In France, solar panels will blanket parking lots

French parking could soon generate as much electricity as 10 nuclear power plants.

France recently passed a law requiring canopies of solar panels to be built atop all substantial lots in the country. The plan makes France a world leader in efforts to cover as many surfaces as possible with solar panels — a step advocates say will be crucial in broader plans to phase out fossil fuels in the coming years.

The expansion could add as much as 8% to France’s current electrical capacity.

As the cost of solar panels continues to drop, they are an increasingly competitive source of energy both for individual households and bigger consumers. But one big challenge is finding enough space for them to generate electricity in bulk.

That’s why policymakers have parking lots in their sights: They are big, unbeautiful and covering them with solar panels doesn’t take away from anything else.

No land-use disputes

One challenge of increasing solar power coverage in a densely populated country such as France is finding ways that don’t compete for land use, said Arnaud Schwartz, the president of France Nature Environment, an umbrella group of French environmentalist organizations.

Taking away agricultural land or open fields and giving it over to solar farms is unattractive but covering parking lots “harms biodiversity a lot less,” he said.

“We live already in parts of the world where it’s pretty dense,” he said. “Human beings are everywhere.”

The plan to require solar-panel-covered parking lots is part of a bigger piece of legislation French President Emmanuel Macron has made a centerpiece of his climate efforts. It will require all parking lots larger than about 16,000 square feet — able to hold roughly 50 American-sized cars — to build raised solar-panel canopies covering at least half of the surface of the parking lot.

‘Least costly way’

“We’ve known for a while that solar energy is the least costly way of generating renewable electricity. In most cases, we can outcompete fossil fuels,” said Joshua Pearce, an engineering professor at the University of Western Ontario in Canada, who has studied the possibility of installing solar panels on the roofs and parking lots of Walmart stores in the U.S.

Those alone would be able to generate about 11 gigawatts of electricity, he estimated, about the high end of the French effort.

Backers expect that when the sun is shining, the panels should be able to generate enough power for the businesses served by the parking lot, and at times for the community surrounding them. One natural use of the electricity from parking lots, advocates say, is for charging electric vehicles, a measure that would avoid the loss of electricity that occurs when it is sent over long distances.

In France, the new law will go into effect in July, and owners of parking lots will have between three and five years to comply.