The French should consume more electricity by 2050. To meet this demand, it will be necessary to strongly develop renewable energies, including onshore and offshore wind, calculates the operator of the RTE electricity network.
But the rise of wind farms arouses opposition for aesthetic issues, noise or for the potential impact on animals, birds and bats on land, or on marine fauna during the construction phase.
Wind farms have "impacts on biodiversity that we must control", acknowledged Nicolas Wolff, president of France Energie Eolienne (FFE) which brings together the sector in France, during a seminar organized Wednesday and Thursday by the League of bird protection (LPO) in Paris.
A first response is to "plan the development of wind power so that sites of importance for birds and bats are preserved", pleads the president of the LPO, Allain Bougrain-Dubourg.
Migration stops
"Wind turbines are very heterogeneous sources of mortality" depending on where they are located, explained to AFP Geoffroy Marx, responsible for renewable energy and biodiversity programs at the LPO.
An onshore wind farm seen above the clouds, near Chatellerault (central France) on November 10, 2021 Guillaume SOUVANT AFP
The government recently instructed the prefects to map areas suitable for the installation of wind turbines, with a first return expected at the end of November.
Regarding migratory birds, "it is problematic when wind turbines are installed near migration staging areas", even more than in migration corridors which can be very wide, underlines Geoffroy Marx.
For him, the most problematic projects are often the oldest, some of which are installed in Natura 2000 zones. EDF was thus condemned by the courts for the destruction of kestrels, a protected species, in the park of Aumelas (Hérault ) which dates from the 2000s.
Researchers are working to better understand the causes of bird mortality in onshore wind farms and to measure the effectiveness of bird detection and scaring methods as part of a program, MAPE.
Wind farms have "impacts on biodiversity that we must control", acknowledged Nicolas Wolff, president of France Energie Eolienne (FFE) which brings together the sector in France Pascal GUYOT AFP / Archives
"Until now, it was evaluated with a wet finger," Olivier Duriez, lecturer at the University of Montpellier, told AFP.
It is now a question of "evaluating the excess mortality caused by wind turbines over 30 years" on different species of birds, knowing that for some, "a single death per year can endanger the species".
The hiccups
To avoid collisions, wind farms can be equipped with cameras and / or radars.
In some cases, humans can act as sentries.
This involves triggering sound or visual scaring devices or stopping the blades.
But there are some hiccups: "The evaluations of the cameras are made under optimal" meteorological conditions, while rain or clouds can have an impact on their operation, indicates Sophie Dupont, post-doctoral fellow.
Wind turbines under construction at sea off Saint-Nazaire (Loire-Atlantique), September 21, 2021 Sebastien SALOM-GOMIS AFP / Archives
The scaring "is relatively ineffective in the long term" because the birds get used to it, she continues.
And "the turbine's stopping time is very long": often the bird is not detected from far enough away to avoid a collision, adds Olivier Duriez.
Wind turbines at sea are of growing concern.
The LPO wonders about the cumulative impact of wind turbines at sea on migratory birds if projects multiply along their route.
Norman and Breton fishermen have made known their dissatisfaction.
In the Mediterranean, opponents are asking for a postponement of the allocation from next year of the first two floating wind farms.
The National Council for the Protection of Nature (CNPN) goes in the same direction, judging that "our knowledge of the potential impacts remains very partial".
He recommends "to apply a moratorium in the implementation of projects (new calls for tenders) in order to leave time at least for studies in progress".
© 2021 AFP