Wind power has been around for thousands of years, and the Earth's free and abundant winds were and are used for navigation, grinding grain, and pumping water. Only recently has humanity begun to harness this energy to generate electricity, and it already accounts for a substantial and growing proportion of our electricity supply. At present, 6.6% of the world's electricity is supplied by wind power, 7.3% of our electricity is supplied by wind power, and 23.1% of Spain's electricity is supplied by wind power.
Wind has many benefits: it's a relatively simple renewable energy source that, once used, doesn't require a lot of maintenance and doesn't pollute the air and water. Most importantly, in a world where we are all beginning to feel the direct effects of the climate crisis, wind turbines generate electricity without emitting greenhouse gases.
However, this clean energy comes with its own challenges as well as some drawbacks, the two biggest being its environmental impact and the inherent variability of the wind. Although there are some measures to alleviate these shortcomings, they certainly should not be ignored or trivialized. Economically, wind energy is expensive up front, and indeed most forms of energy are, and fossil fuel plants require more maintenance, which means higher operating costs.
01 Advantages of wind energy
The most significant advantage of wind energy is that it produces electricity without polluting the air or water or adding greenhouse gases to the atmosphere. But it also has some other unique environmental and economic benefits.
1. Environmental benefits
Wind energy does not cause climate change. While there are energy costs associated with manufacturing and transporting turbines, a study of the life cycle of wind turbines found that their carbon footprint can pay off in carbon dioxide savings during just six months of operation. In 2019, generating electricity from wind prevented the equivalent of 43 million cars from emitting carbon dioxide.
1) Renewable energy. Wind energy is never in short supply and never runs out, so wind energy is a renewable, sustainable energy supply. That energy doesn't have to be dug out of the ground or transported by train or truck, which requires extra energy and emissions and adds to the cost of plants that burn fossil fuels. And new wind turbines are getting more efficient.
2) Zero emissions. Once located and installed, wind turbines or wind farms produce no wastewater or emissions. No scrubbing of chimneys, no handling, handling, dumping or burying of toxic materials.
3) It doesn't need to be near a water source. Water is not needed to run a wind turbine, nor is it used to cool machines or for any other purpose, so wind turbines do not need to be built near a waterway or connected to a water source.
2. Economic benefits
1) Low operating costs. Once installed, wind turbines are cheap to run.
2) Cost without resources. Wind energy is free, so the energy cost is zero. These cost savings mean it is cheaper than the coal plants that are widely used today. A 2016 financial study found that unsubsidized wind projects cost between $32 and $62 per megawatt-hour. Coal power costs between $57 and $148 per megawatt hour. In a world dealing with climate change, costs are expected to fall as wind intensifies, which could mean more electricity from wind in coming years.
3) Rural areas also benefit. Wind energy facilities also benefit the rural economy, as most wind farms are located in rural areas with low population.
4) Wind power is affordable and may require fewer subsidies. All large energy delivery systems are subsidized by the government, including coal plants and wind farms. But the fossil fuel industry is likely to receive higher grants and tax breaks than the renewable energy industry, depending on which factors are taken into account. Should artificially low mining costs on public lands count as subsidies? Environmental and financial analysts are divided.
5) Wind turbines do not cause air pollution and associated health hazards. Coal-fired power plants have been shown to have a negative impact on people's health, which can lead to medical expenses. These are not generally considered the "costs" of producing coal-fired electricity. Whether this is an economic impact or a human health impact, or both, it is worth considering as a cost or cost saving for wind energy.
6) Wind energy is flexible and can achieve energy system independence. Unlike fossil fuels, which typically require a centralized power plant to generate electricity efficiently, wind energy is flexible in scale and space. (Even home oil-fired generators are used in emergencies, but they are inefficient and pollute the local air.)
7) The size and number of wind turbines can vary depending on location and energy demand. When one thinks of wind power, one imagines wind farms with hundreds of turbines, but there are also small and medium-sized turbines working individually, or in pairs, or in threes to deliver so-called distributed electricity to those in need. In the United States, the Department of Energy reports that there are more than 85,000 of these small turbines, which could provide 1,145 megawatts of power.
8) Scalability. Small turbines can power homes, ranches, farms or buildings; Larger turbines can be used for industrial or community needs.
02 Disadvantages of wind energy
Wind power faces some significant challenges, most notably the ecological impact on birds and bats. Opponents also argue that the noise generated by the turbines will affect the quality of life of nearby residents.
1. Reliability problems
1) Wind reliability can vary. Although turbines may produce energy 90 percent of the time, they may not use 100 percent of their installed capacity. The average installed capacity is 35 percent.
2) Unpredictability. Low or no wind will shut down the wind turbine, and too much wind (protecting the machine) will shut down. Too much wind may cause the turbine to catch fire. During this time, maintaining the normal flow of electricity requires storing wind energy from batteries or other sources.
2. Noise and visual pollution
1) Noise pollution. Wind turbines can produce noisy sounds in the 40-60 decibels range (equivalent to a medium-sized window AC unit), which obviously disturbs people who live near even smaller turbines, but the data on the health effects of wind turbine noise are inconclusive.
2) Affect wildlife. Noise from wind turbines is also likely to affect wildlife, especially birds and bats, but also other animals that use vocalizations to communicate.
3) Aesthetic issues. Some people think wind turbines are unsightly and don't like to see them on land or water.
4) Flickering shadows. It's a phenomenon caused by the spinning blades of a wind turbine pairing with the sun on the low horizon. This casts a moving shadow, thought to be a flickering leaf movement. While it tends to occur only in specific, time-limited circumstances, it can be disorienting and unsettling for people who live near turbines. The shadow flicker effect can be calculated and mitigated. Smaller turbines generally do not have as much of a problem with shadow flicker because of their shorter blades, so this is mainly an issue for larger turbines.
3. Ecological impact
1) Bird collision. Wind turbines are responsible for a large number of bird deaths. One of the most famous studies of bird collision deaths at wind farms found that wind turbines kill between 140,000 and 328,000 birds a year in the continental United States. There are solutions (such as building wind farms away from large numbers of these animals, or installing radar to turn off turbines when birds or bats approach), but it is unclear whether they will work. Bladeless turbines may be another solution to this major problem.
2) Impacts on local ecosystems. Wind farms, like any other large-scale industrial development, can have an impact on local ecosystems. While much of the land of the wind farm can be used as habitat by animals, there are still repairs to roads and other infrastructure, especially power lines, which can have a negative impact on wildlife in the area.
3) Potential impact. The ecological effects of wind farms are unclear and may have unintended consequences. Studies in India, for example, have found fewer birds of prey and more lizards near wind farms, upsetting the local balance of predators and prey.