What is wind energy?

First, let’s understand how wind is created:

Wind is air in motion, it can be defined as a form of solar energy. Wind is caused by the uneven heat from sun and the rotation of the earth. The atmosphere is hit by the sun unevenly because of different scenarios like mountains, vegetation, desert lands or clouds. Air on surfaces with low temperatures sink while air on surfaces with higher temperatures rise. This process creates an atmospheric pressure that produces a large current of wind. This wind flow produces kinetic energy which is collected by wind turbines to generate electricity. Therefore, we can conclude that wind energy can be defined as the process in which the wind is used to create electricity.

How does it work?

Wind energy is created by wind turbines. The wind turns the blades, which spins a shaft that powers a generator that supplies an electric current. There are two main types of wind turbines; the horizontal-axis model (figure 1) and vertical-axis model (figure 2). Vertical-axis turbines consist of two or three blades that spin around a vertical shaft. Unlike horizontal-axis models, vertical-axis turbines have blades that can adapt to winds coming from any direction, and therefore no computer is needed for adjustment. However, vertical-axis turbines are less efficient than horizontal-axis turbines. This is because their blades are closer to the ground and the wind does not blow as fast on the land as it does in higher altitudes. Newer and more modernized models have a horizontal-axis. These type of wind turbines look like a fan but their functions are completely different. While a fan uses electricity to make wind, a wind turbine uses wind to create electricity. horizontal-axis turbines consist of two or three blades that spin around a horizontal shaft. The blades are attached together by a hub forming what is called a rotor. The rotor is then joined to a compartment called the nacelle. stored inside this compartment is a computer that tracks the wind's speed and direction. When the wind changes direction, the computer programs the nacelle to turn the rotor to the opposite direction. Wind turbines need the right amount of wind to function; they cannot work if there is not enough wind, but if the current of wind is too high they could possibly be damaged. Generally, wind turbines are grouped together into a single wind power plant, also known as a wind farm. A large wind power plant may consist of hundreds of wind turbines occupying several hundreds of square miles, this land is used for other purposes such as agriculture. For example, in West Texas most wind farms range from 2,000 acres to more than 100,000 acres. .

How much electricity can wind energy produce?

Wind energy is measured in megawatts (MW)

1 MW=1x10⁶ watts

The production of wind energy over time is measured in megawatt-hours (MWh) or kilowatt-hours (kWh) of energy. Production of power at the rate of energy is:

1 MW for 1 hour =1 MWh

1 kW=1000 watts

Modern wind turbines have power ratings ranging from 250 watts to 7 MW. An onshore wind turbine with a capacity of 2.5–3 MW has the ability to generate more than 6 million kWh in a year. This is enough to supply 1,500 average American homes with electricity.

Did you know?

Denmark is world's leader in wind power, approximately 20% of its electricity comes from wind turbines, both onshore and offshore.
Wind energy is the fastest growing segment of all renewables and it is expected to continue to grow for a least a decade.
One wind turbine can produce enough electricity to power 300 homes.
New wind farms are being developed in Texas under a state law enacted in 2005. The law set a statewide goal to install 5,880 MW of new renewable energy resources by 2015 and 10,000 MW of wind power by 2025. Texas has already met the 2015 goal and is on track to meet the 2025 goal by 2010. Most of this new energy will come from wind farms.