Question

What are the limitations of the energy that can obtain from the oceans?

Answer 1

Tidal energy, wave energy, and ocean thermal energy are various forms of energy that can be obtained from the sun. But there are several limitations to harness these energies. Those limitations are
(i)High dams are required to be built to convert tidal energy into electricity which incurs lot of cost.
(ii)Very strong waves are required, which are not possible all the time.
(iii)Tidal energy depends on the relative positioning of the Earth, moon, and the Sun. 
(iv) To harness ocean thermal energy the difference in the temperature of surface hot water and the cold water at depth must be 20ºC or more.
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Answer 2

The limitations are described below :

1. For obtaining energy from oceans, construction of dams is must so that the tidal energy gets converted into electrical energy. And construction such structures requires lots of cost.

2. Also, in most of the time strong waves are needed. But it is not possible to obtain such waves every time.

Because of these reasons, we cannot obtain energy from oceans easily.