30%5 kWdc/cust
86 MW27%2 kWdc/cust
132 MW42%18 kWdc/cust
For Mid-Case
Rooftop Solar Potential in Glendale
559 MWh63%29 kWh/cust
216 MWh24%4 kWh/cust
115 MWh13%15 kWh/cust For Mid-Case
Battery Storage Potential in Glendale
43 Single-FamilyMulti-FamilyCommercial & Industrial
For Mid-Case, in MWSolar Potential by Sector, Ownership Status, and Building Type E3 estimates identify 313 MW GWP solar potential from all market segments (E3 Mid-Case) * Omits sites that could not be categorized
Key Observations•Single-Family: Owner-occupied single-family residences show the greatest potential for adoption. •Multi-Family: Multi-family rental properties follow closely behind but face challenges due to ownership dynamics and split incentives between owners and tenants. Addressing these issues could unlock significant potential. •Commercial & Industrial: While comprising fewer customers, these sectors have larger average installation sizes, making them significant contributors to achieving the 100 MW DER capacity target. 44 Single-FamilyMulti-FamilyCommercial & Industrial
For Mid-Case, in MWhStorage Potential by Sector, Ownership Status, and Building Type E3 estimates identify 900 MWh GWP storage potential from all market segments (E3 Mid-Case) * Omits sites that could not be categorized
Key Observations•Single-Family: Owner-occupied single-family residences show the greatest potential for adoption. Customers with less than 10 kW solar systems can install up to 30 kWh battery storage systems.•Multi-Family: Multi-family rental properties follow closely behind but face challenges due to ownership dynamics and split incentives between owners and tenants. Addressing these issues could unlock significant potential.•Commercial & Industrial: For large solar systems (>10 kW), maximum storage potential is up to 110% of the historical average daily usage, which constrains the potential from the C&I sectors.

Scenario Overview
46 Scenario 1: Continue NEMScenario 2: Targeted LMI/DACs & MF AdoptionScenario 3: BalancedScenario 4: Widespread Adoption E3 evaluated four program scenarios to identify target feasibility and show trade-offs in adoption, equity, and costsNEM CompensationAdditional IncentivesAccess for Renter and LMI CustomersProvide More Utility Support Program & Incentive Design
Address Additional Barriers•Low and Moderate Income (LMI)•Disadvantaged Communities (DACs)•Multi-family (MF) 47 Other Utility Support
The scenarios outline different pathways towards Glendale’s DER adoption targetNEM CompensationAdditional Incentives*Renter and LMI Customer Barriers S1S2Targeted LMI MF Adoption
S3Balanced
S4Widespread Adoption
S5Direct Install
Net energy metering at retail ratesNet energy billing at avoided costs Net energy metering at retail rates
Net energy metering at retail rates
Net energy billing above avoided costs but below retail rates Federal and stateFederal and state, utility direct install for LMI/DAC MF customers Federal and state, and direct install for MF renter LMI/DAC customers Federal and state, 5-yr payback utility incentive for all MF customers Federal and state, 7-yr payback utility incentive for LMI/DAC MF buildings Persist
Optimistic outlook on enhanced community outreach and support, along with improved permitting processes starting early 2025 Optimistic outlook for providing renter and LMI customer solutions starting early 2025 S0Business as UsualNet energy metering at retail ratesFederal and statePersistAt the Current Level PersistAt the Current Level
Evaluate Adoption StrategiesReferenceHypothetical Feasibility *Additional incentives is a general representation of all types of incentives including potential upfront incentives and performance-based incentives offered by GWP. Assuming receipt of GWP incentives requires customers dispatch battery storage against utility signals to maximize community benefits.

Continue Current NEM
48 Possible InterpretationsÊEligible systems include customer-sited solar, solar + storage, and/or standalone storage systemsÊAchieve the resolution by December 31st, 2027ÊEligible GWP electric customer adoption includes:1.Rooftop solar owned, financed, or leased by single-family and commercial & industrial customers (one system for one electric customer)2.Rooftop solar owned, financed, or leased by multi-family property owners/managers and commercial & industrial customers under virtual solar programs and shared among tenants and unit owners (one system for multiple electric customers)3.Subscribers of off-site solar solutions like community solar, solar share, and green rate options (one project for numerous electric customers) Possible InterpretationsÊAchieve the resolution by December 31st, 2027ÊEligible demand management measures include solar, storage, electric vehicles, energy efficiency, and/or demand response (both load shedding and load shifting)ÊFocused on additional measures and exclude existing capacity ÊPeak dispatchable capacity: battery storage and EVs with bidirectional charging/discharging capability (V2G)ÊPeak load-reducing capacity: solar, EV managed charging (V1G), energy efficiency, and demand response which either shave load during peak periods or shift load to off-peak periodsÊCapacity measured by nameplate capacity or effective capacity (kW) How we interpret the City Council’s resolution is importantIn August 2022, the Glendale City Council passed a resolution expressing their intent to adopt policies and practices aimed at achieving the goal of having at least 10% of GWP customers adopt solar and energy storage systems by 2027, and to develop additional demand management measures with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW.At least 10% of GWP customers adopt solar and energy storage systems by 2027 Develop additional demand management measures, with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW Expanded Eligibility Criteria •In general, Effective Capacity = Nameplate Capacity * ELCC•Effective Load Carrying Capability (ELCC) measures a resource's contribution to reliability based on the incremental quantity of load that can be satisfied by adding the resource to the grid Key Clarification Question: Which systems qualify for the 10% adoption target? Standalone SolarSolar + StorageStandalone Storage
Key Clarification Question: 100 MW nameplate or effective capacity?Nameplate CapacityEffective CapacityVS. 49 ÊProgram proposals ranked by overall qualitative performanceÊReasonable DER compensation levels that mitigate cost shifts are preferred Qualitative screening analysis prioritizes program and policy options crucial for achieving City Council targets over othersPriority Level

Detailed Scenario Analysis
51 ÊScenarios are shaped by stakeholder inputs, policy directions, and the balancing of multiple GWP objectives.ÊEach proposed program portfolio should be evaluated based on its effectiveness in addressing these values from various perspectives.

The performance of each scenario should be comprehensively evaluated using different metrics to assess adoption, equity, and costs Encouraging Customer Adoption
Realizing Value for Grid & CommunityManaging Cost-Shift & Affordability Balancing Multiple Objectives
AdoptionRatepayer ImpactRate & Bill Impact
Distributional Equity ImpactOthers
Key Scenario Performance Metrics
52 Adoption scenarios project theoretical upper bounds for adoption, resulting in net ratepayer costs and rate impacts 0%
5%
10%
15%
20%
25%
30%
2024
2025
2026
2027
2028
2029
2030
0%
5%
10%
15%
20%
25%
30%
2024
2025
2026
2027
2028
2029
2030
•The adoption scenarios project upper bounds for solar adoption by 2027. The adoption level results will be further limited by implementation barriers, customer adoption behavior, and other financial and non-economic barriers that customers face.•All proposed strategies impose more costs on GWP ratepayers and lead to further increases in retail rates.•There are alternatives to current NEM that can still promote local solar and storage but also reduce costs to GWP ratepayers.

Reference Scenario (S0)Range of Scenario Results (S1-S4) Solar Adoption (%)Storage Adoption (%)Net Ratepayer Costs ($)Rate Impacts (¢/kWh)CumulativeCumulativeAnnualCompared with rates w/o post-2023 solar and storage Continue Current NEM (S1)
On top of other sources of anticipated rate growthYear
53 ÊScenarios are shaped by stakeholder input, policy directives, and GWP’s goals. Each scenario’s proposed program portfolio was evaluated based on how effectively it addresses these values from various perspectives.ÊContinuing the current NEM structure may lead to higher costs. However, a strategically planned program and incentive portfolio could drive greater solar and storage adoption, improve distributional equity, and reduce ratepayers' costs.

Metrics of Success by Adoption Scenario
GWP ImpactsDistributional Equity ImpactsSolar Adopter ImpactsNet Economic Societal BenefitMinimize Cost ShiftReduction of GHG ImpactsEase of ImplementationLMI Customer AdoptionIncreased AdoptionAdopter Financial ValueRenter Adoption S1Continue Current NEMS2Targeted LMI MF Adoption
S3Balanced
S4Widespread Adoption
Mid
HighHighHighHigh
Very HighVery High
Very HighLowLowHighHigh
HighHighVery Low
HighHigh
HighHighLowHighHighMidVery Low
Low
Mid
Very Low
Mid
HighHigh
Very High
Societal and Ratepayer Impacts
Low
Customer Adoption Projections
55 2027 Customer Adoption by Scenario – SolarIncluding solar-only and solar + storage systems, cumulative adoption by 2027 S1: Continue Current NEMS2: Targeted MF LMI AdoptionS3: BalancedS4: Widespread Adoption LMI: Low and Moderate IncomeMF: Multi-family
10%
12% 12%
16%
2%
5%
4%
6%
1%
5%
5%
8%
1%
6% 5%
8%
0%
2%
4%
6%
8%
10%
12%
14%
16%
18%
S1 S2 S3 S4
Total and LMI Adoption in 2027 Relative to All GWP Customers (%) Total Adoption
LMI Adoption
MF Adoption
Renter Adoption
% of Total GWP Customers

9.6%

11.7% 11.8%

15.8%

1.6%

4.9% 4.4%

6.3%

1.0%

5.1% 4.8%

8.0%

0.9%

5.3% 5.1%

8.2%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

16.0%
S1 S2 S3 S4
Adoption in 2027 Relative to All GWP Customers (%)
Total Adoption
LMI Adoption
MF Adoption
Renter Adoption
% of Total GWP Customers
Adoption Scenarios
Solar Adoption (% of Total GWP Electric Customers)
56 2027 Customer Adoption by Scenario – Battery StorageIncluding solar + storage systems, cumulative adoption by 2027 LMI: Low and Moderate IncomeMF: Multi-family

1.5%

2.7% 2.1% 2.0%

0.3%

1.4% 1.1% 1.0%

0.2%

1.5% 1.2% 1.4%

0.3%

1.5% 1.2% 1.4%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

16.0%
S1 S2 S3 S4
Adoption in 2027 Relative to All GWP Customers (%)
Total Adoption
LMI Adoption
MF Adoption
Renter Adoption
% of Total GWP Customers

1.5%

2.7%

2.1% 2.0%

0.3%

1.4% 1.1% 1.0%

0.2%

1.5% 1.2% 1.4%

0.3%

1.5% 1.2% 1.4%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

NEM CompensationAdditional IncentivesAccess for Renter and LMI CustomersProvide More Utility Support Program & Incentive Design
Address Additional Barriers
Adoption Scenarios
Economic Analysis: Scenario Comparison
59 ÊThe CPUC defines “cost-effective” and “cost-effectiveness” as a set of well-defined “cost tests in the California Standard Practice Manual (SPM)”*ÊThese cost tests provide a methodological framework to examine the benefits and costs of a particular measure from different perspectives and have become a standard in many other jurisdictions Cost-Effectiveness and Cost Test Perspectives
Cost Test Primary QuestionPCTParticipant Cost TestNet benefit for customers who adopt solar?RIMRatepayer Impact MeasureWill utility rates increase or decrease?PACTProgram Administrator Cost TestWill utility costs increase or decrease?TRCTotal Resource Cost TestNet benefits to City of Glendale?SCTSocietal Cost TestNet benefit to society as a whole?* California Standard Practice Manual 60 Benefits and Costs Components by Cost Test Perspective ComponentParticipant Cost Test (PCT)Ratepayer Impact Measure (RIM)Societal Cost Test (SCT)Bill Savings+–Upfront Costs– –Fixed Operations and Maintenance Costs– –Federal and State Incentives+ +GWP Incentives+–Utility Avoided Costs++Resiliency Benefits+Additional Societal Benefits + N/ACostBenefitNote: Administrative costs were not included in the cost tests. When interpreting the results, please consider these additional costs from both the ratepayer and administrator perspectives to ensure that all program implementation expenses are fully accounted for.

Encouraging Customer Adoption
Realizing Value for Grid & CommunityManaging Cost-Shift & Affordability Participant Cost Test
Ratepayer Cost TestSocietal Cost Test
61 Economic Analysis of Scenarios: Cost Test Scores
S1Continue Current NEMS2Targeted LMI/MF AdoptionS3BalancedS4Widespread Adoption Participant Cost Test

2.252.163.04

3.04 Ratepayer Impact Measure

0.280.450.390.29
Societal Cost Test

1.872.092.112.17
𝐵𝑒𝑛𝑒𝑓𝑖𝑡𝑠𝐶𝑜𝑠𝑡𝑠≥1.0
62 ÊAll scenarios have annual net ratepayer costs that increase GWP rates due to accelerating DER adoptionAnnual Net Ratepayer Costs $-
$20
$40
$60
$80
$100
$120
2024
2026
2028
2030
2032
2034
2036
2038
2040
2042
2044
2046
2048
2050
2052
2054
Millions
S1 Net Ratepayer Costs
S2 Net Ratepayer Costs
S3 Net Ratepayer Costs
S4 Net Ratepayer Costs
$-
$20
$40
$60
$80
$100
$120
2024
2026
2028
2030
2032
2034
2036
2038
2040
2042
2044
2046
2048
2050
2052
2054
Millions
S1 Net Ratepayer Costs
S2 Net Ratepayer Costs
S3 Net Ratepayer Costs
S4 Net Ratepayer Costs
S4
S2S3S1
63 Key Takeaways: Cost and Benefit AnalysisParticipant Perspective•In all scenarios, solar and solar + storage provide net benefits over the system's lifetime•Net benefits are driven by high bill savings under various billing mechanisms, even under net billing•Despite lifetime savings, high upfront costs of solar and solar + storage may still pose barriers to adoption SocietalPerspective•Solar and solar + storage provide net benefits to society across all scenarios Ratepayer Perspective•All adoption scenarios have net ratepayer costs, meaning compensation provided to solar and solar + storage customers higher than the cost savings for GWP•A strategically planned program and incentive portfolio can achieve higher solar and storage adoption with lower impacts on GWP ratepayers

Findings and Recommendations
65 Clarifications on how to correctly interpret the City Council’s adoption targets are necessaryAt least 10% of GWP customers adopt solar and energy storage systems by 202710% adoption target for solar + storage systems vs. 10% for either solar or solar + storage systems? Develop additional demand management measures, with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW Which systems qualify?
Standalone SolarSolar + StorageStandalone Storage
100 MW nameplate or effective capacity?
Nameplate CapacityEffective CapacityVS.
66 Findings: Achieving the adoption goals by 2027 is not feasibleAchieving a goal of 10% customer solar adoption by 2027 is not feasible. The goal is theoretically feasible by 2030 with a significant increase in utility costs and effort, but real-world barriers remain.Achieving a goal of 10% customer storage adoption in the near future is not feasible. Achieving a goal of 100 MW of reliable peak load reduction with DERs is not feasible.

Industry studies suggest that achievable potential is 20%-40% of the technical potential.

67 Findings: Adoption of customer-owned solar and storage increases GWP rates The scenarios achieving 10% solar adoption would result in a projected net cost of $23-$45 million to GWP ratepayers from 2024 to 2027. §Implement a Net Billing Tariff to reduce the cost shift.§Develop and implement non-bypassable charges and fixed customer charges to reduce the cost shift.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement a Net Billing Tariff.

The resulting rate increase would be 6-11% by 2030, with a low- and moderate-income (LMI) customer monthly bill increase of $4-$6.

Recommendations
68 Findings: Current customer-owned solar and storage adoption is predominately by single-family homeowners above the median incomeCustomer solar adoption in Glendale to date is above 10% for single-family homes and below 1% for renters and LMI customers.84% of customer solar adoption is in households above the median income. 88% of customer solar adoption is by property owners.
90% of customer solar adoption is in single-family homes. §Allow lower cost community solar and storage to count towards achieving the adoption goal.§Evaluate virtual solar programs that renters and LMI customers can subscribe to.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement virtual solar programs.

Recommendations
69 Findings: Customer-owned solar and storage provides limited reliable peak capacity reduction §Implement TOU rates that encourage customer storage adoption and dispatch for peak capacity reductions.§Study and expand demand response, electric vehicle, energy efficiency, utility dispatchable DER, and other programs for peak load reductions.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement TOU rates and utility dispatchable DER.

The effective capacity of customer-owned solar is less than 10% of the installed capacity.

70 Findings: Additional costs not included in this study will be required §Evaluate Glendale-specific program elements that will be the most effective for increasing DER adoption by renter, LMI, and DAC customers.§Evaluate the cost and feasibility of necessary changes to GWP’s billing and metering systems.§Consider the cost of additional program overhead and customer outreach.

Recommendations
71 Options for Program Improvements: Rooftop Solar Compensation Compensation RatesShift solar and storage compensation to a net billing tariff structure.Align export compensation with GWP avoided costs.Require TOU rates for solar and storage program enrollment.

Program Sizing ConstraintsExpand total program size by allowing more customers to be subscribed to the customer generation tariff.Relax constraints on system sizing.

Retail Rate Reform for All CustomersPromote or mandate a switch from flat rates to TOU rates.Consider non-bypassable and fixed charges to minimize cost shifts.Align TOU rate peak and off-peak periods with underlying system costs. 72 Options for Program Improvements: Feed-in-Tariff
Program Sizing ConstraintsExpand total program size beyond 4.2 MW. Remove the 1.4 MW constraint on system sizing.

Long-Term Rate GuaranteesConsider long-term rate guarantees. GWP’s current feed-in-tariff only locks in compensation for a single year, preventing developers from conducting economic analyses over the resource's lifetime.

Location-Specific IncentivesConsider incentivizing the usage of underutilized space for solar, including carports (parking canopies), landfills, and other large flat surfaces. This could be in the form of an adder to the feed-in-tariff or an upfront rebate.

Section 2Introduction

74 Who is E3? Thought Leadership, Fact Based, Trusted
San FranciscoNew YorkBoston
300+ projects per year across ourdiverse client base
130+ full-time consultantsEngineering, Economics, Mathematics, and Public Policy Degrees30+ years of deep expertise Calgary
Recent Examples of E3 ProjectsE3 ClientsMarket price forecasts for every U.S. market (wholesale and retail), supporting billions of dollars of capital deployment;Buy-side diligence support on several successful investments in electric utilities (~$15B in total);Assessment of east coast and west coast offshore wind opportunities (multiple clients);Hydrogen policy and market support for State of Colorado, Mitsubishi Americas, ACORE, and multiple developer and utility clients; Supporting investment in several stand-alone energy storage platforms and individual assets across North America (15+ GW | ~$5B);Evaluation of electric vehicle and V2G markets in North America for several large automakers;Supporting NYSERDA across Climate Leadership and Community Protection Act topics;Supporting investment in 5+ GW of community solar and distributed energy resource projects;Supporting several electric vehicle infrastructure and automakers with strategy.

Denver

75 ÊE3 is the largest consulting group focused on the clean energy transition in North AmericaÊE3 is a recognized thought leader on decarbonization and clean energy transition topicsÊE3 has four major practice areas covering energy systems from bulk grid to behind the meter Who is E3?
•Valuation of DERs•DER dispatch and asset optimization•Rate design•Grid modernization•Building electrification•Vehicle electrification •Integrated resource planning for electric systems: reliability and resource mix•Planning for utility and state RPS + GHG targets•Utility planning and procurement decisions DER / Electrification / RatesIntegrated System Planning Economy-wide energy systemsBulk grid power systemsGrid edge & behind-the-meter •Climate and energy policy analysis•Long-term energy & climate scenarios•Electrification and low-carbon fuels •Future of gas Climate Pathways / Policy Analysis
•Asset valuation and due diligence•Strategic advisory•Energy market price forecasting•Market design•Transmission planning Asset Valuation & Strategy

76 E3’s comprehensive modeling toolkit positions E3 well to study future energy system dynamicsHourly simulations of electric loads for specific end usesDetailed operational simulations of system dispatch and flexibility needsEconomy-wide accounting of energy supplies and demands under deep decarbonization scenarios Loss of load probability simulation to measure resource adequacy RESHAPE & EVGridProduction Simulation(AuroraXMP and PLEXOS)PATHWAYS RECAP
Optimal capacity expansion model for electric systems

RESOLVE
Hour of Day123456789101112131415161718192021222324JanFebMarAprMayJunJulAugSepOctNovDec2018 Loss of Load High LOLP occurs in summer evenings when load is high but solar output declines 2018Loss of Load Probability
Hourly electrification loads during a three-day cold snap Hour of Day
Dynamic operating reserves for renewable integration

RESERVE
Economy-wide energy systemsBulk grid power systemsGrid edge & behind-the-meter Low-Carbon Fuels and Future of Gas
Fuel Cost
Fuel Supply
Role of fuels in deep decarbonizationDER Toolkit for optimizing DER value stacking opportunities and adoption

RESTORE & IDSM
77 Context & BackgroundÊGlendale has set ambitious clean energy goals to establish itself as a leader in clean energy and is committed to maintaining its position as a leader in local clean and renewable energyÊGrayson Repowering Project & Pursuit of Cleaner Alternatives:•Glendale approved the Grayson Repowering Project, including environmentally superior alternatives.•Project Alternative 7 features five reciprocating internal combustion engines (RICEs) totaling 93 MW and 75 MW/300 MWh energy storage systems.•Glendale seeks cleaner alternatives to minimize the need for RICEs.ÊRooftop Solar and Battery Storage:•Glendale aims to enhance residents' rooftop solar access and encourage additional installations.•Battery storage, located at customer or city sites, will provide significant local clean energy resources.•Glendale recognizes load growth from electrification and seeks to evaluate the co-benefits of solar and storage systems with electrification efforts.ÊDemand Reduction and Load Shifting:•Glendale plans to reduce electricity demand and shift energy use to off-peak hours, enhancing system reliability.

City Council ResolutionÊGlendale intends to:•Maximize the use of clean and renewable energy to serve the community.•Achieve 100% clean energy by 2035.ÊThe Glendale City Council passed a resolution expressing their intent to adopt policies and practices aimed at:•Achieving the goal of having at least 10% of GWP customers adopt solar and energy storage systems by 2027.•Developing additional demand management measures, with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW.ÊStaff is directed to:•Engage with a consultant to develop the adoption plan.•Calculate the estimated dispatchable capacity and demand reduction.•Determine the benefits and costs of the plan, including direct/indirect economic, environmental, societal, and other non-economic benefits and costs.

Glendale’s City Council resolution outlines its clean energy commitment 78 GWP partnered with E3 to create an equitable solar and energy storage adoption plan with input from the community, focusing on community outreach and ensuring that multifamily and rental properties are thoroughly incorporated into the plan.

79 ÊE3 submitted a proposed budget and scope of work that we felt most cost-effectively met Glendale’s objectives, but did provide all the deliverables requested in the RFP .ÊIn response to input from the community and City Council, proposed work was shifted to increase emphasis on community outreach and the number of stakeholder meetings, with no increase in the overall budget. The shift in scope included:•Reducing the level of effort for program design recommendations•Focusing on solar and storage and not evaluating other DER in depth ÊE3 developed and recommended program options that would help the City achieve its goals in a more cost-effective and equitable manner than net energy metering (NEM) alone.

1. What is the potential for solar, energy storage, and other DER adoption in meeting the City Council's goals?2. If the goals are not currently achievable, when can they realistically be met?3. What policies and incentives are necessary to achieve the adoption and capacity goals and their cost/benefit implications?4. How can policies and incentives be tailored to address the needs of low-income customers, residents in heavily pollution-burdened areas, multifamily properties, and rental properties?5. What are the direct and indirect economic, environmental, societal, and other non-economic benefits and costs associated with solar, energy storage, and other DER adoption?6. What are the direct and indirect impacts on low- and moderate-income (LMI) households resulting from these policies and incentives? 81 E3’s project leadership team drew expertise from across the firm with expert support from Willdan and Dakota Communications ADVISORYSUPPORTKEY PERSONNELJun ZhangSr. Mng. ConsultantProject Manager Sierra SpencerManaging ConsultantCost Benefit Lead
Patrick BurgessVice PresidentWilldan DER Lead
Eric CutterPartnerProject Lead
Ben Laboy, PESenior Project Engineer
Fangxing LiuSenior ConsultantDemand Impact Lead
Brendan MahoneySenior ConsultantProject Analyst
Hannah PlatterConsultantProject Analyst
Jonathan BatyAssociate Vice PresidentPrimary Engineer
Max DeLoachMarket Analyst
Rick TaylorPartnerOutreach Support Lead
Jad HagekhalilProject AssistantOutreach Support
Snuller PriceSenior PartnerSenior Advisor
Charlie DuffManaging ConsultantProject Advisor
Lindsay BertrandSr. Mng. ConsultantAsst. Project Manager Tara Katamay-SmithSenior ConsultantProject Advisor
Mike SontagAssociate DirectorProject Advisor
Category 1Category 2Category 3
*Dec 2023*Feb-Mar 2024
Parker WildConsultantProject Analyst
Rosie KangVice President
Arne OlsonSenior PartnerSenior Advisor

82 Category 2Category 1 & 3
E3 employed an integrated analysis workflow because these categories are inherently interdependent and interactive with each other C1: Technical Potential by Market Segmentation
C2: Optimal Dispatch of DERs
C3: Cost-effectiveness of DERs
PCT

PCT/RIM/TRC/SCT
C1: Adoption Forecast
C3: Cost-benefit Analysis
C2: Unit Dispatchable & Peak-load-reducing Capacity
C2: ELCCs of DERs
C2: Aggregated Dispatchable & Peak-load-reducing Capacity Avoided Costs
Other Benefits
Building, Demographic, Socioeconomic, & Customer Data
Customer Load
Retail Rates & Escalators
Avg System Size
System Costs
Federal & State Incentives
Load Escalators
System Characteristics
Financing Assumptions
Historical Adoption
Adoption Parameters
Mandated Adoption
GWP Inputs:System LOLHs
C1: Programs & Incentives Recommendation
Community Inputs
E3 Research & Expertise
•Multiple scenarios from 2024 to 2030
Input Data
Tasks
C3: Develop Avoided Costs & Other Benefits
GWP Inputs

PV, BESS

PV, BESS
ELCCs and adoption forecasts for EE, DR, EV and other flexible loads will be based on GWP IRP or other public data sources.

PV, BESS

PV, BESS
EV, DR

PV, BESS
Feedback & Iterations
83 Turning potential into adoption requires a multifaceted approach to ensure equitable solar and DER adoption in Glendale Community Outreach
Permitting, Interconnection, and Approval Rules & Process Program & Incentive Design
Equity Strategies
Additional DR, EV, and EE Strategies
Utilize modeling and scenario analysis to evaluate and identify effective, least-cost, and equitable strategies, along with improved and customized avoided cost valuation and cost-benefit analysis for GWP These are the prerequisites for encouraging more adoption – incorporate community inputs and E3/Willdan project experience and expertise Energy Efficiency
Customer-Sited SolarEnergy Storage
Electric Vehicles
Flexible LoadsDemand Response
84 Turning potential into adoption requires a multifaceted approach to ensure equitable solar and DER adoption in Glendale Community Outreach
Permitting, Interconnection, and Approval Rules & Process Program & Incentive Design
Equity Strategy
Demand Response, Electric Vehicles, and Energy Efficiency Utilize modeling and scenario analysis to evaluate and identify effective, least-cost, and equitable strategies, along with improved and customized avoided cost valuation and cost-benefit analysis for GWP .

These are the prerequisites for encouraging more adoption – incorporate community inputs and E3/Willdan project experience and expertise •Additional outreach on federal and state support (e.g., Inflation Reduction Act, Self-Generation Incentive Program, etc.)•Propose adoption programs that use mechanisms that customers intuitively understand•Comprehensive outreach and knowledge campaigns from GWP to inform and educate residents•Intelligible program design •Faster, easier, and scalable permitting, interconnection, and approval process •Additional incentive and program considerations for low- to moderate-income (LMI) customers, disadvantaged communities (DACs), and pollution-burdened areas•Balance expanding solar access with minimizing cost shifts to non-adopters via community solar, virtual solar, and financing programs •Analysis of adoption scenarios to identify the feasibility of City Council targets •Short-list the most effective policy and program options that move towards the targets with improved equity and lower costs•Provide policy and program option alternatives to guide the direction for effective program design •Provide program and incentive options to further promote other DER technologies Requires additional studyFocus of this reportFocus of this report 85 E3 designed the following workflow to support the adoption plan development Estimation of DER potential from all market segments
Enhancement of avoided costs to reflect GWP system plans and characteristics Analysis of adoption scenarios to identify the feasibility of City Council targets and short-list the most promising and effective policy and program options Benefit cost analysis considering direct/indirect economic and non-energy benefits; outline cost and benefit implications of all possible adoption strategies and alternatives to inform GWP’s decision-making process Deep dive into program options to provide program recommendations that balance customer adoption, customer affordability, and achieving value for the whole Glendale community Section 3Community Outreach & Engagement

87 GWP held five community meetings to gather input and feedback, and to share information with the communityStakeholder Participation• Following a resolution by the Glendale City Council, GWP established new goals for solar and energy storage installations, aligning with clean energy targets.•To achieve and analyze the feasibility of these goals, GWP contracted E3 to lead research and analysis efforts, with the goal of presenting an adoption plan to the Glendale City Council in September 2024. •E3 and GWP prioritized engaging renters, multi-family homes, low-income customers, and pollution-burdened customers in their research and creation of adoption scenarios. •E3 and GWP hosted a total of five community meetings, four in person and one virtual, to provide stakeholders with an overview of Glendale's solar and energy landscape and gather direct feedback from the community. •The first three meetings introduced key energy concepts and solicited initial feedback, while the last two meetings presented preliminary research findings and potential solar and DER adoption scenarios.

StakeholderOutreach• GWP made extensive efforts to inform residents and businesses about the community meetings through multiple channels.•These included two bill inserts in customers’ bi-monthly bills, direct mail reminders, a dedicated webpage, press releases, social media posts, email blasts, and a text message blast to over 40,000 GWP customers.•Additionally, an online survey with over 20 questions was distributed to gather input from those unable to attend the meetings.•The survey received over 100 detailed responses, helping E3 and GWP understand customer priorities for the solar and energy storage plan.

Community Meeting Participation• GWP and its consultants held a total of five community meetings to increase attendee knowledge on solar and energy storage in Glendale, discuss the resolution's benefits and challenges, and gather feedback.•Each meeting included a presentation followed by discussions at four key topic stations. The meetings concluded with a Q&A session and an invitation for attendees to submit comment cards.•The first two meetings were held in person, with over 50 and 40 attendees respectively, while the third meeting, a Zoom Webinar, had over 70 attendees, making it the most attended.•The last two meetings, which focused on presenting preliminary research findings and potential adoption scenarios, featured an extended Q&A session instead of discussion stations.•Feedback from the meetings led to a streamlined presentation emphasizing clear graphics and key points.•PDF versions of the presentations for all five meetings are available on GWP’s Solar and Energy Storage Plan’s dedicated webpage. •Press coverage of the third community meeting: •https://glendalenewspress.outlooknewspapers.com/2024/03/18/glendale-water-and-power-talks-highlight-solar-panel-costs-permits

88 ÊMeetings 1-3 took place before the plan design phase of the project, with the goal of informing residents on the project, and gathering feedback to incorporate into the plan design phase.

ÊMeetings 4-5 took place during the plan design phase of the project, with the goal of providing information and progress about the plan, gather feedback, and understand other areas of concern from the community.

GWP held five community meetings to gather input and feedback, and to share information with the communityMeeting 1Meeting 2Meeting 3Meeting 4Meeting 5Wednesday, February 28thSaturday,March 2nd Monday,March 11th Wednesday, May 15thThursday, May 30th Adult Recreation Center201 E Colorado St, Glendale, CA 91205 Sparr Heights Community Center1613 Glencoe Way, Glendale, CA 91208 Zoom/Webinar
Adult Recreation Center201 E Colorado St, Glendale, CA 91205 Sparr Heights Community Center1613 Glencoe Way, Glendale, CA 912086:00 – 8:00 PM10:00 AM – 12:00 PM6:00 – 8:00 PM6:00 – 8:00 PM6:00 – 8:00 PMIn-PersonIn-PersonZoom/WebinarIn-PersonIn-Person 89 Environmental Justices & EquityUnderstanding Barriers to DER Adoption Community Meetings 1-3: community input collections via discussion stations and interactive discussionsInfographics were developed to better inform residents and collect their input

90 C&I Customers Plays a Vital Role in DER AdoptionAffordability and Cost Shifts Community Meetings 1-3: community input collections via discussion stations and interactive discussionsInfographics were developed to better inform residents and collect their input

91 Community meetings had great turnout and local press coverage Community Meeting #5Community Meeting #1Glendale Local Press Coverage Presenter: Jun ZhangPresenter: Eric Cutter
92 Collecting Community Input•Online survey respondent priorities:✚ Affordability and reliability✚Community solar projects to assist renters and low-income households✚Rebates, net metering, and bill transparency✚More education and outreach✚Regulatory and approval process clarity • 40,000 customers surveyed• 100+ unique responses received 93 Collecting Community Input•Comment Cards•Emails•In-Person Notes ✚Upfront rebates for mitigating initial costs✚Net metering for solar and storage✚Expeditedand streamlined approval process✚More guidance on federal and state resources✚More guidance and support in solar and DER adoption process 94 Addressing Community Input•Solar & battery storage contractors on GWP website•Number of installations completedwww.glendaleca.gov/SolarContractors Section 4DER Technical Potential and Market Segmentation in Glendale

Section 4.1Overview
97 Parking Lots
Landfill
Industrial
Municipal
High Desert
Agricultural
Scrubland
Multiple types of solar and storage installations are available for GWP , with different cost implications Customer-OwnedCommunityUtility- Scale
Residential
Commercial
Rooftop
Community
Utility-Scale
Achieving City Council’s 10% Customer Adoption Goal
Lower-Cost Alternatives with Similar Environmental Benefits $/kW System Cost
•Hillside solar is not considered by GWP.•Community solar in practice can involve large rooftop installations as well. 98 ÊRooftop Solar: 313 MWÊParking Canopy Solar: approx. 300 MWÊGround-Mounted Solar: approx. 27 MW Technical Potential of Rooftop, Parking Canopy, and Ground-Mounted Solar in the City of Glendale Rooftop Solar: 313Parking Canopy Solar: 300Ground-Mounted Solar: 27 Technical potential is a metric that quantifies the maximum generation or capacity available for a technology in a given region and does not consider the economic or market viability.Variations in the definition of technical potential and assumptions in filtering criteria may impact results substantially.

Rooftop solar technical potential for the entire City of Glendale, including city-owned properties 99 ÊGWP conducted site-specific analyses on over 100 city-owned properties for potential large-scale rooftop, parking canopy, and ground-mounted solar projects•Over 60 sites are deemed feasibleÊMost sites are filtered out due to their project size of less than 100 kW each and various other developmental constraints, for example:•Not solar ready•Solar not advised by property owners•Historical or community use•Pending roof, structural, reconstruction, ADA, and feeder upgradesÊGWP has identified 10-15 large city-owned sites for developing solar projects•Collectively 10 MW of solar capacity•Six projects approved for construction (5 MW) Achievable solar and storage potential for city-owned properties must account for additional real-world constraintsTechnical Potential of Rooftop, Parking Lot, and Ground-Mounted SolarTotal Analyzed16 MWSolar Ready10 MW 5 MW
•Additional sites evaluated after the initial round of solar site analysis were not included. 6 Sites
10-15 Sites
100+ Sites
Approved for Construction
Section 4.2Parking Canopy & Ground-Mounted Solar
101
ÊE3 identified the boundary of non-residential parking lots 5,000 sq. ft. or greater within the City of Glendale, including city-owned parking lots•Used LARIAC orthogonal imagery* from 2014, similar to NREL’s LA100 study, and included paved areas on C&I and government properties (excluding sidewalks, structures, landscaping, etc.)ÊAssuming 125 W/m2 of parking lot area (approximately 11.6 W/ft²), E3 identified sites capable of siting a solar canopy of 100 kW or more. •Approximately 3.5 kW/parking space accounts for partial coverage and CA laws prohibiting construction over rights-of-way•Minimum system size derived from E3’s experience working with GWP and many other developers of commercial-scale, front-of-the-meter systemsÊSites meeting this criteria were included in the estimate of parking canopy technical potential, which totals approximately 300 MW.•Approximately 1,000 paved parking lots sites totaling 2.42 km2 (3% of Glendale’s city area, approximately 26 million sq. ft.) Technical Potential Methodology - Parking Canopy Solar
Paved lots within Glendale suitable for parking canopy solar projects *For more information about the GIS data, please visit: https://egis-lacounty.hub.arcgis.com/datasets/lacounty::parking-lots-2014-from-lariac/about City LimitParking Lots
Parking canopy solar technical potential refers to the maximum generation capacity that can be sited on developable parking lot canopies in a region assuming economics and grid integration are not a constraint. Variations in the definition of technical potential may impact results substantially. 102
ÊE3’s analysis leverages a dataset of candidate project areas identified for a recent study that estimates urban ground-mounted solar resource potential in the western United States (Wu et. al., 2023*)•Encompass residential, commercial, and other non-residential urban land uses•Locations with imperviousness >= 1% (i.e., buildings, roads, parking lots, etc.), parks and landmarks, wetlands, bodies of water, and forested areas were excluded•Without additional constraints, more than 870 MW of technical potential exists within the City of Glendale, mostly located in the Verdugo Mountains•Applied additional filters:•Limited terrain slope to less than 18% (~10 degrees), as this is more likely to be developed•Excluded protected areas (PAD-US 4.0), as these areas have existing restrictions on energy developmentÊSites capable of supporting >= 100 kW of ground-mounted solar were included in the estimate of technical potential, which amounts to nearly 27 MW, primarily in the Scholl Canyon landfill•Totaling 0.56 km2 (0.7% of Glendale’s city area, approximately 6 million sq. ft.) Technical Potential Methodology - Ground-Mounted Solar
Ground-mounted solar technical potential with basic exclusions (i.e., prior to the application of slope constraint, 100 kW minimum project size, etc.) shown in blueSites satisfying all siting criteria shown in orange (see below) The majority of technical potential is located in the Scholl Canyon landfill Ground-mounted solar technical potential refers to the maximum generation capacity that can be sited on developable lands in a region assuming economics and grid integration are not a constraint. Variations in the definition of technical potential may impact results substantially. * Wu, Grace, et al. “Minimizing Habitat Conflicts in Meeting Net-Zero Energy Targets in the Western United States.” Proceedings of the National Academy of Sciences 120, no. 4 (January 19, 2023). https://doi.org/10.1073/pnas.2204098120.

Section 4.3 Rooftop Solar & Customer Battery Storage
104
ÊHigher income customers tend to adopt larger systems. •California residents tend to install smaller systems than other states, with median sizes ranging from 5.6-7.2 kW-DC across income levels.

Glendale’s current solar and storage penetration pattern skews towards single-family, owner-occupied, and non-LMI households

0.0% 2.0% 4.0% 6.0% 8.0% 10.0%12.0%
SF
C&I
MF
Historical Solar Penetration (%)
Customer Sector

0.0% 2.0% 4.0% 6.0% 8.0% 10.0%
Own
Re ntOwnership

0.0%1.0%2.0%3.0%4.0%5.0%6.0%
LMI
Non-LMIIncome Level
Single family (SF) sector has noticeably higher customer solar penetration, followed by commercial & industrial (C&I) and multi-family (MF) sector Owner-occupied buildings have noticeably higher customer solar penetrationNon-LMI customers have noticeably higher customer solar penetration Adoption Level (% of Total GWP Electric Customers)
107
ÊGlendale has less than 200 customer-sited storage systems, totaling 3 MWh. Most of these systems are owner-occupied, single-family, non-LMI households, with just one large system from commercial customers and none from multi-family residences, reflecting adoption barriers for renter and LMI customers.

Glendale’s current solar and storage penetration pattern skews towards single-family, owner-occupied, and non-LMI households

0.0% 0.2% 0.4% 0.6% 0.8% 1.0%
C&I
MF
SF
Customer Sector

0.0% 0.1% 0.2% 0.3% 0.4% 0.5% 0.6%
Own
Re ntOwnership

0.0% 0.1% 0.2% 0.3% 0.4%
LMI
Non-LMIIncome Level
SF sector has noticeably higher customer solar penetration, while MF and C&I observed minimal adoption Owner-occupied buildings have noticeably higher customer storage penetrationNon-LMI customers have noticeably higher customer storage penetration Adoption Level (% of Total GWP Electric Customers)
108
ÊREPLICA estimates that the City of Glendale has approx. 330 MW rooftop solar potential from residential sector, including single-family and multi-family customers•Owner-occupied, single-family (SF) households have the highest potential, followed by multi-family (MF) rental properties•Difficult to penetrate rental properties because of inherent challenges associated with ownership and split incentives•Resolving these challenges would help unlock over 70% of potential in GlendaleÊExisting Caveats•REPLICA relies on data from 2015, with just 70k households in Glendale. To compare against E3 estimates, E3 scaled REPLICA totals to match current GWP residential customers (approximately 77k total residential customers).•Of the 70k households modeled in REPLICA, 40k are SF and 30k are MF . This breakdown does not perfectly align with the real-world distribution in Glendale as of FY23 (24k SF vs. 53k MF)•REPLICA does not constrain system size based on the customer’s annual load, so E3 ran an unconstrained case for an apples-to-apples comparison Residential Rooftop Solar Technical Potential in GlendaleFrom NREL REPLICA (see appendix for more details) Historical solar adoption is highest among high-income, owner-occupied, single-family households 109
ÊBased on data provided by GWP and other public sources, E3 estimates of rooftop solar technical potential in Glendale are:•Single-Family: 135-269 MW•Multi-family: 108-216 MW•Commercial & Industrial: 188-377 MWÊWide range of sensitivities capture:•Percentage of total roof space available for siting solar (50%, 75%, 100%)•Minimum size and site suitability limitsÊAt this step, system size limits based on the annual load requirement (as specified by the current NEM policy) are not considered•This will be addressed in subsequent analyses to finalize the technical potential in compliance with the rulesÊDoes not include solar potential from private parking lots (carports and canopies), hillside, or landfills Rooftop Solar Technical Potential in GlendaleE3 Estimates vs. NREL REPLICA - 50 100 150 200 250 300 350 400
Single-FamilyMulti-FamilyCommercial &Industrial
Rooftop Solar Technical Potential in Glendale
LowMidHighNREL REPLICA
E3 estimates are based on utility data, compared with NREL REPLICA, in MW * REPLICA data adjusted to account for growth in building stock since publication 110
Rooftop solar technical potential refers to the maximum generation capacity that can be sited on developable rooftops in a region assuming economics and grid integration are not a constraint. Variations in the definition of technical potential may impact results substantially.

Rooftop solar technical potential for planning purposes should further consider system size limits beyond suitability and developable roof areas Project Sunroof

NREL REPLICA
E3
https://sunroof.withgoogle.com/data-explorer/place/ChIJqYPwyDLAwoARpibJ_p6hP-U/https://www.nrel.gov/docs/fy18osti/70901.pdf 466 MW-DC solar installation potential from all sectors, with 80% buildings suitable for solar•Potential estimate includes existing systems•Technical potential is estimated using a machine learning algorithm based on Google’s overhead imagery and weather data•Solar-suitable buildings are identified based on irradiance, orientation, and shading•System size (2 - 1000 kW) is a function of developable roof area, which takes obstacles into account •Does not consider parking lots or fields as eligible sites•Does not limit system size based on applicable program limits (e.g., NEM) 330 MW-DC solar installation potential from residential sector•Potential estimate includes existing systems.•Technical potential is estimated using a statistical model that leverages LiDAR data to determine rooftop suitability•Solar-suitable buildings are identified based on irradiance, orientation, and shading. •System size (> 1.5 kW) is a function of developable roof area, which takes obstacles into account •Does not consider parking lots or fields as eligible sites•Does not limit system size based on applicable program limits (e.g., NEM) 313 MW-DC solar installation potential from all sectors•Potential estimate includes existing systems•Technical potential is estimated using anonymous GWP customer and building data and LA County Assessor parcel data•Developable roof area derived from building footprint with derating factor to account for setback requirements, obstacles, etc.•Glendale solar suitability adjustment of 79.25% (Project Sunroof) to account for structural stability, electrical code compliance, etc.•Any building with enough developable roof area to site a 1 kW system (based on historical installations) is considered solar-suitable •Does not consider parking lots or fields as eligible sites•Runs sensitivities for different rooftop area availability and program limits•Constrains system size based on applicable program limits (e.g., NEM)

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System Size Limit(% of Annual Load)Developable Roof Area (% of Total Roof Area Available) Site suitability, developable roof areas, system size limits, and other constraints shape rooftop solar technical potential Low
Mid
High
50%
75%
100%
110%
110%
110%
Site Suitability(% of Total Building)

79.25%Low
Mid
High
Final E3 Estimates
Technical potential was estimated using anonymous GWP customer and building data and L A County Assessor parcel data. The study calculated roof area for all suitable buildings, then applied developable roof area, system size, site suitability, minimum project size, and other constraints to develop a range of reasonable estimates of rooftop solar technical potential in the City of Glendale.

Minimum Size(kW for Each Rooftop Solar Installation)1 kW 112
ÊObtained anonymous GWP customer and building dataÊFiltered invalid customer accounts (see next page for details)•Excluded government-owned properties and parking lots, accounts without a structure, etc.•Solar suitability adjustment (see right) accounted for structures deemed incapable of supporting rooftop solarÊMerged with parcel data from LA County Assessor •Defaulted to building square footage from tax parcel data due to inconsistencies in customer data•Obtained number of stories from property use code, if available, otherwise estimated based on sector and number of unitsÊCalculated roof area for suitable buildings•Estimated building square footage where missing based on average energy use intensity of accounts with the same meter bill code•Calculated building footprint from square footage and number of stories, then translated to roof area (assuming 0% roof slope)ÊAdjusted roof area based on uniform developable roof area factor of 75% (% of total roof areas available, from LA100 study)•Percentage will vary roof-to-roof based on geometry, but designed to capture 3-foot setback factor required by CA fire code•Obstructions and shading are not explicitly modeled due to the lack of satellite or LiDAR data ÊLimit rooftop solar technical potential based on:•Developable roof area, assuming default power density of 160 W/m2 (approximately 14.86 W/sq. ft., in alignment with NREL REPLICA)•Percentage of customer’s annual load (default to 110% based on GWP’s current NEM program eligibility), assuming DC capacity factor of 20%ÊEnforced minimum size threshold of 1 kW for rooftop solar installations•Based on literature review and analysis of current system sizes in Glendale (where 99.9% of installations are >1 kW historically)ÊDetermined customer battery storage technical potential based on maximum DER ratings allowed by GWP•Assumed only customers with non-zero solar technical potential are considered eligible to install a battery storage system•Minimum storage technical potential is 30 kWh; if solar technical potential exceeds 10 kW, storage technical potential is set to max of 30 kWh or 110% historical average daily usageÊAdditional solar suitability adjustment of 79.25% (based on Project Sunroof data)•Designed to account for factors such as structural stability of roof and electrical code compliance, which cannot be captured solely by customer data Technical Potential Methodology - Rooftop Solar & Customer Battery Storage (E3 Mid-Case) 113
ÊSummary of customer accounts dropped from the technical potential analysis:•Info-only meters: 2,554•Public account holders (e.g., Glendale City): 547•City-owned parking lots: 43•No facility (e.g., vacant lots): 808•Other (e.g., cable and telephone boxes, irrigation systems, outdoor advertising, etc.): 85ÊDuplicated identifiers (i.e., combined account ID, customer ID, and service point ID)•Used most recent descriptors (e.g., meter bill code) and summed the annual energy usage across accounts ÊMerged with LA County Assessor tax parcel data•Public data source that contains detailed property use types and building characteristics, such as number of stories and square footage•Merge occurred at the property level (not unit level) with a success rate of ~73%ÊTreatment of missing data•Categorical variables assigned based on most frequent value associated with similar accounts (e.g., sector)•Missing building square footage data (~ 8%) back-calculated using the average energy use intensity of accounts with the same meter bill code Technical Potential Methodology - Rooftop Solar & Customer Battery Storage (E3 Mid-Case) (Continued) 114
Ê75% of total roof space (based on building footprint) is considered developable for rooftop solar•Accounts for setback factor required by LA County, as well as potential obstructions; based on research conducted for NREL’s LA100 studyÊSolar potential based on 110% of customer’s annual load•Assuming 20% capacity factor (DC), based on default system parameters from NREL’s PVWatts tool for Glendale•Module power density of 160 W/m2 (approximately 14.86 W/sq. ft.), in line with NREL REPLICA estimate for flat roofs ÊNumber of buildings suitable for solar adjusted to 79.25%•Based on Project Sunroof data for Glendale; accounts for factors such as structural stability of roof and electrical code complianceÊStorage potential aligns with maximum DER ratings allowed by GWP for solar and storage systems•Assume only customers with non-zero solar technical potential are considered eligible to install storage•Minimum storage potential is 30 kWh; if solar potential exceeds 10 kW, maximum storage potential of 110% of the historical average daily usage Rooftop Solar and Customer Battery Storage Technical Potential in Glendale (E3 Mid-Case) Note: These figures represent the theoretical maximum of solar and storage capacity under applicable policies and other constraints. In the adoption analysis, systems were sized based on customer needs. 95 MW30%5 kWdc/cust
86 MW27%2 kWdc/cust
132 MW42%18 kWdc/cust
For Mid-Case
Rooftop Solar Potential in Glendale
559 MWh63%29 kWh/cust
216 MWh24%4 kWh/cust
115 MWh13%15 kWh/cust For Mid-Case
Battery Storage Potential in Glendale
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Solar and Storage Technical Potential Capacity by Customer SectorTotal # of Units# of Solar-Suitable UnitsTotal PV Capacity (MW)Total Battery Storage Capacity (MWh)Total Battery Dispatch Capacity (MW)Single-Family23,84319,04695559279Multi-Family61,20149,13086216108Commercial & Industrial9,4747,49113211557 * Statistics for solar-suitable buildings under E3 “mid-case.” Omits sites that could not be categorized.

Total # of Units# of Solar-Suitable UnitsTotal PV Capacity (MW)Total Battery Storage Capacity (MWh)Total Battery Dispatch Capacity (MW)Owner31,90425,355176550275Tenant62,58850,299137339169Manager26140.050.390.20 116
Single-FamilyMulti-FamilyCommercial & Industrial
For Mid-Case, in MWSolar Potential by Sector, Ownership Status, and Building Type E3 estimates identify 313 MW GWP solar potential from all market segments (E3 Mid-Case) * Omits sites that could not be categorized
Key Observations•Single-Family: Owner-occupied single-family residences show the greatest potential for adoption. •Multi-Family: Multi-family rental properties follow closely behind but face challenges due to ownership dynamics and split incentives between owners and tenants. Addressing these issues could unlock significant potential. •Commercial & Industrial: While comprising fewer customers, these sectors have larger average installation sizes, making them significant contributors to achieving the 100 MW DER capacity target. 117
Single-FamilyMulti-FamilyCommercial & Industrial
For Mid-Case, in MWhStorage Potential by Sector, Ownership Status, and Building Type E3 estimates identify 900 MWh GWP storage potential from all market segments (E3 Mid-Case) * Omits sites that could not be categorized
Key Observations•Single-Family: Owner-occupied single-family residences show the greatest potential for adoption. Customers with less than 10 kW solar systems can install up to 30 kWh battery storage systems.•Multi-Family: Multi-family rental properties follow closely behind but face challenges due to ownership dynamics and split incentives between owners and tenants. Addressing these issues could unlock significant potential.•Commercial & Industrial: For large solar systems (>10 kW), maximum storage potential is up to 110% of the historical average daily usage, which constrains the potential from the C&I sectors. 118
Technical Potential Characteristics of GWP Customers – Rooftop Solar and Customer Battery Storage (E3 Mid-Case)SectorTotal # of Units# of Solar-Suitable UnitsAvg Building Area (sq ft/unit)Avg Roof Area (sq ft/unit)Avg Developable Roof Area (sq ft/unit) Avg Annual Energy Usage (kWh/unit)Avg PV Capacity (kW/unit)Avg Battery Storage Capacity (kWh/unit) Avg Battery Dispatch Capacity (kW/unit)Total PV Capacity (MW)Total Battery Storage Capacity (MWh) Total Battery Dispatch Capacity (MW)SectorSingle-Family 23843190461904.42958.42718.818133.934.9829.3314.6794.90558.68279.34Multi-Family 6120149130947.93296.77222.583614.011.754.402.2085.94216.36108.18Commercial & Industrial947474915409.713408.822556.6151322.7417.5915.297.64131.77114.5157.25Building TypeSingle-Family (1 Unit)22953183441939.85970.23727.678329.345.1030.0015.0093.58550.32275.16Single-Family (2+ Units)890703979.28650.13487.603031.491.8811.905.951.328.364.18Multi-Family (Condo)7986011540.80536.06402.0513263.723.7030.0015.002.2218.039.01Multi-Family (2 Units)36042738969.83658.04493.533594.422.0815.007.505.7041.0820.54Multi-Family (3-4 Units)982876601119.06465.37349.033731.341.518.504.2511.5465.1132.56Multi-Family (5-9 Units)1524112283886.70288.45216.342961.981.794.482.2421.9555.0827.54Multi-Family (10-19 Units)122949947865.12234.31175.732925.651.772.241.1217.5722.3211.16Multi-Family (20-49 Units)117359589903.93205.66154.243565.031.881.100.5518.0010.595.29Multi-Family (50+ Units)77016313990.79165.73124.304989.241.420.660.338.964.152.08Commercial & Industrial (Small)505538944059.253113.762335.3215483.018.0616.118.0631.3962.7531.37Commercial & Industrial (Medium)215717438542.905189.233891.9282621.4432.3216.748.3756.3229.1714.58Commercial & Industrial (Large)226218545300.762355.031766.2797166.0823.7612.196.0944.0622.6011.30Building VintagePre-War 24287191421379.00698.83524.126086.423.3417.568.7863.93336.04168.02Post-War 44325355281535.68767.23575.428639.283.9111.625.81138.84412.74206.37Post-1980 23933195011906.86666.83500.129999.203.685.782.8971.79112.7456.37Unknown197314973491.513160.872370.6565804.5025.4218.729.3638.0528.0314.01OwnershipOwner 31904253552360.061220.52915.3916906.846.9421.7110.86175.91550.47275.24Tenant 62588502991262.61545.01408.755729.452.726.733.37136.65338.68169.34Manager 26141583.07807.55605.666260.213.6028.2414.120.050.390.20 * Statistics for solar-suitable buildings under E3 “mid-case.” Omits sites that could not be categorized.

By Sector, Building Type, Vintage, or Ownership
119
Technical Potential Characteristics of GWP Customers – Rooftop Solar and Customer Battery Storage (E3 Mid-Case)SectorBuilding TypeOwnershipTotal # of Units# of Solar-Suitable UnitsAvg Building Area (sq ft/unit)Avg Roof Area (sq ft/unit) Avg Developable Roof Area (sq ft/unit)
Avg Annual Energy Usage (kWh/unit)
Avg PV Capacity (kW/unit)
Avg Battery Storage Capacity (kWh/unit)
Avg Battery Dispatch Capacity (kW/unit)
Total PV Capacity (MW)
Total Battery Storage Capacity (MWh)
Total Battery Dispatch Capacity (MW)Single-FamilySingle-Family (1 Unit)Owner18771149912009.321004.81753.618464.935.1930.0015.0077.85449.73224.87Single-FamilySingle-Family (1 Unit)Tenant416733431628.35815.16611.377722.594.6930.0015.0015.69100.2950.15Single-FamilySingle-Family (2+ Units)Owner4393431007.27737.33552.993776.752.3313.136.570.804.502.25Single-FamilySingle-Family (2+ Units)Tenant451360952.64567.10425.332321.871.4510.735.360.523.861.93Multi-FamilyMulti-Family (Condo)Owner3082391550.68527.03395.2710553.463.6530.0015.000.877.163.58Multi-FamilyMulti-Family (Condo)Tenant4873611538.51543.55407.6615101.623.7330.0015.001.3510.825.41Multi-FamilyMulti-Family (2 Units)Owner11208131004.91650.84488.133614.672.1715.007.501.7612.206.10Multi-FamilyMulti-Family (2 Units)Tenant24821923955.11661.29495.973587.512.0515.017.503.9328.8614.43Multi-FamilyMulti-Family (3-4 Units)Owner14671089907.15366.60274.953685.851.688.584.291.839.344.67Multi-FamilyMulti-Family (3-4 Units)Tenant835765711154.17481.73361.303738.881.488.494.249.7055.7827.89Multi-FamilyMulti-Family (5-9 Units)Owner131310531039.96443.09332.313268.542.014.652.322.124.892.45Multi-FamilyMulti-Family (5-9 Units)Tenant1392811229872.33273.95205.462933.231.774.472.2319.8350.1825.09Multi-FamilyMulti-Family (10-19 Units)Owner7546181042.35303.14227.353764.312.292.151.071.411.330.66Multi-FamilyMulti-Family (10-19 Units)Tenant115409329853.37229.75172.312870.081.732.251.1316.1620.9910.50Multi-FamilyMulti-Family (20-49 Units)Owner141111261019.18215.43161.574641.722.051.120.562.311.260.63Multi-FamilyMulti-Family (20-49 Units)Tenant103248463888.61204.36153.273421.841.851.100.5515.699.334.66Multi-FamilyMulti-Family (50+ Units)Owner8036581001.66165.94124.466136.251.600.780.391.050.510.26Multi-FamilyMulti-Family (50+ Units)Tenant68985655989.53165.70124.284855.721.400.640.327.913.641.82Commercial & IndustrialCommercial & Industrial (Small)Owner189414623811.552773.462080.1014439.197.3815.097.5510.7922.0611.03Commercial & IndustrialCommercial & Industrial (Small)Tenant316024314209.213319.062489.3016115.118.4716.728.3620.5940.6620.33Commercial & IndustrialCommercial & Industrial (Medium)Owner149912217505.924727.453545.5978205.9930.3814.347.1737.1117.528.76Commercial & IndustrialCommercial & Industrial (Medium)Tenant65752110972.296271.084703.3192965.8336.8522.3411.1719.2111.655.82Commercial & IndustrialCommercial & Industrial (Large)Owner212517425115.432147.981610.9891469.2821.8111.465.7338.0019.979.99Commercial & IndustrialCommercial & Industrial (Large)Tenant1371128175.385566.664175.00185528.8653.9523.3711.686.062.621.31•Statistics for solar-suitable buildings under E3 “mid-case.” •Omits sites that could not be categorized. No “Manager” ownership status.

By Sector, Building Type, and Ownership (excludes Vintage) Section 5Dispatchable Capacity and Demand Reduction Capacity

121
E3 reviewed GWP’s IRP focusing on load & DER forecasts to ensure accurate system representation and inform study design Today
Inform Study DesignEvaluate Adoption LeversReview IRP Inputs Reviewed IRP Inputs•To properly support GWP’s DER strategy, E3 must comprehensively understand GWP’s system•The E3 team conducted a thorough review of GWP's Integrated Resource Plan (IRP), load and DER adoption forecast•The review included a detailed analysis of GWP's assumptions, methodologies, and data inputs used in the development of the IRP Evaluated Adoption Levers•The IRP review focused on evaluating GWP's resource mix, key upcoming decisions, and levers that may accommodate the adoption of DERs•It also included an evaluation of the approach to determining the reliability of GWP's proposed resource plan•E3 also had a focused review of GWP’s assumptions and methodologies for assessing the potential for DERs and load growth Informed Study Design•The E3 team leveraged its findings to inform other components of this study, including but not limited to the DER reliability analysis, targeted DER adoption strategies, and the cost benefit analysis Key Decision NeededGWP Goal Deadline
DER OpportunityDER Opportunity

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Role of Local Clean Energy Resources
GWP faces many challenges in transitioning to a cleaner grid, and local clean energy resources could provide significant support Glendale's Clean Energy Vision•60% RPS by 2030 (CA regulatory requirement)•100% Clean Energy by 2035 (Glendale goal)Transmission & Land Constraints•Procuring new renewables outside of the City•Procuring new renewables within the CityIntegrated Resource Plan (IRP) Planning Challenges•Integrating renewables, coal retirement, and hydrogen combustion turbine (CT) conversion•Maintaining system reliability Maintaining leadership in clean and renewable energy
Unlocking more local generation
Reducing fossil fuel generation (Grayson Repower, etc.) System Context and Challenges

123
Resource adequacy (RA) is increasing in complexity and importance as the grid shifts to low-carbon resources ÊThe transition towards renewables and storage introduces new complexity in resource adequacy planningÊThe concept of planning exclusively for “peak” demand is becoming obsoleteÊInstead, long stretches with low solar and wind output, corresponding with high loads, are the times of most challenging resource adequacy needsÊAs more of one resource is integrated, the net peak hours shift to other times, reducing its capacity value or ELCC Peak load reductions decline with increasing adoption
Effective Load Carrying Capacity (ELCC)•ELCCmeasures a resource's contribution to reliability based on the incremental quantity of load that can be satisfied by adding the resource to the grid•ELCC expresses the capacity contribution of intermittent and energy-limited resources in terms of equivalent “perfect” capacity (capacity that is always available)•For example, if the ELCC of solar is 50%, then an electricity system with 100 MW of solar (i.e., 50 MW of ELCC) would achieve the same reliability as an electricity system with 50 MW of a perfect resource Diminishing Value of Solar ELCCDiminishing Value of 4h Storage ELCC Schlag et. al., "Capacity and Reliability Planning in the Era of Decarbonization: Practical Application of Effective Load Carrying Capability in Resource Adequacy," Energy and Environmental Economics, Inc., August 2020. Available at: https://www.ethree.com/elcc-resource-adequacy/ Peak load reductions decline with increasing adoption
124
ÊE3 has resource adequacy experience across California:•CPUC IRP – California-wide ELCC work•CAISO – CAISO DR ELCC work•LADWP – neighbor for GWP•SMUD – another smaller-sized CA utility ÊFor this study, E3 developed GWP-catered approximations of ELCC without having to conduct extensive Loss-of-load Probability (LOLP) modeling E3 leveraged its experience performing RA analyses and used Effective Load Carrying Capacity (ELCC) results from other CA work LADWP
Portland General ElectricNorthwestern Energy
Florida Power & Light
Xcel Energy
Hawaiian Electric Company
El Paso Electric
NV EnergySacramento Municipal Utilities District
States where E3 has provided direct support to utilities, market operators, and/or state agencies to perform RA modeling or develop RA frameworksAreas where E3 has worked with other clients to examine issues related to resource adequacy OPPD
Nova Scotia Power
New Brunswick Power

NYISOPJMCAISO
SRP
LES
PUCT
Black Hills Energy
Oregon PUCPuget Sound Energy

NYSERDA
E3 has worked directly with utilities across North America to study resource adequacy needs 125
ÊCustomer adoption forecasts for distributed solar and storage were modeled across scenarios S1-S5.ÊFor electric vehicles (EVs), demand response (DR), and energy efficiency (EE), a single adoption scenario was modeled based on GWP’s IRP .ÊFurther details are available in Section 7: Adoption and Impact Analysis.

E3 calculated the estimated dispatchable capacity and demand reduction that can be achieved through the adoption plan DER Nameplate Capacity
DER Effective Capacity
DER ELCCs
ÊFor example, if solar has an ELCC of 50%, then a system with 100 MW of solar capacity would provide the same reliability as a system with 50 MW of an ideal, always-available resource. In this case, the effective capacity of solar is 50 MW.ÊFurther details are provided in the following slides.

ÊELCC measures a resource’s contribution to grid reliability by quantifying the additional load the system can support. This concept applies to dispatchable and peak-load-reducing DERs as well.ÊE3 developed tailored ELCC approximations for GWP .ÊFurther details are provided in the following slides. 126
E3 designed this approach for approximating GWP DER ELCCs based on data availability 2024 DER Shed or Provided Power Potential
GWP DER ELCCs*
Utility-Scale Battery Storage Marginal ELCC CurveFrom 2022 CPUC ACC Capacity Allocation Hours (2024-2030) 2024 DER End-Use Profiles (Normalized)
GWP DER ELCCs*
Loss-of-Load Hours (LOLH)From 2022 CPUC ACC Capacity Allocation Hours (2024-2030) Approximated from 2022 CPUC IRP DR study
Profiles simulated by this study, or approximated from previous E3 work Approximations based on E3’s work in California and across the U.S.

GWP DER ELCCs*
1 2
3 From 2023 CPUC IRP RESOLVE Utility-Scale 4-hr Battery Storage Marginal ELCC Curve (2024-2030) * Post-processed as a range (±5%) based on the calculated value to account for uncertainties that were not fully addressed Loss-of-Load Hours (LOLH)Electric Vehicles
Solar and Energy Storage
Demand Response
127
Key Results: Approximations of GWP DER ELCCs in 2027
Electric VehiclesSolarEnergy StorageDemand Response
GWP BTM solar profiles from PVWatts (used across the whole study)GWP BTM storage profiles simulated by this study (used across the whole study) CA LDEV Shed Potential data from E3 2022 CPUC IRP DR studyFrom E3 CAISO DR ELCC study assuming 15 events per year and 1-hr max duration (approximating GWP Power Saving Program)Exceptions:•LDEV VGI: excluded due to its relatively low deployment level projection in the near term•Energy Efficiency: peak saving forecasts are available from the GWP IRP , which are assumed to already account for capacity contributions •LDEV: Light-Duty Electric Vehicle•VGI: Vehicle Grid Integration 0%
Range
ELCC Range (%)
128
Can GWP reach 100 MW dispatchable and peak load reduction capacity by 2027?ÊCustomer-owned solar and storage would provide reliable peak load reductions of 10 MW or less by 2027ÊIncluding other DERs such as demand response, managed electric vehicle charging, and energy efficiency could theoretically provide peak load reductions of 20-44 MW by 2027ÊEffective Capacity: requires approximately 200-300 MW customer solar, 40-60 MW customer battery storage, and other DERs by 2027ÊNameplate Capacity: theoretically feasible with significant utility investment, suggest considering a MW nameplate capacity goal and a later target year Achieving 100 MW Additional DER by 2027:
•Achieving 100 MW additional effective capacity, considering DER’s ability to reduce GWP system peak demand, will require 200-300 MW DER nameplate capacity coming online by 2027.•A more realistic target is achieving 100 MW additional DER nameplate capacity with a later target year.

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DERs have the potential to avoid several system costs
Transmission SubstationTransmission LineTransformer
Transformer
Feeder
Feeder
Primary Distribution LineDistribution/ Final Line TransformerSecondary Distribution Line 10,000 Customers
Primary Distribution Line
Some overloads can be managed with low- cost switching
Distribution Substation1,000 Customers10 CustomersCircuitServiceTransmission Solar Plant
Generation100,000 Customers1 Million Customers
Meter
Customer
Customer
1 CustomerCustomer
Service Panel
Primary DistributionSecondary Distribution
131
ÊOrigin: 1978 Public Utilities Regulatory Policy Act (PURPA)•Utilities must pay co-generators/qualifying facilities (QF) their ‘avoided costs’–Avoided cost is the incremental cost of electric energy or capacity which, but for the purchase from the QF , a utility would generate itself or purchase from another source–Avoided costs analysis enables the quick evaluation of the costs or benefits of a particular action while avoiding more time-consuming, complex full planning analysis•FERC outlines principles but gives each state the authority to determine its own approaches ÊSeparate from PURPA, many states turned to this concept to value Energy Efficiency and Demand Side Management•The evolving electricity system makes this valuation more complex than it once was Increasing complexity of the electrical system requires a new approach to translate supply-side investments to avoided costs 132
Avoided cost must evolve to reflect the value of DER for a low-carbon grid – a new planning paradigmThen NowPlanning TargetsReliabilityReliability and clean energyMarginal Fixed CostsCombined Cycle Gas TurbineCombustion Turbine Wind, solar, and storageMarginal Variable Costs & EmissionsMostly fuel in all hours - highLimited fuel needed for ramping and reliability - low or zero in most hoursHourly VariabilityModest SignificantPolicy GoalsEncourage conservationEncourage electrification Peaking and baseload resources to meet reliability targets Portfolio of resources selected to meet reliability, clean energy, and GHG targets Energy Efficiency Measures
Customer-Sited PV
Load reducing, fixed shape resources
Storage
Transportation Electrification
20°
Building Electrification
Load increasing, flexible shape resources
Supply SideDemand Side
133
Principles of Avoided Cost FrameworkMarginal costs represent the costs that the utility avoids by installing a marginal unit of DER relative to the existing/planned portfolio. These costs serve as implicit and explicit price signals to achieve energy, reliability, and climate goals. Marginal Long-TermLong-term costs represent the long-run avoided costs of a DER over its lifetime, aligning with planning expectations for meeting long-term goals.

Technology A gnosticThese costs provide a single, flexible technology agnostic set of avoided costs that can be applied to all types of DERs.Load ReducingLoad ShiftingLoad Increasing 134
Translating avoidable system costs to avoided cost componentsEnergy Generation CapacityGreenhouse Gas/RenewableTransmission Capacity Others
Marginal cost to serve one MWh of load in each hour of the year Marginal cost to add one kW of qualifying resource capacity to the systemMarginal cost to reduce one ton of greenhouse gas (GHG) emissions and/or procure one Renewable Energy Credit (REC)Marginal cost to reduce one kW of transmission capacity needed to meet load growthDistribution CapacityMarginal cost to reduce one kW of distribution capacity needed to meet local load growth – true value is highly location-specific Monetized costs associated with losses, methane leakage, ancillary services, and others 135
ÊPrinciple: ensure values were customized, defensible, and aligned with GWP's unique system plans and characteristics while avoiding a complete overhaul of avoided costs to save time and resources ÊUsage: avoided costs are used to quantify DER’s benefits to GWP and as part of the Net Energy Billing (NEB) tariff ÊApproach: E3 calculated GWP avoided costs based on the CPUC 2022 Avoided Cost Calculator (2022 ACC) because…•Precedence: GWP has previously used the CPUC ACC to evaluate energy efficiency programs, establishing a precedent.•Versatility: The hourly stream format of the CPUC ACC is adaptable for evaluating various DERs.•Challenges with Alternatives: Estimating proxy utility-scale resources for each DER can be difficult, especially for flexible resources and EVs.

Principles of calculating GWP avoided costs
$0$50$100$150$200$250$300$350
JanFe bMarAprMayJunJulAugSe pOctNovDec
Average Monthly Value of Energy ($/MWh)
Methane LeakageLossesAncillary ServicesDistribution CapacityTransmission CapacityGeneration CapacityEnergyGHG Adder &Re balancingCap and Trade SCE CZ9 Monthly Average Avoided Costs in 20302022 CPUC Avoided Cost Calculator Month
136
Common usage of the CPUC Avoided Cost Calculator (ACC) – the basis of GWP's avoided costs ÊEnergy Efficiency and Demand Response Evaluation•Comparing the total cost of new efficiency measures to the marginal cost savings of the utilityÊSelf Generation Incentive Program (SGIP) Energy Storage Evaluation•What ratepayer benefits and GHG reductions are being realized by behind-the-meter (BTM) energy storage?ÊBuilding and Transportation Electrification•Economic and GHG benefits of utility electrification programsÊValue of Solar•Cost-shift to non-participating customers due to compensating BTM solar at the retail rate 72°
ÊThe CPUC Avoided Cost Calculator (ACC) is a simplified representation of the utility-integrated resource plan to answer:•Are Distributed Energy Resources (DER) more cost-effective than supply-side alternatives? ÊRate Setting•The ACC sets export compensation for prosumers 137
E3 updated four components tailored to GWP’s systemsComponents2022 ACC MethodologyUpdates for GWPGeneration CapacityAssumed 4-hr storage is the marginal capacity resource and calculated the opportunity cost of deferring the investment by one yearAssumed various capacity resources by year according to the GWP IRP Renewable/GHGEscalated from the 2035 “shadow price” on the carbon constraint in RESOLVE (the IRP’s capacity expansion model) Removed the GHG adder component and added avoided RECs because GWP plans its system according to a Renewable Portfolio Standard and Clean Energy Standard while the CPUC IRP system is mainly driven by GHG reduction goalsTransmission CapacityProvided by Southern California EdisonAssumed zero for GWP because GWP does not anticipate any change in its transmission upgrade regardless of DER adoptionLossesFrom the CPUC IRPUpdated for GWP (7% transmission losses and 7% distribution losses) Energy, Distribution Capacity, Methane Leakage, and Ancillary Services were not updated due to a lack of detailed data. For example, GWP’s IRP does not have hourly energy prices, which made it challenging to update energy avoided costs. 138
$0$50$100$150$200$250$300$350$400
JanFe bMarAprMayJunJulAugSe pOctNovDec
Average Monthly Value of Energy ($/MWh)
Methane LeakageLossesAncillary ServicesDistribution CapacityTransmission CapacityGeneration CapacityEnergyGHG Adder & RebalancingCap and Trade $0$50$100$150$200$250$300$350$400
JanFe bMarAprMayJunJulAugSe pOctNovDec
Average Monthly Value of Energy ($/MWh)
Methane LeakageLossesAncillary ServicesDistribution CapacityTransmission CapacityGeneration CapacityEnergyGHG Adder & RebalancingCap and TradeRE C Result: total avoided costs for GWP are similar to the CPUC ACCCPUC 2022 ACCSCE CZ9 2027GWP Customized Avoided Costs2027 * The CPUC ACC is in 2020 calendar year while GWP avoided costs are in 2018 calendar year Added REC and removed GHG Adder & Rebalancing
Updated capacity avoided costs are higher than the CPUC ACC 139
Result: total avoided costs for GWP are similar to the CPUC ACC CPUC 2022 ACCSCE CZ9 2027GWP Customized Avoided Costs2027

140
ÊThe avoided cost of capacity reflects the net fixed cost of a new resource that would fulfill the capacity needsÊAvoided capacity costs were calculated as a “residual” of a given capacity resource, meant to reflect the fixed cost of a new resource that is not offset by margins from the energy market•Also described as the “missing money”ÊE3 used Real Economic Carrying Charge (RECC) to derive generation capacity avoided costs for 4-hr storage, consistent with the 2022 ACC, with updated resource costs from GWP’s IRP* ÊE3 calculated the Net Cost of New Entry of the re-powering gas plant and new hydrogen power plant, using GWP’s IRP costs Calculation of Generation Capacity Avoided Costs Calculation of Avoided Capacity Cost$/kW-yr Energy + Ancillary Service Revenues
Avoided Generation Capacity Value ($/MW-yr)
Annualized Fixed Resource Costs
Ancillary service: a group of grid services for balancing electricity supply and demand in real-time and ensuring the smooth operation of the grid *For more details of the RECC method, see 2022 ACC documentation (pg. 38) 141
ÊCapacity avoided costs were calculated assuming different marginal capacity resources in different years given the planned capacity resources in GWP’s IRP . •2024-2025: re-powering of gas plant•2026-2034: 4-hr storage•2035 onward: hydrogen CTÊAvoided capacity costs in 2024-2026 should technically be zero because GWP is currently building Grayson Repowering and battery storage, which cannot be avoided by DERs.

E3 calculated capacity avoided costs assuming different capacity resources in different years Grayson ICE generatorsHydrogen conversion by 2035
Source: GWP 2024 IRP
Grayson 4-hr storage
142
GWP’s avoided capacity costs are higher than the 2022 CPUC ACC due to higher storage costs and hydrogen CT $- $50 $100 $150 $200 $250 $300 $350 $400
2024202520262027202820292030203120322033203420352036203720382039204020412042204320442045 Generation Capacity Avoided Costs ($nominal/effective kW-yr) GWP2022 ACC
GWP capacity avoided costs are low in the near-term because of low cost in gas plant repoweringGWP capacity avoided costs are higher than the 2022 ACC due to higher storage cost assumed in GWP’s IRPGWP capacity avoided costs stay high after 2035 because a hydrogen CT is assumed to be the marginal capacity resource The 2022 ACC assumes 4-hr storage is the marginal capacity resource for all years Year
143
ÊE3 calculated avoided REC as the additional revenue needed beyond the energy market to cover levelized costs for new solar resources. ÊLevelized costs for new solar are consistent with the GWP IRP and reflect higher solar PPA prices in the near term. ÊAvoided REC are discounted by the RPS percentage. Given that GWP plans to serve 100% clean energy by 2035, the RPS is assumed to be 100% after 2035.ÊThe avoided REC is ~5$/MWh in the near term due to RPS discounting and increases over time as solar earns fewer energy revenues due to curtailment.

Calculation of Avoided Renewable Energy Credits (REC)Calculation of Avoided REC$/kW-yr Energy
Annualized Fixed Resource Costs of Utility Solar
REC
Avoided REC
Discounted by RPS% Trajectory
Section 7Adoption and Impact Analysis

Section 7.1Scenario Design Framework
146
Adoption and Impact AnalysisE3 employed the IDSM tool to assess the predicted adoption of distributed solar and storage according to several different scenarios with varying utility incentives and rate designs•The scenarios were evaluated not only on whether they reached the 10% target but also on their ability to distribute the benefits of DERs equitably among more than a dozen different customer segments•Bill savings, avoided costs, emissions, and other operation metrics were calculated in the model The balance between affordability and adoption impact is a careful consideration when selecting program portfolios to ensure equitable growth•IDSM modeling results enabled the E3 team to reveal the feasibility of achieving the 10% adoption target through a strategic combination of robust community outreach, utility incentives, and a rate design that encourages adoption while also mitigating ratepayer impacts 147
Possible InterpretationsÊEligible systems include customer-sited solar, solar + storage, and/or standalone storage systemsÊAchieve the resolution by December 31st, 2027ÊEligible GWP electric customer adoption includes:1.Rooftop solar owned, financed, or leased by single-family and commercial & industrial customers (one system for one electric customer)2.Rooftop solar owned, financed, or leased by multi-family property owners/managers and commercial & industrial customers under virtual solar programs and shared among tenants and unit owners (one system for multiple electric customers)3.Subscribers of off-site solar solutions like community solar, solar share, and green rate options (one project for numerous electric customers) Possible InterpretationsÊAchieve the resolution by December 31st, 2027ÊEligible demand management measures include solar, storage, electric vehicles, energy efficiency, and/or demand response (both load shedding and load shifting)ÊFocused on additional measures and exclude existing capacity ÊPeak dispatchable capacity: battery storage and EVs with bidirectional charging/discharging capability (V2G)ÊPeak load-reducing capacity: solar, EV managed charging (V1G), energy efficiency, and demand response which either shave load during peak periods or shift load to off-peak periodsÊCapacity measured by nameplate capacity or effective capacity (kW) How we interpret the City Council’s resolution is importantIn August 2022, the Glendale City Council passed a resolution expressing their intent to adopt policies and practices aimed at achieving the goal of having at least 10% of GWP customers adopt solar and energy storage systems by 2027, and to develop additional demand management measures with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW.At least 10% of GWP customers adopt solar and energy storage systems by 2027 Develop additional demand management measures, with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW Expanded Eligibility Criteria •In general, Effective Capacity = Nameplate Capacity * ELCC•Effective Load Carrying Capability (ELCC) measures a resource's contribution to reliability based on the incremental quantity of load that can be satisfied by adding the resource to the grid Key Clarification Question: Which systems qualify for the 10% adoption target? Standalone SolarSolar + StorageStandalone Storage
Key Clarification Question: 100 MW nameplate or effective capacity?Nameplate CapacityEffective CapacityVS. 148
ÊProgram proposals ranked by overall qualitative performanceÊReasonable DER compensation levels that mitigate cost shifts are preferred Qualitative screening analysis prioritizes program and policy options crucial for achieving City Council targets over othersPriority Level

Section 7.2Scenario Design Framework
150
The adoption scenarios represent theoretical upper bounds of how much adoption we can expectAdoption Level Optimal Adoption Rate in Ideal ConditionsAdoption Rate in Practical Conditions Adoption Impeded by Real-World Constraints
E3 developed best-case scenarios for evaluating the theoretical feasibility of achieving adoption targets.•While E3 aimed to account for consumer decision-making across different customer groups and the split incentive issue for renters, these methods fall short of fully capturing the broad range of financial and non-economic barriers that households face in adopting DERs. The scenarios represent an upper bound of what is possible if these barriers were mitigated.•The study assumes perfect implementation from GWP providing additional utility support and improved access for renter and LMI customers. Other real-world barriers and constraints that naturally exist regarding admin costs, admin resources, pace of program delivery, community participation rate, etc., are not considered.•The Cost and Benefit Analysis section of this report provides a more comprehensive view of costs and benefits, examining direct and indirect economic benefits and costs as well as environmental, societal, and other non-economic benefits and costs.When interpreting these results in a real-world context, several considerations must be made.•The adoption level will be further limited by how much progress GWP can make on providing solutions for renters and LMI customers and for improving community outreach, support, and permitting processes.•Correspondingly, E3 expects utility program costs to be higher because additional incentives must be imposed to fill in the gap of adoption shortfall.

ILLUSTRATIVE
151
Scenario 1: Continue NEMScenario 2: Targeted LMI/DACs & MF AdoptionScenario 3: BalancedScenario 4: Widespread Adoption E3 evaluated four program scenarios to identify target feasibility and show trade-offs in adoption, equity, and costsNEM CompensationAdditional IncentivesAccess for Renter and LMI CustomersProvide More Utility Support Program & Incentive Design
Address Additional Barriers•Low and Moderate Income (LMI)•Disadvantaged Communities (DACs)•Multi-family (MF) 152
Each scenario features a portfolio of programs, including some combination of customer solarand storage billing compensation mechanisms, additional utility incentives, other utility support, etc.

Various adoption scenarios capture multifaceted programs targeting various property types and communities No.ScenariosNarrative & Philosophy0Business as UsualReflects current GWP policies at business-as-usual conditions without any additional incentive programs or other utility support.1Continue Current NEMReflects current NEM policies without new incentive programs, but with improved outreach, support, and improved permitting processes.2Targeted MF LMI AdoptionAims to reach as much adoption as possible while maintaining high standards for equitable implementation. Focuses on minimal cost shifting and promotes MF LMI/DAC adoption via direct install programs.3BalancedAims to reach a balance between S2 and S4, with a focus on increasing customer adoption while reducing cost shifting potential, supplemented with MF LMI/DAC upfront incentives as needed.4Widespread AdoptionAims to reach adoption goal with an emphasis on customer-sited solar and storage. Focuses on maximizing adoption with supplemental upfront incentives as needed.5Direct InstallServes as a high-cost bookend under which GWP direct installs up to 10% of customer with solar. Emphasis on MF properties (lower cost per customer) and adoption in LMI/DACs.

Encouraging Customer Adoption
Realizing Value for Grid & CommunityManaging Cost-Shift & Affordability Balancing Multiple Objectives
Scenarios are guided by values from stakeholders, policy, and GWP , and for each scenario the proposed program portfolio was scored on how well it captured each value from multiple perspectives.

S0 and S5 represent bookend scenarios derived from standalone, simplified back-of-envelope calculations, intended to provide a broad estimate of magnitude. 153
Other Utility Support
The scenarios outline different pathways towards Glendale’s DER adoption targetNEM CompensationAdditional Incentives*Renter and LMI Customer Barriers S1S2Targeted LMI MF Adoption
S3Balanced
S4Widespread Adoption
S5Direct Install
Net energy metering at retail ratesNet energy billing at avoided costs Net energy metering at retail rates
Net energy metering at retail rates
Net energy billing above avoided costs but below retail rates Federal and stateFederal and state, utility direct install for LMI/DAC MF customers Federal and state, and direct install for MF renter LMI/DAC customers Federal and state, 5-yr payback utility incentive for all MF customers Federal and state, 7-yr payback utility incentive for LMI/DAC MF buildings Persist
Optimistic outlook on enhanced community outreach and support, along with improved permitting processes starting early 2025 Optimistic outlook for providing renter and LMI customer solutions starting early 2025 S0Business as UsualNet energy metering at retail ratesFederal and statePersistAt the Current Level PersistAt the Current Level
Evaluate Adoption StrategiesReferenceHypothetical Feasibility *Additional incentives is a general representation of all types of incentives including potential upfront incentives and performance-based incentives offered by GWP. Assuming receipt of GWP incentives requires customers dispatch battery storage against utility signals to maximize community benefits.

Continue Current NEM
154
Assumptions on Additional Incentives and Solutions for Renter and LMI CustomersAdditional incentives modeled are a general representation of all types of incentives including potential upfront incentives and performance-based incentives offered by GWP•Assuming receipt of GWP incentives requires customers to dispatch battery storage against utility signals to maximize community benefits Assume renter and LMI access can be provided with virtual solar or other financing solutions starting early 2025•In practice, real-world solutions to explore later may include on-bill financing options, green leases, and off-site solar solutions like community solar, solar share, green rate, and virtual net metering, all of which are pivotal for cost reduction and broadening access to multi-family, low-income, or tenant households

155
ÊTo distinguish consumer decision-making among different household types, E3 assigned varying discount rates (investment hurdle rates) based on income levels and customer sectors, accounting for the frictions to DER adoption.•Higher discount rates (16%) were assigned to Multifamily, C&I, and LMI customers, while other customers received a 7% rate (normal discount rate assumption in this study), determined based on historical solar and storage adoption in the City of Glendale.•These rates were applied solely to distinguish consumer adoption behavior in the adoption model and were not used in the downstream cost-benefit analysis.ÊSpecifically, renters and multifamily households may encounter a “split incentive” issue, where tenants who benefit from bill savings do not control the rooftop, and building owners who make upgrades don’t directly benefit from utility savings. There is no existing work to mathematically characterize split incentives; therefore, to model the effect of split incentives on adoption, two scenarios were considered:•Split Incentives Fully Resolved: Renters are assumed to behave similarly to owners, leading to the application of the same discount rate for both groups.•Split Incentives Persist: Renters are assumed to have a significantly higher discount rate (100%), effectively preventing the adoption of solar and storage systems in rental units.ÊFor this study, E3 focused on quantifying the impact of resolving split incentives on DER adoption, rather than evaluating the effectiveness of specific solutions. In practice, solutions for addressing split incentives between owners and tenants typically involve programs designed to realign financial incentives for energy measures (details in the Potential Program and Policy Options section).

Clarifying Assumptions in Modeling the Resolution of Split IncentivesBuilding TypeOwnership StatusIncome ClassDiscount Rate(Split Incentives Fully Resolved)Discount Rate(Split Incentives Persist)Single-FamilyOwnerLMI16%16%Single-FamilyOwnerNon-LMI7%7%Single-FamilyTenantLMI16%100%Single-FamilyTenantNon-LMI7%7%3 Multi-Family Low-RiseOwnerLMI16%16%Multi-Family Low-RiseOwnerNon-LMI16%16%Multi-Family Low-RiseTenantLMI16%100%Multi-Family Low-RiseTenantNon-LMI16%100%Multi-Family High-RiseOwnerLMI16%16%Multi-Family High-RiseOwnerNon-LMI16%16%Multi-Family High-RiseTenantLMI16%100%Multi-Family High-RiseTenantNon-LMI16%100%C&I SmallOwnerN/A16%16%C&I SmallTenantN/A16%100%C&I MediumOwnerN/A16%16%C&I MediumTenantN/A16%100%C&I LargeOwnerN/A16%16%C&I LargeTenantN/A16%100%E3’s approach draws on methodologies established in NREL studies1, 2, which were further tailored to fit the specific needs of the analysis.1.“Chapter 8: Equitable Rooftop Solar Access and Benefits.” In LA100 Equity Strategies, National Renewable Energy Laboratory. NREL/TP-7A40-85955. https://www.nrel.gov/docs/fy24osti/85955.pdf. 2.2. Affordable and Accessible Solar for All: Barriers, Solutions, and On-Site Adoption Potential. Golden, CO: National Renewable Energy Laboratory. NREL/TP-6A20-80532. https://www.nrel.gov/docs/fy21osti/80532.pdf.3.The adjusted discount rate for split incentives applies to all renters except non-LMI single-family tenants, due to their historically high adoption rates.

Section 7.3 Key Model Results
157
Key Results: Bill Savings and Utility Incentive Levels by ScenarioVariations in customer segments may lead to a range of outcomesNEM Compensation 2025 Level ($/kWh)Additional Incentives* 2025 Level ($/W) S1Continue Current NEM
S3Balanced
S4Widespread Adoption
S5Direct Install
Net energy metering at retail rates
Net energy metering at retail rates
Net energy metering at retail rates
Net energy billing above avoided costs but below retail rates Federal and state
Federal and state, utility direct install for all MF renter LMI/DAC customers Federal and state, 5-yr payback utility incentive for all MF customers Federal and state, 7-yr payback utility incentive for LMI/DAC MF buildings S0Business as UsualNet energy metering at retail ratesFederal and state Evaluate Adoption StrategiesReferenceHypothetical Feasibility *Additional incentives is a general representation of all types of incentives including potential upfront incentives and performance-based incentives offered by GWP. Assuming receipt of GWP incentives requires customers dispatch battery storage against utility signals to maximize community benefits.

0.13-0.28

0.00 0.11-0.22

0.06-0.25

0.13-0.28

0.00 0.13-0.28

0.00 N/A
N/A

0.00 0.00

1.3-1.5

1.4-1.5

1.0-1.2

1.7-1.8

0.00 0.00
S2Targeted LMI MF AdoptionNet energy billing at avoided costsFederal and state, utility direct install for LMI/DAC MF customers

0.09-0.19

0.08-0.28

2.6 1.65
N/A
N/A
158
Key Results: Adoption Level, Equity, and Key Observations by ScenarioThese adoption scenarios represent the best-case adoption forecast *Additional incentives is a general representation of all types of incentives including potential upfront incentives and performance-based incentives offered by GWP. Assuming receipt of GWP incentives requires customers dispatch battery storage against utility signals to maximize community benefits.

Key ObservationsNEM Compensation 2027Equity & Access2027Customer AdoptionOther Utility SupportAdditional Incentives*Renter and LMI Customer Barriers (Split Incentives) S1Continue Current NEMS2Targeted LMI MF Adoption
S3Balanced
S4Widespread AdoptionS5Direct Install
Net energy metering at retail ratesNet energy billing at avoided costs Net energy metering at retail rates
Net energy metering at retail rates
Net energy billing above avoided costs but below retail rates Federal and state
Federal and state, utility direct install for LMI/DAC MF customers Federal and state, and direct install for all MF renter LMI/DAC customers Federal and state, 5-yr payback incentive for all multifamily customers Federal and state, 7-yr payback utility incentive for LMI/DAC MF buildings Persist

9.6 %60 MW

1.5 %5 MW

11.6 %58 MW

2.7 %7 MW

11.8 %59 MW

2.1 %6 MW

15.8 %70 MW

2.0 %6 MW
MF Renter LMI10%10%16%13%22%18%MF Renter LMI44%46%42%56%58%54%MF Renter LMI41%43%37%55%59%54%MF Renter LMI51%52%40%72%67%47%

5.2 %39 MW

0.8 %3 MW
MF Renter LMI5%12%11%0%11%11%
Optimistic outlook for providing renter and LMI customer solutions starting early 2025 Optimistic outlook on enhanced community outreach and support, along with improved permitting processes starting early 2025 Net energy metering at retail ratesFederal and stateS0Business as UsualPersistAt the Current Level Evaluate adoption strategiesReferenceHypothetical Feasibility PersistAt the Current Level

10.0 %48 MW

10.0 %10 MW
MF Renter LMI51%54%53%92%93%93%
To achieve the goal, utility interventions are necessary to accelerate and further promote adoption.

Enhancing utility support alone can boost solar adoption to reach 10% adoption by 2030 without further utility interventions, but has limited impact on promoting battery storage adoption.Utility incentives and virtual solar solutions are needed in reaching the adoption target along with improving utility support. Positive but still limited impact on storage adoption.Improving NEM equity with reasonable upfront incentives for MF LMI/DAC customers could also work, if implemented along with improving utility support. Positive but still limited impact on storage adoption.Maintaining current NEM with strong (lower but broader) upfront incentives for all MF customers could also work, if implemented along with improving utility support. Positive but still limited impact on storage adoption.Targeted direct install alone could work as an adoption goal compliance measure, but with significant utility investment (huge cost premium compared with lower-cost utility-scale alternatives) .

159
Key Results: Additional Key Observations by ScenarioVariations in customer segments may lead to a range of outcomesSolar Storage S1Continue Current NEM
S3Balanced
S4Widespread Adoption
S5Direct Install
S0Business as Usual
At the current annual adoption rate, solar adoption is projected to reach 5.2% under business-as-usual conditions and achieve 7.4% by 2030. To achieve the goal, utility interventions are necessary to accelerate and further promote adoption.

Evaluate Adoption StrategiesReferenceHypothetical Feasibility *Additional incentives is a general representation of all types of incentives including potential upfront incentives and performance-based incentives offered by GWP. Assuming receipt of GWP incentives requires customers dispatch battery storage against utility signals to maximize community benefits.

S2Targeted LMI MF Adoption
Enhancing customer outreach and support and simplifying the permitting process can boost adoption. Without further utility interventions, adoption may fall short of the 2027 target, but it would be enough to reach 10% adoption by 2030.

Maintaining current NEM policies with strong (lower but broader) upfront incentives for all MF customers could also help reach the target, if implemented along with improving customer outreach, support, and the permitting process.

Improving NEM equity with reasonable upfront incentives for MF LMI/DAC customers could also help reach the target, if implemented along with improving customer outreach, support, and the permitting process.

Utility interventions to provide additional utility support and incentives and increase access for renter and LMI customers are needed to reach the adoption target. Unlocking adoption potential from the MF sector creates opportunities to maximize the equity of the current net metering mechanism, with co-benefits of increasing the cost-effectiveness of storage additions to customer solar systems.

At the current annual adoption rate, solar adoption is projected to reach 0.8% under business-as-usual conditions and achieve 2.0% by 2030. To achieve the goal, utility interventions are necessary to accelerate and further promote adoption.

Enhancing customer outreach and support and simplifying the permitting process alone has limited impact on promoting adoption, mainly due to the poor economic performance of adding battery storage systems to customer solar.

Additional utility incentives through direct install programs, coupled with the enhanced value proposition under NEB, promote greater adoption of customer storage (mostly SF households). Storage adoption remains insufficient to meet the adoption target by 2027, and even by 2030. This is primarily attributed to historically low adoption rates and the continued mediocre economic performance of BTM storage systems.Additional utility incentives through upfront incentives promote greater adoption of customer storage (mix of SF/MF households). While the attachment rate of storage to solar systems falls within the average range, it remains insufficient to meet the adoption target by 2027, and even by 2030. This is primarily attributed to historically low adoption rates and the continued mediocre economic performance of BTM storage systems.Additional utility incentives through upfront incentives promote greater adoption of customer storage (mostly MF households). While the attachment rate of storage to solar systems falls within the average range, it remains insufficient to meet the adoption target by 2027, and even by 2030. This is primarily attributed to historically low adoption rates and the continued mediocre economic performance of BTM storage systems.

N/AN/A

160
2027 Customer Adoption by Scenario – SolarIncluding solar-only and solar + storage systems, cumulative adoption by 2027 S1: Continue Current NEMS2: Targeted MF LMI AdoptionS3: BalancedS4: Widespread Adoption LMI: Low and Moderate IncomeMF: Multi-family
10%
12% 12%
16%
2%
5%
4%
6%
1%
5%
5%
8%
1%
6% 5%
8%
0%
2%
4%
6%
8%
10%
12%
14%
16%
18%
S1 S2 S3 S4
Total and LMI Adoption in 2027 Relative to All GWP Customers (%) Total Adoption
LMI Adoption
MF Adoption
Renter Adoption
% of Total GWP Customers

9.6%

11.7% 11.8%

15.8%

1.6%

4.9% 4.4%

6.3%

1.0%

5.1% 4.8%

8.0%

0.9%

5.3% 5.1%

8.2%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

16.0%
S1 S2 S3 S4
Adoption in 2027 Relative to All GWP Customers (%)
Total Adoption
LMI Adoption
MF Adoption
Renter Adoption
% of Total GWP Customers
Adoption Scenarios
Solar Adoption (% of Total GWP Electric Customers)
161
2027 Customer Adoption by Scenario – Battery StorageIncluding solar + storage systems, cumulative adoption by 2027 LMI: Low and Moderate IncomeMF: Multi-family

1.5%

2.7% 2.1% 2.0%

0.3%

1.4% 1.1% 1.0%

0.2%

1.5% 1.2% 1.4%

0.3%

1.5% 1.2% 1.4%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

16.0%
S1 S2 S3 S4
Adoption in 2027 Relative to All GWP Customers (%)
Total Adoption
LMI Adoption
MF Adoption
Renter Adoption
% of Total GWP Customers

1.5%

2.7%

2.1% 2.0%

0.3%

1.4% 1.1% 1.0%

0.2%

1.5% 1.2% 1.4%

0.3%

1.5% 1.2% 1.4%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

14.0%

16.0%
S1 S2 S3 S4
Adoption in 2027 Relative to All GWP Customers (%)
Total Adoption
LMI Adoption
MF Adoption
Renter Adoption
% of Total GWP Customers
S1: Continue Current NEMS2: Targeted MF LMI AdoptionS3: BalancedS4: Widespread AdoptionAdoption Scenarios Battery Storage Adoption (% of Total GWP Electric Customers) 162
Most of the examined adoption-accelerating program portfolios increase solar access•The share of customer solar adoption attributed to multifamily, renter, or LMI customers increases in most adoption scenarios due to enhanced utility support, enhanced options for renter and LMI customers, improved net metering compensation, and targeted additional incentives Reference Scenario (S0) (2023 Level)Range of Scenario Results (S1-S4) Multifamily %
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163
All examined adoption-accelerating program portfolios increase battery storage access•The share of customer battery storage adoption attributed to multifamily, renter, or LMI customers increases in all adoption scenarios due to enhanced utility support, enhanced options for renter and LMI customers, improved net metering compensation, and targeted additional incentives•Although access improves, storage adoption does not meet the target due to high upfront costs and minor bill savings Range of Scenario Results (S1-S4)
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164
Adoption scenarios project theoretical upper bounds for adoption, resulting in net ratepayer costs and rate impacts 0%
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•The adoption scenarios project upper bounds for solar adoption by 2027. The adoption level results will be further limited by implementation barriers, customer adoption behavior, and other financial and non-economic barriers that customers face.•All proposed strategies impose more costs on GWP ratepayers and lead to further increases in retail rates.•There are alternatives to current NEM that can still promote local solar and storage but also reduce costs to GWP ratepayers.

Reference Scenario (S0)Range of Scenario Results (S1-S4) Solar Adoption (%)Storage Adoption (%)Net Ratepayer Costs ($)Rate Impacts (¢/kWh)CumulativeCumulativeAnnualCompared with rates w/o post-2023 solar and storage Continue Current NEM (S1)
On top of other sources of anticipated rate growthYear
165
All examined program portfolios require significant utility investments, increasing rates and bills for all GWP customers•Across all adoption scenarios, retail rates are anticipated to increase between 6% and 11% by 2030 due to solar and storage programs on top of other anticipated sources of rate growth•This means that the average LMI customer will pay between $4 and $6 more per month on electricity, or $48 to $72 per year Range of Scenario Results (S1-S4)
Rate Impacts (¢/kWh)Rate Impact (%)Avg. LMI Bill Impact ($/month)

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Compared with rates w/o post-2023 solar and storageCompared with rates w/o post-2023 solar and storageCompared with monthly bills w/o post-2023 solar and storage Reference Scenario (S0) (2023 Level)YearYearYear
Section 7.4Modeling Approach, Inputs, and Assumptions
167
ÊE3 developed prototypical customer shapes using NREL ResStock and ComStock and leveraged work with the CPUC and LBNL on modeling flexible loadsÊE3 performed DER optimal dispatch simulation through its RESTORE model and identified appropriate rate signals to guide dispatch providing grid value E3 quantified the dispatchable capacity and demand reduction potential of DERs for valuation and rate design considerations A broad range of technologies
Market prices, utility ratesOptimal dispatchMarket revenues or customer savings

RESTORE

168
E3 utilized its in-house DER toolkit (RESTORE) to estimate DER adoption forecasts DER Portfolio
Energy Efficiency Measures & Voltage Optimization
Customer-Sited PV
Smart Water Heater
Smart HVAC
Managed EV Charging
Storage
Fossil Generator(e.g., fuel cell)
Load Shedding DR
20°
A broad range of DER
Resource planning data, utility ratesOptimal dispatchAdoption forecast

RESTORE
Output designed for utility and regulatory commission consideration including Standard Practice ManualA public version of RESTORE without the IDSM feature can be found here:CEC Docket Log 19-MISC-04, https://efiling.energy.ca.gov/Lists/DocketLog.aspx?docketnumber=19-MISC-04 The Integrated Demand Side Management (IDSM) feature of E3’s RESTORE model can be used to predict adoption of a range of DER technologies. For this study, E3 used it to predict solar and storage adoption for GWP customers.

LegendDispatchable for energy servicesDispatchable while providing non-energy servicesNon-dispatchable 169
RESTORE estimates DER adoption based on dispatch and cost-effectivenessÊAdoption•Impacts of rate scenarios and sensitivities on cumulative adoption ÊCosts & Benefits•Detailed costs and benefits shedding light on how economics affect consumer adoption ÊDER Dispatch / Customer Load Impact•How DER affects BTM customer net load under different scenarios Adoption
Costs & Benefits
Customer Load ImpactHour 123456789101112131415161718192021222324JanFebMarAprMayJunJulAugSepOctNovDec

170
GWP-Customized Workflow of the IDSM Feature of RESTORE
Incentive Program(s)Customer Benefits EvaluationCustomer Costs EvaluationAdoption Behavior SimulationSystem Benefits EvaluationBenefit Cost Analysis RESTORE Integrated Demand-Side Management (IDSM) Tool Flowchart ÊState and federal upfront incentivesÊScenario-specific utility incentives ÊNet present value (NPV) calculation of customer bill savingsÊVarying rate designs lead to different bill savings potential ÊNPV of project lifetime costs (upfront and recurring)ÊTechnology costs and trajectories based on NREL ATB data ÊCustomer economics (benefit / cost ratio) predict adoption from 2025 to 2030 ÊSolar and storage system dispatch used to evaluate GWP system-wide avoided costs and emissions reductions IDSM model outputs feed into the system-wide Benefit Cost Analysis 171
RESTORE deploys bass diffusion adoption modeling considering DER cost-effectiveness ÊIDSM utilizes classic bass diffusion modelÊAn empirical market share model to determine the long-run market equilibrium of customer adoption•The relationship between economic attractiveness and maximum market share based on payback period or benefit-cost ratioÊA bass diffusion model explains the time dynamics and adoption path to thisequilibrium •The pace of adoption is controlled by year-to-year changes in economics•Adoption will be accelerated if economics substantially improve Incentive Program(s)Customer Benefits EvaluationCustomer Costs EvaluationAdoption Behavior SimulationSystem Benefits EvaluationBenefit Cost Analysis 172
More than a dozen customer segments were captured in E3’s analysisÊIdentified 18 customer segments to represent diversity by customer sector, ownership, and income•Enabled segmentation of MF , renter, and LMI/DAC customers for equity analysisÊSegmented into three customer sectors•SF , MF , and C&IÊClassified into six building types•SF: Single-Family•MF: Multi-Family Low-Rise vs. High-Rise•C&I: Small, Medium, LargeÊDistinguished by two ownership statuses•Owner vs. TenantÊCategorized by two income classes•LMI and non-LMI (general market) Customer Segmentation in RESTORE ModelingCustomer No.Customer SectorBuilding TypeOwnership StatusIncome Class1SFSingle-FamilyOwnerLMI2SFSingle-FamilyOwnerNon-LMI3SFSingle-FamilyTenantLMI4SFSingle-FamilyTenantNon-LMI5MFMulti-Family Low-RiseOwnerLMI6MFMulti-Family Low-RiseOwnerNon-LMI7MFMulti-Family Low-RiseTenantLMI8MFMulti-Family Low-RiseTenantNon-LMI9MFMulti-Family High-RiseOwnerLMI10MFMulti-Family High-RiseOwnerNon-LMI11MFMulti-Family High-RiseTenantLMI12MFMulti-Family High-RiseTenantNon-LMI13C&ISmallOwnerN/A14C&ISmallTenantN/A15C&IMediumOwnerN/A16C&IMediumTenantN/A17C&ILargeOwnerN/A18C&ILargeTenantN/A 173
Premises of a Successful Adoption PlanÊStrong Outreach, Education, Support: assumed the level of outreach is not a constraint, and comprehensive outreach and educational campaigns are present which enhance awareness and empower residents to make informed decisions with understanding of the underlying economics.ÊImproved Permitting Process: assumed permitting process is not a constraint, and a faster, easier, and scalable permitting, interconnection, and approval process to facilitate smoother installations is present.ÊIntelligible Program Design: assumed information access and intelligibility of program design is not a constraint for adoption.ÊAddressing Split Incentives: modeled the split incentive assuming renters have a significantly higher discount rate than owners in cases where split incentives persist. A deep dive into what programs could mitigate split incentives is presented later.

Other Model AssumptionsÊModeling LMI Customers: LMI customers were assumed to have higher hurdle rates for DER economics, necessitating higher investment decision thresholds.ÊAdoption Sequencing: customers were assumed to consider adopting solar first, followed by potential adoption of storage. Only customers with existing solar installations would consider adding storage.ÊInterconnection Charges: charges related to interconnection are already accounted for in solar installation costs.ÊBuilding Stock: solar and storage mandate estimates were estimated via downstream analysis. Customer counts were assumed to remain static, with no changes in the building stock. New construction was considered separately (see next slide).ÊBuilding Electrification: the model assumed stable customer load profiles. Sensitivity of building electrification can be done as sensitivities in later stages.

Key model assumptions are important to note for accurate interpretation of adoption forecastsSeveral prerequisites are fundamental for a successful adoption plan. For the purposes of this study, E3 made the following assumptions to assume the existence of these premises. For instance, the model assumes that customers have complete information about the program, its costs and benefits, and will make economic decisions accordingly, along with other key assumptions.

Section 7.5Detailed Model Results: Solar & Battery Storage 175
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Glendale New Privately Owned Housing Unit Authorizations Single-family Units (Historical)Single-family Units (Forecast - Exponential Smoothing) U.S. Census Bureau Building Permits Survey, # of Units, Single-family Forecast
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Glendale New Privately Owned Housing Unit Authorizations Multifamily Units (Historical)Multifamily Units (Forecast - Exponential Smoothing) U.S. Census Bureau Building Permits Survey, # of Units, Multi-family Forecast
Building code-compliant solar and storage adoption from new construction contributes to achieving the adoption targetÊGlendale has a local “reach code” that adopts the local amendments to the 2022 California Energy Code (Title 24, Part 6, and Part 11) that provide local, cost-effective standards for new residential, non-residential, and hotel and motel buildings that exceed the minimum standards of the 2022 California Energy Code and 2022 California Green Building Standards Code. Requirements vary based on locations and building types, with waivers and exceptions available as needed.

ÊFor the purposes of this study, future growth in residential new construction was estimated utilizing building permit survey data from 1990 to 2022.•Single-family: 80 units/yr (0.33% annual growth)•Multi-family: 290 units/yr (0.54% annual growth)•Commercial & Industrial: 63 units/yr (0.48% annual growth)** Single-family: 80 units/yr*
Multi-family: 290 units/yr*
•The 2023 values were estimated by applying exponential smoothing to historical data from 1990 to 2022, employing a short-term time series forecasting method. Future annual growth was assumed to mirror the 2023 forecast as a conservative estimate.** Commercial and Industrial new construction was estimated by mirroring the overall new construction growth rate from the residential sector, multiplied by 13,184 units reported in the GWP 2023 Annual Report.

0.33% annual growth of 24,000 customers

0.54% annual growth of 54,000 customers
Solar•SF: All newly constructed single-family buildings must have new solar PV systems/modules (Title 24).•MF, C&I: Install a PV system that offsets 100% of building electricity, or at least covers 50% of gross roof space area (Reach Code).For the purposes of this study, E3 assumed SF, MF, and C&I new construction comes with PV systems at average PV capacity accounting for roof and size limits.

Battery Storage•SF: No requirement.•MF High-rise, C&I: All buildings required to have solar PV must also have battery storage (Title 24).

For the purposes of this study, E3 assumed MF and C&I's new construction includes a 2-hour battery storage size to cover customer annual peak demand. 176
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ÊBy the end of 2027, building code-compliant customer solar adoption could have the potential to reach 1,700+ units since the start of 2024.•Approximately 20% of the 10% customer penetration target•For the purposes of this study, E3 assumed SF , MF , and C&I new construction comes with PV systems at average PV capacity accounting for roof and size limits Building code-compliant solar and storage adoption from new construction will be importantÊBy the end of 2027, building code-compliant customer storage adoption could have the potential to reach 1,400+ units since the start of 2024.•Approximately 15% of the 10% customer penetration target•For the purposes of this study, E3 assumed MF and C&I's new construction includes a 2-hour battery storage size to cover customers' annual peak demand *Requirements for solar installations may vary based on location and building type. Waivers and exceptions are available as needed. In this study, a 90% derating factor was applied to represent exceptions and waivers. This factor accounts for uncertainties in specific building designs. It is crucial to note that this assumption requires further study to validate its accuracy. 1559 1277
Account for 90% waiver and exception derate*Account for 90% waiver and exception derate* 177
2,924 5,023 7,241
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GWP Customer Solar Penetration -Business-as-Usual (BAU) Scenario New Constr ucti on
Existing Buildings - C&I
Existing Buildings - MF
Existing Buildings - SF
City Council Target
# of GWP Electric Service Customers
12%12%12%
2023 2027 2030
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OwnerRenter
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2023 2027 2030
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Non-LMILMI
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SFMFCom

28.2 39.0 50.4
2023 2027 2030
Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction Customer Solar and Storage Adoption Modeling ResultsScenario 0 – Business-as-Usual (Solar) This scenario reflects current GWP policies without new incentive programs and without improved outreach, support, and improved permitting process. The adoption forecast was developed using historical adoption data by customer segment, calibrated through a Bass Diffusion curve.ÊThis scenario is based on:•Stacking of available federal, state funding and applicable tax credits•NEM at retail rate without virtual net metering or off-site solar programs•No additional utility incentives and follow current feed-in-tariff program rules•No additional enhanced community outreach and support, along with improved permitting processes starting early 2025•Split incentive issue for tenants persists throughout the analysis periodÊExpected adoption level:•2027 customer penetration: 5.2%•2030 customer penetration: 7.4% •Nameplate capacity: 39 MW by 2027, and 50 MW by 2030ÊKey takeaways:•At the current rate of annual adoption, solar adoption is projected to reach 5.2% under business-as-usual conditions and achieve 7.4% by 2030. To achieve the goal, utility interventions are necessary to accelerate and further promote adoption.•Adoption is dominated by owner-occupied, single-family, non-LMI households

178
Customer Solar and Storage Adoption Modeling ResultsScenario 0 – Business-as-Usual (Battery Storage)This scenario reflects current GWP policies without new incentive programs and without improved outreach, support, and improved permitting processes. The adoption forecast was developed using historical adoption data by customer segment, calibrated through a Bass Diffusion curve.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEM at retail rate without virtual net metering or off-site solar programs•No additional utility incentives and follow current feed-in-tariff program rules•No additional enhanced community outreach and support, along with improved permitting processes starting in early 2025•Split incentive issue for tenants persists throughout the analysis periodÊExpected adoption level:•2027 customer penetration: 0.8% (14% attachment rate)•2030 customer penetration: 2.0% (27% attachment rate)•Nameplate capacity: 3 MW by 2027, and 6 MW by 2030ÊKey takeaways:•At the current rate of annual adoption, solar adoption is projected to reach 0.8% under business-as-usual conditions and achieve 2.0% by 2030. To achieve the goal, utility interventions are necessary to accelerate and further promote adoption.•Adoption is dominated by owner-occupied, single-family, non-LMI households•Notable adoption mandate observed in new construction 185 725 1,968
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GWP Customer Storage Penetration -Business-as-Usual (BAU) Scenario New Constr ucti onExisting Buildings - C&I
Existing Buildings - MFExisting Buildings - SFCity Council Target # of GWP Electric Service Customers
11%11%11%
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OwnerRenter
11%11%11%
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Non-LMILMI
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SF vs MF vs C&I
SFMFCom

1.3 2.8 6.2
2023 2027 2030
Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction 179
Customer Solar and Storage Adoption Modeling ResultsScenario 1 – Continue Current NEM (Solar) This scenario reflects current GWP policies without new incentive programs but with improved outreach, support, and permitting processes.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEM at retail rate without virtual net metering or off-site solar programs•No additional utility incentives and follow current feed-in-tariff program rules•Optimism regarding enhanced community outreach and support, along with improved permitting processes starting in early 2025•Split incentive issue for tenants persists throughout the analysis periodÊExpected adoption level:•2027 customer penetration: 9.6%•2030 customer penetration: 15.2% •Nameplate capacity: 60 MW by 2027, and 90 MW by 2030ÊKey takeaways:•Enhancing customer outreach and support and simplifying the permitting process can boost adoption. Without further utility interventions, adoption may fall short of the 2027 target, but it would be enough to reach 10% adoption by 2030.•Under current NEM, there is stable growth in SF adoption, particularly among owner-occupied, non-LMI households•Limited MF growth under current NEM due to split incentives, stemming from ownership dynamics•The C&I sector has fewer customers but larger average installations, making it a key contributor to reaching the 100 MW DER capacity target.•Notable adoption mandate observed in new construction S1 adoption analysis does not differentiate existing buildings and new construction 180
Customer Solar and Storage Adoption Modeling ResultsScenario 1 – Continue Current NEM (Battery Storage)This scenario reflects current GWP policies without new incentive programs but with improved outreach, support, and permitting processes.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEM at retail rate without virtual net metering or off-site solar programs•No additional utility incentives and follow current feed-in-tariff program rules•Optimism regarding enhanced community outreach and support, along with improved permitting processes starting in early 2025•Split incentive issue for tenants persists throughout the analysis periodÊExpected adoption level:•2027 customer penetration: 1.5% (16% attachment rate)•2030 customer penetration: 2.5% (16% attachment rate)•Nameplate capacity: 5 MW by 2027, and 8 MW by 2030ÊKey takeaways:•Enhancing customer outreach and support and simplifying the permitting process alone has limited impact on promoting adoption, mainly due to the poor economic performance of adding battery storage systems to customer solar.–Substantial upfront costs–Comparatively diminished benefits including lack of energy arbitrage benefits (low TOU participation, symmetric NEM rate schedule, etc.) and less quantifiable resiliency benefits•Adoption is dominated by owner-occupied, single-family, non-LMI households•Most of the new adoption will come from building code-compliant system installation from new construction 185 1,490 2,445
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GWP Customer Storage Penetration -No New Program Scenario New Constr ucti onExisting Buildings - C&IExisting Buildings - MFExisting Buildings - SFCity Council Target # of GWP Electric Service Customers
11%22%22%
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OwnerRenter
11%18%18%
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LMI vs Non-LMI
Non-LMILMI
0% 13%13%
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SF vs MF vs C&I
SFMFCom

1.3 5.1 8.0
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Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction 181
Customer Solar and Storage Adoption Modeling ResultsScenario 2 – Targeted LMI MF Adoption (Solar) This scenario aims to reach as much adoption as possible while maintaining high standards for equitable implementation. Focus on minimal cost shifting and promoting LMI/DAC adoption via direct install programs.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEB and VNEB programs are priced at avoided costs starting early 2025•Implementation of direct install program targeting MF LMI/DAC starting in early 2025•Optimistic outlook on enhanced community outreach and support, as well as improved permitting processes starting in early 2025•Assume split incentives are completely resolved starting in early 2025ÊExpected adoption level:•2027 customer penetration: 11.6%•2030 customer penetration: 20.8% •Nameplate capacity: 58 MW by 2027, and 88 MW by 2030ÊKey takeaways:•Utility interventions to provide additional incentives and resolve split incentives are needed to reach the adoption target, along with improving customer outreach, support, and the permitting process. Unlocking adoption potential from the MF sector creates opportunities to maximize the equity of the current net metering mechanism, with co-benefits of increasing the cost-effectiveness of storage additions to customer solar systems (discussed in the next slide).•Lower SF growth under NEB due to lower export compensation rate, which improves equity by reducing cost shifts to non-adopters•With solutions to split incentives and direct install programs targeted at MF LM/DAC households, the multifamily sector has dramatic adoption growth since 2025, and solar access expands outside single-family and becomes balanced

182
Customer Solar and Storage Adoption Modeling ResultsScenario 2 – Targeted LMI MF Adoption (Battery Storage)This scenario aims to reach as much adoption as possible while maintaining high standards for equitable implementation. Focus on minimal cost shifting and promoting LMI/DAC adoption via direct install programs.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEB and VNEB programs are priced at avoided costs starting in early 2025•Implementation of a direct install program targeting MF LMI/DAC starting in early 2025•Optimistic outlook on enhanced community outreach and support, as well as improved permitting processes starting in early 2025•Assume split incentives are completely resolved starting in early 2025ÊExpected adoption level:•2027 customer penetration: 2.7% (23% attachment rate)•2030 customer penetration: 4.4% (21% attachment rate)•Nameplate capacity: 7 MW by 2027, and 11 MW by 2030ÊKey takeaways:•Additional utility incentives through direct install programs, coupled with the enhanced value proposition under NEB, promote greater adoption of customer storage (mostly SF households). While the storage attachment rate to solar systems falls within the state average range (6%-19% by income level), it remains insufficient to meet the adoption target by 2027 and even by 2030. This is primarily attributed to historically low adoption rates and the continued mediocre economic performance of BTM storage systems.•With the export rate being lower than the import rate under NEB/VNEB, storage systems are better off and have a higher value in maximizing household self-consumption, thus observing adoption growth from the residential and commercial sectors•MF growth increased as expected because of the targeted LMI MF direct install program that covers the initial upfront cost 185 2,562 4,277
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GWP Customer Storage Penetration -Targeted MF LMI Adoption Scenario New Constr ucti onExisting Buildings - C&I
Existing Buildings - MFExisting Buildings - SFCity Council Target # of GWP Electric Service Customers
11%
58%58%
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Owner vs Renter
OwnerRenter
11%
54%54%
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Non-LMILMI
0%
56%56%
2023 2027 2030
SF vs MF vs C&I
SFMFCom

1.3 6.8 10.9
2023 2027 2030
Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction 183
Customer Solar and Storage Adoption Modeling Results Scenario 3 – Balanced (Solar) This scenario aims to reach a balance between S2 and S4, with a focus on increasing customer adoption while reducing cost shift, supplemented with MF LMI/DAC upfront incentives as needed.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEB/VNEB programs priced at avoided costs with adders to achieve 7-year payback periods for solar to promote adoption starting in early 2025•Introduction of additional 7-yr payback incentives for solar and storage specifically aimed at MF LMI/DAC households starting early 2025•Optimistic anticipation of enhanced community outreach and support, coupled with improved permitting processes starting in early 2025•Assume split incentives are completely resolved starting in early 2025ÊExpected adoption level:•2027 customer penetration: 11.8%•2030 customer penetration: 22.0% •Nameplate capacity: 59 MW by 2027, and 92 MW by 2030ÊKey takeaways:•Improving NEM equity with reasonable upfront incentives for MF LMI/DAC customers could also help reach the target, if implemented along with improving customer outreach, support, and the permitting process.•Slightly lower SF growth under NEB (with adder) due to a slightly lower export compensation rate, which improves equity by reducing cost shifts to non-adopters. Encourages more adoption than S2 (Targeted MF LMI Adoption) because an adder to promote adoption is included.•With solutions to split incentives and upfront incentive programs targeted at MF LMI/DAC households, the MF sector has dramatic adoption growth since 2025. This upfront incentive program is less deep than the direct install program in S1 and less broad than S3 for all MF households, so there is lower adoption but enough to achieve the goal and expand solar access outside of the SF sector.

184
Customer Solar and Storage Adoption Modeling Results Scenario 3 – Balanced (Battery Storage)This scenario aims to reach a balance between S2 and S4, with a focus on increasing customer adoption while reducing cost shifts, supplemented with MF LMI/DAC upfront incentives as needed.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEB/VNEB programs priced at avoided costs with adders to achieve 7-year payback periods for solar to promote adoption starting in early 2025•Introduction of additional 7-yr payback incentives for solar and storage specifically aimed at MF LMI/DAC households starting early 2025•Optimistic anticipation of enhanced community outreach and support, coupled with improved permitting processes starting in early 2025•Assume split incentives are completely resolved starting in early 2025ÊExpected adoption level:•2027 customer penetration: 2.1% (18% attachment rate)•2030 customer penetration: 3.4% (16% attachment rate)•Nameplate capacity: 6 MW by 2027, and 9 MW by 2030ÊKey takeaways:•Additional utility incentives through upfront incentives promote greater adoption of customer storage (mix of SF/MF households). While the storage attachment rate to solar systems falls within the average range, it remains insufficient to meet the adoption target by 2027 and even by 2030. This is primarily attributed to historically low adoption rates and the continued mediocre economic performance of BTM storage systems.•With the export rate slightly lower than the import rate under NEB/VNEB, storage systems are slightly better off and have higher value in maximizing household self-consumption, thus observing adoption growth from the residential and commercial sectors•With additional upfront incentives for MF LMI/DAC households, more MF battery systems are expected to come online. This helps improve the equity distribution of storage access, though total adoption is still minimal due to customer storage's mediocre performance. 185 2,019 3,334
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GWP Customer Storage Penetration -Balanced Scenario
New Constr ucti onExisting Buildings - C&I
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11%
59%66%
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11%
54%62%
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Non-LMILMI
0%
55%64%
2023 2027 2030
SF vs MF vs C&I
SFMFCom

1.3 5.9 9.2
2023 2027 2030
Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction 185
Customer Solar and Storage Adoption Modeling Results Scenario 4 – Widespread Adoption (Solar) This scenario aims to reach the adoption goal with an emphasis on customer-sited solar and storage. Focus on maximizing adoption with supplemental upfront incentives as needed.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits•NEM and VNEM are both set at retail rates starting in early 2025•Introduction of additional 5-yr payback incentives specifically aimed at MF households starting early 2025•Optimistic anticipation of enhanced community outreach and support, coupled with improved permitting processes starting in early 2025•Assume split incentives are completely resolved starting in early 2025ÊExpected adoption level:•2027 customer penetration: 15.8%•2030 customer penetration: 30.4% •Nameplate capacity: 70 MW by 2027, and 119 MW by 2030ÊKey takeaways:•Maintaining current NEM policies with strong (lower but broader) upfront incentives for all MF customers could also help reach the target, if implemented along with improving customer outreach, support, and the permitting process.•SF growth is forecasted to be the same as S1 since it is also under the current NEM at retail rates•With solutions to split incentives and upfront incentives targeted at all MF households, the multi-family sector has dramatic adoption growth since 2025, and solar access expands outside of the single-family sector and becomes balanced.

186
Customer Solar and Storage Adoption Modeling ResultsScenario 4 – Widespread Adoption (Battery Storage)This scenario aims to reach the adoption goal with an emphasis on customer-sited solar and storage. Focus on maximizing adoption with additional upfront incentives as needed.ÊThis scenario is based on:•Stacking of available federal and state funding and applicable tax credits• NEM and VNEM are both set at retail rates starting in early 2025•Introduction of additional 5-yr payback incentives specifically aimed at MF households starting early 2025•Optimistic anticipation of enhanced community outreach and support, coupled with improved permitting processes starting in early 2025•Assume split incentives are completely resolved starting in early 2025ÊExpected adoption level:•2027 customer penetration: 2.0% (13% attachment rate)•2030 customer penetration: 3.4% (11% attachment rate)•Nameplate capacity: 6 MW by 2027, and 9 MW by 2030ÊKey takeaways:•Additional utility incentives through upfront incentives promote greater adoption of customer storage (mostly MF households). While the storage attachment rate to solar systems falls within the average range, it remains insufficient to meet the adoption target by 2027 and even by 2030. This is primarily attributed to historically low adoption rates and the continued mediocre economic performance of BTM storage systems.•SF growth is forecasted to be the same as S1 since it is also under the current NEM at retail rates where storage systems do not provide the value-add of maximizing self-consumption.•With the additional upfront incentives targeted at the MF sector, more MF battery systems are expected to come online. This helps improve the equity distribution of storage access, though total adoption is still minimal due to mediocre customer storage performance. 185 1,941 3,343
-
5,000
10,000
15,000
20,000
25,000
30,000
35,000
20232024202520262027202820292030
GWP Customer Storage Penetration -Widespread Adoption Scenario New Constr ucti onExisting Buildings - C&IExisting Buildings - MFExisting Buildings - SFCity Council Target # of GWP Electric Service Customers
11%
67%76%
2023 2027 2030
Owner vs Renter
OwnerRenter
11%47%53%
2023 2027 2030
LMI vs Non-LMI
Non-LMILMI
0%
72%83%
2023 2027 2030
SF vs MF vs C&I
SFMFCom

1.3 5.5 8.7
2023 2027 2030
Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction 187
ÊAs a hypothetical scenario, scenario 5 explores the feasibility and cost implications of a hypothetical GWP Direct Install Program covering upfront costs of solar and storage (net of available federal IRA tax credits) to achieve 10% adoption of each by 2027 focusing on multi-family, renter, and low- to moderate-income customers. ÊEstimates build on the Business as Usual (Scenario 0) forecast and calculate the incremental system installations needed to reach the City Council Targets. ÊLaunching a direct install program would incur an estimated cost of $48 million for a program period of 2025-2027, covering upfront expenses alone (net of federal and state subsidies). This cost estimate does not cover NEM compensation for these systems which will be costly in the long run.

Customer Solar and Storage Adoption Modeling Results Scenario 5 – Direct Install Adoption (Solar and Battery Storage) Utility Upfront Costs of S5 Direct Install These systems were allocated to the “Multi-family, Renter, Low- and Moderate-Income” customer types within the model.This was intended to increase access to customers historically excluded from solar and storage adoption. It is also more cost-effective from the utility program perspective, as it involves smaller system sizes per customer and allows multiple customers to benefit from installing a single system. $25,121,798
$11,881,774 $11,421,279
$-
$3, 000,000
$6, 000,000
$9, 000,000
$12, 000,000
$15, 000,000
$18, 000,000
$21, 000,000
$24, 000,000
$27, 000,000
2023 2024 2025 2026 2027
Ad ditional Storage
Solar Only
188
185 261 367 517 725 - -
4,402
6,670
8,900
-
2,0 00
4,0 00
6,0 00
8,0 00
10, 000
12, 000
2023 2024 2025 2026 2027
Ba seline Adoption For ecast Di rect Installations
2,924 3,364 3,859 4,411 5,023
-
-
2,465
3,552
4,602
-
2,0 00
4,0 00
6,0 00
8,0 00
10, 000
12, 000
2023 2024 2025 2026 2027
Ba seline Adoption For ecast Di rect Installations
Customer Solar and Storage Adoption Modeling Results Scenario 5 – Direct Install Adoption (Solar and Battery Storage) Solar AdoptionStorage Adoption
# of Customers
# of Customers
Implementing direct installation of new solar systems for customers who have not previously installed solarImplementing direct installation of storage for existing solar systems and bundling it with new solar installations 189
2,924
9,625 11,843
-
5,000
10,000
15,000
20,000
25,000
30,000
35,000
20232024202520262027202820292030
GWP Customer Solar Penetration -Direct Install Scenario New Constr ucti on
Existing Buildings - C&IExisting Buildings - MF
Existing Buildings - SFCity Council Target
# of GWP Electric Service Customers
12%
54%46%
2023 2027 2030
Owner vs Renter
OwnerRenter
11%
53%45%
2023 2027 2030
LMI vs Non-LMI
Non-LMILMI
5%
51%42%
2023 2027 2030
SF vs MF vs C&I
SFMFCom

28.2 47.5 58.9
2023 2027 2030
Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction Customer Solar and Storage Adoption Modeling Results Scenario 5 – Direct Install Adoption (Solar and Battery Storage) 185
9,625 10,867
-
5,000
10,000
15,000
20,000
25,000
30,000
35,000
20232024202520262027202820292030
GWP Customer Storage Penetration -Direct Install Scenario New Constr ucti onExisting Buildings - C&IExisting Buildings - MFExisting Buildings - SFCity Council Target # of GWP Electric Service Customers
11%
93%84%
2023 2027 2030
Owner vs Renter
OwnerRenter
11%
93%84%
2023 2027 2030
LMI vs Non-LMI
Non-LMILMI
0%
92%82%
2023 2027 2030
SF vs MF vs C&I
SFMFCom

1.3 9.9 13.3
2023 2027 2030
Nameplate Capacity (MW)
*Excluding newconstruction *Excluding newconstruction *Excluding newconstruction Section 7.6 Detailed Model Results: Utility Incentives & Bill Savings 191
Customer Solar Bill SavingsBuilding Type Ownership
Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.26 $0.13 $0.18 $0.26
Single-Family Tenant Non-LMI $0.27 $0.16 $0.20 $0.27
Single-Family Owner LMI $0.27 $0.13 $0.17 $0.27
Single-Family Owner Non-LMI $0.28 $0.16 $0.20 $0.28
Multi-Family Low-Rise Tenant LMI $0.23 $0.12 $0.16 $0.23 Multi-Family Low-Rise Tenant Non-LMI $0.24 $0.15 $0.18 $0.24 Multi-Family Low-Rise Owner LMI $0.24 $0.09 $0.15 $0.24 Multi-Family Low-Rise Owner Non-LMI $0.24 $0.15 $0.19 $0.24 Multi-Family High-RiseTenant LMI $0.23 $0.13 $0.17 $0.23 Multi-Family High-RiseTenant Non-LMI $0.24 $0.16 $0.19 $0.24 Multi-Family High-RiseOwner LMI $0.23 $0.11 $0.16 $0.23 Multi-Family High-RiseOwner Non-LMI $0.26 $0.19 $0.22 $0.26 C&I Small Tenant N/A $0.25 $0.14 $0.14 $0.25
C&I Small Owner N/A $0.25 $0.14 $0.14 $0.25
C&I Medium Tenant N/A $0.15 $0.11 $0.11 $0.15
C&I Medium Owner N/A $0.15 $0.11 $0.11 $0.15
C&I Large Tenant N/A $0.13 $0.11 $0.11 $0.13
C&I Large Owner N/A $0.13 $0.12 $0.12 $0.13
Building Type Ownership
Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.32 $0.18 $0.23 $0.32
Single-Family Tenant Non-LMI $0.33 $0.21 $0.25 $0.33
Single-Family Owner LMI $0.33 $0.17 $0.22 $0.33
Single-Family Owner Non-LMI $0.34 $0.21 $0.25 $0.34
Multi-Family Low-Rise Tenant LMI $0.28 $0.16 $0.21 $0.28 Multi-Family Low-Rise Tenant Non-LMI $0.29 $0.19 $0.23 $0.29 Multi-Family Low-Rise Owner LMI $0.29 $0.14 $0.19 $0.29 Multi-Family Low-Rise Owner Non-LMI $0.30 $0.20 $0.23 $0.30 Multi-Family High-RiseTenant LMI $0.28 $0.17 $0.21 $0.28 Multi-Family High-RiseTenant Non-LMI $0.29 $0.20 $0.24 $0.29 Multi-Family High-RiseOwner LMI $0.28 $0.15 $0.20 $0.28 Multi-Family High-RiseOwner Non-LMI $0.32 $0.24 $0.27 $0.32 C&I Small Tenant N/A $0.31 $0.19 $0.19 $0.31
C&I Small Owner N/A $0.31 $0.19 $0.19 $0.31
C&I Medium Tenant N/A $0.18 $0.14 $0.14 $0.18
C&I Medium Owner N/A $0.18 $0.14 $0.14 $0.18
C&I Large Tenant N/A $0.16 $0.15 $0.15 $0.16
C&I Large Owner N/A $0.16 $0.15 $0.15 $0.16
2025 Bill Savings ($/kWh)2030 Bill Savings ($/kWh)
S1Continue Current NEMS3BalancedS4Widespread AdoptionNet energy metering at retail rates Net energy metering at retail ratesNet energy billing above avoided costs but below retail ratesS2Targeted LMI MF AdoptionNet energy billing at avoided costsS0 and S5 represent bookend scenarios derived from standalone, simplified back-of-envelope calculations, intended to provide a broad estimate of magnitude. Since these scenarios were not processed through the detailed adoption modeling (RESTORE), they do not include results related to bill savings or utility incentives. 192
Customer Storage Bill Savings2025 Bill Savings ($/kWh)2030 Bill Savings ($/kWh) Building Type Ownership
Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.00 $0.26 $0.18 $0.00
Single-Family Tenant Non-LMI $0.00 $0.27 $0.20 $0.00
Single-Family Owner LMI $0.00 $0.26 $0.19 $0.00
Single-Family Owner Non-LMI $0.00 $0.28 $0.21 $0.00
Multi-Family Low-Rise Tenant LMI $0.00 $0.08 $0.06 $0.00 Multi-Family Low-Rise Tenant Non-LMI $0.00 $0.24 $0.17 $0.00 Multi-Family Low-Rise Owner LMI $0.00 $0.10 $0.07 $0.00 Multi-Family Low-Rise Owner Non-LMI $0.00 $0.24 $0.17 $0.00 Multi-Family High-RiseTenant LMI $0.00 $0.08 $0.06 $0.00 Multi-Family High-RiseTenant Non-LMI $0.00 $0.24 $0.17 $0.00 Multi-Family High-RiseOwner LMI $0.00 $0.10 $0.07 $0.00 Multi-Family High-RiseOwner Non-LMI $0.00 $0.26 $0.19 $0.00 C&I Small Tenant N/A $0.00 $0.25 $0.25 $0.00
C&I Small Owner N/A $0.00 $0.25 $0.25 $0.00
C&I Medium Tenant N/A $0.00 $0.14 $0.14 $0.00
C&I Medium Owner N/A $0.00 $0.14 $0.14 $0.00
C&I Large Tenant N/A $0.00 $0.12 $0.12 $0.00
C&I Large Owner N/A $0.00 $0.10 $0.10 $0.00
Building Type Ownership
Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.00 $0.26 $0.19 $0.00
Single-Family Tenant Non-LMI $0.00 $0.28 $0.21 $0.00
Single-Family Owner LMI $0.00 $0.27 $0.19 $0.00
Single-Family Owner Non-LMI $0.00 $0.29 $0.21 $0.00
Multi-Family Low-Rise Tenant LMI $0.00 $0.05 $0.03 $0.00 Multi-Family Low-Rise Tenant Non-LMI $0.00 $0.23 $0.16 $0.00 Multi-Family Low-Rise Owner LMI $0.00 $0.08 $0.05 $0.00 Multi-Family Low-Rise Owner Non-LMI $0.00 $0.24 $0.16 $0.00 Multi-Family High-RiseTenant LMI $0.00 $0.04 $0.03 $0.00 Multi-Family High-RiseTenant Non-LMI $0.00 $0.24 $0.17 $0.00 Multi-Family High-RiseOwner LMI $0.00 $0.07 $0.05 $0.00 Multi-Family High-RiseOwner Non-LMI $0.00 $0.24 $0.17 $0.00 C&I Small Tenant N/A $0.00 $0.26 $0.26 $0.00
C&I Small Owner N/A $0.00 $0.26 $0.26 $0.00
C&I Medium Tenant N/A $0.00 $0.13 $0.13 $0.00
C&I Medium Owner N/A $0.00 $0.13 $0.13 $0.00
C&I Large Tenant N/A $0.00 $0.10 $0.10 $0.00
C&I Large Owner N/A $0.00 $0.07 $0.07 $0.00
S1Continue Current NEMS3BalancedS4Widespread AdoptionNet energy metering at retail rates Net energy metering at retail ratesNet energy billing above avoided costs but below retail ratesS2Targeted LMI MF AdoptionNet energy billing at avoided costsS0 and S5 represent bookend scenarios derived from standalone, simplified back-of-envelope calculations, intended to provide a broad estimate of magnitude. Since these scenarios were not processed through the detailed adoption modeling (RESTORE), they do not include results related to bill savings or utility incentives. 193
Customer Solar Utility Incentives2025 Utility Incentive ($/W)2030 Utility Incentive ($/W) Building Type Ownership
Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.00 $0.00 $0.00 $0.00
Single-Family Tenant Non-LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner Non-LMI $0.00 $0.00 $0.00 $0.00
Multi-Family Low-Rise Tenant LMI $0.00 $2.59 $1.36 $1.20 Multi-Family Low-Rise Tenant Non-LMI $0.00 $0.00 $0.00 $1.18 Multi-Family Low-Rise Owner LMI $0.00 $2.59 $1.48 $1.18 Multi-Family Low-Rise Owner Non-LMI $0.00 $0.00 $0.00 $1.13 Multi-Family High-RiseTenant LMI $0.00 $2.60 $1.34 $1.20 Multi-Family High-RiseTenant Non-LMI $0.00 $0.00 $0.00 $1.17 Multi-Family High-RiseOwner LMI $0.00 $2.59 $1.42 $1.19 Multi-Family High-RiseOwner Non-LMI $0.00 $0.00 $0.00 $1.02 C&I Small Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Small Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Large Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Large Owner N/A $0.00 $0.00 $0.00 $0.00
Building Type Ownership
Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.00 $0.00 $0.00 $0.00
Single-Family Tenant Non-LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner Non-LMI $0.00 $0.00 $0.00 $0.00
Multi-Family Low-Rise Tenant LMI $0.00 $2.28 $0.72 $0.59 Multi-Family Low-Rise Tenant Non-LMI $0.00 $0.00 $0.00 $0.56 Multi-Family Low-Rise Owner LMI $0.00 $2.28 $0.84 $0.56 Multi-Family Low-Rise Owner Non-LMI $0.00 $0.00 $0.00 $0.51 Multi-Family High-RiseTenant LMI $0.00 $2.29 $0.69 $0.59 Multi-Family High-RiseTenant Non-LMI $0.00 $0.00 $0.00 $0.55 Multi-Family High-RiseOwner LMI $0.00 $2.28 $0.77 $0.58 Multi-Family High-RiseOwner Non-LMI $0.00 $0.00 $0.00 $0.37 C&I Small Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Small Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Large Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Large Owner N/A $0.00 $0.00 $0.00 $0.00
S1Continue Current NEMS3BalancedS4Widespread AdoptionNo utility incentives Guaranteed 5-yr payback for all MF customersGuaranteed 7-yr payback for all MF LMI customersS2Targeted LMI MF AdoptionDirect install for all MF LMI customersS0 and S5 represent bookend scenarios derived from standalone, simplified back-of-envelope calculations, intended to provide a broad estimate of magnitude. Since these scenarios were not processed through the detailed adoption modeling (RESTORE), they do not include results related to bill savings or utility incentives. 194
Customer Storage Utility Incentives
2025 Utility Incentive ($/W)2030 Utility Incentive ($/W)Building Type Ownership Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.00 $0.00 $0.00 $0.00
Single-Family Tenant Non-LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner Non-LMI $0.00 $0.00 $0.00 $0.00
Multi-Family Low-Rise Tenant LMI $0.00 $1.65 $1.50 $1.72 Multi-Family Low-Rise Tenant Non-LMI $0.00 $0.00 $0.00 $1.72 Multi-Family Low-Rise Owner LMI $0.00 $1.65 $1.46 $1.75 Multi-Family Low-Rise Owner Non-LMI $0.00 $0.00 $0.00 $1.72 Multi-Family High-RiseTenant LMI $0.00 $1.65 $1.50 $1.72 Multi-Family High-RiseTenant Non-LMI $0.00 $0.00 $0.00 $1.72 Multi-Family High-RiseOwner LMI $0.00 $1.65 $1.46 $1.73 Multi-Family High-RiseOwner Non-LMI $0.00 $0.00 $0.00 $1.73 C&I Small Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Small Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Large Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Large Owner N/A $0.00 $0.00 $0.00 $0.00
Building Type Ownership
Status
Income
Class S1 S2 S3 S4
Single-Family Tenant LMI $0.00 $0.00 $0.00 $0.00
Single-Family Tenant Non-LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner LMI $0.00 $0.00 $0.00 $0.00
Single-Family Owner Non-LMI $0.00 $0.00 $0.00 $0.00
Multi-Family Low-Rise Tenant LMI $0.00 $1.58 $1.49 $1.67 Multi-Family Low-Rise Tenant Non-LMI $0.00 $0.00 $0.00 $1.67 Multi-Family Low-Rise Owner LMI $0.00 $1.58 $1.43 $1.71 Multi-Family Low-Rise Owner Non-LMI $0.00 $0.00 $0.00 $1.67 Multi-Family High-RiseTenant LMI $0.00 $1.58 $1.49 $1.67 Multi-Family High-RiseTenant Non-LMI $0.00 $0.00 $0.00 $1.67 Multi-Family High-RiseOwner LMI $0.00 $1.58 $1.44 $1.68 Multi-Family High-RiseOwner Non-LMI $0.00 $0.00 $0.00 $1.69 C&I Small Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Small Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Medium Owner N/A $0.00 $0.00 $0.00 $0.00
C&I Large Tenant N/A $0.00 $0.00 $0.00 $0.00
C&I Large Owner N/A $0.00 $0.00 $0.00 $0.00
S1Continue Current NEMS3BalancedS4Widespread AdoptionNo utility incentives Guaranteed 5-yr payback for all MF customersGuaranteed 7-yr payback for all MF LMI customersS2Targeted LMI MF AdoptionDirect install for all MF LMI customersS0 and S5 represent bookend scenarios derived from standalone, simplified back-of-envelope calculations, intended to provide a broad estimate of magnitude. Since these scenarios were not processed through the detailed adoption modeling (RESTORE), they do not include results related to bill savings or utility incentives.

Section 7.7Detailed Model Results: Other DER Technologies 196
ÊFor this study, E3 modeled a single adoption scenario for electric vehicles (EVs), demand response (DR), and energy efficiency (EE) based on information from GWP’s IRPÊThese adoption forecast estimates were presented with a range in downstream analysis to account for uncertainties that were not fully addressed Key Results: Adoption Forecast for Other DERs (MW)
29 43
56 67
77 88
99 0
20 40
60 80
100
120
2024 2025 2026 2027 2028 2029 2030
Cumulative DER Capacity (MW)
Demand Response
Energy Efficiency
LDEV Managed Charging (V1G)
197
ÊFor the purposes of this study, the DR adoption forecast was based on GWP’s current plan of a 4-year residential and commercial DR program •A four-year residential and commercial DR program with an online marketplace that aims to deliver up to 10 MW of load reduction during DR events by the end of the program term•At the end of FY 2022-2023, a total of 2.5 MW was under control, representing 25% of the 4-year program goal Residential & Commercial Demand Response Adoption Forecast GWP Peak Saving Program
198
ÊFor the purposes of this study, the EV adoption forecast was derived from the GWP IRP to ensure consistency in analysis assumptionsÊGWP's IRP adopted the CEC's IEPR forecast's general assumptions without any modificationsÊE3 made the following assumptions to approximate nameplate capacity from light-duty EV (LDEV) managed charging•100% Light-duty BEV (LD-BEV)•50% L1 and 50% L2•L1 Charger: 1.4 kW•L2 Charger: 7.2 kW EV Adoption Forecast
In 2021, GWP conducted a Clean Energy Analysis with Ascend Analytics, utilizing the electric vehicle projections provided by the CEC (below) 199
ÊFor the purposes of this study, the peak savings forecast for Energy Efficiency was derived from the GWP IRP to ensure consistency in analysis assumptionsÊIn 2021, the California Municipal Utilities Association (CMUA) hired GDS Associates, Inc. to analyze and quantify the potential impact of energy efficiency in CMUA member electric service territoriesÊThe CMUA study serves as the foundation for energy efficiency targets for fiscal years 2022 through 2031, aiming to achieve 17,978 MWh per year in energy savings and 2,860 kW per year in demand response savingsÊThese figures were derived from the 10-year average of the forecasted figures developed by GDS Energy Efficiency Peak Saving Forecast
2022-2031 Forecast•Energy Saving: 17,978 MWh/yr•Peak Saving: 2,860 kW/yr•Assume peak saving already accounts for capacity contributions (i.e., after ELCC adjustment) Section 8Cost and Benefit Analysis

Section 8.1GWP Benefit-CostAnalysis Approach
202
ÊThe CPUC defines “cost-effective” and “cost-effectiveness” as a set of well-defined “cost tests in the California Standard Practice Manual (SPM)”*ÊThese cost tests provide a methodological framework to examine the benefits and costs of a particular measure from different perspectives and have become a standard in many other jurisdictions Cost-Effectiveness and Cost Test Perspectives
Cost Test Primary QuestionPCTParticipant Cost TestNet benefit for customers who adopt solar?RIMRatepayer Impact MeasureWill utility rates increase or decrease?PACTProgram Administrator Cost TestWill utility costs increase or decrease?TRCTotal Resource Cost TestNet benefits to City of Glendale?SCTSocietal Cost TestNet benefit to society as a whole?* California Standard Practice Manual 203
ÊJurisdictions have recently faced challenges considering DER cost-effectiveness as the zero GHG emission planning paradigm has emergedÊCauses for challenges for DER cost-effectiveness are:•The cost-effectiveness of many EE/DER programs is decreasing due to increasingly stringent building codes and standards, coupled with declining marginal energy costs•The cost-effectiveness of building electrification can be difficult to achieve given the high upfront costs of appliances•Increased focus on resiliency and equity for local communitiesin driving interest in DERsÊAs a result of these challenges, jurisdictions have developed strategies for DER program evaluations, which have included:•Program Buckets: Create separate categories for market transformation, policy, and equity programs, each with less stringent benefit-cost thresholds•Update Avoided Costs: Adjust to better reflect the decarbonized grid planning paradigm•Consider Additional Benefit Categories: Include societal, community, and non-energy benefits Challenges and Strategies for DER Cost-Effectiveness
204
State primary cost tests are shifting away from TRCÊMany states continue to use the TRC as a primary cost test, but fewer than 10 years ago•More states (CT, ME, MD, NH, NJ, RI) are shifting to state-specific costs tests that incorporate elements of the SCT and TRC•Many additional states have modified traditional cost tests to better fit changing needs of electrification and fuel switching (CA, CO, MA, IL, WA, WI)•Some states have multiple primary cost tests (MS, NC, OR, VA) that incorporate TRC along with UCT, PCT, and/or RIM•Not all states have a dedicated primary cost test (AL, AK, NE, ND, SC, WV)ÊSome states use different cost-effectiveness criteria for low-income EE programs Cost-Effectiveness Testing for Energy Efficiency ProgramsDatabase of Screening Practices (National Energy Screening Project, E4TheFuture)Analysis of State Approaches to Cost-Effectiveness Testing 205
ÊCurrent types of NEBs included by other jurisdictions:•Monetized: a dollar value per physical unit ofimpact for a specific NEB•Quantitative: metrics for physical units of impacts, but no dollar value•Proxy: a percent or dollar adder to account for unincluded qualitative NEBsÊMost jurisdictions and groups interested in NEBs are working on moving towards quantification as a more precise method of valuing all types of benefitsÊNot all types of cost tests can incorporate NEBs:•TRC: utility and participant NEBs only•SCT: all NEBs, including societal•UCT/PAC, PCT, RIM: no NEBs included Non-Energy Benefit (NEB) Inclusion in Cost Tests
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Database of Screening Practices (National Energy Screening Project, E4TheFuture) QuantitativeProxy (%)Monetized
Participant Non-Energy Benefits in U.S. States
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ÊGWP is not subject to the same regulatory requirements as IOUs for DER cost-effectiveness tests. However, demonstrating cost-effectiveness remains valuable for gaining City Council and public support.ÊA benefit-cost analysis can be used to assess the costs and benefits under different perspectives (participants, ratepayers, society) for GWP to achieve its 10% solar and energy storage adoption target.ÊA benefit-cost analysis can be used to inform appropriate incentive levels.•Can inform incentives needed for customers to find DER adoption cost-effective•Can inform the amount of program funding that can prevent or minimize cost-shift to non-participants•Can inform the amount of program funding that can promote societal benefits of DERsÊGiven these use cases for GWP , E3 conducted a benefit-cost analysis under three key perspectives:•Participants (Participant Cost Test, or "PCT")•Ratepayers (Ratepayer Impact Measure, or "RIM")•Society (Societal Cost Test, or "SCT") Applying DER cost-effectiveness challenges from other jurisdictions to GWP’s adoption targets 207
Benefit-Cost Analysis Approach
E3 conducted a benefit-cost analysis for several representative GWP customer types Results for individual representative customers were scaled up according to their share of GWP DER adoption, providing cost-effectiveness results for GWP's entire service territory The analysis covers various scenarios that reflect GWP's implementation of different programs and incentives for DER adoption The benefit-cost analysis assumes that GWP will introduce programs and/or incentives at the start of 2025 and evaluates all systems adopted from 2024 to 2030 E3 concentrated the analysis on solar and solar + storage systems, as these are the primary DER resources relevant for adoption target compliance Building Types•Single-Family•Low-Rise Multi-Family•High-Rise Multi-Family•Small C&I•Medium C&I•Large C&IIncome Classes•Low- to Moderate-Income (LMI)•Non-LMI (general market)Resiliency Values•Base resiliency value•High resiliency value 208
Benefits and Costs Components by Cost Test Perspective
ComponentParticipant Cost Test (PCT)Ratepayer Impact Measure (RIM)Societal Cost Test (SCT)Bill Savings+–Upfront Costs– –Fixed Operations and Maintenance Costs– –Federal and State Incentives+ +GWP Incentives+–Utility Avoided Costs++Resiliency Benefits+Additional Societal Benefits + N/ACostBenefitNote: Administrative costs were not included in the cost tests. When interpreting the results, please consider these additional costs from both the ratepayer and administrator perspectives to ensure that all program implementation expenses are fully accounted for.

Encouraging Customer Adoption
Realizing Value for Grid & CommunityManaging Cost-Shift & Affordability Participant Cost Test
Ratepayer Cost TestSocietal Cost Test
Section 8.2GWP Benefit-CostAnalysis Inputs & Assumptions 210
ÊUpfront costs for rooftop solar and behind-the-meter (BTM) storage systems were calculated based on the system sizes for each customer segment. These costs were used to determine the total upfront cost for system installations.ÊThe values used in this calculation were derived from RECOST, E3's internal resource pricing model, which incorporates inputs from various sources. For this study, the NREL ATB version used in RECOST was ATB 2023.

Benefit-CostAnalysis Inputs: Upfront Costs
E3 RECOST
Technology Cost Assumptions Sources: NREL, LBNL, Market DataTechnology Financing Assumptions Sources: NREL, Market Data Technology Operations Assumptions Sources: NREL, LBNL
Inputs (Database)Outputs (Calculations)
Discounted Cash Flow ModelOutputs: NPV, IRR
Levelized CostsOutputs: LFC, LCOEResults Validation
211
ÊFederal and state incentives were used to offset the upfront costs of solar and storage installations. These were applied prior to any additional GWP incentives. ÊIn scenarios with GWP direct install, incentives were assumed to still apply, leaving GWP to pay the difference between the full upfront cost and the applicable incentives.

Benefit-CostAnalysis Inputs: Federal and State Incentives Discount NameJurisdictionAmountTimelineApplicable TechnologiesSolar Investment Tax Credit (ITC)Federal30%30% expires in 2026, ITC is reduced to 22% in later years Solar and/or storageSelf-Generation Incentive Program (SGIP)California$0.45/W as a general approximation2024 and 2025 onlyStorage only, not including new buildings 212
ÊLBNL’s Interruption Cost Estimate Calculator (ICE Calculator) uses user inputs to calculate the $ per kWh of lost load•Number of Customers: GWP 2024 IRP•SAIDI and SAIFI: EIA-861Ê$ per kWh of lost load was converted to $ per total kWh annual load by multiplying by the probability of an outage in each minute•Solar and storage gets the full value since it is assumed that a BTM solarand storage system would eliminate the number of outages per year to 0•Solar-only systems get no resiliency valueÊFor this study, E3 developed sensitivities around resiliency values:•Base Resiliency: default assumption in final analysis•High Resiliency: applies a 10x multiplier to the base resiliency values Benefit-CostAnalysis Inputs: Societal Benefits - Customer Resiliency Value Source: LBNL Interruption Cost Estimate Calculator
Source: US Energy Information Administration, EIA-861 File 213
ÊThe Social Cost of Carbon (SCC) represents the net value to society of increasing or reducing carbon dioxide levels•The SCC is based on monetizing damages incurred by temperate changes, sea level rise, and CO2 concentrations as a product of increased emissionsÊSocial Cost of Carbon is calculated using the EPA’s 2022 “External Review Draft of Report on the Social Cost of Greenhouse Gases”•The 2.0% discount rate option was selected as a mid-optionÊThis value was converted to nominal dollars using historical and forward-looking inflation rates. It was then multiplied by the amount of CO2e avoided by solar and storage to calculate the final value.

Benefit-CostAnalysis Inputs: Societal Benefits - Social Costs of Carbon Table ES.1: Estimates of the Social Cost of Greenhouse Gases (SC-GHG), 2020-2080 (2020 dollars),link to source. 214
ÊImpacts of emissions on human health were calculated using the statewide Air Quality Adder (AQA). This value is recognized by the CPUC for the state societal cost test. ÊThe AQA value of $14/MWh of avoided gas generation was determined by the state-of-the-art air quality modeling done for the IDER proceeding in 2020/2021.ÊAlthough the actual impact varies by region, the CPUC uses a single statewide value. •Gas units may need to run for local reliability where impact is highest due to existing air quality concerns, weather patterns, and high population density (e.g., LA Basin). •E3 was unable to calculate a more spatially granular value within this scope of work.

Benefit-CostAnalysis Inputs: Societal Benefits - Air Quality Adder (AQA) Monetized Health Impact of Gas Generation by Location
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Calculated using internal assumptions about capacity factors of rooftop and utility-scale solar and the assumed replacement resource of rooftop solar from the avoided costs workstream Benefit-CostAnalysis Inputs: Societal Benefits - Land Use Impacts Acres of Desert Preserved
MW of Utility Scale Solar Avoided
MW of Utility-Scale Solar
$ Value of Desert Ecosystem Services
Acre of Desert Preserved
Value of Avoided Utility Scale Solar Land Use
Calculated using NREL research on single-axis large solarCalculated using research from Chen and Costanza (2024) that includes potential ecosystem benefits such as raw material provisioning, surface water value, soil fertility, and generic diversity Final calculated value is $3,768/MW-year of rooftop solar installed (in $2024) Only solar-related
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ÊThese additional inputs were run through RESTORE, E3’s internal adoption and impact analysis model, to create bill savings, avoided costs, and emissions impacts of various levels of solar and storage adoption Benefit-CostAnalysis Inputs: Additional InputsInput SourceCustomer loadsBuilding load shapes from NREL’s ResStock and ComStock modelsSolar generation profilesLocalized solar profiles from NREL’s PVWatts modelSolar and storage system sizingInternal DER potential and market segmentation analysisRetail ratesGWP’s latest residential and commercial retail rates, pulled from the GWP websiteStorage dispatch scheduleSimulated by E3’s RESTORE model in the adoption and impact analysis Section 8.3GWP Benefit-CostAnalysis Key Results
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ÊParticipant benefits include bill savings, federal and GWP incentives, and resiliency benefitsÊParticipant costs include upfront costs, maintenancecosts, and interconnection fees Participant Perspective (PCT)Net Present Value of Per Customer Costs and Benefits Single-family customer adopting solar in 2025Single-family customer adopting solar + storage in 2025 S1: Continue Current NEMS2: Targeted LMI AdoptionS3: BalancedS4: Widespread Adoption Resiliency BenefitsFederal and State IncentivesBill Savings Fixed O+MUpfront Costs S1: Continue Current NEMS2: Targeted LMI AdoptionS3: BalancedS4: Widespread Adoption ÊIn all scenarios, solar and solar + storage provide net benefits over the system's lifetimeÊDriven by high bill savings under various billing mechanisms, even under net billingÊDespite lifetime savings, high upfront costs of solar and solar + storage may still pose barriers to adoption 219
Perspective of All GWP Ratepayers (RIM)(Participants + Non-Participants) S1: Continue Current NEMS2: Targeted LMI AdoptionS3: BalancedS4: Widespread Adoption GWP IncentivesBill Savings Utility Avoided Costs
ÊLifetime costs and benefits for compensating new solar and storage adopters from 2024 to 2030ÊDetermined by the number of adopters, net metering/billing compensation level, and the level of additional utility incentives provided ÊPredictably, all scenarios have net ratepayer costs that increase GWP rates in order to accelerate DER adoption Total Glendale Ratepayer Costs and BenefitsFor Solar and Solar + Storage Systems Adopted in 2024-2030 220
ÊThe societal perspective captures benefits that accrue to society at large •Societal benefits include federal incentives, GWP avoided costs, and other societal benefits that can be monetized including reduced land use, air quality impacts, and reduced emissions•Societal costs include upfront system costs and maintenance costs Total Glendale Societal Costs and BenefitsFor Solar and Solar + Storage Systems Adopted 2024-2030ÊBenefits or costs transferred within the boundaries of Glendale are not included•For example, customer bill savings offered by GWP are not includedÊSolar and solar + storage provide net benefits to society across all scenarios•Net benefits are driven by avoided utility costs and avoided CO2 emissionsS1: Continue Current NEMS2: Targeted MF LMI AdoptionS3: BalancedS4: Widespread Adoption Societal BenefitsUtility Avoided CostsFederal and State Incentives Fixed O+MUpfront Costs Glendale Societal Perspective (SCT)
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Economic Analysis of Scenarios: Cost Test Scores
S1Continue Current NEMS2Targeted LMI/MF AdoptionS3BalancedS4Widespread Adoption Participant Cost Test

2.252.163.04

3.04 Ratepayer Impact Measure

0.280.450.390.29
Societal Cost Test

1.872.092.112.17
𝐵𝑒𝑛𝑒𝑓𝑖𝑡𝑠𝐶𝑜𝑠𝑡𝑠≥1.0
222
ÊAll scenarios have annual net ratepayer costs that increase GWP rates due to accelerating DER adoption Annual Net Ratepayer Costs
Annual Net Ratepayer Costs ($)Reference Scenario (S0)Range of Scenario Results (S1-S4)Continue Current NEM (S1) $-
$20
$40
$60
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$120
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2026
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2032
2034
2036
2038
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2052
2054
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S1 Net Ratepayer Costs
S2 Net Ratepayer Costs
S3 Net Ratepayer Costs
S4 Net Ratepayer Costs
$-
$20
$40
$60
$80
$100
$120
2024
2026
2028
2030
2032
2034
2036
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2054
Millions
S1 Net Ratepayer Costs
S2 Net Ratepayer Costs
S3 Net Ratepayer Costs
S4 Net Ratepayer Costs
S4
S2S3S1
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ÊAcross the scenarios 1 through 4, rates are anticipated to increase between 6% and 11% due to solar and storage programs on top of other anticipated sources of rate growthÊThis means that the average low- or moderate-income (LMI) customer will now be paying between $4 and $6 more per month on electricity, or $48 to $72 per year Retail Rate and Customer Bill Impacts
$-
$10
$20
$30
$40
$50
$60
$70
$80
2023 2025 2030
0%
2%
4%
6%
8%
10%
12%
2023 2025 2030
11%
6%
+$6+$4Range of Scenario Results (S1-S4)
Range of Scenario Results (S1
-S4)
Section 9Potential Program and Policy Options

Section 9.1 Overview
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ÊProgram proposals ranked by overall qualitative performanceÊReasonable DER compensation levels that mitigate cost shifts are preferred Qualitative screening analysis prioritizes program and policy options crucial for achieving City Council targets over othersPriority Level

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ÊIn addition to adoption impact modeling, which captures prioritized programs and policies, the following potential program design options are presented for prioritized programs Potential Program and Policy Options
Outreach Education & SupportStreamline & Improve Permitting ProcessNet Metering vs. Net Billing Incentive DesignFor example, upfront/base rebates, performance-based incentivesFeed-in Tariff (FiT)Solutions for Renter and LMI CustomersFor example, community solar, virtual solar 228
Equity and Justice Concerns Within DER Adoption
Distributional
Procedural
Recognition
Many customers face already high bills, some are prohibitively high. How can utilities create programs and policies that do not increase rates for non-participants? How can utilities ensure energy affordability for all customers? Not all customers receive equal treatment from the electric grid. Some customers see more frequent outages than others. How can utilities work to repair this injustice with DERs that can provide resiliency benefits? Historically, some solar and storage programs have seen a disproportionate number of incentives going to high-income customers. How can utilities ensure that incentives are aligned with those who need them most? Most solar- and storage-adopting customers across Glendale and the United States are high income homeowners. How can utilities ensure that LMI renters are also eligible for technologies that produce bill savings? Not all customers know about available programs. How can utilities spread knowledge about programs to those who need them most? Involving all types of customers in decision-making and planning yields more equitable policies. How can utilities highlight marginalized voices in the decision-making process? 229
ÊUnder traditional NEM programs, a landlord would pay upfront solar and storage costs, but tenants would see the bill-savings benefits. This “split incentive” problem has led to much lower solar and storage adoption rates for renters than homeowners. Solutions to the “split incentive” problem focus on allowing customers to gradually pay back the upfront costs of solar or storage.

Providing Access for Renter and LMI Customers
Solar or Storage LeaseCustomers pay a monthly fee for solar panels or storage to be installed on their roof.

Community SolarCustomers subscribe to a share of a larger solar installation and pay a monthly fee to receive bill savings.

Virtual SolarCustomers in multi-unit buildings can subscribe to a shared solar installation.

On-Bill FinancingUtility pays the upfront costs, which are then recovered on customer bills.

Green RatesCustomers pay a higher electricity rate to opt for 100% clean energy.

ÊSome, but not all, of these programs also allow customers without roof space (i.e., apartments and condos) to adopt solar and storage. 230
For solar, multiple types of programs could exist in Glendale Net Energy Metering (NEM)Individual customers install solar or storage in their own buildings.

Virtual SolarCustomers in multi-unit buildings share a single solar and storage installation across all units.

Community Solar (CS)Customers subscribe to a share of an off-site larger solar installation.

Section 9.2Program Deep Dive: Incentive Design
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Incentive design can be diverse and can be used to encourage beneficial behaviors High incentives in the near term and lower incentives in later years could encourage early adoption.

Apart from performance-based incentives, upfront incentives can also be offered in exchange for optimal storage dispatch.

Additional incentives for bundling solar and storage installations could be used to increase storage adoption.

Explore including tax abatements (e.g., property tax) such as NYC's property tax abatement for solar and storage.

Explore the possibility of direct install programs for multifamily, low- and moderate-income, or disadvantaged communities.

Utilize state and federal level support to help residents secure the California Self-Generation Incentive Program (SGIP) incentives through SoCalGas, considering that most Glendale residents might use their gas service.

Consider alternative funding mechanisms or sources that mitigate the burden to low-income and disadvantaged communities (e.g. , property tax or Income Graduated Fixed Charges). 233
Encouraging customers to dispatch storage for grid needs increases community benefits Flat Rate
Flat Rate
Solar Generation

ILLUSTRATIVE
No Storage Charge/Discharge in Normal Days
ÊCustomer-owned storage used for back-up power or bill reductions provides little or no benefit for the Glendale community Solar
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ÊPrograms that provide price signals to customer-owned storage for a limited number of hours in the year can increase community benefits substantially Encouraging customers to dispatch storage for grid needs increases community benefits Utility Signal
Dispatch Signal
Solar Generation
Storage Charge
Storage Discharge

ILLUSTRATIVE
Solar
235
Additional incentives lessen costs for DER adoption•Additional incentives from GWP would allow customers to install solar and storage at lower costs, mitigating the upfront cost barrier or improving lifetime investment return.•These incentives could be partial upfront/base rebates, full direct install programs, or performance-based incentives that encourage customers to dispatch battery storage for grid needs and increase community benefits.•These incentives could be offered to all residents or targeted at specific types of customers, such as low-income multi-family apartment buildings.•The City of Glendale offered incentives for solar in the past, but they have been phased out.

Benefits: •Reducing the cost to install solar and storage increases access for low- and moderate- income customers.•Reductions in upfront costs and improved lifetime investment return increase adoption across all customers.

Possible Concerns:
•Upfront incentives alone cannot solve physical and technical constraints faced by many renters and condo owners, and performance-based incentives might require additional tele-communication technology support.•High incentives increase the revenue that GWP recovers, which in turn increases rates.•Restarting the incentive program may pose an issue for customers who did not receive the incentive between the end of the old program and the beginning of the new program.

Section 9.3Program Deep Dive: Rooftop Solar Compensation 237
Glendale’s Current Approach to Solar CompensationGlendale uses Net Energy Metering (NEM) to compensate customers for their rooftop solar. This tariff is called the “Customer Owned Generation” tariff.•Under NEM, solar exports and self-consumption are compensated at the exact value of solar imports.•This type of policy, like the CPUC’s NEM 1.0, has high compensation values and creates a strong incentive for customers to adopt solar.•NEM leads to a significant cost shift since solar exports and self-consumption are compensated above the avoided cost of the utility not having to procure that energy.The “Customer Owned Generation” tariff is capped at 5% of GWP’s total peak demand.•The tariff is first-come, first-serve for customers.GWP caps large solar systems (<10kW) at 110% of annual load or 1 MW-AC.

Very few customers in Glendale (<2%) are subscribed to time-of-use (TOU) rates.•GWP has faced technical difficulties installing electric meters compatible with TOU rates.<2%110%5% NEM 1.0
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Rooftop solar can be compensated by the utility in many different ways TariffSelf-ConsumptionExports Bill SavingsCost ShiftNet Energy Metering (NEM)All generation (both self-consumption and exports) credited at the customer’s import rate ++++++Net Billing (NEB)Self-consumption credited at the import rateExports credited at a reduced export rate++++Buy-All, Sell-All(BA, SA)All generation (both self-consumption and exports) credited at a reduced export rate ++ Note: “Net Metering / NEM” is often used erroneously/colloquially to describe all tariffs for crediting exports from customer-generators Self-consumption3,000 kWh/yrImports4,500 kWh/yr
Exports4,500 kWh/yr
7,500kWh total consumption7,500kWh total generation
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Options for Program Improvements: Rooftop Solar Compensation Compensation RatesShift solar and storage compensation to a net billing tariff structure.Align export compensation with GWP avoided costs.Require TOU rates for solar and storage program enrollment.

Program Sizing ConstraintsExpand total program size by allowing more customers to be subscribed to the customer generation tariff.Relax constraints on system sizing.

Section 9.4Program Deep Dive: Virtual Solar
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Virtual solar allows building owners to share solar and storage credits with multiple units•Virtual solar creates an economic, but not necessarily physical, connection between multiple units within a single building. •This type of program is modeled after the California Public Utility Commission's VNEM program but could be implemented in many different ways.

Benefits: •Virtual solar allows renters and apartment owners who cannot install solar or storage on shared roofs to access the benefits of solar and storage.•Upfront customer costs may be lower than single-unit solar installations due to economies of scale.

Possible Concerns: •Property owners may require high compensation or incentives to consider installing virtual solar. •The utility's billing could be complicated.

Section 9.5Program Deep Dive: Community Solar
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ÊEnabling customer choice and providing a “green” or “clean” option to ultimately reduce low-to-moderate income (LMI) customer energy burdens is the key driving force behind state- and federal-level policy action à 10-30% bill reductions are the target•Federal policy has taken the form of large incentives for community solar installations via the 2022 Inflation Reduction Act–LMI Bonus Credits (10% ITC bonus for siting in LMI communities and an additional 20% ITC bonus for directly serving LMI customers) for up to 1.8 GW-DC of installations in 2023 and 2024•Results in up to 50% ITC benefits–Interconnection costs included in ITC for under 5 MW projects–$7B in state funds to create/expand distributed solar programs•State policy actions have been broader and more diverse in terms of scale/scope ranging from small pilots to large multi-GW/$billion programs–Explicit trade-offs and competing interests between providing distributed solar access to underserved communities like LMI and/or renters at least cost vs. creating a robust “market” for non-utility electricity providers like 3rd party community solar developers/owners Avoiding high rates/bills, especially for low- to-moderate income customers, is a driving force for policy action 244
Design choices vary by state but follow common archetypes Asset Ownership
Customer Compensation
Enrollment
Program Size
Project Eligibility
Nationally, capacity roughly split between utility and third-party ownership Typically mirrors retail rate structure and compensation for exported solar, which vary from state to state Generally, all customers are eligible, with minimum/maximum subscription levels placed on C&I and residential customers New programs often start with targets around 100-200 MW; mature programs are reaching scales in excess of 1,000 MW Most programs have a cap on project size between 1-5 MW and allow solar only; hybrid projects still uncommon unless required 245
ÊTwo prevailing models for ownership of community solar facilities:•Third-party ownership:a third party (developer, retail electric provider)builds, owns, and operates the array and enrolls/manages customers•Utility ownership: The utilityowns the solar arrayand sells portions of the project to customers, who receive monthly bill creditsÊUtilities often purchase projects that have been developed by third parties via build-own-transfer agreements•In some cases, utilities market to customers while third parties retain ownershipÊPreferred ownership structures vary from state to state; in some cases, states have used hybrid models for ownership Common Community Solar Ownership and CompensationÊAsset owner is typically responsible for enrollment and contracting with customers •Customers pay either subscription or energy charges and receive credits towards their electricity bills•Different mechanisms are used for customer bill offsetsÊCredit value calculations vary by state:•Value of solar: credits based on administratively determined “value of solar” calculations•Full retail rate: customers’ bill credits offset kWh consumed on a 1:1 basis•Discounted retail rate: customers’ bill credits offset kWh consumed on a discounted basis•Other: negotiated and/or competitively determined rate•Additional incentive value “adders” possibleÊREC ownership varies based on program design 246
Program EnrollmentsPrograms typically require a share to be contracted with residential/low to moderate-income (LMI) customersPrograms may have limits on shares allocated to individual C&I customersDevelopers often use subscription management companies to market and manage customer operations Program SizeProgram sizes range from 50 MW to GW+ in more mature markets Programs often begin around 100-200 MW but very much depends on the potential size of the marketVoluntary markets (those without policy directives) do not have program limitations Project EligibilityProject sizes in programs across the U.S. are typically five MW or lessSome states have minimum project sizes that are 1-2 MWVoluntary markets do not have size limitations Other elements of community solar program design
Section 9.6Program Deep Dive: Feed-in-Tariff
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Feed-in-tariffs (FiT) provide economic certainty to developers interested in interconnecting solar or storage in Glendale•A feed-in tariff (FiT) is a guaranteed price for renewable power producers that ensures their long-term compensation. •Unlike NEM, which is focused on sizing solar to serve onsite load, FiTs are designed to allow participants to maximize their site’s solar potential, unlocking properties within city limits that are not eligible for NEM, such as carports and parking canopies. •Examples: LADWP has a FiT program that allows eligible sites to sell energy directly to the utility, rather than using it to offset load. LADWP’s “Carport and Canopy” incentive is a one-time rebate for large parking lot owners.

Benefits: •FiTs have significantly increased investment in renewables in other jurisdictions.•Most developers are unlikely to build resources without a long-term contract in place to guarantee payment for their energy.•FiTs encourage solar and storage development on underutilized surfaces, such as brownfields, landfills, and parking canopies.Possible Concerns: •By entering a contract, Glendale cannot change compensation to align with the market in future years.

249
Options for Program Improvements: Feed-in-Tariff
Program Sizing ConstraintsExpand total program size beyond 4.2 MW. Remove the 1.4 MW constraint on system sizing.

Section 9.7Robust Customer Outreach, Education, and Resource Support 251
Conduct comprehensive outreach and educational campaigns to enhance awareness and empower residents to make informed decisions with an understanding of the underlying economics Enhance outreach and educational campaigns to improve customer awareness and empower residents Additional outreach on federal and state support (IRA, SGIP , etc.) Proposed adoption programs that use mechanisms that customers intuitively understand Comprehensive outreach and knowledge campaigns from GWP to inform and educate residents: 1) Enhance awareness, 2) Understand costs and benefits, 3) Grasp the economics involved, and 4) Enable informed decision-making

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Examples of improving support and guidance via web resourcesHow to Work with DevelopersSolar and DER BasicsCertified/Approved ContractorsUseful Data EV Electricians List: Provides lists of certified electricians for EV customers.

NYSERDA Approved Contractors
ABP Approved VendorsCalifornia DGStats Database: Includes data for solar NEM/NBT and energy storage interconnection applications within PG&E, SCE, and SDG&E territories, providing valuable starting information for Glendale customers. Check this SCE example.

Battery Storage Guidance: comprehensive webpages providing detailed guidance on battery storage and solar solutions Going Solar Webpage: offers guidance on installing solar, finding contractors, and lists federal and state incentive support

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ÊInformation on solar and battery storage contractors is now available on the GWP website GWP already took actions to improve their resource supportwww.glendaleca.gov/SolarContractors

Section 9.8Improved Permitting, Interconnection, and Approval Process 255
ÊA significant volume of permits must be processed in the near term when customers begin installing DERs; this volume has the potential to overwhelm the existing City of Glendale processes.ÊGWP needs a faster, easier, and more scalable permitting, interconnection, and approval process to reduce barriers and constraints to DER adoption.

Automate and simplify the process of installing solar and battery storage Automated review and approval of customer projects can reduce costs and speed up timelines. NREL’s SolarAPP+ is a free software platform offering process automation. GWP has adopted SolarAPP+.Simplify inspection processes with straightforward checklists for residential solar and energy storage permits to avoid delays and extra costs. Virtual inspections can further streamline utility review, permitting, inspection, and interconnection.

Reduce permitting and interconnection fees and provide waivers for low-income customers.

Allow solar systems to be sized for future load growth from electric vehicles and appliances.

Section 9.9On-Bill Financing & Repayment
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ÊOn-bill financing (OBF) and repayment (OBR) are methods where a utility or private lender provides funds for energy efficiency, renewable energy, or other generation projects. Repayment is made through regular charges on the customer's utility bill.•OBF/OBR offers advantages such as low or zero interest rates, straightforward contracts, and easy repayment. •However, these options are only available in areas where utilities offer on-bill programs.

On-Bill Financing/On-Bill Repayment (OBF/OBR)
PG&E requested authorization for an OBF/OBR Pilot starting in March 2021 to support K-12 schools installing clean power projects. The pilot will finance the SGIP-eligible storage components to improve resiliency during power outages: link PG&E Supports Restaurant Business Customers via OBF: PG&E offers 0% interest loans for replacing old and worn-out equipment with more energy-efficient models to qualified non-residential PG&E customers. •PG&E OBF Handbook•Assistance summary Better Buildings, an initiative of the U.S. Department of Energy (DOE), provides a comprehensive guide on OBF/OBR with how it works, procs and cons, state of the market, case studies, and additional resources: link Typical On-Bill Financing or Repayment Structure
Note: Materials in this slide are adapted and customized from Better Buildings Solution Center.

Landlord/Tenants
258
ÊOBF/OBR typically targets homeowners, but a well-designed program can also address split incentive issues between landlords and tenants with necessary modifications and customizations.ÊTo increase access for renters, project costs and incentives in the form of electric bill savings could accrue to both landlords and tenants to provide proper incentive signals. ÊHere is one conceptual program framework:

Expanding and customizing OBF/OBR to address split incentive issues for landlords and tenants Example OBF/OBR Scheme for Rental Unit(s)
•Adopted and customized from Bird, S., & Hernández, D. (2012). Policy options for the split incentive: Increasing energy efficiency for low-income renters. Energy Policy, 48, 506-514. https://doi.org/10.1016/j.enpol.2012.05.053 As part of the agreement, tenants are responsible for covering the loan payments and can benefit from savings on their energy bills. A net monthly saving for tenants can reduce tenants' energy costs while supporting their transition to cleaner energy sources.Provide small financial incentives to landlords to offset the costs associated with managing and overseeing the upgrade process, thereby encouraging their active participation.•For example, a small portion of the tenant's monthly bill savings can be shared with landlords in the form of a small monthly payment on the tenant’s utility bill for the first five years, which would help reinforce and make tangible the benefits of participating in the program for landlords. 259
More Information on Basic and Contract Structure AttributesÊProject Type: which project types can be financed using this option?ÊApplicable Sectors: which customer sector does it commonly serve?ÊGeographic Scope: is it available throughout the U.S. or only in limited areas with supporting policies?ÊBuilding Ownership: does it work well for leased, owned, or both?ÊTypical Project Size: what range of project sizes does it commonly serve?ÊContract Complexity: how complex is it from the customer's perspective?ÊParties Involved: what type of organizations are typically involved in executing this option?ÊPayment Type: are customer payments fixed over time or typically variable? Overview of Typical OBF/OBR Structure
Note: Materials in this slide are adapted and customized from “On-Bill At-A-Glance” in Better Buildings Solution Center. 260
Overview of Policy Responses to the Split Incentive Problem •Adopted and reformatted from Bird, S., & Hernández, D. (2012). Policy options for the split incentive: Increasing energy efficiency for low-income renters. Energy Policy, 48, 506-514. https://doi.org/10.1016/j.enpol.2012.05.053 ContractsRegulationAll-in Services
Section 10Discussion

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ÊScenarios are shaped by stakeholder input, policy directives, and GWP’s goals. Each scenario’s proposed program portfolio was evaluated based on how effectively it addresses these values from various perspectives.ÊContinuing the current NEM structure may lead to higher costs. However, a strategically planned program and incentive portfolio could drive greater solar and storage adoption, improve distributional equity, and reduce ratepayers' costs.

Metrics of Success by Adoption Scenario
GWP ImpactsDistributional Equity ImpactsSolar Adopter ImpactsNet Economic Societal BenefitMinimize Cost ShiftReduction of GHG ImpactsEase of ImplementationLMI Customer AdoptionIncreased AdoptionAdopter Financial ValueRenter Adoption S1Continue Current NEMS2Targeted LMI MF Adoption
S3Balanced
S4Widespread Adoption
Mid
HighHighHighHigh
Very HighVery High
Very HighLowLowHighHigh
HighHighVery Low
HighHigh
HighHighLowHighHighMidVery Low
Low
Mid
Very Low
Mid
HighHigh
Very High
Societal and Ratepayer Impacts
Low
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Clarifications on how to correctly interpret the City Council’s adoption targets are necessaryAt least 10% of GWP customers adopt solar and energy storage systems by 202710% adoption target for solar + storage systems vs. 10% for either solar or solar + storage systems? Develop additional demand management measures, with a minimum total peak dispatchable and peak-load-reducing capacity of 100 MW Which systems qualify?
Standalone SolarSolar + StorageStandalone Storage
100 MW nameplate or effective capacity?
Nameplate CapacityEffective CapacityVS.
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1.Rooftop solar owned, financed, or leased by single-family customers (one system for one electric customer)2.Rooftop solar owned, financed, or leased by multi-family property owners/managers under virtual net metering programs and shared among tenants and unit owners (one system for multiple electric customers)3.Subscribers of off-site solar solutions like community solar, solar share, and green rate options (one project for numerous electric customers)All options must be carefully evaluated for cost-effectiveness against other solar solutions, particularly lower-cost utility-scale city-owned options.

Can GWP reach 10% customer solar adoption by 2027?Including solar-only and solar + storage systems ÊThe goal is not realistically achievable by 2027ÊThe projected net cost to GWP ratepayers is $23-$45 million from 2024 to 2027. This estimate accounts for bill savings, utility incentives, and avoided costs.ÊElectric rates could increase in various adoption scenarios, in addition to other sources of anticipated rate growth•By 2025: 3%-6%•By 2027 (interpolated): 4%-8%•By 2030: 6%-11%ÊPrerequisites needed:1.Robust community outreach and support2.Improved permitting processes3.Available solutions to address split incentives Achieving 10% Adoption by 2027
•Achieving 10% adoption by 2030 is theoretically feasible, but with a significant investment and retail rate impact on GWP ratepayers.•The adoption level results will be further limited by implementation barriers, customer adoption behavior, and other financial and non-economic barriers that customers face. As a result, utility program costs are expected to be higher to account for those factors.

Eligible Solar System Configurations
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1.Customer storage owned, financed, or leased by single-family and multi-family property owners/managers and commercial and industrial customers2.Subscribers of off-site solar and storage solutions like community solar/storage, solar/storage share, and green rate options3.To fill in the gap, options like distribution grid storage, customer storage at city-controlled sites, or GWP-installed storage hosted on customer sites could be explored All options must be carefully evaluated for cost-effectiveness against other storage solutions, particularly lower-cost utility-scale city-owned options.

Can GWP reach 10% customer storage adoption by 2027?Including solar + storage systems ÊThe goal is not theoretically feasible considering upfront costs and storage attachment rates in California.ÊThe impact of incentives on accelerating storage adoption is limited since battery storage has historically been driven by resiliency considerations rather than economic factors. ÊSubstantial upfront costs and diminished benefits, including low TOU participation and symmetric NEM rate schedules, hinder adoption. ÊOnly 7% of customer solar systems in Glendale have battery storage. Across California, only 6%- 19% of customer solar systems have storage, varying by income level. Achieving 100% attachment rates requires significant utility interventions.

Achieving 10% Adoption by 2027
•Achieving 10% customer storage adoption by 2027 is very ambitious and not theoretically feasible considering the realistic level of storage attachment rates in California.•Additional study is needed to determine a more realistic and achievable target.

Eligible Storage System Configurations

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Peak load reductions decline with increasing solar and storage adoption Solar Impact on Net Load(MW)
Hour of Day
Storage Impact on Net Load(MW)
Hour of Day

ILLUSTRATIVEILLUSTRATIVE
Incremental Solar Additions (10 GW in total)
Incremental Storage Additions (5 GW in total)
•Net peak load shifts to after sunset•Effective capacity per MW of storage declines 267
Can GWP reach 100 MW dispatchable and peak load reduction capacity by 2027? ÊCustomer-owned solar and storage would provide reliable peak load reductions of 10 MW or less by 2027ÊIncluding other DERs such as demand response, managed electric vehicle charging, and energy efficiency could theoretically provide peak load reductions of 20-44 MW by 2027ÊEffective Capacity: achieving 100 MW of reliable peak load reduction could require 200-300 MW customer solar, 40-60 MW customer storage, and other DERsÊNameplate Capacity: theoretically feasible with significant utility investment and a later target year Achieving 100 MW additional effective capacity, considering DER’s ability to reduce GWP system peak demand, will require 200-300 MW DER nameplate capacity coming online by 2027. Additional study is needed to determine a more realistic and achievable target.

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Can GWP reach 100 MW dispatchable and peak load reduction capacity by 2027?ÊCustomer-owned solar and storage would provide reliable peak load reductions of 10 MW or less by 2027ÊIncluding other DERs such as demand response, managed electric vehicle charging, and energy efficiency could theoretically provide peak load reductions of 20-44 MW by 2027ÊEffective Capacity: requires approximately 200-300 MW customer solar, 40-60 MW customer battery storage, and other DERs by 2027ÊNameplate Capacity: theoretically feasible with significant utility investment, suggest considering a MW nameplate capacity goal and a later target year Achieving 100 MW Additional DER by 2027:
•Achieving 100 MW additional effective capacity, considering DER’s ability to reduce GWP system peak demand, will require 200-300 MW DER nameplate capacity coming online by 2027.•A more realistic target is achieving 100 MW additional DER nameplate capacity with a later target year.

DER Contributions by 2027
DERNameplate Capacity (MW)Approx. ELCC (%)Effective Capacity (MW)Customer Solar39-700-70-5Customer Storage3-1035-451-5LDEV Managed Charging50-5528-3814-21Energy Efficiency0-5100*0-5Residential and C&I DR8-1268-785-9Total MW100-15220-44 * EE capacity here represents ‘peak saving’ forecast from GWP IRP , E3 assumes peak saving already accounts for capacity contributions (i.e. after ELCC adjustment) 269
Key Takeaways: Cost and Benefit AnalysisParticipant Perspective•In all scenarios, solar and solar + storage provide net benefits over the system's lifetime•Net benefits are driven by high bill savings under various billing mechanisms, even under net billing•Despite lifetime savings, high upfront costs of solar and solar + storage may still pose barriers to adoption SocietalPerspective•Solar and solar + storage provide net benefits to society across all scenarios Ratepayer Perspective•All adoption scenarios have net ratepayer costs, meaning compensation provided to solar and solar + storage customers higher than the cost savings for GWP•A strategically planned program and incentive portfolio can achieve higher solar and storage adoption with lower impacts on GWP ratepayers

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Findings: Achieving the adoption goals by 2027 is not feasibleAchieving a goal of 10% customer solar adoption by 2027 is not feasible. The goal is theoretically feasible by 2030 with a significant increase in utility costs and effort, but real-world barriers remain.Achieving a goal of 10% customer storage adoption in the near future is not feasible. Achieving a goal of 100 MW of reliable peak load reduction with DERs is not feasible.

Industry studies suggest that achievable potential is 20%-40% of the technical potential.

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Findings: Adoption of customer-owned solar and storage increases GWP rates The scenarios achieving 10% solar adoption would result in a projected net cost of $23-$45 million to GWP ratepayers from 2024 to 2027. §Implement a Net Billing Tariff to reduce the cost shift.§Develop and implement non-bypassable charges and fixed customer charges to reduce the cost shift.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement a Net Billing Tariff.

The resulting rate increase would be 6-11% by 2030, with a low- and moderate-income (LMI) customer monthly bill increase of $4-$6.

Recommendations
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Findings: Current customer-owned solar and storage adoption is predominately by single-family homeowners above the median incomeCustomer solar adoption in Glendale to date is above 10% for single-family homes and below 1% for renters and LMI customers.84% of customer solar adoption is in households above the median income. 88% of customer solar adoption is by property owners.
90% of customer solar adoption is in single-family homes. §Allow lower cost community solar and storage to count towards achieving the adoption goal.§Evaluate virtual solar programs that renters and LMI customers can subscribe to.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement virtual solar programs.

Recommendations
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Findings: Customer-owned solar and storage provides limited reliable peak capacity reduction §Implement TOU rates that encourage customer storage adoption and dispatch for peak capacity reductions.§Study and expand demand response, electric vehicle, energy efficiency, utility dispatchable DER, and other programs for peak load reductions.§Evaluate the cost and feasibility of changes to GWP’s billing and metering systems needed to implement TOU rates and utility dispatchable DER.

The effective capacity of customer-owned solar is less than 10% of the installed capacity.

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Findings: Additional costs not included in this study will be required §Evaluate Glendale-specific program elements that will be the most effective for increasing DER adoption by renter, LMI, and DAC customers.§Evaluate the cost and feasibility of necessary changes to GWP’s billing and metering systems.§Consider the cost of additional program overhead and customer outreach.

Recommendations
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Findings: Adoption Strategies
Utility interventions are necessary (utility support + utility incentives).•Utility interventions are necessary to accelerate customer adoption.•Enhancing customer outreach, support, and simplifying the permitting process alone can boost solar adoption to reach 10% adoption by 2030 without further utility interventions but have a limited impact on promoting battery storage adoption.•Providing additional utility incentives and access for renter and LMI customers are also needed to accelerate customer adoption, along with improving utility support.

Building code-compliant solar and storage adoption from new construction contributes significantly to achieving the adoption target.•By the end of 2027, the adoption of building code-compliant customer solar and storage systems could account for 15% to 20% of the total customer adoption required to meet the 2027 target, assuming a 90% compliance rate (due to exceptions and waivers).

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Conduct comprehensive outreach and educational campaigns to enhance awareness and empower residents to make informed decisions with an understanding of the underlying economics Enhance outreach and educational campaigns to improve customer awareness and empower residents Additional outreach on federal and state support (IRA, SGIP , etc.) Proposed adoption programs that use mechanisms that customers intuitively understand Comprehensive outreach and knowledge campaigns from GWP to inform and educate residents: 1) Enhance awareness, 2) Understand costs and benefits, 3) Grasp the economics involved, and 4) Enable informed decision-making

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ÊA significant volume of permits must be processed in the near term when customers begin installing DERs; this volume has the potential to overwhelm the existing City of Glendale processes.ÊGWP needs a faster, easier, and more scalable permitting, interconnection, and approval process to reduce barriers and constraints to DER adoption.

Reduce permitting and interconnection fees and provide waivers for low-income customers.

Allow solar systems to be sized for future load growth from electric vehicles and appliances.

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Findings: Program OptionsThe balance between cost, affordability, and adoption impact must be carefully considered when selecting program portfolios to ensure that GWP equitably meets its adoption targets.•Continuing current NEM will have higher costs - continuation of the current NEM policy primarily benefits single-family homeowners, with a projected rate increase of 6% by 2030.A strategically planned program and incentive portfolio can achieve higher solar and storage adoption with lower impacts on GWP ratepayers.NEM Rate Design Evolution •Lower costs can be attained through the adoption of the Net Energy Billing (NEB) system with lower export compensation that better aligns with system costs (along with adders to protect customer investment payback period), which is more equitable than Glendale's current NEM program.•Customers will receive lower bill savings, which could slow adoption from single-family households. However:•Expanding program eligibility to the multi-family sector will create a new source of customer adoption•Cost shifts are reduced•Additional incentive programs can be implemented to increase the adoption rate Additional Incentive Programs•Improve customer economics: Adoption from multifamily, rental, and LMI/DAC households and customers in pollution-burdened areas can be accelerated by additional utility incentives, such as:•Upfront incentives and performance-based incentives that secure customer payback for 5-7 years•Direct install programs targeted at these customer segments•Prioritize breadth over depth: Direct install in targeted customer sectors is less cost-effective than incentive programs that have lower incentive levels but with broader customer eligibility•Strength in numbers!

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Strategically planned programs and incentives could boost solar and storage adoption while reducing impacts on GWP ratepayers Solar LeaseCustomers pay a monthly fee for installing solar panels on their roofs.

Community SolarCustomers subscribe to a share of a larger solar installation and pay a monthly fee to receive bill savings.

Virtual SolarCustomers in multi-unit buildings can subscribe to a shared solar installation.

On-Bill FinancingThe utility pays the upfront costs, which are then recovered on customer bills.

Green RatesCustomers pay a higher electricity rate to opt for 100% clean energy.

Provide Access for Renter and LMI CustomersProvide off-site solar, virtual solar, and financing programs to address split incentives between owners and tenants:Provide More Utility SupportEnhance customer outreach and support, and simplify the permitting process Consider Alternatives to NEMAdopting a Net Billing Tariff can reduce cost shifts to other GWP ratepayers and be more equitable than Glendale’s current NEM program Provide Additional IncentivesTo accelerate adoption among multifamily, renter, and LMI/DAC/pollution-burdened customers, consider the following:•Upfront or performance-based incentives to improve payback to 5-7 years•Offer $1.0-1.5/W incentives for both solar and storage•Broader customer eligibility with lower incentives are typically most cost effective than targeted customer groups with higher incentives •Lower export compensation to align with system avoided costs•Consider avoided cost adders to improve the customer’s payback period 280
ÊWhile E3's analysis outlines several promising options to accelerate DER adoption, it is important to recognize the practical limitations GWP faces.ÊAchieving the ideal program outcomes will require addressing these implementation challenges and balancing what should be done with what can realistically be achieved, considering GWP’s existing infrastructure and resources.

Practical challenges in implementing recommended program options must be considered Renter and LMI CustomersVirtual Solar Option: providing virtual solar options for renter and LMI customers is essential for addressing financing and split incentive challenges, but it will require a major billing system upgrade, which will include budgeting for development costs, determining staff requirements, and setting realistic timelines for deployment.

Provide More Utility SupportEnhanced Community Outreach: Managing a more robust community outreach program will require significant internal resources, including staff and potentially new tools or partnerships to engage a broader segment of GWP customers.Permitting Improvements: Improving the permitting process will require coordination across departments, external stakeholders, and potentially new tools for the inspection process, adding complexity to timelines.

NEM CompensationCustomer Billing System Limitations: GWP’s current billing system currently cannot deploy TOU rates to all customers. Upgrading the system to handle TOU rates will take considerable time and investment, delaying full implementation.

Customer Support Programs: Expanding GWP’s capacity to provide direct customer support, such as education on DER options and financial assistance, will require substantial operational changes, including new staffing, training, and communication workflows.

NBT Adoption: Adopting a NBT requires City Council approval. This includes filing a regulatory-grade avoided cost analysis to determine export rate compensation. The filing process could be lengthy and complex, making it unlikely to be available by early 2025.

Section 11Appendix

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ÊNREL REPLICA dataset provides estimates of residential rooftop solar technical potential at the U.S. census tract level with emphasis on low-to-moderate income (LMI) populations•Derived from rooftop suitability modeling for 128 U.S. cities and metropolitan areas using LiDAR data from the Department of Homeland Security, representing approximately 40% of the population•A statistical model trained on areas with data coverage was used to estimate technical potential for the rest of the nationÊIncludes estimates of the number of households, number of suitable buildings, number and area of developable planes (m2), total capacity potential (MW), and total annual generation potential (MWh) for each of 20 demographic combinations:•Area Median Income (0-30% AMI, 30-50% AMI, 50-80% AMI, 80-120% AMI, >120% AMI)•Housing Type (multi-family vs. single-family)•Tenure (renter vs. owner)ÊDemographic data from 2011-2015 American Community Survey (ACS) 5-Year Estimates combined with LiDAR data to estimate solar technical potential at tract level by income, building type, and tenure NREL Rooftop Energy Potential of Low-Income Communities in America (REPLICA) LiDAR Data Coverage
Residential Rooftop Solar Technical Potential (GWh)
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SB535 Disadvantaged Communities (DACs)Share of combined multi-family, renter, and LMI customers Rooftop Solar Technical Potential (MW per km2 Census Tract Area)% Combined MF , Renter, and LMI Customers(by Census Tract) NREL REPLICA Residential Rooftop Solar Technical Potential in Glendale

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Load flexibility can come in many forms
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V1G V2G Solar PVBattery Storage
Space CoolingSpace HeatingWater Heating Pool Pump
Greatly reduces peak-coincident chargingShaves peak
Exports to the grid
Optimal shift of solar net load(on left)
Peak cooling load shifted to low-cost solar hoursSmooths out heating loadSpreads water heating across lower-cost hours Aligns pump load with solar generation Original LoadLoad after FlexibilityGreatly reduces peak-coincident charging Serves building/grid load in high-cost hours
•V1G: One-directional smart charging that allows vehicles to charge from the grid at different times and speeds.•V2G: Bi-directional capability that enables vehicles to both charge from and discharge to the grid. 285
DERs may provide many benefits, but not all provide measurable benefits to ratepayers ÊData accessÊEquipment ratings and performanceÊEnvironmental justice benefitsÊLocal workforce benefits ÊEconomic developmentÊTechnology developmentÊImproved public awareness ÊProcurement cost reductionÊTransmissions capacity savingsÊDistribution capacity savingsÊEmissions savingsÊOperations and maintenance savings ÊFuel cost savingsÊReserve capacity costs reductionÊLine loss reductionÊReduced methane leakageÊEnvironmental justice benefitsÊVoltage regulation/optimizationÊFinancial risk reductionÊReliabilityÊResilience ÊEmissions savingsÊLand use impactsÊReduced water consumptionÊBringing in federal incentive dollarsÊReduced criteria pollutants Qualitative Benefits
Monetized Benefits(Ratepayer POV)= Avoided Costs
Quantifiable Benefits

Glendale City CouncilNovember 19, 2024

Glendale City Council
November 19, 2024