What California is learning from solar panels built over irrigation canals
Points and comments are a snapshot, not live.
Solar panels over California's irrigation canals cut evaporation and speed clean energy permitting.
California's 4,000 miles of open canals lose water to evaporation, a problem worsened by climate change. Project Nexus, a pilot by Solar Aquagrid and Turlock Irrigation District, covers canal sections with solar panels to generate power and shade water. UC Davis research estimates state water supply could shrink 25% by 2050. Building on developed canal land takes 110 days for permits vs. 621 days on undeveloped land. Shading reduces algae and weed growth, improving water quality and cutting maintenance. Challenges include maintenance access and varying canal designs; a final report is due later this year.
What commenters are saying
Commenters question the cost-effectiveness of covering canals with solar panels versus building panels in a field with a cheap shade structure. They argue the steel supports are expensive, panels act as wind sails, and the approach uses more copper for wiring. The strongest counterpoint is that California's permitting delays make building on developed land far faster-110 vs. 621 days. Some suggest pipes as an alternative, noting costs like $16 billion for 45 miles. Others note that the UK uses floating solar on reservoirs, a lower-profile option.