Wind energy may be used to generate electricity using wind turbine. Wind energy is considered as an inexpensive and non-polluting means of electricity generation. Wind mills have moderate to low installation costs and are easy to construct. The land around wind mills may be used for other activities. The major drawback of wind energy is the significant reduction in power output during low winds. Furthermore, it may harm birds and cause noise pollution.
The drag caused by draught of wind, rotates the blades of turbine, which turns gears in a generator behind the blades and inside the turbine. The generator converts the kinetic energy of the rotating blades into electrical energy, which transmits the same to the grid (Maczulak 2010).
Wind farms, comprising of hundreds of systematically arranged turbines, are developed along coasts or on plains, which receive steady winds in all seasons (Maczulak 2010).
Types of wind turbines depending on axis of rotation (Hodge 2017):
HAWT devices rotate in the horizontal plane. These wind turbines require a mechanism for yaw control to keep them pointed towards wind.
VAWT devices rotate in the vertical plane. They don’t require yaw control mechanisms.
HAWT devices are more common than VAWTs. The most common configurations for the HAWT are the two- and three- bladed, the windmill, and the sail wing. The two- and three-bladed wind turbines can be either upwind or downwind, with upwind being the most common. (Hodge 2017)
The total wind power potential in India is estimated at 302,251 MW at 100 m hub height (MOSPI 2019). The wind energy is the largest contributor to the grid-interactive renewable power installations in India, followed by solar energy. The total installed capacity of wind power plants in India is over 35.6 GW as on March 31, 2019 (MNRE 2020). Illustration 1 shows the wind farms in part of Jaisalmer district of Rajasthan. Illustration 2 shows wind mills along Saurashtra coast of Gujarat.
Illustration 1: Wind Farms of Jaisalmer District, Rajasthan
Illustration 2: Wind Mills at Saurashtra Coast, Gujarat
Hodge, B. K. 2017, Alternative Energy Systems and Applications, Second Edition, John Wiley & Sons, Ltd., Hoboken, NJ, USA.
Maczulak, A. 2010, Renewable Energy, Sources and Methods. Facts On File, Inc. New York.
MNRE. 2020, Ministry of New and Renewable Energy (MNRE), Available: https://mnre.gov.in/solar/solar-ongrid/, Accessed: July 22, 2020.
MOSPI. 2019, Energy Statistics 2019. New Delhi: Ministry of Statistics and Programme Implementation (MOSPI).
NITI Aayog. 2015, Report of the Expert Group on 175 GW RE by 2022. New Delhi: NITI Aayog.