As part of a project developed by San Francisco area start-up WaterFX, a giant solar receiver in Firebaugh, CA, rotates to track the sun and capture its energy. The 377-foot array, however, does not generate electricity, but instead creates heat used to desalinate water. The goal is to tap the abundant, if contaminated, resource in this parched region: the billions of gallons of water that lie just below the surface.
The water is tainted with toxic levels of salt, selenium and other heavy metals that wash down from the nearby Panoche foothills, and is so polluted that it must be constantly drained to keep it from poisoning crops. This, coupled with the record-breaking drought that California is facing means that irrigation costs are going to double or triple as farms are forced to buy water on the spot market.
"Food prices are going to go up, absolutely", said Dennis Falaschi, manager of the Panoche Water District. "This year, farmers in the Panoche district will receive no water. Last year, they received only 20 percent of their allocation", Mr. Falaschi said. In 2012, the allocation was 40 percent. Farmers elsewhere who rely on the State Water Project to irrigate 750,000 acres of farmland will also receive no water in 2014.
The costs of LEDs have come WAY down, their efficiencies have gone WAY UP (hovering at 50% efficiency power in/light out) and the feasibility of solar powering the entire thing is better than good. That much has been solved.
Pushing the environmental effects off one tier may not be necessary. The desalination plant itself could use the harvested salts and make fertilizer from them (after a bit of centrifugal processing to remove many of the heavier metals) and have another useful product. Look up SEA-90 to see what I mean.