Researchers at the Laboratory for Organic Electronics at Linköping Universitet, Sweden, have created a supercondenser that can be charged by the sun. It contains no expensive or hazardous materials, has patents pending, and it should be fully possible to manufacture it on an industrial scale.
In the future we could have a completely new type of energy storage, charged by heat energy -- for example during the day when the sun shines, or by waste heat from an industrial process. The heat is converted to electricity, which can be stored until it is needed. The results have recently been published in the journal Energy Environmental Science.
Simply put, a supercondenser is energy storage: a type of battery that consists of an electrolyte of charged particles -- ions -- between two electrodes. The charge is stored next to the electrodes, most often in carbon nanotubes. One of the physical phenomena that the researchers make use of here is that if a supercapacitor is exposed to a temperature gradient -- that is, one end is warm and the other cold -- the ions rush towards the cold side and an electric current arises.