Eco Factor: Solar panels that generate electricity from heat and light.
Until now excessive heat has been a limiting factor for solar panel efficiency, which decreases as the incident heat increases. Researchers at Stanford University have come up with a plan that will make it possible for solar panels to generate electricity from both sunlight and heat. The process, called “Photon Enhanced Thermionic Emission,” or PETE, combines light and heat of solar radiation to produce electric current.
Unlike current solar panel technology, which becomes less efficient as the temperature rises, the new process become more efficient with the rise in temperature. The team figured out a way to coat a piece of semiconducting material with a thin layer of metal cesium, which enables the panels to absorb both light and heat to generate electricity.
The research team claims that while most silicon solar cells become inert by the time the temperature reaches 100 degrees Celsius, the PETE device doesn’t hit peak efficiency until the temperature is well over 200 degrees Celsius. Since PETE devices will work well at temperatures well in excess of what a rooftop installation will ever reach, the devices could be a valued addition to solar concentrators such as parabolic dishes, which get as hot as 800 degrees Celsius.
As light will come, it will first hit the PETE device, which will generate electricity from both incident light and heat. The waste heat will then be transferred to the existing thermal conversion systems to even better the efficiency of the entire setup.
Via: Gizmag
