Institutionals When the lights go out at the wind farm

The system for needs-based night-time signalling - BNK for short - ensures that the legally required red lights on wind turbines are switched off by default and only flash when an aircraft or helicopter is in the vicinity. Long announced, the legal requirement is to be mandatory from 2025. Following intensive technical and legal preparations, the first wind farm in the German Commerz Real portfolio put the new system into operation in February 2024. The wind farm with five turbines in Parchim (Mecklenburg-Western Pomerania) is part of a special fund for institutional investors.

All of the other 27 German onshore wind farms in the various Commerz Real funds will follow suit over the course of the year - this is the intention of the legislator, who enshrined the requirement in the Renewable Energy Sources Act in 2018. The requirement is intended to ensure undisturbed night-time peace and quiet and thus contribute to social acceptance of wind power. "The topic was completely new at the time and presented plant operators, authorities and manufacturers with the enormous challenge of retrofitting not only new plants, but also the almost 30,000 existing plants within a specified deadline," reports Bernd Müller, Head of Infrastructure Asset Management at Commerz Real. "The statutory deadline has been postponed several times, partly because there was initially no market for BNK systems. It is now expected to expire at the end of 2024. If this legal requirement is not implemented, operators face severe fines."

Specialists from Commerz Real's Green Deal Infrastructure division worked intensively on the implementation in cooperation with the respective technical operators UKB, BayWa, Juwi, Energiekontor and E-Service. The BNK systems used in the German Commerz Real portfolio utilise transponder technology, for which each individual wind turbine had to be retrofitted. The system scans the airspace for signals that all civil aircraft emit at short intervals. If an aircraft is within a defined radius of the wind turbines at night, the red lights are switched on to provide pilots with orientation.
The entire German Commerz-Real portfolio is now equipped with BNK systems. They now have to prove their functionality in practical tests - the so-called site-specific test - and be approved by the responsible aviation authority.