Solar on Superstores
How the Roofs of Big Box Stores Can
Help America Shift to Clean Energy
Solar on Superstores
How the Roofs of Big Box Stores Can
Help America Shift to Clean Energy
Written by:
Gideon Weissman and Judee Burr
Frontier Group
Bret Fanshaw and Rob Sargent
Environment America Research & Policy Center
Spring 2016
Acknowledgments
Environment America Research & Policy Center sincerely thanks Gary Cook of Greenpeace, Bradley Dakake of Sunpower, and Benjamin Inskeep of NC Clean Energy Technology Center for their review of drafts of this docu- ment, as well as their insights and suggestions. Thanks also to Tony Dutzik and Kim Norman of Frontier Group, as well as Jeff Inglis and Lindsey Hallock, formerly of Frontier Group, and Vincent Armentano, former Frontier Group intern, for their contributions and editorial support. Additionally, Frontier Group thanks ESRI for granting the use of their ArcGIS mapping software.
Environment America Research & Policy Center thanks the Tilia Fund, the Barr Foundation, the John Merck Fund, Fred & Alice Stanback, the Scherman Foundation, the Arntz Family Foundation, Kendeda Foundation, Gertrude and William C. Wardlaw and the Fund for New Jersey for making this report possible.
The authors bear responsibility for any factual errors. The recommendations are those of Environment America Research & Policy Center. The views expressed in this report are those of the authors and do not necessarily reflect the views of our funders or those who provided review. © 2016 Environment America Research & Policy Center
Environment America Research & Policy Center is a 501(c)(3) organization. We are dedicated to protecting America’s air, water and open spaces. We investigate problems, craft solu- tions, educate the public and decision makers, and help Americans make their voices heard in local, state and national debates over the quality of our environment and our lives. For more information about Environment America Research & Policy Center or for additional copies of this report, please visit www.environmentamericacenter.org.
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Cover photo: Courtesy of IKEA
Contents
Executive Summary.................................................................................. 1 Introduction........................................................................................... 4 Large Commercial Buildings Can Be a Significant Source of Solar Energy . . . . . . . . . . . . . . . . . . . . . . .5 The United States Has Vast Solar Energy Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Every State Can Meet Its Electricity Needs with Solar Energy............................................ 6 The United States Has 100 Times More Solar Photovoltaic Capacity Than It Had in 2005.................. 6 Solar Energy Costs Continue to Fall .................................................................... 6 Commercial Rooftops Can Host a Large Amount of Solar Energy .......................................... 7 Solar Potential on America’s Big Box Stores and Shopping Centers...................................... 8 The Benefits of Scaling Up Commercial Rooftop Solar Power.............................. 12 Big Box Solar Power Brings Widespread Community Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Reducing Global Warming Pollution.................................................................. 12 Creating a Resilient Electricity System................................................................. 14 Cutting Consumer Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Reducing Air Pollution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Creating Jobs........................................................................................ 15 Big Box Stores Directly Benefit from Hosting Solar Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 New Financing Tools Can Help Businesses Overcome Hurdles to Solar Adoption..... 18 Policy Recommendations.......................................................................... 19 Appendix A: Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Solar Capacity and Generation on Commercial Buildings................................................. 21 Electricity Consumption of Big Box Stores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Global Warming Emissions Reductions.................................................................. 23 Appendix B: Tables.................................................................................. 25 Notes................................................................................................... 31 1 S olar on Superstores
Executive Summary
S
olar energy is expanding rapidly across the
United States – increasing more than 100-fold
over the past decade. But, there are still many
untapped opportunities to harness the nation’s near-
ly limitless solar potential. The United States has the technical potential to produce more than 100 times
as much electricity from solar photovoltaic (PV) and
concentrating solar power (CSP) installations as the
nation consumes each year. Given our abundant solar
resources, America must take advantage of untapped
opportunities to install solar technologies – like using rooftops of large superstores and “big box” retail
stores as hosts for clean electricity generation.
The roofs of these large stores are perfect locations
for solar panels – they are largely flat and vacant and almost always fully exposed to the sun. The big box
stores, large grocery stores and malls considered in
this report account for 5 percent of electricity use in the United States. Solar panels produce energy that
can offset this large electricity demand while con-
tributing to a cleaner grid. Rooftop solar power also
brings benefits to the communities in which it is situ- ated. By producing electricity close to its final point of use, distributed rooftop power reduces costs and
energy losses associated with electricity transmission
and distribution.
Figure ES-1: Potential Solar PV Capacity on Big Box Stores and Shopping Centers, by State (Megawatts)
Executive Summary 2
Figure ES-2: Annual Reductions in Global Warming Pollution with Solar Panels on Available Big Box Stores and Shopping Centers by State (Metric Tons CO2) According to the National Renewable Energy Labo-
ratory (NREL), the United States has the technical
potential to generate enough electricity from rooftop
solar installations alone to meet nearly a quarter of
the nation’s electricity demand. The United States has
more than 102,000 big box retail stores, supercenters,
large grocery stores and malls with more than 4.5 bil-
lion cumulative square feet of available rooftop space
on which solar panels could be installed.
The rooftops of America’s big box stores and shop-
ping centers could host 62.3 gigawatts (GW) of so-
lar photovoltaic capacity, equivalent to the amount
of electricity used by more than 7 million average
U.S. homes or more than 7,500 average Walmart
stores, and more than double the solar photovol-
taic capacity that has been installed in the U.S. to
date. (See Appendix B for state breakdowns.)
Putting solar panels on the nation’s big box grocery
and retail stores creates unique benefits for the envi- ronment, electricity customers and the large com-
mercial businesses themselves.
• Generating clean electricity from rooftop solar
panels on existing commercial buildings is good
for the environment. Installing 62.3 GW of
clean solar power on America’s big box stores
and shopping centers would reduce global
warming pollution by nearly 57 million metric
tons annually – equivalent to taking nearly 12
million passenger vehicles off the road.
• Rooftop solar power is good for the grid and
electricity consumers. Producing electricity on
rooftops, close to where the electricity will
be used, reduces losses that happen during
electricity transmission – losses that totaled
an estimated 203 million megawatt-hours
(MWh), or 5 percent of electricity sales in 2012.
Solar power also reduces costs by producing the
most electricity during the sunniest parts of the
3 S olar on Superstores
day, which are often when demand for electricity
peaks. This helps utilities avoid firing up expen-
sive, peaking power plants to meet the temporary
rise in demand.
• Putting solar panels on the roofs of big box stores
is good for business. Electricity produced by
rooftop panels on big box stores and shopping
centers could offset the annual electricity
use of these buildings by 42 percent, saving
these businesses $8.2 billion annually on their
electricity bills.
Many big box retail stores are already reaping the
benefits of installing solar power on their rooftops.
• Of the businesses evaluated by the Solar Energy
Industries Association (SEIA), Walmart, Costco,
Kohl’s, IKEA, and Macy’s were the retail giants with
the most solar capacity installed as of the end of
2015. Walmart has at least 142 MW of total on-site
installed solar capacity.
• From the same survey, the top 25 companies have
installed a total of 1,462 solar energy systems at
business locations across the United States.
• The 10 big box companies with the largest
amount of retail space in the U.S. – Walmart,
Target, Home Depot, Lowe’s, Sears Holdings
(including Sears and KMart), Macy’s, J.C. Penney,
Kohl’s, Costco, and TJX (including Marshall’s and
TJMaxx) – have enough rooftop space to host
approximately 17 GW of solar capacity on their
retail stores, or nearly three quarters of the United
States’ current solar PV capacity.
• Solar-powered businesses are saving money on
their electricity bills and contributing to a cleaner
and more resilient electricity grid. By install-
ing solar panels on two California stores, Costco
reported savings of $300 per day on average over
three months.
Implementing local, state and federal policies that
promote the growth of rooftop solar power – like
net metering, third-party financing, community solar
power programs, streamlined solar permitting and
interconnection and tax credits and incentive pro-
grams for new solar energy markets – can spur the
development of rooftop solar power on America’s big
box stores and help America reach its solar poten-
tial. Officials at all levels of government should
implement solar-friendly policies that help to
accelerate adoption of solar energy by America’s
businesses.
Introduction 4
Introduction
S
wedish retailer IKEA is known for many things
– its bold blue store buildings, build-it-yourself
furniture, and store restaurants stocked with
Scandinavian treats.
Clean energy might not be the first thing that comes
to mind when consumers think of IKEA, but the
company is working to change that by adopting bold
goals for renewable energy installations on its stores
– including solar power installations.
IKEA’s adoption of renewable energy is driven by
high goals that the company has set for its busi -
ness practices. According to the company’s “People
and Planet Positive” sustainability strategy, IKEA is
committed to generating more renewable energy
than it consumes in its buildings and daily opera -
tions by 2020.
1 Of companies evaluated by the Solar
Energy Industries Association (SEIA) in 2014, IKEA
had the highest percentage of U.S. facilities with
solar panels.
2 Today, IKEA ranks sixth among U.S.
companies with more than 41 MW of total rooftop
solar installed. 3
According to a recent IKEA report on the company’s
sustainability practices, increasing reliance on solar
power and renewable energy is both good for the
environment and good for business: “This is good
for people and the planet and makes good business
sense, because it cuts costs and makes us resilient to
fluctuating energy prices.”
4 The business case that is motivating IKEA to “go so-
lar” – stable energy costs, improving financial returns from solar energy investments, and the imperative
to reduce business and regulatory risks related to cli- mate change – also holds true for retailers and other
businesses across the United States.
Big box retailers throughout the nation are begin-
ning to implement solar power on their vast, open
rooftops, benefiting themselves and the environ-
ment. In places where local, state and federal officials have implemented policies that help business owners
make sustainable energy choices, solar power is
becoming an increasingly common option for com-
mercial facilities.
This report will outline the vast rooftop solar po-
tential represented by U.S. big box stores and the
benefits of commercial rooftop solar power to these
businesses and the larger community, and discuss the
ways in which governments can encourage increased
solar power adoption in the commercial retail sector.
5 S olar on Superstores
Large Commercial Buildings Can Be
a Significant Source of Solar Energy
T
he amount of solar energy in the United
States has increased exponentially over the
last decade, but the nation has barely begun
to harness the nearly limitless amount of energy
that it receives from the sun. We can use our existing
structures to generate clean, local electricity by put- ting solar panels on the large, flat rooftops of com-
mercial big box stores.
The United States Has Vast Solar
Energy Potential
The United States receives more than enough energy
from the sun to meet the nation’s electricity needs.
Putting solar panels on big box stores is an important
step towards harnessing our solar potential and meet-
ing the nation’s electricity demand with clean energy.
Figure 1: Every State Can Meet Its Electricity Demand with Solar Power 6 Large Commercial Buildings Can Be a Significant Source of Solar Energy 6 Every State Can Meet Its Electricity
Needs with Solar Energy
The United States has the technical potential to pro-
duce more than 100 times as much electricity from
solar photovoltaic (PV) and concentrating solar power
(CSP) installations as the nation consumes each year,
and every state has the technical potential to meet its electricity demand with solar power.
5 (See Figure 1.)
The United States Has 100 Times More Solar
Photovoltaic Capacity Than It Had in 2005
Solar power is taking off across the nation. At the end of the third quarter of 2015, the United States had
more than 24 gigawatts (GW) of installed solar pho-
tovoltaic (PV) electric capacity, more than 12 times as much solar PV capacity as was installed in the coun-
try at the end of 2010.7 (See Figure 2.)
Solar power made up 30 percent of all new electricity
generating capacity that came online in the United
States in the first three quarters of 2015.9 Given the
exponential growth that solar power is experiencing,
it is quickly becoming a significant source of Ameri-
ca’s electricity generation.
Solar Energy Costs Continue to Fall
The costs of solar panels have fallen year after year in every sector – for residential, commercial and utility
scale installations.10 (See Figures 3 and 4.)
Installing solar panels on commercial rooftops is be-
coming increasingly affordable. The Solar Energy In-
dustries Association (SEIA) reported that the average
cost of a non-residential rooftop solar energy system
was $2.07 per Watt in Q3 2015, a 9 percent drop from
Q3 2014.12
Figure 2: Solar Power Is Growing Exponentially 8
-
5,000
10,000
15,000
20,000
25,000
30,000
35,000
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
Installed Photovoltaic Capacity (MWdc)
U.S. Cumulative Capacity
U.S. Annual Capacity Additions
E
7 S olar on Superstores
Commercial Rooftops Can Host a
Large Amount of Solar Energy
According to the National Renewable Energy Labo-
ratory (NREL), the United States has the technical
potential to generate enough electricity from rooftop
solar installations alone to meet nearly a quarter of
the nation’s electricity demand.
13 Commercial build-
ings make up an important part of this potential roof-
top market for solar power. As we define them in this
report, the United States has more than 102,000 “big
box” retail stores, supercenters, large grocery stores
and malls with rooftop space that could host solar
panels.
14 These stores are spread across the United
States. (See Table 1.)
Big box retail stores, many of which are household
names across the country, represent a significant
number of U.S. stores. Superstores Walmart and Cost-
co and grocery giant Kroger are the nation’s three
largest retailers with 7 ,453 U.S. stores and $507 billion in sales. The top five department stores – Macy’s,
Kohl’s, Sears Holdings, Nordstrom, and J.C. Penney
Co. – have 4,037 U.S. stores. The top five electronics
and entertainment stores – Best Buy, the Apple Store,
AT&T Wireless, Verizon Wireless and Toys “R” Us –
have 1 1,987 U.S. stores. Bed Bath & Beyond and IKEA
are two of the largest home goods stores, with 1,503
stores in the United States.
15 Many U.S. businesses have already begun to
make significant investments in solar power. As
of mid-2014, the 4.5 gigawatts (GW) of commer -
cial solar power installed in the United States
accounted for 30 percent of the nation’s total
installed solar capacity.
16 Figure 3: The Cost of Residential and Commercial Solar PV Installations Continues to Fall 11 $0
$2
$4
$6
$8
$10
$12
$14
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
Median Installed Price per KW (2014$)
Residential
Non-Residential ≤500 kW
Non-Residential >500 kW
Large Commercial Buildings Can Be a Significant Source of Solar Energy 8 Solar Potential on America’s Big Box
Stores and Shopping Centers
The potential of the nation’s commercial buildings
to host solar panels is much larger than the capacity
that has already been installed. America’s big box
stores have more than 4.5 billion square feet of avail- able rooftop space on which solar panels could be
installed.
20 The rooftops of America’s big box stores and shop-
ping centers could host 62.3 gigawatts (GW) of so-
lar photovoltaic capacity, equivalent to the amount
of electricity used by more than 7 million average
U.S. homes or more than 7,500 average Walmart
stores, and more than double the solar photovol-
taic capacity that has been installed in the U.S. to
date.
21 (See Appendix B for state breakdowns.)
The big box retail stores, large grocery stores and
malls considered in this report account for 5 percent
of electricity use in the United States.22 Electricity
produced by rooftop solar panels on big box
stores and shopping centers could offset the
annual electricity use of these buildings by 42
percent, saving these businesses more than $8.2
billion annually on their electricity bills.
23 Much of the big box retail space in the United States is owned or operated in by a small number of large
retail companies. The 10 big box companies with the
largest amount of retail space in the U.S. – Walmart,
Table 1: Number and Average Size of Big Box Stores and Shopping Centers by Region Region Number of Big Box Stores Average Square Footage of Big Box Store Northeast 13,788 83,245
Midwest 15,991 86,138
South 45,932 74,726
West 26,436 85,909
Total 102,148 80,556
SEIA’s Solar Means Business
Report Reveals America’s Leading
Solar-Powered Companies
At the end of 2015, the Solar Energy Industries
Association (SEIA) released the fourth edition
of a report ranking top U.S. businesses for their
installed solar capacity.17 SEIA reached out to
Fortune 100 companies in the U.S. and other
businesses “with known solar portfolios” in order
to rank the companies by installed solar capac-
ity and by number of solar installations. Their
rankings show that major retailers in the United
States are installing a significant amount of solar
energy at their business locations.
According to the report, the 25 companies with
the most on-site solar capacity installed are
home to a combined 700 MW of solar capacity,
with Walmart, Prologis (an industrial real estate
company), Apple, Costco, and Kohl’s leading the
way. The 25 companies with the most total solar
installations are home to 1,462 individual sys-
tems, with Walmart, Walgreens, Kohl’s, Costco,
Macy’s and Prologis leading the way.
18 In the 2014 edition of its report, SEIA found that
IKEA had solar power installed on 87 percent of
its facilities, the highest percentage of any com-
pany evaluated.19
9 S olar on Superstores
Target, Home Depot, Lowe’s, Sears Holdings (includ-
ing Sears and KMart), Macy’s, J.C. Penney, Kohl’s,
Costco, and TJX (including Marshall’s and TJMaxx) –
have a combined 2 billion square feet of retail space
in the United States, twice the area of Manhattan.
24 These companies alone have the potential to host
approximately 17 GW of solar capacity on the roofs
of their retail stores, or nearly three quarters of the United States’ current solar PV capacity.
25 (See Appen-
dix B for expanded listing.)
These estimates of solar energy potential only
include the rooftop space on top of these stores.
Big box stores are often surrounded by parking lots
and other areas that could host solar energy produc-
tion. Solar panels are capable of providing shade in
parking lots, some of which span several acres, while
taking up no additional land and reducing vehicle
fuel consumption for air conditioning use.
26 Many
retailers and businesses also own large distribution
warehouses that, although not included in this analy-
sis, are also ideal locations for solar panels. By taking advantage of these additional opportunities for solar
power generation, big box stores and other retail
outlets could produce even more solar energy than is
estimated here.
Much of the retail space of large American retailers
is leased, not owned, meaning that in many cases
solar installations require the involvement of the
landlord. Creative financing options like Property
Assessed Clean Energy (PACE) financing can help
overcome some of the hurdles leased property
presents. (See “New Financing Tools Can Help Busi -
nesses Overcome Hurdles to Solar Adoption” for
more details.)
Figure 4: Potential Solar PV Capacity on Big Box Stores and Shopping Centers, by State (Megawatts)
Large Commercial Buildings Can Be a Significant Source of Solar Energy 10 Table 2. Solar Capacity Potential for America’s Top 10 Big Box Stores (Excluding Grocery-Specific Chains) Solar
Potential
Rank
Company U.S. Retail Space
(Million Sq. Feet)
Potential
Rooftop Solar
Capacity (MW)
Equivalent to Power Consumed
by XX Thousand Households
(National Avg. Household Power
Use is 10.9 MWh/yr)
1 Walmart 680 5,844 660
2 Target 240 2,062 233
3 Home Depot 206 1,767 200
4 Lowe's Companies 196 1,683 190
5 Sears Holdings
(Sears and KMart) 188 1,614 182
6 Macy's 147 1,267 143
7 J.C. Penney Co. 111 950 107
8 Kohl's 84 720 81
9 Costco 70 601 68
10 TJX (Marshall's
and TJMaxx) 62 530 60
11 S olar on Superstores
Walmart: The Nation’s Largest Retailer and
Commercial Rooftop Solar Power Producer
Solar panels on a Walmart in Buckeye, Arizona. Credit: Walmart via Flickr, CC-BY 2.0 Walmart is the largest retail store chain in the
United States – and the leading big box store for
installed solar generation capacity. Walmart began
installing solar panels on its stores in 2005, and
the company has now installed 142 megawatts of
solar capacity across 348 locations (at stores and
distribution centers).
27 Each installation offsets 15 to
30 percent of the electricity needs of the store on
which it is sited.28 According to the Environmental
Protection Agency’s Green Power Partnership rank-
ings of organizations and governments using clean
power, Walmart ranks third among retail stores,
using 315,000 MWh of solar and wind generated
electricity annually.
29 More than 200 of Walmart’s solar installations
have been completed in partnership with the so -
lar provider SolarCity, and Walmart has contracted
with the company to install new solar power sys -
tems in 36 states by 2018. Walmart has also been
a pilot tester of SolarCity’s energy storage systems
for businesses.
30 Walmart has committed to use 7 billion kWh of re-
newable energy at its facilities around the world and
to double the number of U.S. Walmart stores with
solar panels by 2020.31 With nearly 5,000 U.S. stores,
Walmart has the national presence to make a signifi-
cant impact on the electricity grid if it does so.32
The Benefits of Scaling Up Commercial Rooftop Solar Power 12 The Benefits of Scaling Up
Commercial Rooftop Solar Power
“G
oing solar” is good for big box stores,
good for local electric grids and good for
consumers. Studies show that the ben-
efits that solar power brings to the electricity grid, our communities and the environment far outweigh the
benefits solar panel owners receive through policies
such as net metering.33 Generating clean solar electric- ity on the rooftops of big box stores can protect all
electricity customers from volatile costs and unneces-
sary expenses, make our electric grid more resilient,
reduce climate-altering pollution and cut costs for the big box businesses themselves.
Big Box Solar Power Brings
Widespread Community Benefits
Reducing Global Warming Pollution
Increasing the amount of solar power used in the Unit-
ed States will decrease the global warming pollution
that comes from fossil fuel combustion. In 2014, the
United States emitted 5.6 billion metric tons of carbon dioxide, second only to China; coal-fired power plants
accounted for nearly one-third of those emissions.
34 Producing energy from natural gas leads to large emis- sions of methane, an extremely potent greenhouse
Figure 5: Annual State Reductions in Global Warming Pollution with Solar Panels on Available Big Box Stores and Shopping Centers (Metric Tons CO2) 13 S olar on Superstores
gas, during its production, transportation and storage
– emissions that largely negate the reduced carbon
dioxide emitted during combustion.35
Solar power generation produces no global warming
pollution. Even when emissions from manufacturing,
transportation and installation of solar panels are in- cluded, solar power produces 96 percent less global
warming pollution than a coal-fired power plant over
its entire life cycle, and 91 percent less global warm- ing pollution than a natural gas-fired power plant.36
By reducing the need for electricity from fossil fuel-
fired power plants and by not producing significant
global warming pollution itself, solar power reduces
the threat posed by global warming and helps to
clean the nation’s air.
Installing 62.3 GW of solar power on big box stores
and shopping centers would reduce global warming
pollution by nearly 57 million metric tons annually
Solar Thermal Technologies Can Expand the Potential of Commercial Buildings to Reduce Global Warming Pollution
Solar hot water on Vermont farm, credit: Alan D. Ford
Solar thermal technologies like solar water heat-
ing also have the potential to offset energy use on
America’s commercial buildings. According to the
National Renewable Energy Laboratory, the energy
savings potential of installing solar hot water heat-
ing systems on available residential and commercial
rooftops in the United States is equivalent to the an-
nual electricity consumption of Oregon or the elec-
tric output of five large power plants.
41 This would
lead to an estimated additional annual savings of
$8.4 billion in electricity costs and carbon dioxide
emissions reductions of 50 to 75 million metric tons
per year, or 2 to 3 percent of emissions from the resi- dential and commercial building sectors.
42 That’s the
equivalent emissions reduction of taking between
10 and 16 million cars off the road.43
A typical solar hot water system in the United States
offsets the water heating energy needs of a building
by 40 to 80 percent in the United States, and since
these systems usually take up less space that solar
panel installations they can be a viable option on
rooftops too small for photovoltaic systems.
44 Some
companies like Nextility offer solar hot water heating
systems to businesses and non-residential institu-
tions through a third-party power purchase agree-
ment (in which Nextility owns the solar thermal
heating system and charges a guaranteed rate to the
business on which the system is installed).
45 Although this report only discusses the solar PV
potential of America’s commercial rooftops, solar
thermal technologies enhance the opportunity to
use solar energy to offset commercial buildings’ en-
ergy consumption and greenhouse gas emissions.
The Benefits of Scaling Up Commercial Rooftop Solar Power 14 – equivalent to taking nearly 12 million passenger
vehicles off the road.37
Many major U.S. businesses are installing solar power
as part of their commitments to reduce global warm-
ing pollution. IKEA – the company with the highest
percentage of U.S. facilities with solar panels – an-
nounced in June 2015 that it will spend $1.13 billion
on fighting global warming and has committed to
eventually being powered by 100 percent renewable
energy.
38 In November 2015 Walmart announced
that it had fulfilled its 2010 commitment to cut 20
million metric tons of global warming pollution from
its business practices by the end of 2015, in part by
increasing its reliance on solar power.
39 Stop & Shop
is a New England grocery store chain with more than
400 stores and 63,000 employees. In 2008, the com-
pany made a commitment to “reducing their carbon
footprint by 20 percent by 2015.” In that pursuit, they have installed solar power systems on 38 stores, pro-
ducing enough clean electricity to power the equiva-
lent of 730 homes yearly.40
Creating a Resilient Electricity System
Rooftop solar energy also helps communities deal
with the erratic weather and climatic stresses exac-
erbated by global warming. If transmission lines are
disrupted from a severe storm or heat wave, solar
energy attached to batteries can, in some circum-
stances, help avoid blackouts.
46 Distributed solar
generation paired with microgrids – electricity sys-
tems that can operate independently of the central
grid and create intentional islands – can also keep the power on after severe weather events that disrupt
electricity transmission on the centralized grid.
47 Pairing smart inverter technology with solar panels
also improves grid resiliency, even without the use of
distributed energy storage.
48 Solar PV panels also reduce competition for scarce
water resources during times of drought, using far
less water than conventional fossil fuel and nuclear
power plants. The life-cycle water consumption of so-
lar photovoltaics is 1/500
th of the life-cycle water con-
sumption of coal power plants and 1/80th of that of
natural gas plants per unit of electricity produced.49
According to a study by the Union of Concerned
Scientists, a scenario with high levels of renewable
energy and energy efficiency would withdraw and
consume half the amount of water for electricity pro-
duction as a business-as-usual scenario.
50 Because solar PV panels do not rely on water for
electricity production, communities that generate
a significant amount of electricity from solar panels
are less susceptible to electricity disruption during
droughts. During the Midwest drought of 2012, many
fossil-fuel power plants that required cooling water
to operate were forced to limit or suspend electricity
production.
51 The California drought caused a drop
in hydroelectricity generation at the beginning of
2014, but the state’s solar energy helped to compen-
sate and guard against electricity outages.
52 Climate
change will only increase the risk of drought and
solar power can be a real solution to stabilize electric- ity production under these conditions.
Cutting Consumer Costs
Scaling up U.S. solar electricity generation would
deliver important benefits to homeowners and busi-
nesses, including low-income consumers. All elec-
tricity consumers would see less price volatility from
fossil fuels and reduced losses of electricity in trans- mission and distribution.
An electric grid that relies more on solar power and
less on fossil fuels can deliver electricity to all custom- ers with much less fossil-fuel related volatility in the price of electricity.
53 Rooftop solar panels also capture
the most solar energy during sunny periods of high
electricity demand when the cost of producing elec-
tricity is normally the highest – saving money for all
consumers on their power bills.
With smart public policies and declining prices, more
and more people have the opportunity to benefit
15 S olar on Superstores
from solar energy, including low-income households
and those living in multi-family housing. Low income
families participating in California’s Single-Family
Affordable Solar Homes program, for example, cut
their monthly electricity bills by 80 percent on aver-
age.
54 In multi-family homes, programs that allow for
“virtual net metering” can distribute the benefits of
one solar installation to multiple families in a hous-
ing complex. Virtual net metering enables shared,
community solar projects that allow those who are
unable to install solar panels on their own properties
or live in multi-family homes to “go solar.”55
Using more distributed solar power for U.S. electric-
ity production would also result in a more efficient
electric grid. The U.S. Energy Information Administra-
tion estimated that the United States lost about 203
million megawatt-hours (MWh) of electricity in 2012
during transmission, or 5 percent of the total amount
of electricity generated that year, leading us to gener- ate more electricity than we needed, increasing costs
for ratepayers and causing additional pollution.
56 Distributed solar energy on commercial rooftops
avoids these losses by generating electricity at or
near the location where it is used.57 This allows more
energy to go straight into homes and businesses, and
avoids high-cost investments in expanding transmis-
sion capacity.
Reducing Air Pollution
Installing solar energy on commercial rooftops can
improve air quality by reducing our reliance on pol-
luting fossil fuels for electricity. The United States
generates 67 percent of its electricity from fossil fuels, including coal, natural gas and oil. Almost 40 percent
of U.S. electricity came from coal in 2014.
58 Our out-
sized dependence on dirty fossil fuels for electricity
takes a toll on public health, as these energy sources
release known hazardous pollutants into the air.
Fossil-fuel fired power plants create 70 percent of U.S. sulfur dioxide emissions and 13 percent of nitrogen
oxide emissions, affecting air quality in ways that
harm human health.
59 Sulfur dioxide contributes to
the formation of acid rain, as well as small particles
in the air that can penetrate deep into the lungs and
trigger respiratory diseases such as bronchitis and
emphysema. Particulate pollution has been linked
to increased rates of hospital admissions and prema-
ture death.
60 According to an MIT study, fine particle
pollution caused 52,000 early deaths in the United
States in 2005.
61 Nitrogen oxides contribute to the
formation of ozone “smog.” Ozone reacts with airway
tissues and produces inflammation similar to sunburn
on the inside of the lungs. This inflammation makes
lung tissues less elastic, more sensitive to allergens
and less resistant to infections.
62 Creating Jobs
Installing more solar power is not only good for the
environment and for electricity consumers; it also
creates a significant number of local jobs that cannot
be outsourced.
America is already experiencing significant job
growth in the solar energy industry. Nearly 209,000
Americans worked in the solar energy industry as of
November 2015, a 20 percent increase from the previ-
ous year, according to The Solar Foundation’s annual
solar jobs census.
63 According to The Solar Founda-
tion, growth in the solar industry from November
2014 to November 2015 was nearly 12 times faster
than the national average employment growth rate.64
Solar industry investment in the U.S. economy is
almost $15 billion each year.65
The Benefits of Scaling Up Commercial Rooftop Solar Power 16 Big Box Stores Directly Benefit from
Hosting Solar Panels
Large commercial businesses use a significant
amount of electricity, taking a toll on the environ-
ment and their electricity bills. Electricity rates for commercial customers in the U.S. increased by 20
percent over the last 10 years.
66 On average, each of
the nation’s big box retail stores, large grocery stores and malls consumes 1,800 megawatt-hours of elec-
tricity annually and spends an average of $190,000 on
their electricity bill each year. Electricity produced by rooftop panels could offset the annual electricity use
of these buildings by 42 percent, saving these big box
stores $8.2 billion annually on their electricity bills.67 Solar businesses are saving money on their electricity
bills and contributing to a cleaner and more secure
electricity grid. By installing solar panels on two Cali- fornia stores, for example, Costco reported savings of
$300 per day on average over three months.68
Solar power provides some particular economic ben-
efits to big box stores and other businesses:
• Because big box stores generally use most of their
energy during the day, when the sun is shining,
they benefit from instantaneous use of the free
electricity solar panels generate. For businesses
planning their economic future, solar panels also
provide freedom from volatile energy prices –
whether they are installed through individual
financing or through a long-term power purchase
agreement.
• Solar panels paired with energy storage can
also reduce demand charges, which for some
businesses account for more than half of their
monthly electricity costs.
69 Demand charges,
which are calculated from peak load times rather
than monthly energy use, can be reduced by
smart battery installations that supply energy at
moments of high energy use.
70 • Solar panels can indirectly lower business cooling and heating costs by shading roofs during the day,
and providing insulation at night – benefits that
are particularly pronounced on older warehouse
buildings.
71 17 S olar on Superstores
Case Study 2: Clothing Retailers Macy’s,
Kohl’s and Target Invest in Solar Power
Macy’s in Irvine, California. Credit: Woolennium via Flickr, CC-BY-NC-ND 2.0 Major clothing retailers Macy’s and Kohl’s are mak-
ing significant investments in solar energy.
Among businesses surveyed in SEIA’s 2015 Solar
Means Business report, Kohl’s ranks fifth in the
country with more than 50 MW of solar power
installed on its stores.72 Kohl’s ranks first in the na- tion for green power purchasing according to the
Environmental Protection Agency – its purchases of
solar energy credits and the solar energy produc-
tion at its facilities offset 104 percent of the electric- ity demand at Kohl’s facilities.
73 Kohl’s has 161 solar
power systems on its stores in 13 states, each of
which offsets 20 to 50 percent of its store’s energy
use.74 Its largest project in Maryland consists of
more than 8,000 solar panels and generates more
than 3 million kWh of electricity annually.75
Macy’s has the seventh-highest amount of solar
capacity installed on its facilities, with 20.8 MW in
total.76 Macy’s has contracted with Sunpower to
install solar panels at 30 locations in California.77
By signing a power purchase agreement with
Sunpower in 17 of these 30 projects, Macy’s will
purchase the electricity generated by the panels
from Sunpower, which owns the panels.
78 This
kind of third-party agreement can help businesses
avoid the cost of purchasing the panels themselves,
making projects more affordable. These projects
alone will put 8.9 megawatts of solar power on
Macy’s stores and help the company reduce global
warming pollution from dirty electricity sources by
88,000 metric tons over 30 years.
79 As of December 2015, Target had nearly 15 MW of
installed onsite solar capacity at 41 different loca-
tions.80 In February 2015, Target announced plans
to install rooftop solar panels on 500 U.S. locations
by 2020, including plans to add solar panels to 250
Target buildings in 2015 and 2016 alone.81
New Financing Tools Can Help Businesses Overcome Hurdles to Solar Adoption 18 New Financing Tools Can Help
Businesses Overcome Hurdles to
Solar Adoption
T
he benefits of solar power are clear: it is good
for the environment and can save money.
Many businesses are eager to reap these
benefits, as demonstrated by companies like Ikea,
Walmart, Kohl’s, and Macy’s. But important hurdles
often stand in the way of commercial solar energy
installations – barriers that can be overcome with
smart public policy.
Efforts to install solar energy on commercial build-
ings often fall victim to the inherent complexity of
commercial contracts and to misaligned incentives
between building owners and retail chains. Another
set of challenges is in the financing realm, which for
commercial customers tends to be more complicated
and less standardized than for residential solar.82 The good news is that new financing mechanisms and
risk analysis tools are being developed and rolled out
that can solve some of the problems of commercial
solar development:
• Lack of standardization for commercial solar lease
and power purchase agreements can increase
the cost and hassle of “going solar” for businesses.
The Solar Access to Public Capital (SAPC) working
group, a project of the National Renewable Energy
Laboratory (NREL), has worked with hundreds of
stakeholders to develop standardized commercial
power purchase agreements and lease agree-
ments. NREL ’s stated goals for SAPC include
minimizing due diligence cost and time, and
opening the solar market to investment mecha-
nisms including securitization.
• Many banks will not finance solar projects because
there are not established standards for measuring
risk and investment return.
83 The truSolar initiative,
introduced by Distributed Sun, DuPont and the
Rocky Mountain Institute in September 2012, aims
to fix those problems by creating a standard ranking
system for all of the elements in a solar project.
84 • Businesses often lease their property, with many
businesses unable to make long-term commit-
ments that would extend over the 15- to 20-year
lifetime of a solar energy system. Financing options
like Property Assessed Clean Energy (PACE) financ-
ing, in which the obligation to repay a solar loan
passes to the new owner when a property is sold,
can ease risk in these cases. (See more on PACE in
“Policy Recommendations, ” next page.)
As national retailers and big box stores “go solar,”
these large businesses can help solidify the commer-
cial solar market, bringing about increased standard-
ization while also lowering their own energy costs
and reducing global warming emissions.
19 S olar on Superstores
Policy Recommendations
P
olicies that support rooftop solar power bring
the additional environmental, economic and
social benefits of local, distributed electricity
to America’s communities. Officials at all levels of
government must implement solar-friendly poli-
cies that help to accelerate America’s commercial
solar energy adoption. These should include:
• Adopting and preserving strong interconnection
and net metering policies – These policies ensure
that businesses are appropriately compensated
for the electricity that they export to the grid,
allow them to move seamlessly between produc-
ing their own electricity and using electricity from
the grid, and make solar power an affordable
business investment for big box stores. In states
or utility territories without strong net metering
programs, carefully implemented CLEAN contracts
(also known as feed-in tariffs) and value-of-solar
payments can play an important role in ensur-
ing that consumers receive a fair price for solar
energy, so long as the payments fully account for
the benefits of solar energy and are sufficient to
spur participation in the market.
• Extending or maintaining state-level solar energy
tax credits – State level tax credits for solar energy
are important supports for state commercial solar
energy markets. States should offer property
tax exemptions that exclude the value of solar
equipment from the assessed property value
on which homeowners and business owners
must pay taxes. States should also offer sales tax
exemptions for the sale of solar panels and solar
hot water heating equipment, which lowers the
up-front cost of buying the equipment.
• Enabling third-party sales of electricity – Although businesses that choose to purchase their own
solar panels can reap the benefits of faster installa-
tion and no monthly payments, alternate “third-
party” financing options – like power-purchase
agreements and solar leases – have been a partic-
ularly important way for businesses to install solar
panels on a large scale. These arrangements allow
third-party companies to own the panels and help
businesses avoid the high up-front costs of solar
panel purchases. States should allow companies
that install solar panels to sell electricity to their
customers without subjecting them to the same
regulations as large public utilities.
• Adopting financing programs like Commercial PACE–
Creative financing options that provide businesses
with low up-front costs and long-term repayment
options are important for the commercial solar
industry. For example, commercial Property-
Assessed Clean Energy (PACE) financing programs
allow local governments to pay the up-front cost
of commercial solar projects, with the expenses
repaid by the businesses in their property taxes.
85 • Allowing and encouraging community solar
programs – Community solar programs allow
people who may not be able to install solar panels
themselves to invest in a solar installation sited
away from their private properties and share
credit for the electricity produced by the solar
panels and sent back to the electric grid.
86 Partner-
ing with businesses and non-profit organizations
to establish a community solar projects at the
local level can be a creative source of financing for
solar projects on commercial rooftops.
87 Policy Recommendations 20
• Streamlining solar permitting and instituting afford- able permitting fees – The “soft costs” associated with solar power – costs such as those associated with
installing the system, completing paperwork, and
paying taxes and permitting fees – typically make
up more than half of the total cost of an installed
commercial solar energy system.
88 Local govern-
ments should work to reduce these costs, accelerate
the time it takes to obtain a permit for a solar instal- lation, ensure that permitting rules do not hinder
the installation of solar panels, and streamline the
paperwork necessary to get a permit.
• Encouraging electric utilities to adopt solar-friendly rate structures – Under some rate structures,
utilities bill electricity customers in a way that
minimizes the savings that they can recoup from
rooftop solar energy generation.
89 Regulators
should investigate the impacts of rate plans on
solar energy adoption and support those that
improve the economics of installing solar power
for business owners.
• Enforcing the requirements of the Clean Power
Plan – The federal government should enforce
the standards of the Clean Power Plan to reduce
global warming emissions 30 percent below 2005
levels by 2030. It should also emphasize programs
like the Clean Energy Investment Program, which
incentivizes the states’ early deployment of solar,
wind and low-income energy efficiency. States
should establish effective plans for meeting or
surpassing the goals of the Clean Power Plan,
with clean and renewable sources of energy such
as solar power playing a leading role. Investing
in commercial solar power will play a key role in
reaching the levels of renewable energy adoption
that will be necessary to reach these goals.
21 S olar on Superstores
Appendix A: Methodology
Solar Capacity and Generation on
Commercial Buildings
To estimate the technical potential for solar PV
systems on large commercial buildings in the United
States, we used the U.S. Energy Information Adminis-
tration’s 2012 Commercial Building Energy Consump-
tion Survey (CBECS) to determine the square footage
of large commercial buildings. We defined large
commercial buildings using CBECS microdata and
the following selection criteria in order to capture
large “big box” retail and grocery store buildings
that could host solar panels: buildings over 25,000
square feet with the principal building activities of
“food sales,” “strip shopping malls,” “retail (other than mall),” and “enclosed mall.” We excluded buildings of
these types with more than 15 floors. This left us with 102,147 big box retail stores, grocery stores and malls to evaluate.
The tables below display characteristics of these big
box stores by building activity type and region.
Table A-1: Number of Big Box Buildings and Shopping Malls by Region and Building Activity Type Region Food Sales Strip Shopping Malls Enclosed Malls Retail (Other than Malls) Grand Total
Northeast 3,124 6,386 109 4,169 13,788
Midwest 802 7,872 198 7,119 15,991
South 2,222 25,148 497 18,065 45,932
West 2,822 12,950 266 10,398 26,436
Grand Total 8,971 52,356 1,070 39,750 102,148
Table A-2: Total Square Footage of Big Box Buildings and Shopping Malls by Region and Building Activity Type (Millions of Square Feet) Region Food Sales Strip Shopping Malls Enclosed Malls Retail (Other than Malls) Grand Total
Northeast 185 556 93 314 1,148
Midwest 29 655 147 546 1,377
South 78 1,828 334 1,192 3,432
West 207 926 244 895 2,271
Grand Total 499 3,965 819 2,947 8,229
Appendix A: Methodology 22
Using Microsoft Access, we used CBECS microdata to
divide the total floor space in each building by the
number of floors in each building. This gave us an
estimate of rooftop space available on each building
and of total rooftop space on large commercial build-
ings in each U.S. census division.
We then apportioned the total rooftop space on big
box stores in each region to each state according
to the percentage of the regional population living
in each state in 2012 using the U.S. Census Bureau’s
American Community Survey 5-Year Estimates.
This yielded 7 .2 billion square feet of rooftop area on the selected large retail, grocery store and shopping
mall buildings in the United States. We assumed that
65 percent of this rooftop area is suitable for rooftop solar energy systems in designated “cool” climates
and 60 percent in “warm” climates, per a 2008 study
by Navigant Consulting for the National Renewable
Energy Laboratory, Rooftop Photovoltaics Market
Penetration Scenarios.
90 In calculating this number,
Navigant took into account factors such as trees and
other shading on residential and larger buildings,
roof tilt and orientation, and the room needed on
roofs between solar panels and taken up by other
objects such as chimneys and fan systems.
This yielded 4.5 billion square feet of rooftop area
available and appropriate for rooftop solar PV sys-
tems. We assumed solar panel efficiency of 18.5
percent, per the 2008 Navigant Consulting report for
the National Renewable Energy Laboratory, Rooftop
Photovoltaics Market Penetration Scenarios.
91 This
efficiency corresponds to an estimated solar power
density on commercial buildings of 13.7 megawatts
per million square feet of available rooftop space, ac- counting for space needed for ancillary equipment.
92 This yielded the result that these commercial roof-
tops could host 62.3 gigawatts of solar PV capacity.
To estimate electricity generation from rooftop solar
panels on big box stores in each state, we used state-
specific rooftop solar PV capacity factors implied by
the data in the National Renewable Energy Laborato-
ry’s U.S. Renewable Energy Technical Potentials report.93 (NREL ’s capacity factor accounts for DC-AC inverter
efficiency, as well as losses associated with wiring,
maintenance and other factors.)94 We multiplied the
potential big box store solar capacity in each state by the solar capacity factors reported by NREL and the
number of hours in a year to estimate the solar gen-
eration by state by year. For Alaska and Hawaii, we
used the national average capacity factor based on
the NREL data, as specific estimates of rooftop solar
generation in these states were unavailable.
A similar methodology was used to calculate the
potential solar capacity of individual big box store
companies in Table 2. Because there are no available
estimates of rooftop space for each company listed,
Table A-3: Total Estimated Rooftop Square Footage by Region and Building Activity Type (Millions of Square Feet)
Region Food Sales Strip Malls Enclosed Malls Retail (Other than Malls) Grand Total
Northeast 185 504 41 248 978
Midwest 19 587 101 485 1,192
South 70 1,678 273 1,066 3,087
West 175 884 130 806 1,996
Grand Total 449 3,653 546 2,605 7,253
23 S olar on Superstores
we assumed that retail space is equivalent to total
rooftop space. For big box retailers where the major-
ity of locations are single-floor standalone retail loca- tions, this calculation may result in an underestimate
of total rooftop space because retail space does not
include the parts of a building devoted to warehous-
es, shipping and packing, or office space. For retailers whose stores tend to have more than one floor, or
are located within a multi-story mall, this calculation may result in an overestimate of total roof space. We
assumed that 62.5 percent of each store’s calculated
total rooftop space is available for rooftop solar en-
ergy systems, based on the average of warm and cool
climate available space factors in the previously cited Navigant/NREL report, Rooftop Photovoltaics Market
Penetration Scenarios. Based on the same report, we
calculated that 13.7 MW of solar capacity could be
installed per million square feet of available space.
Electricity Consumption of
Big Box Stores
To estimate the electricity consumption and annual
electricity expenditures of big box stores in each
state, we calculated electricity consumption statistics by building activity type and region from the 2003
Commercial Building Energy Consumption Survey
(CBECS) and applied those to buildings of the same
type and within the same region in the 2012 CBECS.
This estimate was necessary because the U.S. EIA has
not yet released updated 2012 statistics on energy
consumption of commercial buildings (as of De-
cember 2015); only the data on commercial building
characteristics has been released (which we used to
estimate rooftop space on big box stores). We then
apportioned the estimated electricity consumption
of big box stores in each region to each state accord-
ing to the percentage of the region population living
in each state in 2012 using the U.S. Census Bureau’s
American Community Survey 5-Year Estimates.
To estimate annual electricity expenditures by big
box stores in each state, we multiplied our state-spe-
cific estimates of big box store electricity consump-
tion by 2013 state commercial electricity rates.
95 Global Warming Emissions
Reductions
When solar panels generate electricity, they displace
some other source of electricity on the grid. The type
of electricity production that is offset by solar power depends on several factors: regional variations in the
electricity resource mix, the degree to which solar
energy offsets new versus existing generation capac-
ity, the relative price of competing forms of electric- ity generation (including marginal prices), and the
way in which solar energy is integrated into the grid,
among others.
To estimate carbon dioxide emission reductions
from solar energy generation on big box stores, we
assumed that solar energy added to the grid would
offset fossil fuel generation only, and would offset
coal and gas-fired generation in proportion to their
contribution to each state’s particular electricity mix, as defined by the regional electricity grids that serve that state.
Emission reduction rates for each state were based
on the actual electricity generation mixes in 2013 for
the EIA EMM regions of which they are a part. The
EIA’s Annual Energy Outlook 2015 provided data on
actual annual electricity generation and emissions for
coal and natural gas power plants in each EIA region
in 2013 (compiled from EIA Form 759). We assigned
each EMM region to one of the interconnection
regions identified by the North American Electric
Reliability Corporation (NERC), using maps of EMM re-
gions and NERC regions. We estimated an emissions
factor for fossil fuel-fired generation for each NERC
region, using the generation and emissions data for
the constituent EMM regions.
To arrive at an emissions factor for each state, we
determined the percentage of electricity sales in each
state that come from within each NERC region, using
data from U.S. Department of Energy, Energy Infor-
mation Administration, Electric Power Sales, Revenue,
and Energy Efficiency Form EIA-861, 29 October 2013.
State emission factors were created by multiply-
Appendix A: Methodology 24
ing each state’s percent of sales per NERC region in
2012 by each region’s emission factor. The use of a
constant emission factor for each state masks hourly
variations in the carbon intensity of electricity on the grid, meaning that the estimates in this report do not
fully reflect the ways in which additional solar energy might affect hourly dispatch of different electricity
generators in each region of the country.
NERC regions could not be identified for utilities
responsible for a total of 1.5 percent of electricity sales nationally, including for the states of Alaska and Ha-
waii. For the state of Alaska, we divided annual carbon dioxide emissions from coal and natural gas sources in
the electric power industry by total electricity genera- tion from coal and natural gas sources in the electric
power industry. For the state of Hawaii, most electricity is generated from petroleum (70 percent of electricity
generated in 2013 came from petroleum sources). For
that reason, we calculated Hawaii’s emission factor by
dividing annual carbon dioxide emissions from petro-
leum by annual electricity generation from petroleum.
For both Alaska and Hawaii, we used the 2012 emission
factor for 2013, based on available data.
96 To estimate total emissions savings numbers for each state, we multiplied big box store solar generation for that scenario by the emission factor for that state and year. National estimates for each year were based on
a sum of all state estimates.
25 S olar on Superstores
Appendix B: Tables
Table B-1: Solar Potential on Big Box Stores, By State97 State
Big Box Store
Rooftop Space
(million ft2)
Potential Solar Capacity
on Big Box Stores (MW)
Annual Potential
Big Box Solar
Generation by
State (GWh)
Equivalent to Power
Consumed by XX
Thousand Households
(National Avg
Household Power
Use is 10.9 MWh/yr)
By XX Wal-Marts
(10,320 MWh/year)
Alabama 129 1,056 1,306 120 127
Alaska 20 175 216 20 21
Arizona 178 1,459 2,230 205 216
Arkansas 78 699 875 80 85
California 1,034 8,497 11,911 1,093 1,154
Colorado 140 1,244 1,704 156 165
Connecticut 63 562 630 58 61
Delaware 24 216 251 23 24
District of
Columbia 16 145 172 16 17
Florida 508 4,176 5,408 496 524
Georgia 261 2,148 2,716 249 263
Hawaii 38 310 382 35 37
Idaho 43 387 486 45 47
Illinois 228 2,033 2,325 213 225
Indiana 115 1,028 1,187 109 115
Iowa 54 483 581 53 56
Kansas 51 452 590 54 57
Kentucky 117 1,040 1,215 111 118
Louisiana 122 1,002 1,215 111 118
Maine 23 209 239 22 23
Maryland 156 1,386 1,616 148 157
Massachusetts 116 1,032 1,173 108 114
Michigan 176 1,569 1,716 157 166
Minnesota 95 842 966 89 94
Mississippi 80 656 811 74 79
Missouri 107 949 1,172 108 114
Appendix B: Tables 26
State
Big Box Store
Rooftop Space
(million ft2)
Potential Solar Capacity
on Big Box Stores (MW)
Annual Potential
Big Box Solar
Generation by
State (GWh)
Equivalent to Power
Consumed by XX
Thousand Households
(National Avg
Household Power
Use is 10.9 MWh/yr)
By XX Wal-Marts
(10,320 MWh/year)
Montana 27 244 286 26 28
Nebraska 33 290 366 34 35
Nevada 75 616 929 85 90
New
Hampshire 23 207 231 21 22
New Jersey 155 1,384 1,593 146 154
New Mexico 57 468 722 66 70
New York 343 3,052 3,493 320 338
North Carolina 257 2,286 2,813 258 273
North Dakota 12 107 127 12 12
Ohio 205 1,829 2,001 184 194
Oklahoma 101 898 1,197 110 116
Oregon 106 946 1,004 92 97
Pennsylvania 224 1,998 2,230 205 216
Rhode Island 19 166 185 17 18
South Carolina 125 1,024 1,280 117 124
South Dakota 15 129 160 15 16
Tennessee 171 1,522 1,846 169 179
Texas 678 5,574 7,282 668 706
Utah 77 682 908 83 88
Vermont 11 98 107 10 10
Virginia 216 1,920 2,290 210 222
Washington 187 1,662 1,675 154 162
West Virginia 50 443 491 45 48
Wisconsin 101 902 1,025 94 99
Wyoming 16 139 184 17 18
United States 7,253 62,341 77,515 7,111 7,511
Table B-1 (continued): Solar Potential on Big Box Stores, By State97 27 S olar on Superstores
Table B-2: Electricity Savings, Money Savings and Emissions Reductions from Solar Power on Big Box Stores, by State
State
Global Warming Pollution
Offset by Reaching Big
Box Store Solar Potential
(thousand metric tons CO2)
Could Offset XX Percent of Big Box
Store Electricity Usage in State
Could Save $XX on Annual
Electricity Spending (millions of $)
Alabama 1,037 39% $137
Alaska 151 45% $34
Arizona 1,578 51% $220
Arkansas 709 42% $70
California 8,484 47% $1,694
Colorado 1,203 50% $168
Connecticut 313 34% $92
Delaware 219 39% $26
District of Columbia 151 40% $21
Florida 3,097 40% $508
Georgia 2,153 39% $271
Hawaii 301 41% $130
Idaho 338 45% $36
Illinois 1,927 47% $189
Indiana 1,023 47% $114
Iowa 554 49% $49
Kansas 498 54% $57
Kentucky 991 39% $104
Louisiana 981 38% $109
Maine 119 35% $28
Maryland 1,412 39% $173
Massachusetts 574 35% $167
Michigan 1,490 45% $190
Minnesota 919 47% $91
Mississippi 645 39% $82
Missouri 943 51% $103
Appendix B: Tables 28
State
Global Warming Pollution
Offset by Reaching Big
Box Store Solar Potential
(thousand metric tons CO2)
Could Offset XX Percent of Big Box
Store Electricity Usage in State
Could Save $XX on Annual
Electricity Spending (millions of $)
Montana 208 42% $27
Nebraska 345 52% $31
Nevada 661 50% $84
New Hampshire 114 34% $31
New Jersey 1,377 35% $204
New Mexico 543 52% $70
New York 1,714 35% $536
North Carolina 2,225 42% $246
North Dakota 122 49% $11
Ohio 1,735 45% $187
Oklahoma 1,013 45% $93
Oregon 717 38% $87
Pennsylvania 1,941 34% $206
Rhode Island 92 34% $24
South Carolina 1,018 39% $126
South Dakota 148 51% $14
Tennessee 1,477 41% $185
Texas 4,466 41% $584
Utah 639 48% $76
Vermont 52 33% $16
Virginia 1,856 40% $183
Washington 1,192 36% $130
West Virginia 428 37% $40
Wisconsin 944 47% $110
Wyoming 130 48% $16
United States 56,965 42% $8,180
Table B-2 (continued): Electricity Savings, Money Savings and Emissions Reductions from Solar Power on Big Box Stores, by State 29 S olar on Superstores
Table B-3: Solar Capacity Potential for America’s Top 24 Big Box Stores (Excluding Grocery-Specific Chains) 98 Solar
Potential
Rank
Company U.S. Retail Space
(million sq feet)
Potential
Rooftop Solar
Capacity (MW)
Equivalent to Power Consumed
by XX Thousand Households
(National Avg Household
Power Use is 10.9 MWh/yr)
1 Walmart 680 5,844 660
2 Target 240 2,062 233
3 Home Depot 206 1,767 200
4 Lowe's Companies 196 1,683 190
5 Sears Holdings (Sears and KMart) 188 1,614 182
6 Macy's 147 1,267 143
7 J.C. Penney Co. 111 950 107
8 Kohl's 84 720 81
9 Costco 70 601 68
10 TJX (Marshall's and TJMaxx) 62 530 60
11 Burlington Coat Factory 42 363 41
12 Best Buy 40 347 39
13 Office Depot 37 314 35
14 Bed Bath & Beyond 32 277 31
15 Dick's Sporting Goods 32 272 31
16 Menard 30 257 29
17 Gap (Gap, Banana Republic, Old Navy,
Piperlime, Athleta, and Intermix) 29 252 28
18 Nordstrom 27 231 26
19 Staples 25 211 24
20 Ascena Retail Group (Lane
Bryant, maurices, dressbarn,
Catherines and justice)
21 179 20
21 BJ's Wholesale Club 21 177 20
22 IKEA 12 106 12
23 Toys "R" Us 5 42 5
24 Foot Locker 4
36 4
Total 2,339 20,103 2,271
Appendix B: Tables 30
Table B-4: Solar Capacity Potential for Top Big Box Stores with Current Installed Solar Capacity for Comparison 99
Solar
Potential Rank Company U.S. Retail Space
(million sq feet)
Potential Rooftop
Solar Capacity (MW)
Existing Solar Capacity (MW)
(From SEIA Solar Means Business
2015, where available)
1 Walmart 680 5,844 141.99
2 Target 240 2,062 14.94
6 Macy's 147 1,267 20.78
8 Kohl's 84 720 50.21
9 Costco 70 601 50.75
14 Bed Bath & Beyond 32 277 17.34
19 Staples 25 211 13.66
22 IKEA 12 106 41.41
31 S olar on Superstores
Notes
1 I KEA, People & Planet Positive: IKEA Group
Sustainability Strategy for 2020, accessed at web.archive. org/web/20150706064018/http://www.ikea.com/ms/en_
GB/pdf/people_planet_positive/People_planet_positive.
pdf, 5 July 2015.
2 S olar Energy Industries Association, Solar Means
Business 2014: Top U.S. Commercial Solar Users, 2014.
3 S olar Energy Industries Association, Solar Means
Business 2015: Top U.S. Commercial Solar Users, 2015.
4 I KEA, Sustainability Report FY15, available at
ikea.com/ms/en_US/img/ad_content/2015_IKEA_
sustainability_report.pdf, 2015.
5 T his includes potential solar power generation
from rooftop solar panels, large utility-scale solar instal- lations, and concentrating solar power plants. Judee Burr and Lindsey Hallock, Frontier Group, Rob Sargent, Environ- ment America Research & Policy Center, Star Power: The
Growing Role of Solar Energy in America, November 2014. 6 I bid.
7 S EIA, U.S. Solar Market Insight: U.S. Installs 1.3 GW in Q3, Headed Toward Record-Breaking 2015, archived at
web.archive.org/web/20160201203850/http://www.seia.
org/research-resources/us-solar-market-insight.
8 H istoric capacity: Shayle Kann et al., GTM Re -
search and SEIA, U.S. Solar market insight report - 2014 year in review, 10 March 2015; 2015 capacity additions: 2015 ca- pacity additions are based on preliminary estimate (noted “E”) of 7.4 GW solar additions in 2015: SEIA, U.S. Solar Market Prepares for Biggest Quarter in History, available at seia.org/news/us-solar-market-prepares-biggest-quarter- history, 9 December 2015.
9 S hayle Kann et al., GTM Research and SEIA, U.S. Solar Market Insight Executive Summary Q3 2015, December 2015. 10 U tility-scale installations are considered to be
those larger than 1 MW in size.
1 1 G alen Barbose and Naïm Darghouth, Lawrence
Berkeley National Laboratory, Tracking the Sun VIII: The In- stalled Price of Residential and Non-Residential Photovoltaic Systems in the United States, August 2015.
12 Q 3 2015 data: Shayle Kann et al., GTM Research
and SEIA, U.S. Solar Market Insight Executive Summary Q3 2015, December 2015; Q3 2014 data: Shayle Kann et al.,
GTM Research and SEIA, U.S. Solar Market Insight Executive Summary Q3 2014, 2014.
13 2 2 percent: Anthony Lopez et al., National Renew - able Energy Laboratory, U.S. Renewable Energy Technical Potentials: A GIS-Based Analysis, July 2012, and U.S. Energy Infor- mation Administration, State Electricity Profiles: Data for 2012, 1 May 2014, accessed at http://www.eia.gov/electricity/state. 14 Se e methodology.
15 N ational Retail Federation, Top 100 Retailers, ac- cessed at web.archive.org/web/20150703213447/https://
nrf.com/2015/top100-table, 3 July 2015.
16 “ As of mid-2014, there were 4,531 MW of com -
mercial solar PV installed on 41,803 business, non-profit and government locations throughout the U.S.”: Solar Energy Industries Association, Solar Means Business 2014: Top U.S.
Commercial Solar Users, 2014. Cumulative PV capacity as of mid-2014 was 15 GW: Solar Energy Industries Association, Solar Market Insight Report 2014 Q2, 2014, available at web. archive.org/web/20150703181134/http://www.seia.org/
research-resources/solar-market-insight-report-2014-q2.
Notes 32
17 S ee note 3.
18 I bid.
19 S ee note 2.
20 S ee methodology for our definitions of big box
stores and calculation of available rooftop space.
21 S ee methodology. 24.1 GW of solar photovoltaic
capacity have been installed in the U.S. as of Q3 2015:
SEIA, U.S. Solar Market Insight: U.S. Installs 1.3 GW in Q3, Headed Toward Record-Breaking 2015, archived at web.
archive.org/web/20160201203850/http://www.seia.org/
research-resources/us-solar-market-insight; the average U.S. household consumed 10.908 MWh of electricity an-
nually in 2013: U.S. Energy Information Administration, Frequently Asked Questions: How much electricity does
an American home use?, available at web.archive.org/
web/20150618232948/http://www.eia.gov/tools/faqs/
faq.cfm?id=97&t=3; Walmart uses 28.274 MWh per day
(10,320.01 MWh/yr): Sierra Club, What Is Wal-Mart’s True Environmental Footprint?, downloaded from //web.archive. org/web/20150706053443/http://vault.sierraclub.org/
pressroom/media/201 1/201 1-06-walmart.pdf, 5 July 2015. 22 Se e Methodology.
23 Se e Methodology.
24 T his list excludes grocery retailers. See methodol - ogy for details of solar potential calculation. See footnote 98 for full list of sources for retail footprints.
25 S ee Methodology for details on solar capac -
ity calculations. Also, note that retailers often operate in buildings owned by separate real estate companies.
26 W ill Macht, Urban Land Institute, Greening the Big Blue Box, 26 October 2012.
27 S ee note 3.
28 C apacity and number of locations: See note 3;
15 to 30 percent: Walmart, Renewable Energy, accessed at web.archive.org/web/20150703230251/http://corporate.
walmart.com/global-responsibility/environment-sustain-
ability/energy, 3 July 2015.
29 U .S. Environmental Protection Agency, Green
Power Partnership: Top 30 Retail, 27 April 2015, available at web.archive.org/web/20150703230820/http://www.epa.
gov/greenpower/toplists/top30retail.htm.
30 S olarCity, SolarCity Announces New Solar Power
and Energy Storage Projects with Walmart (press re-
lease), 20 November 2014, available at web.archive.org/ web/20150705223058/http://www.solarcity.com/news-
room/press/solarcity-announces-new-solar-power-and-
energy-storage-projects-walmart.
31 W almart, Walmart Puts the Price of Solar Power on
Rollback: Commits to Doubling On-Site Solar Projects in the United States by 2020 (press release), 9 May 2014, available at web.archive.org/web/20150705212829/http://news.
walmart.com/news-archive/2014/05/09/walmart-puts-
price-of-solar-power-on-rollback.
32 I n January 2016 Walmart announced it would
close 154 stores; however as of July 2015 the retailer
had 5,109 stores nationwide: National Retail Fed-
eration, Top 100 Retailers, accessed at web.archive.org/ web/20150703213447/https://nrf.com/2015/top100-table, 3 July 2015.
33 L indsey Hallock, Frontier Group, Rob Sargent,
Environment America Research & Policy Center, Shining
Rewards: The Value of Rooftop Solar Power for Consumers and Society, Summer 2015.
34 G lobal Carbon Atlas, Emissions, accessed at www.
globalcarbonatlas.org/?q=en/emissions, 22 January 2015. 35 R obert W. Howarth, Cornell University, “A Bridge
to Nowhere: Methane Emissions and the Greenhouse Gas
Footprint of Natural Gas,” Energy Science & Engineering, 22 April 2014, doi: 10.1002/ese3.35.
33 S olar on Superstores
36 B ased on harmonized data for all energy sources
other than natural gas (for which published data were
used) from National Renewable Energy Laboratory, LCA
Harmonization, accessed at www.nrel.gov/analysis/sus-
tain_lcah.html, 15 February 2015.
37 A ssuming solar power offsets fossil fuels, based
on state electricity grids as they were in 2013. See method- ology and U.S. Environmental Protection Agency, Green-
house Gas Equivalencies Calculator, accessed at epa.gov/ cleanenergy/energy-resources/calculator, 19 June 2015.
38 I KEA Foundation, IKEA Group and IKEA Foundation
Commit a Total of EUR 1 Billion for Climate Action, 4 June 2015, available at web.archive.org/web/20150706023444/
http://www.ikeafoundation.org/1-billion-for-climate-
action.
39 W almart, Walmart Marks Fulfillment of Key Global
Responsibility Commitments (press release), accessed at news.walmart.com/news-archive/2015/11/17/walmart-
marks-fulfillment-of-key-global-responsibility-commit-
ments, 17 November 2015.
40 R eal Goods Solar, Real Goods Solar Delivers Solar
Power Systems to 4 Stop & Shop Stores in NY,
41 P . Denholm, National Renewable Energy Labo -
ratory, The Technical Potential of Solar Water Heating to Reduce Fossil Fuel Use and Greenhouse Gas Emissions in the United States, March 2007.
42 I bid.
43 U .S. Environmental Protection Agency, Green-
house Gas Equivalencies Calculator, accessed at epa.gov/ cleanenergy/energy-resources/calculator, 19 June 2015.
44 S ee note 41.
45 T anja Peschel, “New Business Models for Com -
mercial Solar Thermal,” Sun & Wind Energy, 30 June 2015, available at web.archive.org/web/20150709230009/http:// www.sunwindenergy.com/solar-thermal/new-business-
models-commercial-solar-thermal.
46 R ichard Perez, University at Albany, State Univer - sity of New York, Ken Zweibel, George Washington Univer- sity, and Thomas Hoff, Clean Power Research, Solar Power Generation in the US: Too Expensive, or a Bargain?, 2011. 47 M ichael Panfil, “Resiliency+: Distributed Genera - tion and Microgrids Can Keep Lights on During the Next
Storm,” Environmental Defense Fund Energy Exchange, 22
May 2014.
48 A mericans for a Clean Energy Grid, Smart Solar In- verters, August 2014, available at cleanenergytransmission. org/wp-content/uploads/2014/08/Smart-Solar-Inverters.
pdf.
49 W endy Wilson, Travis Leipzig & Bevan Griffiths-
Sattenspiel, River Network, Burning Our Rivers: The Water Footprint of Electricity, April 2012.
50 J ohn Rogers et al., Union of Concerned Scientists, Water-Smart Power: Strengthening the U.S. Electricity System in a Warming World, July 2013.
51 J oe Eaton, “Record Heat, Drought Pose Problems for U.S. Electric Power,” National Geographic News, 17 August 2012. 52 D ana Hull, “Drought Threatens California’s Hydro - electricity Supply, But Solar Makes Up the Gap,” San Jose Mercury News, 1 1 February 2014.
53 A lison Kemper and Roger Martin, “Volatile Fossil
Fuel Prices Make Renewable Energy More Attractive”, The Guardian, 21 March 2013.
54 G eorge L. Nichols, Vermont Energy Investment
Corporation, and Stanley L. Greschner, Grid Alternatives, Successful Solar Incentive Programs Grow Solar Penetration Within Low-Income Communities #203, February 2013.
55 I bid.
56 U .S. Energy Information Administration, “Table 10.
Supply and Disposition of Electricity, 1990 through 2012,” accessed at www.eia.gov/electricity/state/unitedstates/in- dex.cfm, 19 June 2014. Electricity sales: U.S. Energy Informa- tion Administration, State Electricity Profiles: Data for 2012, 1 May 2014, accessed at www.eia.gov/electricity/state.
Notes 34
57 L . Bird et al, National Renewable Energy Labo -
ratory and Regulatory Assistance Project, Regulatory
Considerations Associated with the Expanded Adoption of Distributed Solar, 1 1 November 2013,.
58 U .S. Energy Information Administration, Monthly
Energy Review, “Table 7.2a: Electricity Net Generation:
Total (All Sectors),” June 2015.
59 U nited States Environmental Protection
Agency, Clean Energy, accessed at web.archive.org/
web/20150617201856/http://www.epa.gov/cleanenergy/
energy-and-you/affect/air-emissions.html, 9 February
2015.
60 U .S. Environmental Protection Agency, Sulfur
Dioxide: Health, accessed at www.epa.gov/oaqps001/sul-
furdioxide, 14 June 2013.
61 F abio Caiazzo et al., “Air Pollution and Early
Deaths in the United States. Part I: Quantifying the Impact of Major Sectors in 2005”, Atmospheric Environment, 79:198- 208, 31 May 2013.
62 M . Lippman, “Health Effects of Ozone: A Critical
Review,” Journal of the Air Pollution Control Association, 39:
672-695, 1989; I. Mudway and F. Kelley, “Ozone and the
Lung: A Sensitive Issue,” Molecular Aspects of Medicine, 21:
1-48, 2000; M. Gilmour et al., “Ozone-Enhanced Pulmonary Infection with Streptococcus Zooepidemicus in Mice: The Role of Alveolar Macrophage Function and Capsular Viru- lence Factors,” American Review of Respiratory Disease, 147:
753-760, March 1993.
63 T he Solar Foundation, National Solar Jobs Census
2015, January 2016.
64 I bid.
65 J ohn Rogers and Laura Wisland, Union of Con -
cerned Scientists, Solar Power on the Rise: The Technologies and Policies Behind a Booming Energy Sector, August 2014. 66 A verage commercial rate in Q3 2005 was 9.09
cents; in Q3 2015 it was 10.95 cents.
67 Se e methodology.
68 S outhern California Edison, Costco Eases the
Power Peak with a Solar Solution, accessed at web.archive. org/web/20150625184122/https://www.sce.com/wps/
wcm/connect/6d8dfcc7-10cf-4f5b-8cad-b10b6c8d7d20/
NR719_1007CostcoCSICaseStudy.pdf?MOD=AJPERES, 25
June 2015.
69 J . Neubauer and M. Simpson, NREL, Deployment
of Behind-The-Meter Energy Storage for Demand Charge
Reduction, January 2015.
70 I bid.
71 A nthony Dominguez et al., “Effects of solar
photovoltaic panels on roof heat transfer,” Solar Energy, doi:10.1016/j.solener.2011.06.010, 2011.
72 S ee note 3.
73 U .S. Environmental Protection Agency, Green
Power Partnership: Top 30 Retail, 27 April 2015, available at web.archive.org/web/20160201200850/http://www3.epa.
gov/greenpower/toplists/top30retail.htm.
74 K ohl’s, Kohl’s Department Stores Recognized
with 2014 EPA Sustained Excellence in Green Power Award (press release), available at businesswire.com/news/
home/20141 1 19005140/en/Kohl’s-Department-Stores-
Recognized-2014-EPA-Sustained, 19 November 2014.
75 K ohl’s, Kohl’s Department Stores Activates Its Largest Solar Project at Maryland E-Commerce Distribution Center (press release), available at www.businesswire.com/news/ home/201212180051 12/en/Kohl%E2%80%99s-Department-
Stores-Activates-Largest-Solar-Project, 19 November 2014. 76 S ee note 3.
77 Su npower, Macy’s Goes Solar in 30 Stores, ac-
cessed at web.archive.org/web/20150705225342/http://
us.sunpower.com/commercial-solar/case-studies/macys, 5
July 2015.
78 I bid.
79 I bid.
80 S ee note 3.
35 S olar on Superstores
81 “ Target Commits to Solar Power at 500 Stores,”
Green Retail Decisions, archived at web.archive.org/
web/20160201202306/http://www.greenretaildecisions.
com/news/2015/02/26/target-commits-to-solar-power-at-
500-stores, 26 February 2015.
82 P eyton Boswell and Joe Stofega, “Commercial
Rooftop Success: A Little Ballast and a Lot of Business Sense,” Solar Industry Mag, January 2015.
83 H erman Trabish, “Bringing Bank Money to Solar,”
Greentech Media, 24 January 2013.
84 I bid.
85 U .S. Department of Energy, Commercial Property
Assessed Clean Energy (PACE) Primer, accessed at web.ar- chive.org/web/20150706043227/http://www1.eere.energy.
gov/wip/pdfs/commercial_pace_primer_revised.pdf, 5
July 2015.
86 J ason Coughlin, et al., National Renewable En -
ergy Laboratory, A Guide to Community Shared Solar: Utility, Private, and Nonprofit Project Development, May 2012.
87 M ike Munsell, “Here’s How U.S. Commercial Solar
Can Bounce Back in 2015,” Greentech Media, 1 April 2015, available at web.archive.org/web/20150706042215/http:// www.greentechmedia.com/articles/read/heres-how-u.s.-
commercial-solar-can-bounce-back-in-2015.
88 B arry Friedman et al., NREL, Benchmarking Non-
Hardware Balance-of-System (Soft) Costs for U.S. Photovoltaic Systems, Using a Bottom-Up Approach and Installer Survey – Second Edition, October 2013.
89 S ara Rafalson, “Why Option R Is a Big Deal for
Southern California’s Commercial Solar Market,” SolSys- tems, 20 March 2015.
90 J . Paidipati, et al., National Renewable Energy
Laboratory, Rooftop Photovoltaic Market Penetration Sce- narios, February 2008.
91 N REL provided power density factors for solar
panels at 13.5 percent efficiency, their estimate for 2008, and 18.5 percent efficiency, their projection for 2015.
18.5 percent is closer to solar panel efficiencies today using current technologies: Sunpower, Facts about Solar Technology from SunPower, available at web.archive.org/ web/20150721214056/http://us.sunpower.com/solar-pan-
els-technology/facts.
92 S ee note 90.
93 A nthony Lopez et al., National Renewable Energy
Laboratory, U.S. Renewable Energy Technical Potentials: A GIS-Based Analysis, July 2012.
94 M ore information about NREL ’s capacity factor
calculation can be found in: Paul Denholm and Robert
Margolis, NREL, Supply Curves for Rooftop Solar PV-Generat- ed Electricity for the United States, November 2008.
95 U .S. Energy Information Administration, Electric-
ity Sales, Revenue and Average Price, 2001-2013, available at web.archive.org/web/20150701221341/http://www.eia.
gov/electricity/sales_revenue_price.
96 U .S Energy Information Administration, Electric-
ity, “U. S. electric power industry estimated emissions by state, back to 1990 (EIA-767 and EIA-906)” and “Electricity net generation: electric power sector by state by type of producer by energy source, annual back to 1990 (EIA-906, EIA-920, and EIA-923,” downloaded from web.archive.org/ web/20150514233503/http://www.eia.gov/electricity/data. cfm, 14 May 2015.
97 A verage household energy consumption: See
note 21; Walmart uses 28.274 MWh per day (10,320.01
MWh/yr): Sierra Club, What Is Wal-Mart’s True Environ-
mental Footprint?, downloaded from web.archive.org/
web/20150706053443/http://vault.sierraclub.org/press-
room/media/201 1/201 1-06-walmart.pdf, 5 July 2015.
Notes 36
98 S ee Methodology for calculation of solar po -
tential from retail space; to estimate household power
equivalent, capacity was converted to generation using
capacity factor extrapolated from NREL source cited in
note 93; for average household electricity consumption
nee note 21. Total retail space was found in or estimated based on the following sources: Walmart: 2015 Annual
Report (Walmart U.S. Segment) available at s2.q4cdn.
com/056532643/files/doc_financials/2015/annual/2015-
annual-report.pdf; Costco: 2015 Annual Report available at phx.corporate-ir.net/phoenix.zhtml?c=83830&p=irol-
reportsannual; Home Depot: 2014 Annual Report
available at media.corporate-ir.net/media_files/
IROL/63/63646/2015%20Annual%20Report_Home%20De-
pot.pdf; Target: 2014 Annual Report available at corporate. target.com/_media/TargetCorp/annualreports/2014/pdf/
Target-2014-Annual-Report.pdf?ext=.pdf; Lowe’s Com-
panies: 2014 Annual Report available at phx.corporate-ir. net/phoenix.zhtml?c=95223&p=irol-reportsannual; Best
Buy: 2015 Annual Report available at investors.bestbuy. com/investor-relations/financial-info/annual-reports-
and-proxy-statements/default.aspx; Macy’s: 2014 Annual
Report available at investors.macysinc.com/phoenix.
zhtml?c=84477&p=irol-reportsannual; Sears Holdings
(Sears and KMart): 2014 Annual Report available at sear- sholdings.com/docs/investor/SHC_2014_Form_10-K.pdf;
TJX (Marshall’s and TJMaxx): 2014 Annual Report available at nasdaqomx.mobular.net/nasdaqomx/7/3475/4966/;
Kohl’s: 2014 Annual Report available at www.kohlscor-
poration.com/InvestorRelations/sec-filings.htm; BJ’s
Wholesale Club: 201 1 SEC Filing available at www.sec.
gov/Archives/edgar/data/1037461/000119312511079572/
d10k.htm; Nordstrom: 2014 SEC Filing available at investor. nordstrom.com/phoenix.zhtml?c=93295&p=irol-report-
sannual; Gap (Gap, Banana Republic, Old Navy, Piperlime, Athleta, and Intermix): 2014 SEC Filing available at www. sec.gov/Archives/edgar/data/3991 1/000003991 1 15000101/ fy201410-k.htm; J.C. Penney Co.: 2013 SEC Filing available at ir.jcpenney.com/phoenix.zhtml?c=70528&p=irol-report- sAnnual; Bed Bath & Beyond: 2014 Annual Report available at phx.corporate-ir.net/phoenix.zhtml?c=97860&p=irol-re- portsannual (proportion of Bed Bath & Beyonds located in the U.S. versus Canada and Mexico was not clear in report filing, so estimated that 75% of retail space is located in U.S., in line with similar chains); Menard: average store size not publicly available – total retail space estimated assuming average retail space per store is equal to average store size of Lowes and Home Depot, number of Men-
ard locations in the U.S. is available at web.archive.org/ web/20160201205354/http://menards.com/main/footer/
company-information/about-us/c-3582.htm; Toys “R” Us:
2015 SEC filing available at phx.corporate-ir.net/phoe- nix.zhtml?c=120622&p=irol-sec; Dick’s Sporting Goods:
2013 SEC Filing available at sec.gov/Archives/edgar/
data/1089063/000108906314000046/dks-20140201x10k.
htm; Staples: 2015 SEC Filing available at investor.staples. com/phoenix.zhtml?c=96244&p=irol-sec; Office Depot:
2014 SEC Filing available at investor.officedepot.com/
phoenix.zhtml?c=94746&p=irol-reportsannual; Foot
Locker: 2014 Annual Report available at www.footlocker- inc.com/pdf/2015/pr_2015_fl_2014_Annual_Report_
Including_10-K-Final.pdf; Ascena Retail Group (Lane
Bryant, maurices, dressbarn, Catherines and justice): 2015 SEC Filing available at www.ascenaretail.com/investors. jsp; Burlington Coat Factory: 2015 SEC Filing available at burlingtoninvestors.com/sec-filings/SEC-Filings-Details/ default.aspx?FilingId=10587323; IKEA: total retail space estimated based on average global store size calculated with data available at ikea.com/ms/en_EG/about-the-ikea- group/company-information, assuming 40 Ikea locations
in the U.S. based on nrf.com/2015/top100-table.
99 S ee note 98 for estimates of retail space and
Methodology for calculation details. See note 3 for source of SEIA capacity data.