How do they differ from Photovoltaic Cells?
Both Thermophotovoltaic and Photovoltaic cells work in basically the same way, the exception being that instead of the light hitting the cells and creating an electric field, as in Photovoltaic, the Thermophotovoltaic cell uses a semiconductor designed for longer wavelengths for non-visible light (infrared) emitted by any hot object. The use of these cells provides the potential for a cleaner process of energy generation for commercial and industrial applications, considerably preferable to turbines or conventional generators.
How can Thermophotovoltaics be used?
The use of TPV cells, provide a low maintenance, highly efficient system particularly suited to industrial processes. Because the cells can utilise the energy generated, not only from direct sunlight, but from any other heat source, they could be used to provide electricity from the heat lost during the manufacturing of glass or steel, making the operation, in effect, self-generating. TPV cells could also be used to power generators or charge batteries in a range of commercial, industrial or domestic situations. Some believe that CPV cells could reduce waste and enhance the efficiency of domestic heating systems; having the ability to combine the generation of electricity with hot water production.
Is the Technology Available?
Although the principles behind the installation of TPV cells for general use are sound, the capabilities that would be needed to install a full system are complex and would, potentially, be very expensive. Because of this, no suitable application has yet been found, either in an industrial, commercial or in a domestic location.
This situation could, however, be about to change thanks to the research and development carried out by the Belgian based Interuniversity Microelectronics Centre. IMEC have a wealth of knowledge garnered from their 25 years in the pioneering of Photovoltaic technology and manufacture, and have facilities in Holland, Taiwan, China, Japan and the USA. They have developed an innovative process which can re-fabricate a standard Germanium-based TPV, resulting in the production of a cell with a greatly enhanced waste-heat to electricity conversion efficiency. If their technology could be applied to a standardized production process, it could revolutionise the manufacture of TPV cells, delivering a high performance product at a much lower cost. This would open up the market for the installation of TPV systems globally, potentially putting the technology within the reach of the domestic consumer and providing a viable option for a "green", clean source of energy for industrial processes.
