This Earth Day, the sun may shine more brightly around the country.
That’s because solar farms, once considered rare, are popping up in the nation’s airports, which have famously high electricity bills.
Over the past two years, solar farms built at the airports of Dallas-Fort Worth, Miami and San Diego – where the cost of building them is lower than private rooftop panels – have helped reduce the airport’s power bill by $1.8 million over a 15-year period, according to Port of San Diego spokesman Mark Stewart.
“Solar farms are really affordable to us,” he said.
Just last month, four solar farms – two at San Francisco International and two at San Jose’s Mineta San Jose International Airport – added more than 10 megawatts of solar capacity to the area’s power grid, enough to power more than 1,500 homes, according to the Silicon Valley Leadership Group, an industry group. It was the second expansion of those plants.
These solar farms can help consumers save money, but in some cases, they’re also helping to make cities a little greener. In Texas, the San Diego County Regional Airport’s site was developed by NRG, which reduced the amount of nitrogen oxide – a greenhouse gas – emissions by 20 percent, according to the airport’s representative, Tim Evans.
Nationally, solar farms are growing rapidly. Each year, there are about 500 new projects under construction, according to the Solar Energy Industries Association. Today, such projects total more than 2,000 megawatts, enough to power about 5 million homes.
When most people think of solar farms, they tend to be attached to massive, expensive buildings, like solar farms inside a Powerplant. But in urban areas, they often hang on the bases of homes or businesses and can be placed on rooftops or in parking lots.
There are rules, however, for putting such farms where they work best. To maximize on-site capacity, airports typically require landowners to sell them all the electricity they can produce. At airports, however, the production costs are particularly low, the Port of San Diego’s Stewart said.
Three years ago, the Port of San Diego partnered with First Solar Inc., a solar company based in California. The two owned and operated a solar farm on the airport’s property. It was added to the airport’s energy portfolio in October 2015. Before, it generated 1.4 megawatts of power, enough to power 150 homes.
Today, its 5 megawatts generate nearly twice as much energy, a rate Stewart said had been achieved despite the extra solar panels used for shading.