There are more than 100,000 big-box stores in the U.S., and if solar panels were installed on their roofs, it could meet half of their energy needs, a recent report indicated.
The flat, open roofs of the nation’s big-box stores and shopping centers have almost 7.2 billion square feet of space that would be “perfect locations for solar panels,” the report “Solar on Superstores” by Environmental America Research and Policy Center and the Frontier Group indicates. The researchers used data from the National Renewable Energy Laboratory to calculate the roof space, with NREL estimating that two-thirds of that space is usable.
That space could generate 84.4 terawatt-hours of solar electricity each year, an amount that would power almost 8 million homes. It would also reduce global warming pollution by 52 million metric tons of CO2 annually – equivalent to taking 11.3 million cars off the road.
Walmart has the most rooftop solar space, followed by Target, Home Depot, and Lowe’s. The states with the most emissions reduction potential are Texas, California, Florida, Illinois, Ohio, and Pennsylvania.
Some retailers are already working to put solar installations on store rooftops. The study noted that the Solar Energy Industries Association reported that Apple, Amazon, Walmart, and Target had the most solar installed as of 2019, totaling 1.4 gigawatts of electricity. Walmart’s solar projects have already saved it over $1 million.
The study makes a number of recommendations to boost the usage of store roofs for solar installations. It suggests businesses “set ambitious goals to install solar generation capacity on their facilities and invest the time and resources needed to meet these goals,” set comprehensive environmental goals, and use their political influence to advocate for policy changes.
The study also urges the government to implement solar-friendly policies to encourage companies to take on projects, including expanding tax incentives and credits, enacting financial tools, and streamlining permitting and interconnection processes.
“Almost any large retail building, warehouse, or distribution facility is capable of supporting a solar installation, and most parking lots could be covered by a solar canopy. Big box brands should install solar on as many of their buildings and parking areas as possible, as quickly as possible,” the study urges.