Mounting evidence suggests the western United States is now in its worst megadrought in at least 1,200 years. Groundwater supplies are being overpumped in many places, and the dryness, wildfires and shrinking water supplies are making climate changepersonal for millions of people.
As an engineer, I have been working with colleagues on a way to both protect water supplies and boost renewable energy to protect the climate.
We call it the solar-canal solution, and it’s about to be tested in California.
About 4,000 miles of canals transport water to some 35 million Californians and 5.7 million acres of farmland across the state. As we explained in a 2021 study, covering these canals with solar panels would reduce evaporation of precious water – one of California’s most critical resources – and help meet the state’s renewable energy goals, while also saving money.
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About our team
The first prototypes in the U.S. for both wide-span and narrow-span canals are now in development in California’s Central Valley. Researchers at the University of California, Merced, are involved in the project, and we will be trying to determine how this can become a large-scale solution.
Conserving water and land
California is prone to drought, and water is a constant concern. Now, the changing climate is bringing hotter, drier weather.
Severe droughts over the past 10 to 30 years dried up wells, caused officials to implement water restrictions and fueled massive wildfires.
At the same time, California has ambitious conservation goals. The state has a mandate to reduce groundwater pumping while maintaining reliable supplies to farms, cities, wildlife and ecosystems. As part of a broad climate change initiative, in October 2020 Gov. Gavin Newsom directed the California Natural Resources Agency to spearhead efforts to conserve 30% of land and coastal waters by 2030.
Most of California’s rain and snow falls north of Sacramento during the winter, while 80% of its water use occurs in Southern California, mostly in summer. That’s why canals snake across the state – it’s the largest such system in the world. We estimate that about 1%-2% of the water they carry is lost to evaporation under the hot California sun.
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. By concentrating solar installations on land that is already being used, instead of building them on undeveloped land, this approach would help California meet its sustainable management goals for both water and land resources.
FOR MORE INFORMATION: https://theconversation.com/first-solar-canal-project-is-a-win-for-water-energy-air-and-climate-in-california-177433
GET WET! 