Solar Canals Could Generate Energy While Saving Water

Solar Canals Could Generate Energy While Saving Water

A new climate solution is being pioneered in California using the existing irrigation canals that run throughout the state. According to researchers, the canals could (and should) be covered with solar panels to harness sunshine for renewable energy. The move would also prevent evaporation, which costs the state billions of gallons of water.

California’s Department of Water Resources gave a $20 million grant to a team from the University of California, Merced and Santa Cruz to install 8,500 feet of solar panels over canals in the San Joaquin valley. These should generate about 5 megawatts (MW) and be functional in 2023.

23 ABC: California program covering canals with solar panels may conserve water, generate more power, March 15, 2022.

Why This Matters

The West has been in a prolonged megadrought over the last 22 years. Water sources throughout California are rapidly depleting, and the state is looking for ways to cut its water usage. Reusing treated wastewater and collecting runoff from rain could reduce California’s water consumption by 30% or more. Solar canals could also help California save water by preventing evaporation.

Solar canals could help the US meet its climate goals by giving panels a place to exist that doesn’t reduce farmland or wildlife habitats. The Biden Administration aims to scale up solar to supply 40% of energy generation in the nation by 2035. But this level of expansion may conflict with the government’s plan to conserve 30% of US land and water by 2030. Solar canals could provide an answer to these concerns.

CNBC: Severe drought in Southwest threatens water and energy security, April 27, 2022.

VICE: 40 Million People Rely on the Colorado River, and Now It's Drying Up, August 14, 2021.

Pacific Institute: Briefing: The Untapped Potential of California's Urban Water Supply, March 30, 2022.

Potential Pitfalls

A potential problem with solar canals is that the panels could make it harder for utilities to maintain. Still, researchers argue that the panels may prevent maintenance needs because they would provide shades for the canal, reducing algal and weed growth.

Another issue is that solar canals may not be cost-effective. The mounting of panels over canals is more expensive than mounting them on the ground. Depending on how they’re installed, the total average project could cost up to around $2.02 per watt, compared with $1.66 per watt for ground-mounted panels. That said, these estimates do not consider the price of the land, which could make the price per watt of ground-mounted panels more expensive.

The Tesla Domain: Why Covering Canals With Solar Panels Is A Power Move, March 27, 2022.

CBS: Western drought likely to get worse and expand, climate researchers says, March 26, 2022.

CBS: California Falls Behind Water Conservation Goal, March 16, 2022.