Simulation investigation of high-efficiency solar thermoelectric generators with inhomogeneously-doped nanomaterials

By introducing an inhomogeneously doped nanostructure thermoelectric generator (TEG) with a delta-like electronic density of states (DOS), a novel model of the solar TEG (STEG) with high conversion efficiencies is established. The STEG is composed of a flat-panel collector without optical concentration, but with thermal concentration, and a TEG in a vacuum enclosure. Reversible electron transport is achieved by designing quantum-confined electrons in thermoelectric materials. The maximum efficiency calculated herein is much larger than that previously reported. Influences of the current density, thermal conductivity, and energy band width of the electronic DOS on the performance are revealed. The optimization problems of the system are discussed. Results show that the STEG made of nanostructure materials, permitting the electron transport to approach energy-specific equilibrium, possesses great potential to increase solar energy conversion efficiencies.