Solar Canals: A Great Idea with a Health Caveat

"Solar canals" in India

The benefits sound compelling. Putting solar panels over California's aqueducts will reduce evaporation and generate green energy.

The California Department of Water Resources is funding the $20 million pilot program with the intention of learning where solar panels might be viable along the state’s 4,000 miles of canals and aqueducts...

The [UC Merced / UC Santa Cruz] study detailed other benefits, too. Vast tracts of pricey new land wouldn’t be needed to generate solar energy, minimizing debate over the conversion of farmland or pristine desert for throngs of arrays. The solar panels on the canals also would operate more efficiently because the water would keep them cool.

A caveat from history: to help the environment California tends to go all-in on solutions that are not only costly but end up creating environmental damage worse than the original problem.

Case in point: MTBE. California imposed stricter requirements for oxygenated gasoline than set forth in the 1990 Federal Clean Air Act. Refiners added MTBE (methyl tertiary-butyl ether) to gasoline, which was found to be highly toxic when it leaked from tanks into the water supply. IMHO, most people would rather take their chances with smog than drink water that may have been poisoned.

Now back to the subject at hand. Solar panels contain toxic materials, e.g., lead and cadmium, that make them difficult to dispose of properly. If California covers its 4,000 miles of canals with solar arrays, surely there will be some leakage, if not breakage that could jeopardize the water supply.

I just hope that California tests the concept thoroughly before it goes big.