A thermoelectric generator based efficiency booster for performance enhancement of natural circulation systems

To improve the performance of natural circulation based passive residual heat removal systems in a nuclear power plant, an efficiency booster has been developed using a thermoelectric generator (TEG) in this paper. The booster does not require any external power source to operate. The power comes from the temperature differential between the heat source and the heat sink. Modeling and analysis of three different booster architectures have been carried out. Furthermore, a lab-scale proof-of-concept experimental set-up has been constructed to valid effectiveness of the design. Results have consistently demonstrated that the booster can potentially improve the heat transfer capability by a factor of four over natural circulation loop in a passive residual heat removal system. For benchmarking purposes, the performance of the developed TEG based booster has been compared with that of a previously developed turbine based booster. Even though the degree of heat transfer enhancement of the former is lower than that of the latter, it can still significantly improve the heat transfer rate of a natural circulation system. The new design also has several unique advantages. The most notable one is that there are no moving components in the power generation units, which leads to improved reliability and reduced maintenance tasks.