Co-generation of heat and power in a thermoelectric system equipped with Fresnel lens collectors using active and passive cooling techniques

A Fresnel lens collector was incorporated in a thermoelectric solar system for combined heat and power (CHP) generation. Two passive (heat pipe thermo-siphon) and active (pumped circulation) cooling systems were used for transferring heat from the cold side of thermoelectric generators to a thermal energy storage. Experimental results from the solar thermoelectric (STE) CHP system equipped with passive cooling showed that the maximum output power of the thermo-siphon from the thermoelectric generators (TEGs) was 70 W/m2. This system also generated 3.8 kW/m2 thermal power in a clear September day from 10:30 to 15:30. The thermal efficiency of the thermo-siphon configuration was 18.05% and its total efficiency (electrical and thermal efficiency) was 18.39%. Additionally, experimental results of the STE CHP system equipped with active cooling were indicative of 33.15% thermal efficiency and 33.88% total efficiency at a flow rate of 700 ml/min. The maximum generated power and stored thermal energy of the system were 143 W/m2 and 6.5 kW/m2, respectively.