Question

A certain form of energy is available due to the difference in the temperature of water at the surface of the ocean and its deeper levels.

(a) Name the form of energy.
(b) Is this energy ultimately derived from the sun or not?
(c) Explain how this form of energy can be converted into electricity.
(d) What is the minimum temperature difference in water at the surface of ocean and its deeper level which is required to operate power plants based on is energy?

Answer 1

(a) Ocean thermal energy
(b) Yes. The water at the surface of an ocean gets heated by the heat of the sun and attains a higher temperature than the colder water at deeper levels. So, ocean thermal energy is derived from the sun.
(c) In ocean thermal energy conversion plants, the warm surface water of the ocean is used to boil a volatile liquid such as ammonia or a chlorofluorocarbon. This produces high-pressure vapour, which is used to turn the turbine of a generator and produce electricity.
(d) 20 degrees Celsius