Are Wind Turbines & Solar Panels Dangerous To Birds?

The consequences of human-fueled climate change are getting rampant and harder to ignore. Because of the pressing need to carbonize our energy grid, wind and solar power are growing exponentially worldwide.

As more and more wind turbines and solar panels dot our landscapes, people are increasingly worried about their influence on wildlife – especially birds. Bird mortalities have become the most prolific stain on the environmental record of wind turbines. Moreover, solar panels are also being scrutinized as their numbers increase.

However, fossil fuels are also massively killing birds in more ways than one.

What is the true impact of the most popular renewable energy sources on the avian population? How many birds really die from wind turbines, and are solar panels also a threat to birds?

Read on to learn more – hard facts only.

The Dangerous Wind Turbines

Wind turbines can kill or injure birds through collisions with the wind turbine parts, predominantly the rotating blades. However, it is not just the turbines that are dangerous. Related infrastructure like power lines also have their fair share in bird deaths.

There are various estimations of birds killed by wind turbines. Because so many bird deaths go unnoticed and not all can be directly counted, scientists and engineers have to make estimates based on calculations that vary from model to model.

The American Bird Conservancy now calculates that around 681,000 birds are killed by wind turbines in the US each year. In the UK, the estimated number of birds is 10,000 to 100,000 annually.

Read more: What are the biggest threats to birds (in numbers)

It is true that bird mortality from wind energy increases with each turbine we add to the landscape, but doesn’t mean that all turbines kill birds every day. Rather, these are average calculations based on the number of turbines. Unless design innovations and expert voices are included in new wind powerplant development projects, bird deaths from wind power will surely rise.

Fortunately, many wind projects and companies now hire professionals to tackle the issue of bird mortality specifically. That should decrease the number of birds that die from wind power infrastructure in the future.

How fast do wind turbines spin?

The speed of the wind turbine spinning depends on its size and the wind speed. In general, wind turbines can make 10 to 20 revolutions per minute. The speed is measured at the tip of the blade and largely depends on the blade’s size.

Smaller blades usually spin at 75 to 100 miles per hour. Larger blades reach speeds of 120, 130, and up to 150 mph. It is easy to see why birds, unfortunately enough to run into a spinning blade, don’t stand a chance.

However, the spinning of the blade itself isn’t the key to all bird kills. The location and positioning of the turbines are crucial factors in increasing (or decreasing) bird deaths from this renewable power source. Avoiding placing wind power plants on or near migration routes and resting sites greatly reduces the risk.

Also, wind turbines do not have the same impact on all birds. Some bird species are more susceptible to turbine collisions, and some populations are less capable of sustaining losses than others due to their reproductive ecology.

The Dangers of Solar Panels

Photovoltaic (PV) solar panels haven’t been thought of as a direct danger to birds because they are inert – without any moving parts. However, it turns out that they can also harm birds.

Because of the reflection, birds can mistake the surface of PV solar panels for a water body. The phenomenon is colloquially known as the “lake effect.” Waterfowl and shorebirds may hit the panels in an attempt to land on water. In other birds, the water-mimicking solar panel surface may induce drinking behavior and cause a collision because of the bird’s drive to quench their thirst.

© NPS Climate Change Response

Still, solar power plants have another, perhaps more important, way to influence bird populations. Because they require a lot of space, they can endanger open habitats and Important Bird Areas when installed on the ground, as is the case with most large-scale solar development. That is why bird conservation societies sometimes intervene to stop certain solar projects in highly sensitive locations and protected areas.

On the other hand, some birds actually benefit from the habitat modification and shelter provided by solar panels in the landscape.

Are there any ways to prevent these kinds of collisions?

Fortunately, there are very efficient ways to decrease bird deaths from both wind and solar.

Preventing Negative Effects of Wind Power On Birds

Good planning prevents collisions with wind power infrastructure and disturbing important bird habitats. Wind projects in locations like major migration routes, stopovers, and roosting sites are highly threatening for birds; accidents are basically just waiting to happen. Still, there are plenty of locations that are not problematic.

Prevention Through Planning

Consulting bird experts is essential in the process of building a safe wind power plant or other projects. The American Bird Conservancy has created a wind risk assessment map in an effort to curb collisions and other negative impacts of wind power projects. We recommend that all individuals and companies considering going into wind power consult this map (and the available experts!).

Prevention Through Design

There are also technical solutions that could help prevent collisions in different ways. For example, a small study in Norway found that painting one wind turbine blade black, reduced bird deaths by 70 percent.

The radically different turbine designs could make wind power stations much safer for birds in the future. Fine examples are these “motionless” and pole-shaped bladeless wind turbines, both still under development.

Preventing Negative Effects of Solar Power On Birds

Preventing the negative impact of solar panels includes preventing habitat disruption and destruction by solar installations, and reducing the chances of collisions with the infrastructure.

Like in the case of wind power, note that the solar infrastructure doesn’t only include the panels but also transmission lines, substations, battery storage power stations, etc.

Choose the Right Location for Your Solar Project

Choose a site that doesn’t belong to a bird migration route or a nesting area. Don’t install solar panels near or above wetlands, lakes, rivers, and other water bodies because these are often sensitive habitats, plus you increase the chance for the “lake effect.” All of this especially goes for large solar systems.

Alternatives To Ground Panels

Whenever possible, use rooftop and wall-mounted solar panels instead of ground ones. This way, you utilize already modified surfaces instead of pristine ground habitat.

© Elliott Brown

Avoid Reflective or Mirrored Solar Panels

Reflective and mirrored solar panels are a bigger risk to birds as they are more easily confused with water surfaces. Matter and non-reflective panels are a way to go. Some companies purposefully make panels with a lower risk of bird collisions.

Create a Proper Distance Between Panels

The spaces between individual panels should be either large enough for birds to move and escape easily without becoming entraped, or too small for birds to enter them. If the panels need to be installed close together, you can add bird-safe mesh or netting to prevent them from entering the gaps.

Installing deterrents

Birds shouldn’t get too comfortable hanging around the panels. Perching on solar panels attracts other birds and increases the risks of collisions or entrapment. Installing bird-safe anti-perching devices like sloping covers or visual deterrents can help discourage bird activity around the panels.

Interesting Facts

• Depsite the numbers of birds destroyed by wind turbines possibly reaching 1 million, even more are killed by domestic cats, window collisions, car collisions, and climate change-fueled extreme weather.
• Not all birds are equally prone to wind turbine accidents. Raptors and large migratory birds are especially at risk.
• Some bird species are disproportionately affected by wind turbine colisions due to thecollision likelihood combined with their small populations and low reproduction rates. The Californian Condor is one such example.
• Other forms of solar power that don’t include PV panels are not safe for birds. Concentrated solar power (CSP) technology concentrates solar rays onto a receiver using mirrors; birds and other flying animals can be attracted to the light coming from the beams and mirrors. Sadly, the extreme heat that comes with concentrating sun rays is a deadly trap for them.
• A 2012 study found that that found that wind farms result in roughly 0.27 bird fatalities per gigawatt-hour (GWh) of produced electricity, compared to 0.6 fatalities per GWh for nuclear power plants, and 9.4 fatalities per GWh for fossil-fueled power stations.
• Despite the potentially harmful effects of wind and solar on birds, all scientists and bird conservation societies agree that the combination of climate change effects and fossil fuel exploitation is still many times more harmful to bird populations than wind and solar.

Frequently Asked Questions

What kills the most birds?

Most bird lives are lost to domestic cat predation – an average 2.5 billion (range: 1.3–4.0 billion) in the US alone. Next are window glass collisions (1 billion per year in the US) and collisions with powerlines and electrocution (25.5 million plus 5.6 million).

If we look at broader reasons behind bird declines where individual losses are harder to count, habitat loss and degradation are a global number 1. Global warming-fueled super-storms also increasingly take more and more bird lives.

How many birds do wind turbines kill?

There are various estimations of wind turbine bird kills. According to the American Bird Conservancy, 681,000 birds are currently killed by wind turbines in the US each year. In the United Kingdom, the annual estimations range from 10,000 to 100,000 birds.

Unfortunately, these numbers are probably to increase because wind power is growing exponentially. On the other hand, many wind projects now hire professionals specifically to tackle the issue of bird mortality, which should decrease the number of birds that die from wind power infrastructure.

Is nesting under solar panels dangerous for birds?

It is unclear how truly dangerous it is for birds to nest under solar panels.  In theory, nesting under panels could indeed increase fire and electrocution risk, which is bad for both the birds and the solar systems.

The pest control industry keeps pushing the narrative that birds nesting under solar panels is always disastrous for solar power systems (of course, selling bird repellents is a handy side-effect of spreading this information) but without providing substantial stats. It seems that there is no hard data yet to tell us how dangerous nesting under pannels really is.

Read next: What can we do against unfair bird deaths?