1-4. Principle of OTEC #2 Flow of Working Fluid 1. Ammonia liquid is pumped up into the evaporator. 2. Warm surface seawater evaporates the ammonia liquid. 3. Ammonia vapor turns the turbine and generates electricity. 4. In the condenser, cold deep seawater condenses ammonia vapor. 5. Ammonia liquid is again pumped up into the evaporator.