Hydropower is another source of non renewable energy which is an indirect form of solar energy. Hydropower is, in fact, considered the most environmentally friendly energy source among the rest, given its low harmful effects.
An efficient source of energy
Hydropower relies on a structural dam construction which alters the natural flow of the water. This artificial flow of water is manoeuvred in such a way, so that the kinetic energy of the water dropping from a high potential to low potential powers up the turbines, which are ergo connected to a generator. The powerful downflow of the water spins the turbine, hence generating electricity with the help of generators.
This whole system of energy generation is an endless and constantly recharging structure of the water cycle which generates electricity, without even eliminating or reducing any amounts of water in the process.
Types of Dams
There are many types of water dams:
1. Impoundment– It is the most common of the various water dams in which water is mainly stored in an elevated reservoir and is dropped through the spinning turbines.
2. Diversion– Here a portion of the river is channelled through a canal to use the natural kinetic energy to turn the turbines.
3. Pumped Storage– This is basically like a giant battery. Water is pumped from a lower reservoir to an elevated one to store energy generated by other methods. When the demand for energy is high, water from the higher reservoir is released to the lower reservoir thus generating electricity using the turbines and the generator.
HydroElectric Power Plants – Where Energy Gets Made
Hydroelectric power plants also come in different sizes – large hydropower with the capacity of more than 30 MW, small hydropower with the capacity lying between 100 KW and 10 MW, and lastly micro hydropower with the capacity of up to 100 KW.
Small scale hydropower plants can prove to be very beneficial for small communities at remote locations. Naturally, most hydropower plants are located near natural water bodies. The energy generated by the plant depends on the volume of the water, as well as the change in the elevation from one point to another. More the elevation and greater the flow, results in higher electricity generation.
Constructing and using a water dam is also one of the most cost-friendly ways, which makes its usage even more prevalent. 99 % of electricity in Norway is generated with hydropower plants. World’s largest hydro plant is the 22.5 gigawatt Three Gorges Dam in China, which produces 80 to 100 terawatt-hours per year. This much electricity is enough to supply 70 million to 80 million households. India ranks 5th in the world for potential hydropower capacity, which stands at around 50 GW. Above India are China, Brazil, USA and Canada in the consumption scale of hydropower.
According to IHA, our country so far has 197 hydro plants which are capable of generating more than 25MW of electricity and 9 pumped storage stations. The public sector operates more than 90% of the country’s hydroelectricity via companies like SJVNL, NHPC, NEEPCO, and NTPC-Hydro.