Considerations on the use of thermoelectric generators at low temperatures to recover waste geothermal energy

This paper presents considerations on the possibility to use thermoelectric generators at low temperatures to recover waste heat recovery applications, especially from geothermal energy. Thermoelectric generators have a satisfactory efficiency, when they are usually used in conditions with high gradient of temperatures. However, there are many applications, which lose important quantities of energy even at low temperatures, in the order of tens of degrees. To evaluate the operation of a thermoelectric generators modules set, the authors have realized an experimental prototype and investigate its electrical output characteristic at low temperature differences. The purpose of this study was to investigate the possibility to obtain electricity, into an isolated place, but with practical possibility to assure temperature gradients.