Wind power is one of the fastest-growing sources of energy globally. As the world transitions to cleaner sources of energy with a smaller carbon footprint, wind and solar energy are often praised for their ability to reduce greenhouse gas emissions. However, are wind turbines bad for the environment?
Although significantly less than others, wind power also has some environmental impact. Unfortunately, every type of energy has some environmental impact, including wind energy.
For example, air pollution from fossil fuels is often called the “silent killer” because it is responsible for so many fatalities. Mountain top removal coal mining, as the name implies, has a dramatic impact on wildlife habitat and water quality. Fracking for oil and natural gas produces greenhouse gas emissions, contaminates water, and destroys wildlife habitat.
Do wind turbines pollute the environment while in operation?
No, they don’t. One environmental advantage to using renewable energy, including wind turbines and solar panels, is that they do not produce emissions or solid waste during operation and do not require water for cooling, which most fossil-fired power plants need. Also, because they do not use a fuel source, such as coal or natural gas, no fuel is extracted, and there is no spent fuel left over.
However, wind farms are visually imposing to some and do create audible noise. When wind turbines are installed near where people live or work, it can create a disturbance.
By comparison to other sources of noise such as planes, trains, and roadway traffic, the noise from wind turbines is typically minor.
To mitigate the sound issue, many governments have created sound limits for wind farms and have set back rules, so turbines are not located very close to dwellings.
Although the operation of a wind farm has little environmental impact, it is important to consider all phases of a wind farm, from planning to end-of-life. When considering the environmental impact of wind turbines, the manufacturing, transportation, installation, and decommissioning of wind farms have the largest environmental impact, not the operation.
How does pollution from wind turbines compare to fossil-fired power plants?
Sadly, fossil fuels pollute air and water and contribute to lung disease and heart disease. In fact, more than 8 million people died globally from fossil fuel pollution in 2018, according to research from Harvard University, in collaboration with the University of Birmingham, the University of Leicester, and University College London. In particular, it is exposure to particulate matter from fossil fuel emissions that are the culprit, causing an estimated 18% of deaths worldwide in 2018
Sadly, fossil fuel consumption leaves a myriad of waste in its path. For example, natural gas, petroleum, and coal require mining and drilling, which has a grave environmental impact. Also, the combustion of fossil fuels creates waste called fossil fuel combustion waste. Unfortunately, this waste can harm water quality when not properly handled.
Coal ash is an example of fossil fuel combustion waste and it contains contaminants like mercury, cadmium, and arsenic. Without proper disposal, contaminants can pollute waterways, groundwater sources, drinking water, and the air. In the EU-15, the residues from coal combustion total an estimated 59 million tonnes annually, so it is a considerable source of waste.
During operation, wind turbines do not produce waste or pollution and do not require mining for fuel, making them far greener. Wind energy also helps protect human health by preventing air and water pollution.
How much land do wind farms require?
Terrestrial wind turbines require land to operate, which can harm wildlife habitat. Direct land use is necessary for the concrete tower pad, utility substations, and new access roads.
According to a study by the National Renewable Energy Laboratory (NREL) in the U.S., direct land use for wind turbines averages about 3,000 square meters (¾ of an acre) per MW of nameplate capacity. Therefore, a 2.5 MW wind turbine requires about 7,500 square meters of land.
In addition, space is needed between wind turbines to maximise their power production. However, wind turbines make efficient use of space because much of the land surrounding wind farms can be used for other purposes, such as farming and ranching.
Is wind farm construction harmful to the environment?
Like other major construction projects, developing a wind farm does have an environmental impact, even if it enables the production of clean energy for decades. For example, constructing access roads, excavating for foundations, transporting large wind turbine towers and blades, producing concrete for wind turbine pads has an environmental impact.
When planning and constructing a wind farm, it’s helpful to consider these factors to reduce the environmental impact. For example, avoiding disruption to wetlands helps protect wildlife habitat, and adequate erosion and sediment control measures help protect soil and water quality.
It is critical to avoid impacting the soil and crops during construction because this can reduce the productivity of cropland and grazing areas. Also, it is essential for all solid and hazardous waste to be properly disposed of from project areas. In addition, conducting cultural, historical, and archaeological resource surveys can help identify archaeological sites and prevent their disruption.
Are wind turbines recyclable?
Industrial-scale wind turbines are largely recyclable and contain steel and copper primarily. Thus, these materials are widely recyclable, and there is strong market demand for them.
Most wind turbines have tubular steel towers manufactured in 65- to 100-foot segments to make them easier to manufacture and ship. The gearbox and generator on wind turbines are largely recyclable.
Still, the generator does contain rare-earth metals, and the implications of recycling rare earth metals have not been well studied.
Unfortunately, of all the components in a wind turbine, the blades are the most difficult from a waste management standpoint. Sadly, these are commonly disposed of in landfills or by incinerators. Wind turbine blades are not readily recyclable and are sometimes downcycled into low-value products.
In the long term, developing and using truly recyclable plastics would ensure that wind turbine blades are truly recyclable. NREL is researching the use of a thermoplastic resin for blades because it is more readily recyclable, requires less energy during production, and may even allow onsite manufacturing.
Because utility-scale wind turbine blades can be 107 meters (351 feet) long and are hollow, they require large trucks to transport them. However, onsite manufacturing could potentially decrease the emissions from transporting wind turbine blades long distances.
Do wind turbines kill bats and birds?
Sadly, wild bird populations are in decline globally. A recent study by American Bird Conservancy showed there are 2.9 billion fewer birds throughout the U.S. and Canada than in 1970 or a nearly 30-percent decrease in the total population.
The leading risks are climate change, habitat loss, pesticide use, and pets, but there are other factors. Although wind turbines and utility transmission lines are often identified as culprits, their impact is relatively minor compared to other sources.
For example, in the U.S., domestic cats kill 2.4 billion birds annually, and collisions with building glass and motorized vehicles kill more than 800 million each year. Researchers have conducted numerous studies to determine why wind turbines kill bats and birds.
Although it might seem minor by comparison, between 140,000 and 500,000 birds die at U.S. wind farms each year, according to estimates by the U.S. Fish and Wildlife Service. However, the exact impact varies considerably by location and region.
For example, Altamont Pass, California, contains over 5,000 older and smaller wind turbines and is located in a bird-migration corridor. Sadly, it is notorious for bird deaths, highlighting the importance of considering the impact on wildlife in the wind farm siting process.
According to the U.S. Energy Department, there is also evidence that newer wind turbines kill fewer birds than old ones because their rotor diameter has increased in size dramatically in recent years. As wind turbines get bigger, the turbine blades rotate more slowly. Also, fewer wind turbines are needed to produce the same amount of renewable energy when using larger-capacity wind turbines.
In addition, research shows that the use of monopole tubular towers instead of lattice towers for smaller wind turbines reduces bird collisions because birds cannot perch on the towers. Also, there is research in other low-cost ways to minimize bird fatalities.
In Norway, a wind farm in Smøla is known for white-tailed eagle collisions. However, a 2020 study by the Norwegian Institute for Nature Research found that fatalities were reduced by more than 70 per cent when one of the turbine blades was painted black. Research and implementation of such practices can protect avian species while ramping up wind energy production.
It is critical to remember that climate change poses an enormous threat to wildlife. Droughts, severe storms, heatwaves, rising sea levels, melting glaciers, and warming oceans create grave threats to numerous species across the globe. One of the best ways to prevent bird fatalities is to dramatically reduce greenhouse gas emissions globally.
Greater renewable energy deployment is an excellent way to reduce emissions to slow climate change. As the world transitions to cleaner sources of energy, wind energy provides a viable alternative to burning fossil fuels because it is cost-competitive and produces no emissions.
How can we reduce the impact of wind farms on the environment?
There are numerous ways to mitigate the ecological impacts of wind farms. Opportunities exist throughout the lifecycle of wind farms to protect the environment and conserve resources.
Wind Turbine Manufacturing
Currently, the design life of a wind turbine is about twenty years, but they can sometimes be in operation longer. Wind turbine manufacturers can develop wind turbines with a longer lifespan, reducing the need to construct new wind farms and reducing waste.
Wind Farm Management
Across Europe, 28% of installed wind turbine capacity is 15 years or older. That means many projects will reach the end of the design lifespan soon. As a result, many wind farm operators are making various decisions that impact the environment.
For example, after about 20 years in operation, they are often faced with the decision to either: extend the life of the wind farm, repower it, or decommission it. Repowering a wind farm typically entails replacing wind turbines with newer units, whereas refurbishing entails updating some components on the wind turbines.
Although there are many considerations, including financial, the first two options extend the lifespan of the wind farm. Because the site has already been impacted by creating wind turbine pads, access roads, and utility substations, it is often logical from an ecological standpoint to keep the wind farm operating.
Likewise, actions can be taken to prevent bird and bat fatalities. Researching low-cost methods such as painting one blade black can protect avian species.
Decomissioning Wind Energy Projects
For projects that are decommissioned, doing so in the most environmentally-friendly manner is critical. Unfortunately, because relatively few wind farms have been decommissioned, there is a lack of standard protocol to reduce the environmental impact, so more work is needed in this area.
Despite much attention going into planning and constructing a wind farm, less emphasis has been put on decommissioning wind farms. This will become increasingly important as more and more wind farms are decommissioned. One way to make wind farms more sustainable is to ensure that as many components as possible are recycled or reusable.
Although many parts of a wind turbine are recyclable, the wind turbine blades are difficult and often costly to recycle. One of the best ways to prevent wind turbine blades from going to landfills is to reuse them for pedestrian bridges, bike shelters, or utility lines.