Ocean Thermal Energy
- The surface of the ocean is at a higher temperature than the layers below. This is because of the sun’s heat warms up the upper layers of the sea.
- This temperature difference is exploited to generate energy
- A minimum temperature difference of 20 degrees C is needed between water at the surface and at a depth of about 2 km.
- This requires Ocean Thermal Energy Conversion plants which converts ocean thermal energy to electricity.
Ocean Thermal Energy Conversion plants
- The water at surface of the ocean which is at higher temperature vaporizes liquid ammonia.
- The vapour ammonia now moves the turbine which generates electricity.
- The vapour ammonia then, is condensed using the water at the bottom layers of the ocean. It now again becomes liquid ammonia.
- This is again heated by the heat from the top layers and the process continues.
Advantages of Ocean Thermal Energy
Disadvantages of Ocean Thermal Energy
· More reliable (more than solar/wind)
· Low maintenance cost
· Initial cost is very high
· Not environment friendly because construction of such plants could harm aquatic plants and animals.