To most people, a solar farm or a geothermal plant is simply a power producer. Scientists and engineers see far more potential. They envision offshore wind turbines capturing and storing carbon beneath the sea, and geothermal plants producing essential metals for powering electric vehicles. Electric vehicle batteries, too, can be transformed to power homes, saving their owners money. “In a 2021 study, we showed that covering all 4,000 miles of California’s canals with solar panels would save more than 65 billion gallons of water annually by reducing evaporation. That’s enough to irrigate 50,000 acres of farmland or meet the residential water needs of more than 2 million people,” writes engineering professor Roger Bales of the University of California, Merced. They would also expand renewable energy without taking up farmable land.