A team led by Jim Harris and Thomas Jaramillo, an associate professor of chemical engineering and of photon science, has made a significant improvement to the efficiency of solar energy. In work published in Nature Communications, they were able to capture and store 30 percent of the energy captured from sunlight into stored hydrogen, beating the prior record of 24.4 percent.
Solar energy has the potential to provide abundant power, but only if scientists solve two key issues: storing the energy for use at all hours, particularly at night, and making the technology more cost effective. The interdisciplinary team has made significant strides toward solving the storage issue, demonstrating the most efficient means yet of storing electricity captured from sunlight in the form of chemical bonds. If the team can find a way of lowering the cost of their technology, they say it would be a huge step toward making solar power a viable alternative to current, more polluting energy sources.
The basic science behind the team's approach is well understood: Use the electricity captured from sunlight to split water molecules into hydrogen and oxygen gas. That stored energy can be recovered later in different ways: by recombining the hydrogen and oxygen into water to release electricity again, or by burning the hydrogen gas in an internal combustion engine, similar to those running on petroleum products today.
"It took specialists in different fields to do what none of us could have done alone," Harris said. "That's one of the lessons of this result: There is no single fix. How everything links together is the key."
Jim Harris is the James and Elenor Chesebrough Professor in the School of Engineering, professor, by courtesy, of applied physics and of materials science and engineering, a member of Stanford Bio-X and of the Stanford Neurosciences Institute, and an affiliate of the Precourt Institute for Energy and the Stanford Woods Institute for the Environment. Jamarillo is also an affiliate of the Precourt Institute for Energy.
This article is adapted from the Stanford Report. Read full article.