Many consumers would like to switch to solar power but can’t. It could be their homes have too much shade or their roofs can’t accommodate solar panels, or perhaps they live in a condominium or apartment building.

Enter so-called community or shared solar, which allows people to buy solar power from centrally owned arrays. The power is delivered by the local utility, and customers get credits on their monthly bills for any power the project sells back to the grid.

Although a relatively small business now, community solar is growing and could account for as much as half of the small-scale solar-panel market by 2020, according to an April forecast by the Energy Department’s National Renewable Energy Laboratory in Golden, Colo. That would create a hefty new solar market in between individually owned rooftop arrays and large utility-scale projects.

“There’s a lot of potential [for community solar], particularly with the cost of solar dropping every year and programs being put in place to make things easier and more affordable,” says David Feldman, an analyst at the National Renewable Energy Lab and an author of the report.

Different approaches

The U.S. home solar-power market has grown rapidly in recent years, thanks to falling panel prices and government subsidies. Homeowners nationwide installed 918 megawatts of panels during the first half of this year, nearly quadruple the amount installed in all of 2010, according to GTM Research and the Solar Energy Industries Association. By the middle of 2015, there were about 4,400 megawatts of home rooftop solar panels installed in the U.S., according to GTM, compared with just 81 megawatts for community solar projects.