Suzanne's Mom's Blog

Photo: Imagine China via AP Images.
A solar-covered parking lot at the plant of Anhui Quanchai Engine Co., Ltd. in Chuzhou, China.

We have to keep a close watch on our innovations, even the ones we think are good. Take solar. Sometimes you read about aggressive solar companies decimating wooded lots to build an array. What? Trees are even better than solar at fighting global warming.

Let’s consider places where solar doesn’t harm anything. How about over a parking lot?

Richard Conniff writes at YaleEnvironment 360, “Fly into Orlando, Florida, and you may notice a 22-acre solar power array in the shape of Mickey Mouse’s head in a field just west of Disney World. Nearby, Disney also has a 270-acre solar farm of conventional design on former orchard and forest land. Park your car in any of Disney’s 32,000 parking spaces, on the other hand, and you won’t see a canopy overhead generating solar power (or providing shade) — not even if you snag one of the preferred spaces for which visitors pay up to $50 a day.

“This is how it typically goes with solar arrays: We build them on open space rather than in developed areas. That is, they overwhelmingly occupy croplands, arid lands, and grasslands, not rooftops or parking lots, according to a global inventory published last month in Nature. In the United States, for instance, roughly 51 percent of utility-scale solar facilities are in deserts; 33 percent are on croplands; and 10 percent are in grasslands and forests. Just 2.5 percent of U.S. solar power comes from urban areas.

“But that doesn’t necessarily make it smarter. Undeveloped land is a rapidly dwindling resource, and what’s left is under pressure to deliver a host of other services we require from the natural world — growing food, sheltering wildlife, storing and purifying water, preventing erosion, and sequestering carbon, among others. And that pressure is rapidly intensifying. By 2050, in one plausible scenario from the National Renewable Energy Laboratory (NREL), supplying solar power for all our electrical needs could require ground-based solar on 0.5 percent of the total land area of the United States … 10.3 million acres.

“Because it is more efficient to generate power close to customers, some states could end up with as much as five percent of their total land area — and 6.5 percent in tiny Rhode Island — under ground-based solar arrays, according to the NREL study. If we also ask solar power to run the nation’s entire automotive fleet, says Margolis, that adds another 5 million acres. It’s still less than half the 31 million acres of cropland eaten up in 2019 to grow corn for ethanol, a notoriously inefficient climate change remedy.

“The argument for doing it this way can seem compelling: It is cheaper to build on undeveloped land than on rooftops or in parking lots. And building alternative power sources fast and cheap is critical in the race to replace fossil fuels and avert catastrophic climate change. It’s also easier to manage a few big solar farms in an open landscape than a thousand small ones scattered across urban areas.

Despite the green image, putting solar facilities on undeveloped land is often not much better than putting subdivisions there.

“Developers tend to bulldoze sites, ‘removing all of the above-ground vegetation,’ says Rebecca Hernandez, an ecologist at the University of California at Davis. That’s bad for insects and the birds that feed on them. In the Southwest deserts where most U.S. solar farms now get built, the losses can also include ‘1,000-year-old creosote shrubs, and 100-year-old yuccas,’ or worse. The proposed 530-megawatt Aratina Solar Project around Boron, California, for instance, would destroy almost 4,300 western Joshua trees, a species imperiled, ironically, by development and climate change. … In California, endangered desert tortoises end up being translocated, with unknown results, says Hernandez. …

“The appeal of parking lots and rooftops, by contrast, is that they are abundant, close to customers, largely untapped for solar power generation, and on land that’s already been stripped of much of its biological value.

“A typical Walmart supercenter, for instance, has a five-acre parking lot, and it’s a wasteland, especially if you have to sweat your way across it under an asphalt-bubbling sun. Put a canopy over it, though, and it could support a three-megawatt solar array, according to a recent study co-authored by Joshua Pearce of Western University in Ontario.

“In addition to providing power to the store, the neighboring community, or the cars sheltered underneath, says Pearce, the canopy would shade customers — and keep them shopping longer, as their car batteries top up. If Walmart did that at all 3,571 of its U.S. super centers, the total capacity would be 11.1 gigawatts of solar power — roughly equivalent to a dozen large coal-fired power plants. Taking account of the part-time nature of solar power, Pearce figures that would be enough to permanently shut down four of those power plants.

“And yet solar canopies are barely beginning to show up in this country’s endless acreage of parking lots. The Washington, D.C., Metro transit system, for instance, has just contracted to build its first solar canopies at four of its rail station parking lots, with a projected capacity of 12.8 megawatts. 

“New York’s John F. Kennedy International Airport is now building its first, a 12.3 megawatt canopy costing $56 million. Evansville (Indiana) Regional Airport, however, already has two, covering 368 parking spaces, at a cost of $6.5 million. According to a spokesperson, the solar canopy earned a $310,000 profit in its first year of operation, based on premium pricing of those spaces and the sale of power at wholesale rates to the local utility.

“Rutgers University built one of the largest solar parking facilities in the country at its Piscataway, New Jersey campus, with a 32-acre footprint, an 8-megawatt output, and a business plan that the campus energy conservation manager called ‘pretty much cash-positive from the get-go.’ ”

Lots more info at YaleEnvironment360, here.