California Solar Project Conserves Water

Researchers in California’s Central Valley demonstrated that covering irrigation canals with solar panels reduces water evaporation by up to 70% and inhibits aquatic weed and algae growth by as much as 85%. The $20 million Project Nexus, a collaboration between the University of California Merced, the Turlock Irrigation District, and Solar AquaGrid, installed solar panel coverings over two canals south of Modesto.

These panels generate 1.6 megawatts of power and span an area equivalent to one and a half football fields. The project initially focused on energy production but revealed substantial water conservation and maintenance benefits.

A 2021 UC Merced study estimated covering all major open canals could generate 13 gigawatts of capacity, half of what California needs to meet its 2030 renewable energy goals, and save 63 billion gallons of water annually. However, researchers caution that widespread implementation faces challenges due to varying canal conditions and higher construction costs than traditional solar farms. The Turlock Irrigation District will use an upcoming UC Merced report to decide on further investment, while the California Department of Water Resources evaluates the technology for its State Water Project.