The future’s getting brighter for solar power. Researchers from CU Boulder have created a low-cost solar cell with one of the highest power-conversion efficiencies to date, by layering cells and using a unique combination of elements.
“We took a product that is responsible for a $30 billion a year industry and made it 30% better,” said Michael McGehee, a professor in the Department of Chemical and Biological Engineering and co-author of a paper, to be published tomorrow in Science, which describes the technology. “That’s a big deal.”
The researchers took a perovskite solar cell, a crystal structure that's designed to harvest higher energy photons, and layered it on top of a silicon solar cell, which captures more photons in the infrared part of the spectrum – which is made up of radiant energy that we cannot see, but we can feel as heat. Combined, the perovskite raises a 21% silicon solar cell up to an efficiency of 27% – increasing it by a third.
For years, silicon solar cells have been the standard in the solar power industry. But current silicon-based cells only convert 18% to 21% of the sun’s energy into usable electricity on average, and they max out at about 26.6%.
Read more at University of Colorado at Boulder
Image: Perovskite/silicon tandem solar cells are contenders for the next-generation photovoltaic technology, with the potential to deliver module efficiency gains at minimal cost. (Credit: Dennis Schroeder / NREL)