Proximity detection (ADLS) for new wind turbines

ADLS: an end to pointless blinking

An Aircraft Detection Lighting System, Proximity Detection in Dutch, ensures that the lights wind turbines only flash when a flying object is actually present in the the neighborhood. The systems detect the position and route of aircraft. While previous ADL systems were based on radar technology, detection based on transponders now commonplace. In this case, flying objects signals that are recognized by the systems.

ADLS based on Transponders offers two variants:

Multilateration: Different receivers determine the position of an aircraft based on the time differences when the signal is received. This method is particularly accurate, but requires a complex infrastructure.

One-touch approach Receiver: A single receiver estimates position based on signal strength and direction. This variant is simpler and cheaper, but less accurate.

Modern ADLS such as the Light:Guard system can use both approaches, depending on the location. In densely populated areas, multilateration allows for more accurate detection and longer phases without blinking. In isolated locations, a single receiver is often sufficient.

History of ADLS in Germany

The legal obligation for ADLS equipment was already laid down in 2019 in the Occupational Health and Safety renewable energy sources (EEG). It was originally intended that this would apply from mid-2020, but was repeatedly postponed - the last time until 1 January 2025 - due to technical challenges, certification issues and pandemic-related bottlenecks. However, suppliers and operators are now well positioned and many wind farms have already been able to activate their ADLS.

ADLS for new wind turbines

Some new power plants and new wind farms also already have an active or at least installed ADLS. This must be the case from the new year at the latest. New installations must be equipped with an active active system from the moment of entry into service without exception ADLS. Failure to comply with this requirement risks heavy fines: per kilowatt of installed capacity is charged 10 euros per month - for a 3.5 megawatt system, this amounts to 35,000 euros. Operators and project planners should therefore take into account the with ADLS.

Thanks to optimized processes, ADLS systems can now be installed more efficiently. Providers such as Light:Guard already cover large parts of Germany, which means that the systems are often ready for use within a few weeks.

Looking to the future

It is still unclear whether ADLS can be considered a success at all, as it is still too early to acceptance by the population. However, the first data show that show promising results: In areas with low air traffic, the wind turbines almost completely dark.

The technology also attracts international interest. In Austria, ADLS is used voluntarily and in the Netherlands it is already established. In the coming years, demand-driven night labelling is likely to become widespread worldwide – an advantage for residents and the night sky.