Investigation on the Performance of the 15kW OTEC System

In the paper, the performance of two cycle systems, Rankine and Kalina-11 (KSC-11) are compared. The conclusion of this comparison yields the Kalina-11 cycle superior. In the KSC-11 cycle, it is found that the optimal ammonia fraction exists in the system under a fixed turbine inlet pressure. And the corresponding optimal turbine exists in the system under a constant ammonia fraction. When the ocean temperature difference is 19°C, the ammonia fraction has little effect on the 15kW OTEC KSC-11 system maximal net power with the corresponding optimal turbine inlet pressure of 0.6∼0.75MPa. When the ammonia fraction is 0.95, the system has the best combined performance. And the corresponding optimal turbine inlet pressure is revealed to be 0.75MPa. The ratio of total heat exchanger area to net power produced γ is discovered to be 6∼7 m²/kW.