Near-room-temperature thermoelectric materials and their application prospects in geothermal power generation

In recent years, due to the shortage of fossil fuel energy and the deterioration of the environment, increasing attention has been paid to the utilization of geothermal power, especially medium–low-temperature geothermal energy, which occupies a large proportion of hot water resources. This paper summarizes the research status of Bi2Te3-, MgAgSb-, Mg3Sb2-, Mg2(Si,Sn,Ge)- Ag2Se-and AbSbTe2-based near-room-temperature thermoelectric (TE) materials and summarizes the research results of TE technology used in geothermal water power generation. TE power generation technology can directly transform heat into electricity by TE devices, with the advantages of environmental protection, low carbon emissions, no mechanical moving parts, high thermal and mechanical stability and no noise. The improving performance of the investigated TE materials suggests that TE power generation technology is the key technology for clean geothermal power generation. Future research directions include further improving the TE performance, reducing costs and enhancing the research and design of TE devices and power generators.