Question

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

Answer 1

Step 1: Non-conventional sources of energy

1. These sources of energy are also known as renewable sources of energy.
2. Non-conventional sources of energy are basically natural resources that do not cause pollution.
3. Solar energy, wind energy, tidal energy, biomass, etc are non-conventional sources of energy.

Step 2: Need for harnessing non-conventional sources of energy

1. The energy demands are rising as the population of worlds is increasing every day. The conventional resources like coal and petroleum are limited, thus alternate renewable resource is required for the future.
2. The non-conventional sources of energy are required because fossil fuels increase air pollution while non-conventional sources do not cause any pollution.

Step 2: Energy from seawater

1. Energy from sea water can be harnessed by using tidal, ocean thermal and wave energy.
2. Tidal energy is harnessed by building a dam over a narrow sea entrance. A turbine installed at the dam's entrance transforms tidal energy to electricity.
3. The sun heats the water at the surface of the sea or ocean floor, whereas the water in deeper regions is comparatively cool. This temperature gradient is used to generate energy in ocean-thermal-energy conversion plants.
4. Large waves along the seaside have kinetic energy that can be captured in a similar way to create power. Strong winds blowing over the water create the waves. Wave energy would be a feasible option only if the waves are quite powerful.

Hence, the need for harnessing non-conventional sources of energy is to reduce the pollution and the conventional sources are limited.