In an old interview, the well-known astronomer Neil DeGrasse Tyson jokingly said that ours are already flying cars, since tunnels and overpasses allow them to access the third dimension. Following this reasoning, "flying solar panels" were also born in India and California. Yes: photovoltaic systems "suspended" above irrigation canals.
It's a brilliant way for me to reduce two key factors: habitat loss due to the space usually required by solar panels and evaporation from irrigation canals. Yes, since the shade provided by the panels protects the water in the canals from the evaporative heat of the sun.
Solar on irrigation canals: born in India, arrives in California
With the largest network of irrigation canals in the world and approximately 290 days of sunshine per year, California is uniquely positioned to take advantage of this emerging innovation. The University of Santa Cruz (UCSC) is studying this method as a possible solar energy generator that would save as much as 234 BILLION liters of water per year (63,5 billion gallons). A gigantic change for a state that is sometimes forced to ration water, and which regularly suffers from drought.
However, the history of photovoltaics on the canals starts in the Indian state of Gujarat in 2014. There, a 750-meter pilot project led to the creation & of an entire solar plant on canals in the Vadodara district, and another of 100 megawatts off the Narmada River.
Indian researchers were the first to discover that the water under solar panels runs colder and leads to an average increase in efficiency of between 2 and 5%.
Projections on the “Golden State”
Brandi McKuin and his colleagues at UCSC modeled the pros and cons of solar coverage of the more than 6.000 kilometers of canals in California. They took the mission very seriously, “testing” three separate techniques for measuring water loss in different areas through evaporation, to figure out which construction method would be the most efficient on a large scale.
Their results published on Nature Sustainability they shape a very bright future.
As mentioned, if crossed by solar panels the canals in California would save billions of liters of water annually. Savings that also reduce land costs, maintenance of aquatic plants and an electricity surplus. The most efficient method tested? Construction with steel cables.
That's not all: Diesel-powered water pumps are now used to drive the flow of canals. They would be replaced by generators powered by solar energy. Removing soil from the panels ultimately means returning it to native fauna, or to sustainable farming to improve local economies and food supply.