A Solar-Radiation-Powered Thermoelectric Energy Harvester based on Quasicrystal

Energy harvesting is an important research area of the Internet of Things (IoT), mainly in the so-called Internet of Natural Things (IoNT), which is an IoT technique applied to things found in the nature like trees, rocks, and animals that need to be powered by environmentally available energy. Among several energy harvesting solutions, the thermoelectric-based energy harvester is a very promising one and it is generally based on semiconductor-based thermoelectric generators (TEGs) where the output electric voltage is proportional to the applied temperature gradient on them. However, the most important natural energy source is the solar radiation that, when incident in a surface, warms it and, as a result, the surface achieves a homogeneous temperature, turning the TEG useless since temperature gradient is zero. A possible solution for thermoelectric energy harvesting directly from solar radiation is to provide a way to selectively absorb solar radiation using different surfaces with adequate properties to obtain a temperature gradient. In this paper, a solar-radiation-powered thermoelectric energy harvester is proposed. The proposed harvester is based on the use of a new kind of material, called quasicrystals, to build selective solar absorbers, therefore allowing energy harvesting directly from solar radiation. Experimental results show that the proposed system is capable of effective generation of electrical energy.