Solar Thermoelectric Generator for Micropower Applications

Solar thermoelectric generators (STG) using cheap parabolic concentrators with high-ZT modules can be a cost-effective alternative to solar photovoltaics for micropower generation. A thermodynamic analysis is presented for predicting the thermal-to-electrical conversion efficiency for the generator. With solar concentration of 66× suns, a system efficiency of 3% was measured for a commercial Bi2Te3 module with output power of 1.8 W. Using novel thermoelectric materials such as n-type ErAs:(InGaAs)1−x(InAlAs)x and p-type (AgSbTe)x(PbSnTe)1−x, a conversion efficiency of 5.6% can be achieved for a STG at 120× suns.