Mykytyuk P. Soil Thermal Energy Thermoelectric Conversion Devises

The thesis deals with a research into the use of thermal energy of near-surface soil layer to be converted into electric power by means of thermoelectric devices - soil thermoelectric generators (STEG). The possibility of creating STEG has been theoretically and experimentally proved. In particular, the basic physical regulations of the devices' work that should be used in the design and operation of STEG have been formulated. Physical regularities of concentration and dissipation of thermal flows in soil depending on thermal and physical characteristics of STEG have been established. The expressions for electric power of STEG with regard for dependence on the geometric dimensions of STEG and the depth of its location in soil have been derived. STEG optimization based on the thermal and physical characteristics of STEG and soil has been performed. Condition for optimal choice of STEG thermal resistance for concrete soil type and STEG form factor has been determined. The metrology basis and methods forstudy of thermopiles has been created to investigate thermal processes in soils with regard for their exposure to specific factors which determine the operating efficiency of STEG. The technique for manufacturing highly reliable thermopiles for STEG with service life up to 30 years has been developed. A series of large scale producible STEG have been developed that have no analogs and can be used in various climatic zones. Promising areas of STEG application and relevant lines of further investigation of STEG creation have been defined.