New solar energy tech promises to double efficiency
updated 06:55 pm EDT, Mon August 2, 2010
System utilizes heat and light for conversion
Engineers at Stanford University are working on new technology that aims to double the efficiency of existing solar energy systems. Researchers are testing a conversion method, "photon enhanced thermionic emission," that thrives in higher temperatures, overcoming a drawback of traditional photovoltaic technology that becomes less efficient as temperatures rise.
"The key to our thermal conversion process is that it utilizes both the light and the heat at the same time," said Assistant Professor Nick Melosh. "The higher temperature that you go, the more energy you have to convert."
The research group found that a cesium coating on a piece of semiconducting material allows the system to take advantage of heat and light. The system works best at temperatures in excess of 200ºC, however, making it more suitable candidate for solar concentrators rather than small-scale solar panels.
Melosh suggests the technology is viewed as a potential add-on to existing systems, reducing the costs associated with deploying new parabolic dishes and thermal conversion devices. The research group expects the actual efficiency of production systems to reach 50 to 60 percent, a significant increase over traditional solar cells. [via Nature]
