What is Wind Energy?
The terms “wind energy” and “wind power” both describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water), or can be converted into electricity by a generator.
The wind is an intermittent source of energy that cannot be dispatched when needed. Locally, there is a variable performance that is constant from year to year but changes significantly over shorter periods of time. Therefore, it must be used in conjunction with other power sources to ensure a reliable supply.
Wind Energy Basics
The wind is caused by the uneven heating of the atmosphere by the sun, fluctuations in the earth’s surface, and the earth’s rotation. Mountains, bodies of water, and vegetation influence the wind flow patterns.
Wind turbines convert the energy in the wind into electricity by rotating propeller-like blades around a rotor. The rotor turns the driveshaft, which turns an electric generator.
Three key factors affect the amount of energy a turbine can harness from the wind:
- Wind speed,
- Air density, and
- Swept area.
The equation for Wind Power
The amount of energy in the wind varies with the cube of the wind speed. In other words, when the wind speed doubles, there is eight times more energy in the wind (23 =2x2x2=8). Small changes in wind speed have a major impact on the power available in the wind.
Density of the air
The denser the air, the more energy the turbine receives. The air density varies with altitude and temperature. Air is less dense at higher altitudes than at sea level, and warm air is less dense than cold air. If everything else is the same, turbines will produce more power at lower altitudes and in places with cooler average temperatures.
Swept area of the turbine
The larger the swept area (the size of the area through which the rotor spins), the more power the turbine can capture from the wind. Since the swept area is A = pir2, where r = radius of the rotor, a small increase in blade length results in a larger increase in the power available to the turbine
Things You Didn’t Know About Wind Power
- Human civilizations have used wind power for thousands of years. Early forms of a windmill used the wind to crush grain or pump water. Today, modern wind turbines use wind to generate electricity. Learn how a wind turbine works.
- Today’s wind turbines are much more complicated machines than the traditional prairie windmill. A wind turbine consists of up to 8,000 different components.
- Wind turbines are Big. Wind turbine blades average over 190 feet long and turbine towers average 295 feet high – about the height of the Statue of Liberty.
- Higher wind speeds mean more electricity and wind turbines get taller to reach higher heights above the ground where it is even windier. Use the Department of Energy’s Wind Resource Maps to find the average wind speeds in your state or hometown. For more information on taller wind turbine opportunities, see a report from the Department of Energy’s National Renewable Energy Laboratory.
- Most of the components of wind turbines installed in the United States are manufactured here. There are more than 500 wind-related manufacturing facilities located across 43 states, and the U.S. wind industry currently employs more than 114,000 people.
- Offshore wind represents a major opportunity to provide power to highly populated coastal cities, and the nation’s first offshore wind farm was installed off the coast of Rhode Island in 2016. See what the Energy Department is doing to develop offshore wind in the United States.
- With North Carolina’s first utility-scale wind farm coming online in early 2017, there is now utility-scale wind power installed in 41 states. There is distributed wind installed in all 50 states plus Puerto Rico, Guam, and the U.S. Virgin Islands.
- The United States’ wind power capacity was 105.591 megawatts at the end of 2019, making it the largest renewable energy source in the United States. That’s enough electricity to offset the consumption of 29.5 million average American homes.
- Wind energy is affordable. Wind prices for power contracts signed in the last few years and levelized wind prices (the price the utility pays to buy power from a wind farm) are 2–4 cents per kilowatt-hour.
- Wind energy provides more than 10% of total electricity generation in 14 states, and more than 30% in Kansas, Iowa, and Oklahoma.
Advantages of Wind Energy
Harnessing wind to generate energy has its advantages and is an efficient option for many different parts of the world since it doesn’t depend on direct sunlight exposure like solar energy.
1. Wind Energy Is Clean and Renewable
Unlike coal, natural gas, or oil, generating electricity from wind doesn’t result in greenhouse gas emissions. While there are some environmental considerations that come with building large wind farms, once operational, wind turbines themselves don’t require burning any fossil fuels to operate.
Additionally, wind energy is completely renewable and will never run out. In opposition to traditional fossil fuels resources that replenish very slowly, wind naturally occurs in our atmosphere, and we don’t have to worry about supply issues in the future.
2. Free Fuel
Since wind turbines themselves run strictly on the power of wind-generated, there is no need for fuel. Once the turbine is complete and installed, it doesn’t need to be fueled or connected to power to continue working.
This also reduces the overall cost to continue to run large-scale wind farms in comparison to other forms renewable energies, which require may require some energy investment.
3. Wind Energy Has Low Operating Costs
As far as upfront costs go, wind farms or individual turbines can be expensive to install. However, once up and running, operating costs are relatively low; their fuel (wind) is free, and the turbines don’t require too much maintenance over the course of their lifetime.
4. Wind Energy Is Space-Efficient
Cumulatively, wind farms can take up a lot of land space; however, the actual turbines and equipment don’t use up a lot of real estate. This means that land used for wind turbines can often also be used for other purposes, such as farming
5. Advances in Technology
The latest advances in technology have transformed preliminary wind turbine designs into extremely efficient energy harvesters. Turbines are available in a wide range of sizes, increasing the market to many different type’s businesses and by individuals for use at home on larger lots and plots of land.
As technology improves, so do the functionalities of the structure itself, creating designs that will generate even more electricity, require less maintenance, and run more quietly and safely.
Disadvantages of wind energy
Although wind energy is a renewable, greener option of energy, it still has its disadvantages and limitations.
1. Wind energy is intermittent
A wind turbine’s effectiveness in generating electricity depends on the weather; thus, it can be difficult to predict exactly how much electricity a wind turbine will generate over time. If wind speeds are too low on any given day, the turbine’s rotor won’t spin.
This means wind energy isn’t always available for dispatch in times of peak electricity demand. In order to use wind energy exclusively, wind turbines need to be paired with some sort of energy storage technology.
2. Wind energy causes noise and visual pollution
One of the biggest downsides of wind energy is noise and visual pollution. Wind turbines can be noisy when operating, as a result of both the mechanical operation and the wind vortex that’s created when the blades are rotating.
Additionally, because wind turbines need to be built up high enough to capture a good amount of wind, the turbines can often interrupt otherwise scenic landscapes, such as mountain ranges, lakes, oceans, and more.
3. Wind plants can impact local wildlife.
A wind turbine’s blades are very large and rotate at very high speeds. Unfortunately, their blades can harm and kill species that fly into them, like birds and bats. The construction of wind farms can also disrupt the natural habitats of local species if not conducted in a sustainable manner.
However, these problems can be solved to some extent with technological advancements and properly-siting wind farms.
Wind turbines need to be built high in order to capture enough wind, which makes them a prominent part of any landscape. Some people find that large wind turbines are an eyesore, however, this is more of a personal preference.
5. Location limitations
In order for wind turbines to be economically viable, they need to be installed in a place where they will produce enough electricity. Wind farms are best suited for coastal areas, the tops of hills, and open planes – essentially anywhere with the strong, reliable wind.
Most of these suitable places tend to be in remote areas far outside of cities and towns, in more rural areas, or offshore. Because of this distance, new infrastructure, such as power lines, have to be built in order to connect a wind farm to the power grid.
This can be costly and may cause some harm to the surrounding environment (i.e by tearing down trees to make way for power lines).
Is Wind an energy?
The terms “wind energy” and “wind power” both describe the process by which the wind is used to generate mechanical power or electricity. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity.
What is wind and wind energy?
Wind energy, or wind power, is created using a wind turbine, a device that channels the power of the wind to generate electricity. The wind blows the blades of the turbine, which are attached to a rotor. The rotor then spins a generator to create electricity.
What is wind energy in simple words?
Wind power or wind energy describes the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power.
What are 5 advantages of wind energy?
Advantages of Wind Power
- Wind power is cost-effective.
- Wind creates jobs
- Wind enables U.S. industry growth and U.S. competitiveness
- It’s a clean fuel source.
- Wind is a domestic source of energy.
- It’s sustainable.
- Wind turbines can be built on existing farms or ranches.
What are the 3 types of wind energy?
There are generally speaking three main types of wind turbines: utility-scale, offshore wind, and distributed, or “small” wind.
What are examples of wind energy?
Examples of Wind Energy:
- Wind Farms. Wind farms are stretches of open land that often see very high winds.
- Home Energy Solutions Wind turbine technology has become cheap enough and effective enough that chain retail stores are even selling home turbine kits at affordable prices.
Why is wind energy the best?
The wind is a renewable energy source. Overall, using wind to produce energy has fewer effects on the environment than many other energy sources. Wind turbines may also reduce the amount of electricity generation from fossil fuels, which results in lower total air pollution and carbon dioxide emissions.
What do we use wind energy for?
Humans use this wind flow, or motion energy, for many purposes: sailing, flying a kite, and even generating electricity. The terms “wind energy” and “wind power” both describe the process by which the wind is used to generate mechanical power or electricity.
What are 3 disadvantages of wind energy?
Some of the main disadvantages of wind energy include unpredictability, it is a threat to wildlife, it creates low-level noise, they aren’t aesthetically pleasing, and there are limited locations suitable for wind turbines.
What causes wind energy?
Energy from moving air. The wind is caused by uneven heating of the earth’s surface by the sun. Because the earth’s surface is made up of different types of land and water, it absorbs the sun’s heat at different rates.
How wind energy is created?
Wind turbines use blades to collect the wind’s kinetic energy. Wind flows over the blades creating lift (similar to the effect on airplane wings), which causes the blades to turn. The blades are connected to a drive shaft that turns an electric generator, which produces (generates) electricity.
Where is wind energy from?
The five states with the most electricity generation from wind in 2020 were Texas, Iowa, Oklahoma, Kansas, and Illinois. These states combined produced about 58% of total U.S. wind electricity generation in 2020.
What are 3 facts about wind energy?
Interesting Facts About Wind Energy
- Wind energy was first developed with windmills in 200 BC in Persia and China.
- Wind energy was then used for hundreds of years to pump water and crush grain.
- The first modern turbine was built in Vermont in the 1940s.
- Turbine towers normally stand over 328 ft tall.
How efficient is wind power?
Wind turbines are 20% to 40% efficient at converting wind into energy.
Why is wind energy better than solar?
Wind is a more efficient power source than solar. Compared to solar panels, wind turbines release less CO2 to the atmosphere, consume less energy, and produce more energy overall. In fact, one wind turbine can generate the same amount of electricity per kWh as about 48,704 solar panels.
How sustainable is wind energy?
Wind power is sustainable because it is an energy source that does not create waste or cause carbon emissions, soot, smog, acid rain or global warming. Alongside solar and waste to fuels, wind power is among the cleanest and most sustainable energy sources we can use.
Does wind energy use the sun?
Wind energy is actually a byproduct of the sun. The sun’s uneven heating of the atmosphere, the earth’s irregular surfaces (mountains and valleys), and the planet’s revolution around the sun all combine to create wind.
What is cheaper solar or wind?
According to the latest from Lazard, which has been tracking energy costs for years, wind power was 71% cheaper in 2020 than in 2009 and the cost of solar energy dropped by 90%. In many cases, getting energy from new wind turbines and solar panels is now cheaper than getting energy from existing coal and gas plants.
Is wind energy better than geothermal?
It is known that geothermal energy has many advantages compared with solar and wind systems. These advantages include weather proof, base load, great stability, and high thermal efficiency. The total installed capacity of geothermal electricity, however, is much less than solar and wind.
How long does a wind turbine last?
A good quality, modern wind turbine will generally last for 20 years, although this can be extended to 25 years or longer depending on environmental factors and the correct maintenance procedures being followed. However, the maintenance costs will increase as the structure ages.
How does wind energy affect the environment?
As with all energy supply options, wind energy can have adverse environmental impacts, including the potential to reduce, fragment, or degrade habitat for wildlife, fish, and plants. Furthermore, spinning turbine blades can pose a threat to flying wildlife like birds and bats.