Wind farms are one of the most powerful sources of sustainable energy. By 2050, the global energy sector aims for 90% of all electricity to come from renewable sources, with solar and wind responsible for up to 70% of electricity generation.
There’s increasing urgency to harness wind power across the world. China, the U.S., and the UK are leading new wind power capacity planning. And experts suggest that wind power growth must triple in the next decade to avoid the worst impacts of climate change. That’s an average of 180 GW of new wind energy each year.
However, while wind energy has proven to be a crucial, sustainable resource, wind farms can also have a damaging environmental impact on birds.
Thankfully, technology is here to help. In this ebook, you’ll discover five solutions that can mitigate the impact your wind farm has on bird populations.
Collision risks of wind turbine blades
Habitat loss and population displacement over time
Poorly sited wind farms and infrastructure
Wind farms have both an immediate and cumulative impact on bird populations. The most obvious immediate impact is bird deaths caused by collisions. Birds can collide with turbine blades or associated infrastructure, such as overhead powerlines. The likelihood of this depends on factors like bird species, season, time of day, noise, and even wind speed or temperature.
But as wind farm expansion continues, organisations are realising the true impact of wind farms on wider biodiversity too.
It’s not just collisions that affect birds. Wind farms also alter and disrupt their habitat. This fundamentally changes bird populations. It causes biodiversity loss and displaces certain bird species.
Biodiversity loss is a decline in the number, genetic variability, and variety of species of biological communities in an area. It breaks down ecosystems in the wind farm location. This can extend even further in the case of migratory birds.
The causes of biodiversity loss:
These factors create life-altering changes for birds, which leads to a decrease in bird population over time.
500,000+ Approx. no. of bird deaths caused by wind turbines each year. American Bird Conservancy
Before we explore the technology that can reduce bird mortality, it’s important to understand the control factors of wind farm planning and operation that can affect bird populations.
According to the International Union for Conservation of Nature (IUCN), preventive action is one of the key methods of mitigating bird mortality at wind farms.
“Preventive actions are preferable from an economic, social, and ecological perspective for lenders, regulators, and other stakeholders. Compared to avoidance and minimisation, restoration and offset measures tend to have less certainty of success and come at a higher cost to the developer.”
So, what are some of the preventive actions that developers, stakeholders, and operators can take, and why are they important?
Conducting a risk assessment of the wind farm site at the early planning stage of the project will mitigate biodiversity impacts across a variety of sectors. Developers should choose a site that allows them to avoid future risks from the start.
Ideally, wind farm operators shouldn’t rely on avian detection and monitoring solutions alone to mitigate their impact on birds. Put simply, environmental considerations should come first, and technology follows.
Wind farm construction can have a significant impact on bird populations. In some cases, bird population numbers struggle to recover. One study found that UK-based wind farms had a measurable impact on curlew and snipe bird populations during the construction phase. These wind farms had a high overlap between the turbine footprint and the surveyed area.
To avoid this, developers should consult, monitor, and plan for the impacts of construction to avoid disrupting natural bird behaviour at wind farm sites.
When a wind farm is fully operational, bird behaviour mustn’t become an afterthought. To minimise bird deaths, wind farm operators need to monitor how their wind farm impacts bird populations. And to do this, they need the latest technology and data tracking software.
With the right systems, they can get a clearer picture of how many birds are colliding with blades at their farm, and whether mitigation methods are working or not.
With these considerations in mind, what technology is currently available to help wind farm operators reduce bird mortality?
We’ve created a comprehensive overview of the detection, monitoring, deterrent, and mitigation solutions in the wind farm landscape today.
Cameras help to reduce bird mortality by monitoring birds at the wind farm site. They’re a cost-effective solution that is more suitable for smaller wind farms. This is because they perform better with a limited number of turbines.
Cameras use imaging to provide the best coverage. However, cameras are more proficient at collision monitoring. This is due to closer proximity and the number of angles they capture, helping wind farm operators identify the rate at which they occur. This is opposed to radar solutions, which can be challenged by clutter and resonance.
However, the sophistication of camera technology can still leave a lot to be desired for wind farms. Significant developments in camera technology, such as infrared and thermal imaging can be used to detect bird species. But they aren’t widely used as they can’t perform well in adverse weather conditions.
Bird detection radars are systems that detect and track birds automatically. You can use them during the pre-construction and operational phases of the site to plan, track risks, and monitor bird activity over time.
For wind farm operators, radars are a powerful tool for conducting risk analysis and environmental impact assessments (EIAs). Over time, the technology gathers scientific data on bird movements within the area in great detail.
Radars can detect and log hundreds of birds at once, including their size, speed, direction, and flight path. This makes them a solution for wind farm sites that operate at a large scale, in addition to their superior range, spanning kilometres of a wide area. Avian radars can also be integrated with turbine shutdown functionality, providing greater accuracy for operators to reduce downtime.
Cameras and radars aren’t an either/or solution.
In fact, they work well together.
You can integrate these technologies to provide a comprehensive level of monitoring and mitigation. For example, if you need the close collision monitoring of cameras but want the range capabilities of avian radars, an experienced radar system provider can help you build a system that combines the two. All using smart software that integrates the data you need into one place. You can get the exact technology you need to improve the visibility of birds on your site, control risks, and plan ahead for the future.
Every wind farm project is different. Depending on the site location, landscape, and infrastructure, it’s likely the requirements of your bird detection solutions will change. The needs of offshore and onshore wind farm sites will vary widely, for example, and everything from weather conditions to bird migratory patterns will present different challenges.
A recent study carried out by one of our clients, The Norwegian Institute for Nature Research (NINA), revealed how painting turbine blades black can help to deter birds from colliding with wind turbine blades.
This is achieved by reducing motion smear. Motion smear is a visual phenomenon that occurs when an object is moving so fast it appears to the eye like a near-invisible blur. Researchers suspected that this phenomenon made it harder for birds to see wind turbine blades, especially the tips, increasing the chances of collision. So, NINA implemented a solution.
The research institute painted a single blade of four turbines black and left four unpainted. Bird strikes were reduced by 70%. More testing is needed to prove the effectiveness of this method conclusively, but the initial results are certainly promising.
Acoustic deterrents are sometimes used at wind farms but aren’t common or validated as a well-established deterrent. They can mimic the sounds of certain bird species or emit noises to keep them away. However, they must be triggered by either cameras or radars to work effectively, and acoustics are more commonly used at airports and runways.
Also, acoustics solutions aren’t easily portable, and don’t actively repel birds that come within close proximity. This creates significant operational limitations for wind farms, especially in remote locations where operators rely on technology to keep birds away. In some fringe cases, acoustic integrations could be suitable for small wind farms with data on local bird species.
Targets specific species of birds
Turbine shutdown is the process of halting wind turbines to reduce the risk of bird mortality. You can use this method alongside your detection and monitoring solutions. For example, you can integrate turbine shutdown functionality with avian radar solutions.
When you use turbine shutdown alongside radar, the radar uses real-time information to create a signal. This information is collected beforehand to create a ruling for the mechanism. This means your wind turbines only shut down for the exact amount of time they have to, reducing the overall impact on shutdown times, energy production, and costs.
Without this, many wind farm operators struggle with ‘blanket shutdowns’. They’re forced to shut down for long periods to avoid bird mortality. This can be an extremely costly and disruptive procedure, so integration with a detection and monitoring solution is essential to maximise its effectiveness.
The impact of wind farms on birds can be far greater than just reducing population. Birds represent an important player in the environment’s ecosystem.
For example, birds shape plant life by dispersing seeds in their droppings and pollinating plants. Some bird species are a particular area's natural predators and help to control pests. This makes them a key priority for wind farm stakeholders, developers, and operators looking to reduce environmental impact.
Wind farms remain one of the most important sources of sustainable energy and are only set to become more prevalent in years to come. With a combination of effective monitoring, technology, and software, you’ll be well-equipped to reduce bird mortality at your wind farm site.
Robin Radar Systems
Laan van Waalhaven 355
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