Abstract
Ocean thermal energy conversion (OTEC) is a system to convert the ocean thermal energy, which is stored as the vertical temperature gradient in the ocean, into the electricity and the heat exchanger performance is significantly important. Theoretical maximum power output and the relationship between heat exchanger performances have been formulated in finite-time thermodynamics. And considering the seawater intake pumping powers in OTEC system, the thermal efficiency in case of the maximum net power has shown by introducing the ideal heat exchanges from heat source to heat engine. Considering the OTEC system without seawater intake system, the required pumping power of surface and deep seawaters will be the same magnitude of power as the generated power in the heat engine, and they might be able to get over the generated power due to the balance of the heat transfer performance and pressure drop in the heat exchangers. For each heat exchangers, heat transfer performance and pressure drop can be measured and summarized. However, for the application of the OTEC as an evaporator and a condenser, the effect of both characteristics on the net power in OTEC are same magnitude and very important. Therefore, the total performance evaluation method of heat exchangers is required for the selection and design of the heat exchangers as well as the development of the heat exchanger performance. This study describes about the theoretical relationship between heat transfer performance of heat exchangers including pressure drop and power output from the heat engine and shows the results of the comparison of the available power output from the power generation system using existing 3 plate heat exchangers (PHEs).