Wind energy and nature conservation: a green-green dilemma

Being both an environmentalist and a climate activist, it took me a long time to find a satisfying position about wind farms. In this blog post, I want to share with you some thoughts on the topic. On one hand, I studied biology and I used to be a nature consultant working on the impact of wind turbines on bats. On the other hand, I joined the climate movement in July 2019 and started supporting a local group of Scientists for Future. In summary, I am both very aware and worried about the climate crisis and the biodiversity crisis.

Wind farms constitute an essential tool to get away from fossil fuels and decarbonise the electronic grids. The price of wind energy is already cheaper than other sources of energy. The dimensions and energy production of wind farms keep on pushing new limits. Some turbines are being repowered and offshore parks are being constructed. This source of energy is booming and it is just the beginning.

As an essential climate solution, wind farms unfortunately have the drawback that they also inadvertently kill birds and – what is often unknown – bats. An estimated number of 250.000 bats are killed by wind farms per year only for Germany. These casualties are often compared to other threats to wildlife like cats and window glasses to name but a few. Such mathematical comparisons ignore completely that different species of birds and bats are affected differently by these threats. On one hand, cats and window glasses often affect species with bigger populations. On the other hand, wind farms affect high-flying species with critical conservation status like the red kite (Milvus migrans) or migratory bat species like the Nathusius’ Pipistrelle (Pipistrellus nathusii) or the Common Noctule (Nyctalus noctula). Wind parks located in migration corridors like in Germany can have a dramatic impact on populations from individuals born in other countries. An additional threat to bats is especially problematic considering that bats generally have only one offspring per year. Furthermore, it is not because one threat affects fewer individuals that we should not tackle this threat.


Nathusius’ Pipistrelle killed by a wind turbine somewhere in Germany © Marcus Fritze.

One thing that I found especially important here: we are now building a better world for humans and nature, not just a less bad world. That is why we should all strive to switch from fossil fuels to renewable energy without adding an additional burden on wildlife. We should all push for wind farms that have reduced or no impact by promoting solutions such as:

• Building wind farms in areas of low conservation interest
• Paint wind turbines to increase their visibility
• Prevent turbine blades from turning at low wind speeds (“feathering”) or slow rotation
• Increase the wind speed at which turbines become operational (“cut-in speed”)
• Curtailing during migration seasons that see bats and birds flying higher and in bigger numbers
• Deter bats from turbines using ultrasounds

As we can see, different solutions exist and some are even applied. In Germany, new or repowered wind farms automatically have cut-in speed. The problem is that many older wind farms (ca. 75% of wind farms in Germany) do not have this conservation measure.

Due to the increase of goals for the deployment of renewable energy, there is a higher pressure to find suitable areas for the installation of wind farms. While wind farms were previously installed in agricultural areas with lower biodiversity, some turbines are now installed in sensible areas like forests or conservation areas. This new situation increases the green-green dilemma between climate and nature protection. 

Wind farms are a great solution to tackle the climate crisis but should not be given a “free-out-of-jail card” by ignoring birds and bat casualties. Solutions to limit/reduce casualties exist and should be applied and researched more. A crucial aspect is to bring all actors to the table and find trade-offs eventually thanks to mediation. We should all strive to build this better world where we tackle the climate crisis without accelerating the nature crisis at the same time.

Acknowledgements

This idea of a “better world, not less bad” comes from the book “How to be a climate optimist” by Chris Turner. I thank Marcus Fritze for the photo and providing elements about the situation in Germany about how to improve the text.