What Are The Wind Spinning Things Called?
Wind turbines are large devices that convert wind energy into electrical energy. They have blades that are spun by the kinetic energy of the wind, which turns a shaft connected to a generator to produce electricity. The purpose of wind turbines is to provide an alternative, renewable source of energy by harnessing the power of the wind.
Wind turbines are also sometimes referred to as windmills or wind generators. They provide an important source of clean, renewable energy that can help reduce dependence on fossil fuels and combat climate change.
History
Windmills have been used for mechanical power for centuries, with the earliest known examples found in Persia around 500-900 AD. These early windmills were used for milling grains and pumping water [1]. The first known wind turbine used specifically for generating electricity was built in Scotland in July 1887 by Scottish professor James Blyth. His 10m tall, cloth-sailed wind turbine was used to light his holiday home in Marykirk [2].
In the late 19th century, ranches and homesteads in the American West used small windmills to pump water for cattle and crops. By 1910, wind turbine use was rapidly spreading. Small wind turbines generating electricity also became popular on farms in the 1920s and 1930s. Over 600,000 small wind turbines were in use in the United States at the outbreak of World War II [3].
How They Work
Wind turbines convert the kinetic energy in wind into mechanical power that runs a generator to produce electricity. They consist of key components like a rotor, generator, gearbox, controller, brakes, and more.
The rotor is made up of two or three propeller-like blades mounted to a hub. The kinetic energy of the wind causes the blades to rotate. The rotor connects to a main shaft which spins a generator to create electricity. Most turbines have a gearbox which converts the slow rotations of the rotor to much faster rotations to efficiently run the generator.
Wind turbines face into the wind with sensors and motors that allow the rotor and nacelle (the rotor hub, gearbox, generator etc) to turn and stay facing the wind when it changes direction. The controller monitors wind speed, generator performance and other parameters to optimize power output and prevent damage from high winds. Brakes can be applied to stop the rotor in emergencies.
The electricity from the generator goes down the tower through electrical cables to a transformer which converts it to the proper voltage for the grid. The nacelle and rotor turn on a bearing atop the tower to face the wind.
So in summary, wind turbines use the wind’s kinetic energy to spin rotors connected to generators that make electricity. Gears, controllers, brakes and other components optimize their performance and protect the turbine.
Sources:
https://www.energy.gov/eere/wind/how-do-wind-turbines-work
https://www.nationalgrid.com/stories/energy-explained/how-does-wind-turbine-work
Types
There are two basic types of wind turbines: horizontal-axis turbines and vertical-axis turbines. Horizontal-axis wind turbines have the main rotor shaft and electrical generator at the top of a tower, with the blades facing into the wind. Vertical-axis wind turbines have the main rotor shaft arranged vertically and the generator and gearbox located at the base of the tower.
Horizontal-axis wind turbines are most common today. The main rotor shaft and electrical generator are mounted at the top of a tall tower, with the blades facing into the wind. Horizontal-axis wind turbines can have between two and many tens of blades. The blades are usually made of fiberglass infused with resin — a strong, lightweight, and flexible plastic material.
Vertical-axis wind turbines have the main rotor shaft arranged vertically. Key advantages of this arrangement are that the turbine does not need to be pointed into the wind to be effective. The generator and gearbox can be placed near the ground, so the tower doesn’t need to support it, and it’s easier to service the moving parts. Vertical-axis turbines are less frequently used today.
Offshore wind turbines are increasingly being used to harness ocean winds. Offshore turbines can be larger than land-based ones and placed in areas with consistently stronger winds. Floating wind turbines are being developed for use in water depths greater than 50 meters.
Locations
Wind turbines are commonly used in areas that experience strong and consistent winds. Some of the top regions for wind power generation include:
The United States has over 60,000 wind turbines located across 41 states. The top five states for wind power generation are Texas, Iowa, Oklahoma, Kansas, and Illinois. Texas alone produces over 30% of the nation’s wind power (Source: Where wind power is harnessed – U.S. Energy Information Administration). Other top wind power producing states benefit from consistent wind resources in the Great Plains region.
China leads the world in total installed wind capacity with over 328,000 megawatts, representing over one-third of the global total. The provinces of Inner Mongolia, Xinjiang, Gansu, Hebei, and Jiangsu contain the majority of China’s wind turbines (Source: Wind power by country – Wikipedia). China’s geographic size and diverse wind resources contribute to its world-leading wind power capacity.
Germany produced over 24% of its electricity from wind in 2020, with most of its turbines located in coastal and northern regions. Germany has also pioneered offshore wind farms in the North Sea and Baltic Sea (Source: Wind Power by Country 2024 – World Population Review).
Capacity
The total installed wind power capacity in the United States was over 132,938 megawatts (MW) as of 2022, according to the American Clean Power Association (https://cleanpower.org/facts/wind-power/). This makes wind power the fourth largest source of renewable energy generation in the country after hydroelectric, biomass, and solar power. The average size of wind turbines installed has also increased dramatically over the past two decades, going from less than 1 MW on average in the 1990s to around 3 MW for turbines installed today (https://css.umich.edu/publications/factsheets/energy/wind-energy-factsheet).
The rapid growth in wind power capacity highlights the increasing competitiveness and efficiency of wind energy technology. Larger turbines are able to capture more of the wind’s kinetic energy and convert it into low-cost, emissions-free electricity. Continued technological advances and cost declines are expected to further boost wind power deployment in the coming decades.
Cost
The typical cost to build and install a wind turbine ranges from $1 million to $4 million per megawatt (MW) of generating capacity. According to WeatherGuardWind, most utility-scale wind turbines are 2-3 MW in power, so they cost between $2-4 million each. The main factors affecting wind turbine costs are the size of the turbine and the site location.
Larger, more powerful turbines that can generate more electricity cost more overall, but the cost per MW goes down with increased size and capacity. Installing turbines offshore or in complex terrain also increases costs compared to land-based installation. However, the scale of utility wind turbines makes the levelized cost per megawatt hour competitive with other energy sources like coal and natural gas.
Environmental Impact
Wind turbines provide a clean, renewable source of energy that does not produce air pollution or carbon dioxide emissions. According to the U.S. Energy Information Administration, wind turbines help reduce air pollution and emissions that contribute to climate change and global warming when they displace fossil fuel sources like coal, natural gas and oil (source).
However, wind turbines may have some negative effects on wildlife and the environment if not properly sited. Wind turbines can pose a collision risk for birds and bats, and noise and vibration from turbines may disturb wildlife habitats (source). Careful site selection, turbine design modifications, and operational strategies can help minimize wildlife impacts.
Overall, many studies have found the environmental benefits of wind energy greatly outweigh the potential wildlife concerns, as long as appropriate siting, mitigation, and monitoring procedures are implemented.
Future Outlook
The future of wind power looks bright according to projections by the U.S. Department of Energy. Their Wind Vision report shows that wind has the potential to supply 20% of U.S. electricity by 2030 and 35% by 2050. To achieve this, larger and more efficient wind turbines will need to be developed and deployed.
New turbine designs are focused on larger rotors and taller towers to access steadier, stronger winds at higher altitudes. Current turbines are limited to about 500 feet tall, but new designs allow towers up to 1,000 feet tall. Larger rotors sweeping a bigger area can also increase energy capture. GE recently introduced a 12 megawatt turbine with a rotor diameter longer than two football fields.
Floating offshore wind farms are another important area of growth, especially along U.S. coastlines which have strong offshore winds. Floating platforms allow wind farms to be installed in deeper waters further from shore. Recent innovations like vertical axis turbines may also open up new opportunities in the future.
Overall, experts predict rapid expansion of wind power generation through larger, more advanced turbines and new offshore developments. According to the DOE’s Wind Vision report, wind has the potential to be a major renewable electricity source across the U.S. by 2050.
Conclusion
In summary, wind turbines are an important source of renewable energy that harness natural wind to generate electricity. They come in various sizes and designs, like horizontal axis or vertical axis turbines, and are increasingly being used around the world to provide clean power. Though they do have some downsides like visual impact, noise, and effects on wildlife, overall wind turbines play a key role in transitioning our energy systems away from polluting fossil fuels. Their low operating costs once installed make wind energy economical over the long term. With capacity growing each year, and technology improving, wind turbines will continue providing substantial amounts of electricity in the renewable energy mix of the future. Their ability to generate power with no emissions or pollution makes them a sustainable solution that helps combat climate change. Wind power still has room to expand its contribution, and can help nations meet their carbon reduction targets.
