First Aircraft Detection Lighting System (ADLS) Approved for Operation in Fryslân, Netherlands

The ADLS system is deployed as a partnership between Windpark Fryslân and Terma and is the first ADLS solution in operation in the Netherlands. The installation and commissioning of the ADLS solution were finalized in 2021, followed by months of testing with verification flights and adjustments. 

Beginning of 2024, the Dutch authorities gave the green light to put the solution into operation. As of February 15 2024, the aviation lights of Windpark Fryslân installed at Kornwerderzand, have been turned off during nighttime due to Terma’s ADLS radar system becoming operational. The wind turbines aviation lights will only be turned on when an aircraft approaches Windpark Fryslân maintaining aviation safety.

By law, wind turbines taller than 150 meters are required to have intense aviation lighting. However, the lighting may cause annoyance to the communities and wildlife in the vicinity of the wind farm – this is minimized by the ADLS solution, as the system makes it possible to turn off the lights, only being activated if an aircraft enters the vicinity of the wind farm.

“It is an important milestone for Terma that our ADLS solution has now officially been put into service. Terma has been involved in the project from the very beginning to develop and implement the first ADLS solution in the Netherlands. Terma’s ADLS solution has been proven to reduce the ‘light on’ time of the wind farm by up to 95% - so it is a true benefit to the local community and surroundings,” says Henrik Bendix Nielsen, Security Sales Manager at Terma.

The Technology Behind ADLS

The Aircraft Detection Lightning System (ADLS) consists of an advanced radar system, an antenna, and a light control server. The intelligent lighting solution monitors the airspace above and around the wind farm.

When the airspace around the wind turbines is clear, the lights stay turned off. However, when an aircraft enters the wind farm area, the system automatically detects it and activates the required high-intensity lights. The lights are deactivated after the aircraft has left the wind farm area warning zone.

Moreover, earlier in the project phase a test took place to test the radar’s detection of aircraft using mobile radar demo equipment. The results were positively evaluated by the Inspectie Leefomgeving en Transport (ILT), which is the Dutch authority responsible for overseeing environmental and transportation matters. This trial confirmed the effectiveness and reliability of the ADLS system.

In compliance with the national regulatory, the radar surveils the airspace within a detection zone (approximately 10 km from the wind park), activating the wind park’s aviation lighting when the aircraft enters a warning zone (approximately 7 km from the wind park). The lighting is being deactivated with a time delay of 1 minute after aircraft leave the warning zone.

“Radar-based ADLS does not rely on any equipment being installed onboard an aircraft, it is a more advanced solution with higher precision and air safety than any other available technology. It is an advancement for the security of wind farms and surrounding airspace, but also an important mitigating factor for people and wildlife living nearby. We anticipate more countries and wind farms to follow suit in implementing ADLS,” says Henrik Bendix Nielsen.

Learn more about ADLS.

About Windpark Fryslân

Windpark Fryslân consists of 89 4.3 megawatt (MW) turbines, each with a tip-height of 180 meters. Annually, the wind farm will produce some 1.5-terawatt hours* (1,500,000 megawatt hours). This is approximately 1.2% of the electricity use in the Netherlands, corresponding to the consumption of some 500,000 households. Visit Windpark Fryslân