Tidal Energy in India:
Tidal Energy, also known as Tidal Power is classified as an alternate energy or better known as the renewable source of energy. It is one of the forms of hydropower energy that exercises energy of the oceanic tides to generate electricity. In this article, study about tidal energy in India.
What is a tide?
Tide is the periodic shift or movement of vast quantities of water resulting from the gravitational forces of the sun and the moon acting on Earth’s water bodies. These vertical shifts or movement of water is known as tides.
In normal course each day experiences two high tides and two low tides. High tide is a situation where the water of the ocean bulges towards the shore i.e towards the moon because of the gravitational forces between moon and Earth, then High Tide occurs.
But when the gravitational force between the Earth and the Moon is at right angles to each other, this gravitational force is weak and water flows in some other location i.e this is the time when the sea is at its lowest level.
Hence, this is the reason it is one of the most viable forms of energy generation this is because it is sure that each day we will experience twice high tides and low tides respectively, so it’s predictable as compared to solar and winds energy.
Tidal Energy in India: Generation
As discussed above tidal energy in India is generated by the movement of oceanic tides. As the celestial bodies- Earth, Sun, and the Moon change their positions throughout the year with these changes in position the gravitational pull exerted by these bodies result in water movements and thus the energy created can be harnessed to generate electricity. Here the motion of the water is transformed into energy.
Types of Tidal Energy Generation
- Tidal Barrage
A Tidal Barrage as the name suggests uses tidal barrages (a low dam set-up) to generate electricity. It uses the potential energy in the difference in height between high and low tide. When sea level rises and high tide begins to come in the energy from this tide is channelized through the dams which has underwater tunnels that allows the sea water to flow through them, as water passes through these tunnels, the turbine generators attached to these tunnels whirl the sea water, converting the energy of this tide into mechanical energy, thereby generating tidal electricity.
- Tidal Stream Generator
This method of tidal energy generation exercises the kinetic energy of the flowing water to power turbines placed beneath the water. Similar to wind power generation, where water flows across the rotor blades which rotates the turbine and thus tidal streams are formed by the constant incoming and outgoing of the tide, thereby generating tidal energy
These are the two ways of generation of tidal energy in India.
Advantages of Tidal Energy Generation
- Tidal energy is the most sorted and renewable source of energy because the energy it produces has lower cost and it’s clean because it uses no fuel so it’s environment-friendly and no waste by-products are produced either
- Tidal energy has the potential to produce a great deal of free and green energy. Hence, it’s a bio-friendly energy
- Tidal energy is not expensive to be conducted and is easy to maintain compared to other forms of renewable energy sources
- Low visual impact as the tidal turbines is mainly if not totally submerged beneath the water.
- Low noise pollution as any sound generated is transmitted through the water.
- High predictability as high and low tides can be predicted years in advance and there is a definite surety of high and low tides occurring twice a day respectively
- Tidal barrages provide protection against flooding and land damage and tidal stream generators cause lesser or no harm to the natural landscape
- Large tidal reservoirs have multiple uses and can create recreational lakes and area
Disadvantages of Tidal Energy Generation
- Although the occurrence of tides can be predicted tidal energy is not always a constant energy source because the energy generated from the tides depends completely on the strength and flow of the motions of the water, which itself is dependent on the gravitational effects of the celestial bodies- Earth, Moon, and the sun.
- Tidal Energy requires a suitable site, where the tides and tidal streams are consistently strong and can be harnessed
- In contrary to its installation and generation costs it should be able to withstand forces of nature thereby resulting in additional investment, apt construction and maintenance costs. The cost involved to send the generated power from the submerged devices to the land is high because it requires long underwater cables for the transmission
- Intermittent power generation only generates power ten hours a day during the outgoing and incoming of the tides
- Chances of increase in coastal erosion where the tides are concentrated.
- If not taken properly it can create a mess in the form of accumulated silt, sediments and pollutants within the tidal barrage from rivers and streams flowing into the basin as it is unable to flow out into the sea.
- Danger to marine animals like fish and other sea-life as they might get stuck in the barrage or get sucked by the force of tidal turbine blades.
- Many types of advanced tidal energy generation techniques like dynamic tidal power and tidal lagoon still cannot be put in action because of the complexities attached to tidal energy generation
Tidal Energy in India
As of March 2017, India announced of its 7500 Km long coastline, where the height of high tide was recorded over 5 mtrs higher than the low tide which can essentially capture the potential tidal power. The Ministry of New and Renewable Energy estimated that the country can produce 7000 MW of power in the Gulf of Khambhat in Gujarat, 1200 MW of power in the Gulf of Kutch in Gujarat and about 100 MW of power in the Gangetic delta of Sunderbans in West Bengal.
To know more about Ocean energy and its impacts on our environment, visit here.