1. Why is there a need for harnessing non-conventional sources of energy? How can energy be harnessed from the sea in different ways?

Soln:

Following are the reason for the need to harness non-conventional sources of energy.

1. Conventional sources are exhaustible source of energy and they will get exhausted in the near
2. Non-conventional source of energy did not lead to environmental

Energy can be harnessed from the sea in following ways

Tidal energy:

Tidal energy is harnessed by constructing a dam across a narrow opening to the sea. A turbine fixed at the opening of the dam converts tidal energy to electricity. As you can guess, the locations where such dams can be built are limited.

Wave energy

The kinetic energy possessed by huge waves near the seashore can be trapped in a similar manner to generate electricity. The waves are generated by strong winds blowing across the sea. Wave energy would be a viable proposition only where waves are very strong.

Ocean Thermal Energy

The water at the surface of the sea or ocean is heated by the Sun while the water in deeper sections is relatively cold. This difference in temperature is exploited to obtain energy in ocean-thermal-energy conversion plants.