Researchers from MIT have fotovolta lwa of cells are designed to function without visible light. The cells convert heat into radiation with a different wavelength that can be used to electrical energy.
The principle that the employees of the Massachusetts Institute of Technology, or MIT, for their photovoltaic cells, is not new, but the implementation would be in accordance with the researchers to get a higher return lead. The tpv cells make use of heat that is converted into infrared radiation, and radiation with a shorter wavelength. Just as in normal pv cells is the radiation used to release electrons and thus to produce electricity.
The conversion of infrared radiation to electricity requires semiconductors with a low band gap, but not all of the infrared energy can be used. The MIT researchers, however, have a material on the basis of tungsten has been developed that heat to infrared radiation with a specific wavelength turnover: that makes the conversion more efficient. With the help of nanostructures on the surface of the infrared radiation were applied, they could be the produced wavelengths of light, precisely tuning the band gap of the pv cells.
The source of heat energy to the tungsten-transmitter must deliver, can range from a radio-active isotope during decay heat supplies, to a butaanbrander. The latter heat source is a button cell used with a microreactor in which butane or propane is burned. This micro-tpv generator can be three times the energy of a evenzware lithium-ion battery can deliver and still has room for improvement. The “charging” requires the plugging in of a new fuel cartridge. A version with a radio-isotope as a source of heat would, according to the researchers, thirty years can go without refueling.
