Question 26
Why is there a need for harnessing non-conventional sources of energy? How can energy be harnessed from the sea in different ways?
Question 26
Why is there a need for harnessing non-conventional sources of energy? How can energy be harnessed from the sea in different ways?
Conventional sources of energy are limited. They are rapidly being used up and will be exhausted soon. Therefore, there is a need for harnessing non-conventional sources of energy.
Energy from Oceans: It is a potential source of renewable energy. There are many forms of ocean energy.
(1) Ocean Thermal Energy (OTE) : There is always a temperature difference between water at the surface and at deeper level. This difference in temperatue is used to run a turbine and produces electricity. This form of energy is called ocean thermal energy which can be converted into electricity.
(2) Sea-Waves Energy: Energy from oceans is also available in form of sea-waves. Due to blowing of wind on the surface of the ocean, it has lot of kinetic energy due to high speed. It can be used to produce electricity. Some specially designed devices are set up in the sea which moves as the sea-waves pass them. Their movement can be used to drive dynamos which generate electricity.
(3) Tidal Energy: The rise of ocean water due to attraction of moon is called 'high tides' whereas fall of ocean water is called 'low tides'. The tidal waves rise and fall twice a day. The enormous movement of water between 'high tides' and 'low tides' provides a very large source of energy in the coastal areas of the world. Tidal energy can be harnessed by constructing a tidal barrage or tidal dam. The sea water rises during high tide trapped by the barrage is allowed to fall down on water turbines due to which they start rotating. The rotating water turbines drive generators which produce electricity.
(4) Energy from Salinity Gradient in Seas: The concentration of salts in water of different seas is different. The difference in concentration of salts in the water of two different seas is called 'salinity gradient'. The difference is concentration of salts where water from different seas meet can be used to obtain energy in usable form.
(5) Energy for Sea-Vegetation or Biomass: Sea-Vegetation or biomass is another indirect source of energy from the oceans. For example, the vast amount of sea-weeds present in oceans may provide an endless supply of methane as fuel in future.
Conventional sources of energy are limited. They are rapidly being used up and will be exhausted soon. Therefore, there is a need for harnessing non-conventional sources of energy.
Energy from Oceans: It is a potential source of renewable energy. There are many forms of ocean energy.
(1) Ocean Thermal Energy (OTE) : There is always a temperature difference between water at the surface and at deeper level. This difference in temperatue is used to run a turbine and produces electricity. This form of energy is called ocean thermal energy which can be converted into electricity.
(2) Sea-Waves Energy: Energy from oceans is also available in form of sea-waves. Due to blowing of wind on the surface of the ocean, it has lot of kinetic energy due to high speed. It can be used to produce electricity. Some specially designed devices are set up in the sea which moves as the sea-waves pass them. Their movement can be used to drive dynamos which generate electricity.
(3) Tidal Energy: The rise of ocean water due to attraction of moon is called 'high tides' whereas fall of ocean water is called 'low tides'. The tidal waves rise and fall twice a day. The enormous movement of water between 'high tides' and 'low tides' provides a very large source of energy in the coastal areas of the world. Tidal energy can be harnessed by constructing a tidal barrage or tidal dam. The sea water rises during high tide trapped by the barrage is allowed to fall down on water turbines due to which they start rotating. The rotating water turbines drive generators which produce electricity.
(4) Energy from Salinity Gradient in Seas: The concentration of salts in water of different seas is different. The difference in concentration of salts in the water of two different seas is called 'salinity gradient'. The difference is concentration of salts where water from different seas meet can be used to obtain energy in usable form.
(5) Energy for Sea-Vegetation or Biomass: Sea-Vegetation or biomass is another indirect source of energy from the oceans. For example, the vast amount of sea-weeds present in oceans may provide an endless supply of methane as fuel in future.
