Big Box Stores Offer Big Opportunities for Expanding Rooftop Solar

A recent study by two organizations, Environment America Research and Policy Center and the Frontier Group, researched rooftop potential on big box stores to host solar installations throughout the country. Their findings show that rooftop solar on commercial big box store roofs are a substantial opportunity to boost clean energy production.

With over 100,000 big box stores nationwide, accounting for over 7 billion square feet of roof space, the potential to generate clean energy is huge. If all of that roof space was covered with solar panels, it could produce over 84 terawatt-hours of electricity a year. That is comparable to the electricity usage of nearly 8 million homes. Installing rooftop solar would cover half of the electricity demand for most of these stores.

The report, Solar on Superstores: Big Roofs, Big Potential for Renewable Energy by The Frontier Group found that since most of the electricity generated would be used by the stores themselves, it would reduce demand for electricity from the grid and utility-scale generation by a similar amount, not to mention savings from losses in the transmission and distribution system.

Furthermore, retail superstore rooftop solar systems could be linked together with other dispatchable generation assets as part of a larger community-based microgrid. When combined with a build-out in local storage capacity would improve the resiliency of the local electrical system. Most retail superstores also have large parking lots that could host solar canopies and EV charging infrastructure, further expanding their benefits.

Commercial-scale rooftops would reduce the need to develop larger utility-scale systems and the associated transmission investments needed on an increasingly congested grid.

Big box stores account for 4.5 percent of total electricity demand, so installing rooftop solar on all of them would reduce demand from the grid by over 2 percent.

This study didn’t even consider the impact of deploying solar on warehouses and distribution centers, which provide a substantial amount of roof space. 

To accelerate deployment of rooftop solar on big box stores, the report makes several recommendations, including extending tax credits for commercial-scale solar systems, preserving policies like net-metering that fairly compensate the owners for times when production from these systems exceeds the consumption of the building, permitting third-party ownership through arrangements like power-purchase agreements (PPAs) and leases, allowing PACE financing, and simplifying the permitting process.

Overall, commercial-scale solar systems on big box stores are a tremendous opportunity to accelerate the deployment of renewable generation, reduce demand from the grid and centralized generation, and provide resilience to those stores and surrounding areas.