If all of the nation's Targets, Walmarts, Lowes, Sam's Clubs, Hobby Lobbys, and Dirt Cheaps installed rooftop solar, they could generate enough power to meet the energy needs of homeowners in almost any major metropolitan city.
That's the word from a recent report by the research group Environment America. By analyzing the potential solar capacity available on the more than 100,000 "big box" stores, malls, supercenters, and outlets, the group determined that there's nearly 7.2 billion square feet of unused rooftop space.
“Rooftop solar is the best electricity source for the moment we’re in. It produces inexpensive clean energy that can be used where it’s generated,” said Susan Rakov, chair of Environment America Research & Policy Center’s clean energy program. “If we want a clean energy future, we should be deploying rooftop solar everywhere we can. Big-box store rooftops are right in the middle of most American communities, and they’re big, flat and panel-ready.”
Turning that into solar fields could generate 84.4 Terawatt hours of electricity -- enough to power roughly 8 million US homes or 30,400 Walmarts.
It's the equivalent of taking over 11.3 million passenger cars and trucks off the road and would reduce greenhouse gas emissions by more than 52 million metric tons. It'd also replace about half of the annual electricity usage of these stores and shopping centers.
Walmart, Target and Amazon are already working to instal more rooftop solar on their stores and fulfillment centers. Those three companies (along with Apple) installed 1.4 gigawatts of solar in 2019. More than 11 percent of the total commercial installed capacity.
Walmart's even saving money from the installations. America's second biggest retailer costs by $1 million and covered one-third of its energy needs with solar, according to the report.
“The potential for Walmart to be a corporate leader on rooftop solar really stands out,” said Wade Wilson, an Environment America Research & Policy Center associate who leads the organization’s Solar on Superstores campaign, in a statement. “If Walmart rises to the opportunity, that will set a standard for other big-box stores to dedicate their rooftops to solar too. And the more solar on rooftops, the more potential solar in our future, as costs keep coming down and adoption goes up.”