A team of scientists has invented a new type of solar cell that converts both the sun's heat and light into electricity, potentially giving a boost to the efficiency of solar energy harvesting devices.
The cell combines a photovoltaic process that turns light into electricity with another that converts heat; combined, they beat the current record for solar energy efficiency, as well as the theoretical efficiency limit of a cell of this design.
The most popular type of solar generator in use today is the photovoltaic cell. Photovoltaic cells operate by taking in solar photons of certain energies and using them to excite electrons into racing to conductors, creating current. While photovoltaic cells have been an important step towards harnessing the sun’s energy, they are fairly inefficient and leave a lot of room for improvement.
The average cell can harvest only about 20 percent of the solar energy that lands on it, and the fanciest of photovoltaic cells can’t capture much more than 40 percent. This isn’t the fault of the sun, as there is a phenomenal amount of energy beating down on the earth all the time. That leaves a lot of photons ripe for plucking.
For more on this article: http://arstechnica.com/science/news/2010/08/new-solar-cell-uses-heat-to-beat-theoretical-limits.ars
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