Bats pay a heavy price with wind turbines.
Mario Cea Sanchez / VWPic / SIPA
Tens if not hundreds of thousands of bats die each year from wind turbines.
A new device to try to reduce the mortality of bats is being tested in a park in Morbihan.
It makes it possible to measure bat activity in real time and to reduce or stop turbine activity in real time.
Like many animal species, bats are endangered.
According to a report from the National Biodiversity Office (ONB), their population has decreased by nearly 40% in ten years in France.
And as if humans, raptors and parasites were not enough, bats have been facing a deadly enemy for several years.
These are wind farms that are developing all over the territory.
Each year, tens or even hundreds of thousands of bats are victims of wind turbines.
Their death can occur after a collision with the blades of wind turbines.
But small mammals are also decimated by the change in air pressure caused by wind turbines, a phenomenon called barotrauma, which causes their lungs to implode.
Building permit canceled due to bats
While the Government wants to step up on renewable energies, the impact of wind turbines on biodiversity is the subject of great vigilance.
Since 2011, wind farms have been subject to the regime for installations classified for the protection of the environment (IPCE).
Before any construction, an operator must therefore ensure that his park will not alter biodiversity too much and threaten the species present.
On July 30, the administrative court annulled a decree of November 20, 2017 which authorized the construction of a wind farm near Ploërmel (Morbihan) because of a high risk of collision for the sixteen species of bats. identified on site.
A rare decision that makes environmentalist associations believe that things are going in the right direction.
"There is indeed the best in the protection of bats but there is still enormous progress to be made", underlines Thomas Le Campion, researcher at the Breton Mammalogical Group (GMB).
A new wind turbine clamping device
To protect bats, all species of which are protected in France, measures are already in place.
In certain wind farms where high mortality has been observed, wind turbine restraints are therefore in effect.
For several hours at night, the turbines stop working to let the bats go about their business.
Located to the east of Morbihan, the Saint-Congard wind farm, operated by the German group BayWa re, is already affected by these clamping measures.
Since May, he has been experimenting with a new device, called ProBat.
Designed by the Hérault company Sense Of Life, it should make it possible to better refine the clamping thanks to artificial intelligence.
"Microphones installed on the nacelles will record live the ultrasound emitted by bats," explains Caroline Cosnard of the company Sense Of Life.
An algorithm will then analyze them and determine the frequency of passages.
If the activity is too dense, the turbine will slow down or stop automatically ”.
Reduce the impact and maintain the park's activity
In addition to the environmental aspect, the system also has the advantage for the operator of maintaining the activity of his park.
"This limits the frequency and duration of shutdowns", indicates Caroline Cosnard, specifying that the tool also makes it possible "to collect considerable data on species".
Thomas Le Campion is more reserved about the effectiveness of this device.
"The first tests show that it did not drastically reduce the mortality of the bats", he assures.
In particular, he points to “gray areas” which do not allow the machine to detect all the bats present near the wind turbines.
While the device tested on the Saint-Congard wind farm is deemed reliable by the authorities and operators, it could however be deployed on other wind farms in the coming months.
"This test carried out here should make it possible to nourish the reflections for the projects of tomorrow", assures the prefect of Morbihan Patrice Faure.
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