Matt Simon writes that airports have lots of open spaces and big buildings that are never in shadow, which would make them perfect places to locate solar panel arrays. It would be much easier and provide a bigger return than an equal area spread out over residential roofs. For example, Denver International Airport has 53 square miles of usable space, enough to provide up to 30% of its annual energy needs and, on sunny days, all of it.
New research out of Australia shows how massively effective it would be to solarize 21 airports in that country. Researchers scanned satellite images of the airports for open roof space, where solar panels best avoid shadows, and found a total of 2.61 square kilometers, or 1 square mile, of usable area.
For comparison, they also scanned satellite imagery and found 17,000 residential solar panels in the town of Bendigo, just north of Melbourne in southern Australia. The researchers calculated that the airports could potentially produce 10 times the amount of solar energy as those 17,000 residential panels—enough to power 136,000 homes
The associated issue with solar power is the need to store the power to reuse during the time when there is no sunlight. Advances in battery technology are helping to address that.
San Francisco International Airport’s solar panels currently generate 4.6 megawatts, while its peak demand is 55 megawatts. (In contrast to DEN’s wide open spaces, SFO sits on about 8 square miles.) Officials there are currently studying where they might locate more panels to build out a “microgrid,” or a self-sufficient system that would use solar to charge massive batteries. If there’s a blackout, instead of shifting to generators—like SFO currently does—they could switch to backup batteries to electrify essential facilities.
There are some hurdles that need to be overcome with using airports as giant solar farms. They have to be sure that they do not interfere with flights by creating glare for the pilots or disrupt radar and radio communications. But that seems like it should not be a big hurdle.