Wind Energy

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Introduction to Wind Energy

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As fossil energy supplies dwindle, the development of alternative energy sources has become a necessity. Simultaneously, global energy demand is increasingly rising, placing the planet on the brink of a global energy crisis. Furthermore, the widespread use of traditional energy sources pollutes the atmosphere and leads to global warming. Wind and other renewable energy sources, on the other hand, are feasible and clean alternatives to fossil fuels. The wind is one of the most cost-effective and efficient renewable energy sources because of its low operating costs and broad availability. One of the fastest-growing clean energy technologies is wind power. Globally, consumption is growing, partially due to lower prices. According to IRENA's latest statistics, global installed wind-generation capacity onshore and offshore has increased by nearly 75 times in the last two decades, from 7.5 gigawatts (GW) in 1997 to 564 GW in 2018. Wind energy production more than doubled between 2009 and 2013, accounting for 16 per cent of all renewable energy generation in 2016. Wind speeds are high in many parts of the world, but the best locations for producing wind power are often remote. Offshore wind power has a lot of promise.

Wind Turbine

Wind turbines have been around for over a century. Engineers began attempting to harness wind energy to generate electricity after the invention of the electric generator in the 1830s. In 1887 and 1888, wind power was produced in the United Kingdom and the United States, but modern wind power is thought to have been invented in Denmark, where horizontal-axis wind turbines were installed in 1891 and a 22.8-meter wind turbine was put into service in 1897.

The wind is generally used to generate electricity by using the KE (kinetic energy) created by air in motion. Wind turbines or wind energy conversion systems convert this into electrical energy. The blades of a turbine are first struck by the wind, which causes them to rotate and transform the turbine connected to them. By moving a shaft connected to a generator and thereby generating electrical energy by electromagnetism, kinetic energy is converted to rotational energy. The size of the turbine and the length of its blades determine the amount of power that can be harvested from the wind. The output is proportional to the rotor's dimensions and the wind speed's cube. Wind power capacity increases by a factor of eight as wind speed doubles, according to theory.

Types of Wind Turbines

Wind turbines come in a variety of sizes. The blade length is the most important factor in deciding how much electricity a wind turbine will produce. Small wind turbines that will power a single home can generate up to 10 kilowatts of electricity (kW). Wind turbines with electricity-generating capacities of up to kilowatts (10 megawatts) are currently in use, and larger turbines are being built. Large turbines are often clustered together to form wind power plants, also known as wind farms, which provide electricity to grids. Wind turbines can be divided into two categories:

  1. Horizontal-axis turbines

  2. Vertical-axis turbines

Horizontal-axis Turbines

Horizontal-axis turbines have three blades, which are similar to aeroplane propellers. The main horizontal-axis turbines have blades that are more than 100 feet long and are as tall as 20-story buildings. More electricity is produced by taller turbines with longer blades. Almost all wind turbines in operation today are horizontal-axis turbines.

Vertical-axis Turbines

Blades are connected to the top and bottom of a vertical rotor in vertical-axis turbines. The Darrieus wind turbine, named after the French engineer Georges Darrieus, who patented the concept in 1931, resembles a massive two-bladed egg beater. The vertical-axis turbine can be 100 feet tall and 50 feet wide in some models. Since vertical-axis wind turbines do not work as well as horizontal-axis turbines, they are rarely used today.

Use of Wind Energy

  • Wind energy is a cost-effective alternative. After the production tax credit, the land-based utility-scale wind is one of the cheapest energy sources available today, costing 1–2 cents per kilowatt-hour. Wind energy mitigates the market volatility that fuel prices bring to conventional sources of energy since its power is sold at a fixed price for a long period of time and its fuel is free.

  • Wind will create jobs. The wind industry in the United States employs over 1 lakh people, and wind turbine technician is one of the fastest-growing occupations in the nation. The wind can sustain more than 6 lakh jobs in manufacturing, installation, maintenance, and supporting services by 2050, according to the Wind Vision Report.

  • It's an environmentally friendly fuel source. Wind energy does not pollute the environment in the same way that power plants that burn fossil fuels, such as coal or natural gas do, emitting particulate matter, nitrogen oxides, and sulphur dioxide, which cause public health issues and economic losses. Wind turbines do not emit any pollutants into the atmosphere that cause acid rain, smog, or greenhouse gases.

  • The wind is a renewable energy source that can be used in the home. The wind supply in the United States is plentiful and unrestricted. Wind power capacity in the United States has increased at a rate of 15% per year over the last ten years, making it the country's largest renewable energy source.

  • It is sustainable. Wind is a form of solar energy. Winds are caused by the sun's heating of the atmosphere, the Earth's rotation, and the irregularities on its surface. The energy generated by the sun and the wind can be harnessed to send power through the grid for as long as the sun shines and the wind blows.

  • On existing farms or ranches, wind turbines may be built. This has a significant economic impact in rural areas, where the majority of the best wind sites are located. Farmers and ranchers will continue to use the property because wind turbines only take up a small portion of it. For the use of the property, wind power plant owners pay rent to the farmer or rancher, providing additional revenue to the landowner.

Challenges of Wind Power

  • On a cost basis, the wind power must also compete with traditional generation sources. Even though the cost of wind power has fallen significantly in recent decades, wind projects must be able to compete economically with the least costly source of energy, and some areas might not be windy enough to be cost-effective.

  • Strong land-based wind sites are commonly found in remote areas, far from the cities that demand electricity. To get the electricity from the wind farm to the city, transmission lines must be installed. Building only a few of the already-proposed transmission lines, on the other hand, could drastically reduce the costs of expanding wind energy.

  • Wind energy production may not be the most cost-effective use of land. Alternative uses for land that may be more valuable than power generation must compete with land appropriate for wind turbine installation.

  • Turbines have the potential to pollute the environment with noise and odour. While wind power plants have a lower environmental impact than traditional power plants, there is concern about the noise produced by the turbine blades and the visual impact on the landscape.

  • Wind turbines have the potential to damage local wildlife. Birds have been destroyed by flying into turbine blades that are spinning. The majority of these issues have been addressed or significantly reduced as a result of technological advancements or proper wind plant placement. Wind turbine blades have also killed bats, and research is currently underway to develop and strengthen ways to mitigate the effect of wind turbines on these animals. Wind projects, like all energy sources, have the potential to alter the ecosystem on which they are installed, potentially reducing the habitat's suitability for some species.


A windmill is a mechanism that uses the kinetic energy of the wind to produce mechanical energy. The windmill's blades spin in a clockwise direction at all times. Daniel Halladay of the United States built the first windmill in the year 1854.

Types of Windmills

There are two types of windmills depending upon the axis of rotation:

  1. Vertical axis windmills

  2. Horizontal axis windmills

  • Post mill

  • Smock mill

  • Tower mill

  • Fan mill

Components of Windmill

The following are the parts of a windmill:

  • Blades: These are the most important parts of the windmill since they regulate the rotor speed.

  • Rotor: A propeller is also known as a rotor.

  • Anemometer: An anemometer is a device that measures wind speed.

  • Tower: The support structure that holds the blades and propeller together is known as the tower.

Working of Windmills

After a lot of trial and error, the number of blades on the windmill was calculated. Three blades were discovered to be the most effective, so every windmill has three blades. Windmills get their energy from the wind. When the blades come into contact with the wind, they travel in such a way that the shaft begins to spin, producing electricity. Mechanical energy is converted into electrical energy by the generator.

Use of Windmills

The main aim of a windmill is to transform wind energy into electrical energy, and once that energy is produced, it can be used in the following ways:

  1. To pump groundwater.

  2. Oil extraction from the seeds.

  3. The grains are milled.


Turbines are a relatively new form of wind-energy technology. The turbine, unlike the windmill, is only used as a stand-alone device when only small amounts of wind energy are needed. Small-scale multi-megawatt wind farms and large-scale multi-megawatt wind farms are more common. Wind farms are increasingly popular on ridges, open pastures, and plains, as well as offshore wind farms in the ocean, as demand for renewable energy and wind power increases. Modern wind turbines are much more sophisticated than mills. They have big blades attached to the base, which makes them identical. A gearbox and a generator are located within the turbine. The horizontal-axis turbine, which has a few longer blades that resemble an aeroplane propeller, is the most well-known. The vertical-axis turbine, on the other hand, is a lesser-known form with shorter and wider blades.

FAQ (Frequently Asked Questions)

1. What is a Wind Turbine?

Ans: Wind energy is converted into electricity by a wind turbine, which can then be used to power electrical devices, stored in batteries, or distributed over power lines.

2. What is the Mechanism of a Windmill?

Ans: Windmills transform wind energy directly into mechanical energy for activities like milling grain—the term's origin—or pumping water, which is what most windmills on farms are used for. A windmill's spinning vanes turn a camshaft, which is connected to the work machinery through gears and rods. The job receives all of the force.

3. What is the Difference Between Wind Turbine and Windmill?

Ans: A wind turbine is not the same as a windmill or a wind generator. Windmills and wind pumps have existed for centuries. Windmills have been used to grind grain, and wind pumps have been used to pump water from the ground and drain it to make room for new growth. Wind turbines produce electricity in the same way as hydroelectric dams and nuclear power plants do, and new wind turbine technology has put them in a class of their own. Aside from a few mechanical features, the only thing they have in common is that they're all driven by wind.