All of that solar needs a lot of space. Powering just one megawatt of capacity requires at least five acres, meaning a 200-megawatt project takes up as much space as 550 American football fields. That calculus is one reason China—the world’s biggest solar market—is hosting many projects in remote desert regions. It’s also why the IEA expects rooftop and residential solar to expand faster than farms this year.
It’s also the architect of a 6.5-megawatt canopy project at Caesars Entertainment Casinos in Atlantic City, New Jersey. The project supplies about 6 percent of the energy used by the casino, while also providing shade for the top deck of the parking garage. “You’re close to the demand and it’s a large amount of space,” he says. “The challenge is finding that exact combination.”To dodge land constraints entirely, many countries are experimenting with solar farms that float. While the costs can be high—40 percent more than land farms, according to BloombergNEF—big flat surfaces with constant access to sunlight are compelling.
Floating farms don’t necessarily generate more electricity than those on land, but a study published in Nature Sustainability found that more than 6,000 local power systems around the world could be entirely self-sufficient with floating farms.
“It’s dead space and can’t be built on otherwise, you might as well build a solar farm,” says Jones at DSD, which opened a 4.3-megawatt solar farm on a landfill last year in Bethel, New York. More than half of the power generated supplies local residents and businesses.