Solar photovoltaic is currently the most expensive form of electricity available ... which is weird, right? I mean, the fuel is free and the intermediate technology is made out of, essentially, sand. So what's the deal?
In this article for National Geographic News, I probe the details to try and understand what makes solar power so spendy most places—and why it's actually already a reasonably-priced option in others.
So why is solar so expensive?
Converting light into electricity with no moving parts is a profoundly different enterprise than turning a turbine to make power--the technology that is at work in coal, natural gas, nuclear, hydropower plants and, most visibly to the public, at wind farms.
"Wind power is the same technology as it's been for 1,000 years," said Tom Meyer, a professor of chemistry at the University of North Carolina at Chapel Hill. "There's nothing to invent. It just needs to be improved." The makers of wind turbines have made huge cost reductions in recent decades with relatively small tweaks to an otherwise familiar system.
That's not yet true for solar, experts say. Most solar cells are made from silicon--the same semiconductor material that is at the heart of computers. The cells are expensive to produce because it takes a great deal of energy to purify the silicon. And, while the computer industry has made enormous strides in making cheaper silicon devices, those advancements don't translate to the solar industry.
National Geographic News: Shining a Light on the Cost of Solar Energy
Maggie Koerth-Baker is the science editor at BoingBoing.net. She writes a monthly column for The New York Times Magazine and is the author of Before the Lights Go Out, a book about electricity, infrastructure, and the future of energy. You can find Maggie on Twitter and Facebook.