Principle of working of OTEC: The water at the surface of the ocean is warmer than the water at deeper depths. This temperature difference can be used by Ocean Thermal Energy Conversion (OTEC) systems to generate electricity.

Working of OTEC:

• In OTEC plant, the energy of warm surface water is used to convert low boiling point liquid ammonia into gaseous state.
• The vapour of ammonia at high pressure is used to spin the turbines of generators converting the Ocean thermal energy to electricity.
• The used vapour pass through the condenser where cold water, pumped from the deeper parts of ocean condenses ammonia vapour back into a liquid.
• This process is repeated again and again ,to get continuous production of electricity.
  
• Essential condition for it to operate properly: The temperature difference between the warmer water at the surface and colder water at depths up to 2 km should be 293K (20°C) or more.