The new BfN publication, “Species Protection and New Legal Provisions on Onshore Wind Energy Expansion”, provides a comprehensive, practice-oriented overview of the various legislative changes that have taken place since the amendment to the Federal Nature Conservation Act on 20 July 2022. In addition to examining the procedural simplifications set out in Section 6 of the Wind Energy Land Use Act (WindBG) and the amendment to the Renewable Energy Directive (EU 2018/2001 (RED)), the report focuses in particular on the prohibition on the killing of breeding bird species at risk of collision during the operation of wind turbines, as set out in Section 45b of the Federal Nature Conservation Act (BNatSchG). Dealing with the newly introduced reasonableness threshold poses a particular challenge for nature conservation and planning authorities when it comes to weighing up the protective measures still available for affected bird and bat species.
The only effective measure for protecting bats is to impose operational restrictions based on wind speed and temperature. Using a simulation model that has been developed, it is demonstrated, amongst other things, that in most federal states the blanket operational requirements defined for the protection of bats are at odds with the maximum number of bat fatalities per wind turbine per year. The parameters for flat-rate operational requirements that have been established to date and are applied in practice – often 6 m/s as the cut-in wind speed and temperatures above 10 °C – have not been adapted to the scale of modern wind turbines. As the rotor diameter of new wind turbines continues to increase, stricter blanket operational requirements would now be necessary for the new turbines – all other conditions being equal – in order to reduce the risk of collision to the prescribed level whilst bat activity remains the same. The recommendation is therefore for more efficient, differentiated precautionary operational requirements, which were developed as a standardised nationwide method in a further R&D project by the BfN and presented in a publication (BfN Schriften 682) in 2024.
Wulfert, K., Vaut, L., Lau, M., Köstermeyer, H., Blew, J. & Engel, E. (2025): Artenschutz und rechtliche Neuregelungen zum Windenergieausbau an Land. Unter Mitarbeit von: Behr, O., Greule, S., Grimm, J., Scholz, T., Simon, M., Stehr, F. BfN-Schriften 760, Bonn, 2025.