Wind Energy
Energy is the ability to do work, and we learned that wind is moving air created by the heat of the sun. Wind energy can be simply defined as energy from the wind that can do work and create electricity.
When we talk about energy created by movement of the wind, we are talking about kinetic energy. You can recall this term by remembering that the word 'kinetic' originates from the Greek language and means 'to move.' In order to utilize the kinetic energy of the wind for electricity production, we need a way to harness its power. To do this, we use wind turbines.
Wind turbines are machines with rotors and blades that convert the kinetic energy of the wind into mechanical energy, which is then converted to electricity. The word 'turbine' comes from the Latin language and means 'something that spins.' So you can think of a wind turbine as something that spins in the wind to generate electricity. The mechanical energy produced from the spinning blades of the turbine is transferred to a generator that converts the mechanical energy into electricity.
It might help to think of a wind turbine as the opposite of a fan. A fan plugs into your wall and uses electricity to spin its blades and make wind. A wind turbine works in reverse. It uses the wind to spin its blades to generate electricity.
Wind turbines can work alone, but they are often found together on wind farms, which are areas of land that contain large groupings of wind turbines. The individual wind turbines within a wind farm work together for increased electricity production. Because wind speeds are often higher over water, there are some wind farms built in bodies of water. These wind farms are referred to as offshore wind farms. Offshore wind farms can increase energy production, but are often more expensive to construct than wind farms on land.
Pros of Wind Energy
There are a number of pros to wind energy. Wind energy is renewable energy. This means that as long as the sun continues to shine, we will have wind to generate electricity. Wind energy is also clean and green. Currently, developed countries gain most of their electricity and energy needs from fossil fuels, like oil, coal and natural gas. However, burning fossil fuels creates greenhouse gases that are thought to contribute to global climate change. With wind energy, there is no greenhouse gas production during operation.
Speaking of operating wind turbines, we see that wind energy comes with low operating costs. After the wind turbine is built and set in place, the power generated is essentially produced at no cost. We also see that wind energy has a tremendous potential to become a leading energy source. This is thanks to the fact that it is highly abundant, and wind energy can work anywhere the wind speeds are sufficient, which is typically best over 10 miles per hour.
Cons of Wind Energy
Now there are also cons to wind energy, with the biggest disadvantage being the fact that wind is inconsistent and unpredictable. If the wind is not blowing, the blades of the wind turbine do not rotate and no electricity is generated. Because of winds' unpredictability, wind energy often needs to work in tandem with other energy generation systems, including those that use fossil fuels.
Now while it is true that there are very few costs associated with the operation of a wind turbine, there are costs associated with building and setting up the turbines. This initial cost barrier could delay the implementation of wind energy in some areas of the world. In the United States, wind energy plants rely on government subsidies to lower initial costs.
Opposition to wind farms comes from the fact that wind turbines generate noise that is upsetting to some people who live nearby. Also, some people consider wind turbines in their backyard to be an eyesore because they disrupt the scenery. In fact, the acronym NIMBY, which stands for Not In My BackYard, is used to describe opponents to wind farm developments who like the idea of energy generation by the wind, but do not want the wind turbines in their area.
Environmentalists are concerned that wind farms could present a threat to wildlife. Even though wind turbine manufacturers have made positive design changes that have limited the deadly impact of turbines, birds and bats can be injured or killed by the spinning blades of wind turbines.
Lesson Summary
Let's review. Wind is created because the sun unevenly heats the surface of the earth. By harnessing the wind, we can generate wind energy, which is energy from the wind that can do work and create electricity. To capture wind energy, we use wind turbines. Wind turbines are machines that convert the kinetic energy of the wind into mechanical energy, which is then converted to electricity.
Wind turbines are often found together on wind farms, which are areas of land that contain large groupings of wind turbines. Wind farms built on bodies of water are referred to as offshore wind farms. There are a number of pros to wind energy. Wind energy is renewable energy and is also clean and green, because operation of a wind turbine does not create greenhouse gas emissions. Wind energy comes with low operating costs and has a tremendous potential to become a leading energy source, thanks to the fact that it is highly abundant.
There are also cons to wind energy. Wind is inconsistent and unpredictable. If the wind is not blowing, no electricity is generated. There is an initial cost barrier that comes with building and installing wind turbines. And, opponents to wind farms point to the fact that wind turbines generate noise and disrupt the scenery. Although they see the benefits of wind, when it comes to wind turbines, they say Not In My BackYard, or NIMBY. Wind farms could present a threat to wildlife by killing birds and bats that fly into the blades of the turbines.
Learning Outcomes
After viewing this lesson, you should be able to:
- Define what wind energy is and how it is produced
- Explain the pros and cons of using wind as an energy source
