What Is The Energy Process By Wind?

Wind energy refers to the process of harnessing the natural power of wind and converting it into electricity. People have been using wind power for thousands of years to propel boats, grind grain, and pump water. Today, wind energy is captured by modern wind turbines and used to generate clean, renewable electricity.

The history of harnessing wind power goes back over 3,000 years to the use of sailboats on the Nile River. The first known windmills were built in Sistan, Afghanistan around the 7th century AD. These early windmills were used to grind grain. Wind-powered pumps first appeared in the United States in the 1850s followed by electricity generating wind turbines in the late 1880s.

For most of history, wind energy was primarily used for mechanical work like pumping water or grinding grain. The modern development of wind turbines to generate electricity dates back to the 1970s with the 1973 oil crisis. Since then, technology improvements and government incentives have made wind power the fastest growing source of renewable energy in the world.

How Wind Turbines Work

Wind turbines convert the kinetic energy in wind into mechanical power to generate electricity. The main components of a wind turbine are:

Blades – Most modern wind turbines have three blades that face into the wind. The wind blows over the blades, creating lift that rotates the blades around a rotor.

Rotor – The blades and hub together form the rotor. The rotor attaches to the main shaft, which turns a generator to produce electricity.

Nacelle – The nacelle sits atop the tower and contains the main mechanical components such as the drive train, gearbox, generator, and brake.

Tower – Towers support the structure and raise the rotor to greater heights where wind speeds are higher.

As the wind blows over the blades, the lift force causes the blades and rotor to spin. The rotor connects to a main shaft, which turns inside the nacelle. The spinning shaft turns a series of gears in a gearbox, increasing the rotation speed. The gearbox connects to a generator that converts the mechanical rotation into electrical energy using electromagnetic induction.

The electricity is then sent down the tower and transmitted via underground cables to electrical substations and distribution lines, where it can be used in homes, businesses, and by utilities.

Wind Energy Production

Wind power has experienced rapid growth over the past decade, establishing itself as one of the most important renewable energy sources globally. In 2021, the worldwide installed capacity of wind power was around 837 gigawatts (GW). This accounts for approximately 7% of global electricity demand.

Many regions around the world are investing heavily in wind power. For example, the European Union currently meets around 15% of its electricity demand with wind energy. Major markets like China, the United States, Germany, India and Spain account for most of the installed capacity.

Projections estimate that by 2027, global wind power capacity will reach nearly 1,400 GW. Long term scenarios from the International Renewable Energy Agency (IRENA) forecast installed wind capacity reaching around 2,110 GW by 2030. This would supply up to 18% of global electricity demand.

Offshore wind capacity is also expected to expand substantially, from around 35 GW today to over 234 GW by 2030. The growth in offshore wind will be driven by untapped potential, technology improvements and declining costs.

With supportive government policies, advancing technologies and cost competitiveness with fossil fuels, wind power is poised to be a key driver in the global transition to renewable energy.

Advantages of Wind Power

Wind power offers several key advantages that make it an appealing energy source:

Renewable and endless supply – Wind is plentiful and won’t run out unlike finite fossil fuels. Winds are constantly replenished through natural processes.

Low operating costs – Once installed, the fuel is free. Minimal costs include maintenance and operations only.

No air or water pollution – Wind turbines produce energy without emitting greenhouse gasses or causing pollution. This makes wind a clean energy source.

Disadvantages of Wind Power

While wind energy offers many benefits, there are some potential downsides to consider:

High Upfront Costs

Constructing wind turbines and wind farms requires a significant initial investment. The average upfront cost of constructing a new wind farm is around $1.3 million per megawatt of capacity. The high upfront costs can deter investment in wind projects.

Intermittent Power Source

The availability of wind is not constant and can be intermittent. Wind speeds vary based on location, time of day, season and weather patterns. The intermittent nature of wind requires backup power sources like batteries or supplemental generation.

Potential Impacts on Wildlife

Wind turbines may potentially impact birds and bats that can be struck by turbine blades. Proper site selection, technological upgrades and curtailing turbine use during migrations can help minimize risks to wildlife.

Wind Turbine Locations

Several factors are considered when determining optimal locations for installing wind turbines. Key considerations include wind speed, frequency of windy days, and proximity to cities and power infrastructure.

Wind turbines are positioned in areas that experience average annual wind speeds of at least 15 mph (often higher). Locations with a consistent supply of wind all year or at least during high demand periods are sought. Turbines are installed at higher elevations or in wide-open sites to maximize wind exposure. Proximity to existing transmission lines, roads, and cities helps limit infrastructure costs to bring wind power to communities.

Wind farms can be sited onshore or offshore. Onshore wind turbines have lower installation and maintenance costs. However, turbines located far offshore access stronger and more consistent winds compared to land-based sites. Offshore turbines are typically built on platforms attached to the seabed or floating structures anchored to the bottom. While more expensive, offshore wind farms allow large scale projects close to major population centers. Regardless of the location, identifying sites with abundant wind resources is critical.

Wind Energy Economics

The cost to develop wind energy projects has decreased dramatically in the past decade, making it competitive with conventional sources of electricity like coal and natural gas. The main costs for a wind energy project include:

Turbines – Wind turbines account for about 75% of the total cost. The average cost for a utility-scale wind turbine is roughly $1.5 million.

Balance of System – This includes costs for roads, electrical equipment, construction, foundations, etc. It accounts for about 20% of the total cost.

Soft Costs – Permitting, financing, and legal fees make up the remaining costs.

The typical cost to build a new wind farm in the U.S. ranges from $1.3 million to $2.2 million per megawatt of capacity. However, wind power receives government subsidies and tax benefits at both the federal and state levels that help offset project costs. These incentives include:

Production Tax Credit (PTC) – A federal tax credit providing 2.3 cents per kilowatt-hour of electricity generated by utility-scale wind projects. It has spurred over $143 billion in private investment since 1993.

Investment Tax Credit (ITC) – Allows wind developers to reduce their federal taxes by 26% of qualified capital costs. Can be claimed in lieu of the PTC.

Cash grants – The Section 1603 grant program has provided over $23 billion to renewable energy developers.

Thanks to these financial incentives, wind power is increasingly cost-competitive with fossil fuel sources. The levelized cost of wind power ranges from $28 to $54 per megawatt-hour, on par with the cost of new natural gas plants.

Wind Power and the Environment

Compared to fossil fuel power plants, wind energy produces significantly lower carbon emissions which helps combat climate change.

Wind turbines do not release any emissions during operation. And the overall lifecycle emissions are much lower than coal, natural gas, and oil power plants. According to the National Renewable Energy Laboratory (NREL), wind power results in a 97% reduction in CO2 emissions from fossil fuels.

However, wind turbines can negatively impact wildlife, especially birds and bats that collide with the spinning blades. This has raised concerns among environmental groups.

Solutions to reduce wildlife impacts include:

• Proper siting of wind farms away from major bird migratory routes and bat hibernation caves.
• New blade designs and textures that make them more visible.
• Operating turbines at low speeds during key migration times.
• Deterrent and detection systems using sounds and lights.

Overall, with proper siting and wildlife impact mitigation, wind power can provide clean renewable electricity with minimal environmental footprint.

Future of Wind Energy

The future looks bright for wind energy, with major technology improvements on the horizon that will increase efficiency and bring down costs even further. Larger and more advanced wind turbines are being developed that can operate in lower wind speed areas and generate even more electricity.

Offshore wind is also expected to see massive growth, as floating wind turbines can access the immense wind resources available over deep waters. According to the International Energy Agency (IEA), the capacity of offshore wind farms worldwide is projected to increase 15-fold by 2040.

Overall, wind power is expected to continue growing rapidly in the coming decades and provide 20% or more of global electricity by 2050. With its falling prices and environmental benefits, wind energy is poised for long-term viability as a major renewable electricity source.

Conclusion

Wind energy offers a renewable and clean energy source that can play an important role in reducing our dependence on fossil fuels and mitigating climate change. This article provided an overview of how wind turbines capture kinetic energy from the wind and convert it into electricity through a generator. We looked at the many advantages of wind power, like its abundant supply, low operating costs, and lack of air and water pollution. There are some limitations too, such as intermittency, land use impacts, and effects on wildlife. But with thoughtful siting and continued technological advances, many of these disadvantages can be reduced.

With the falling prices of wind turbines and steady technological improvements, wind energy is poised to keep growing as part of the global shift to renewable energy. Wind already provides a substantial portion of electricity generation in many countries around the world. With increased government policy support, research funding, and public engagement, wind can become an even larger part of our energy mix. Harnessing power from the wind will be an important part of building a clean energy future and mitigating the worst impacts of climate change.