Optimization of an ocean thermal energy conversion system

The optimum performance of a simple Rankine cycle ocean thermal energy conversion plant is investigated analytically. It is shown that the ratio of maximum net power output to heat exchanger surface area varies as H(Δt − t₀)² where H describes the overall heat transfer properties of the evaporator and condenser, Δt is the temperature difference between the warm and cold sea water supplies, and t₀ is a parameter depending primarily upon the pressure drops across the warm and cold sea water pumping systems. The model is relatively insensitive to the choice of working fluid, although ammonia is used as the illustrative example.