Low grade heat (<100°C) is currently converted into electricity by organic rankine cycle (ORC) engines. ORC engines require certain threshold to operate as the organic fluid generally boils at more than 50°C, and fails to operate at lower temperature. Thermoelectric generators (TEGs) can operate at very low temperature differences and can be good candidate to replace ORC for power generation at low temperatures. In this paper, the potential of power generation from TEG and salinity-gradient solar pond (SGSP) was investigated. SGSP is capable of storing heat at temperature up to 80°C. The temperature difference between the upper convective zone (UCZ) and lower convective zone (LCZ) of a SGSP can be in the range of 40°C 60°C. This temperature difference can be used to power thermoelectric generators (TEG) for electricity production. This paper present result of a TEG system designed to be powered by the hot and cold water from the SGSP. The system is capable of producing electricity even on cloudy days or at night as the SGSP acts as a thermal storage system. The results obtained have indicated significant prospects of such system to generate power from a low grade heat for remote area power supply.
Small Scale Power Generation using Low Grade Heat from Solar Pond
