How frequently do bird strikes occur at wind farms? It’s difficult to say for sure.

Estimates vary wildly. Some suggest collisions between birds and wind turbines result in tens of thousands of deaths every year in the US and Europe. Others suggest the figures are much lower.

Either way, it's clear that bird collisions are a common problem at wind farms. And this presents an ethical dilemma for environmentally-conscious operators.

In this article, we examine some of the key considerations that could help you reduce bird collisions on your wind farm, maintain operational efficiency, and protect vulnerable species.

How to Reduce Bird Strikes on Wind Farms

1. Conduct Environmental Impact Assessments

When establishing a new site, it’s critical to assess the impact of your wind farm on the surrounding environment. Understanding bird behaviour is a key component of obtaining a permit to build a wind farm, and often guides measures that will need to be in place during operational phases.

To do this, you must conduct an Environmental Impact Assessment (EIA).

In the past, EIAs were mainly based on human observations and supported by other technologies. But in recent years, regulators have begun to advise the use of cutting-edge radar systems to enhance the data-gathering process.

Modern radar systems gather invaluable scientific data. They provide unparalleled insight into everything from numbers to migration activity. This helps regulators reach a better-informed decision regarding processes and how best to proceed.

2. Continuous Monitoring

Radar has an equally large part to play in monitoring bird mortality during operational stages. Specifically, as a way to monitor traffic and measure the impact of your wind farm on the environment over the long term. Continuous monitoring is mandatory for many government bodies.

Bird detection radar operates autonomously in any conditions – 24/7, 365-days a year. They can be deployed at onshore or offshore wind farms and are sophisticated enough to distinguish between individual bird tracks and flocks. Once installed, they offer real-time tracking and positional data of both resident and migratory birds.

The most innovative radar systems take things a step further.

Greater operational range allows them to collect data on flocks and large birds up to 10km distant (2-3km for smaller species) in optimum conditions. They can be combined with supplementary sensory equipment, such as infra-red cameras or acoustics.

Alone, they can also provide full 3D coverage of your surroundings. This enables you to monitor everything from overnight mass migration events to individual bird movements with unprecedented precision. 

High-quality data like this helps to reduce bird mortality rates and assists wider conservation efforts. For example, recent research suggests that birds of prey are at a significantly greater risk of collision with turbines. Many of these, such as the white-tailed eagle or vulture, are protected species. Fully understanding the species and behaviour patterns is a critical step to minimise collisions.

3. Automated Turbine Shutdown

Automation, in the form of autonomous turbine shutdown, can be extremely effective at reducing bird mortality on wind farms.

The way it works is simple. Once specific parameters have been met or a pre-determined threshold has been crossed, the software automatically issues a shutdown command to your SCADA systems. For example, when a large flock of birds approaches within 1km of your wind turbines.

You can even programme some systems to match certain bird tracks to specific birds species. These tracks are identified by combining specific parameters, such as flight characteristics, speed, and weight. In Tahkoluoto, wind farm tracks can be associated with the white-tailed eagle or black-backed gull to create a signal to slow or shut the turbine(s) down.

Keeping your site ticking over is important. That's why some systems even trigger the individual shutdown of specific turbines, so you won't have your entire wind farm grinding to a halt.

Decisions are made between the regulators and the operators to identify specific parameters to work within. This may include wind direction, time of day, bird height, and even season. The goal is to keep disruption to a minimum.

Using Radar To Reduce Bird Strikes at Wind Farms

The amount of wind turbines is only going to increase as governments across the globe continue to invest in green energy initiatives. And while that’s an important step on the road to reversing climate change, it will also increase the potential for bird strikes at wind farms.

Operators have a fundamental responsibility to do everything in their power to reduce bird deaths and protect vulnerable species. Radar systems can assist them in their ongoing efforts to achieve this.

Employing these methods may not eliminate bird strikes entirely. But we’ve seen first-hand the benefits of using radar systems on wind farms.