Materials and device designs for thermophotovoltaic power conversion

Abstract

Two IV–VI semiconductor alloys, Pb0.81Sn0.19Se and Pb0.8Sr0.2Se, are proposed for use in designing multiple quantum well (MQW) materials and devices for thermophotovoltaic (TPV) power conversion. These materials can be epitaxially grown on silicon substrates, so they offer the potential for a low cost TPV device manufacturing technology. MQW materials examples are provided for fabricating triple junction TPV devices for power conversion with a 1400°C radiator. Optimal n‐type and p‐type layer thicknesses for each junction were determined using internal quantum efficiency expressions derived assuming all photogenerated charge collection is by diffusion. Depending on MQW material quality and assumed optical absorption levels, predicted power generation for current matched triple junction devices ranged from 1.7 to 4.6 W/cm2 and power conversion efficiencies ranged from 15.9% to 35.7%. These device performance parameters were used in a levelized cost of energy (LCOE) calculation to predict the cost of energy provided by TPV devices with a molten silicon thermal energy storage system. Results show that even for TPV devices fabricated from low quality materials, such energy storage systems will have a low enough LCOE to be competitive with other forms of energy storage and power generation.