In most countries solar power is often perceived as synonymous with solar photovoltaic (PV), the classic rooftop panels that convert sunlight to electricity through solar cells. But that could be a misconception, says Environmental Protection, since solar thermal, which gets less attention than PV, actually is more efficient.
Solar thermal is cheaper and more efficient, EP points out. “PV converts 12 per cent of energy into usable electricity at a cost of 25 to 35 cents per kilowatt hour. Solar thermal, which includes solar air and solar water … offers 55 per cent efficiency at 12 to 15 cents per kilowatt hour, and solar air delivers 80 percent at 3 to 9 cents per kilowatt hour”.
If that’s the case, why does PV get more airplay than thermal? Enerconcept Technologies president Christian Vachon says it’s because PV gets most subsidies. “Governments should stop thinking that solar is expensive and needs to be heavily subsidized in order to be sustainable. With PV, we’re putting all our eggs in the longest possible payback basket. Our leaders should instead focus on an energy policy that promotes the lowest-cost energy technology”, he told EP.
Solar thermal electricity can be produced on a large scale as well. Spain recently became home to the world’s first 24/7 solar thermal plant near Seville in the south of the country and it’s expected to produce 110 GW/h per year.
Article by Antonio Pasolini, a Brazilian writer and video art curator based in London, UK. He holds a BA in journalism and an MA in film and television.