A High-temperature, High-efficiency Solar Thermoelectric Generator Prototype

Abstract

Solar thermoelectric generators (STEGs) have the potential to convert solar energy at greater than 15% efficiency. This project investigates the system design, the necessary thermoelectric and optical technologies, and the economic feasibility of the STEG approach. A STEG is a solid-state heat engine that converts sunlight directly into DC electricity through the thermoelectric effect. STEGs consist of three subsystems: the solar absorber, the thermoelectric generator (TEG), and the heat management system (insulation, heat exchanger, vacuum enclosure, etc.). This project will integrate several state-of-the-art technologies to achieve high efficiency, including next- generation materials for TEGs, high-temperature solar-selective absorbers, and thermal cavities. We will test STEGs at NREL's high flux solar furnace (HFSF) and perform analysis of parasitic losses and lifetime analysis to optimize prototype operation. Equally important for this technology is the development of a cost model to determine the economic competitiveness and possible application niches for STEG technologies. We report on first-order economic analysis to identify the most promising pathways for advancing the technology.