The most accurate ADLS. From the German experts – for your wind turbines.
Turbines under contract
Receivers installed
Light Control Units installed
Lights off for wind turbines
Wind turbines are equipped with obstruction lights to be visible in the dark for air traffic. Those obstruction lights blink from dusk till dawn, no matter if an aircraft is nearby or not. This constant blinking has proven to be an obstacle in the acceptance of wind power.
To stop the unnecessary blinking and to make the night sky dark again, there is a technology called Aircraft Detection Lighting System, ADLS for short.
Through ADLS, it is possible to turn off the blinking obstruction lights of wind farms. This is done by monitoring the airspace around a windfarm. The obstruction lights of the wind turbines are only activated when an aircraft is in the vicinity.
In Germany, the use of ADLS on wind turbines is required by law. Following a recent extension, the implementation deadline for operators is January 1, 2025. With this expertise, we are committed to bringing ADLS to other countries as well.
The light:guard system for Aircraft Detection Lighting System is type-tested and meets IEC and ICAO standards. We already equipped some wind farms abroad with our ADL system and would be more than happy to provide you with a customized solution.
On-demand lighting
Every flying object is obligated to send out transponder signals to be identifiable. Those are being received by the Light:Guard receivers.
The system receives continuous data from all receivers at once and is therefore able to achieve a higher network coverage than each individual receiver would by itself.
This leads to a better signal quality and higher light-off times for each wind turbine, especially in areas with high air traffic or large wind farms.
to all operators whose wind turbines are configured for ADLS connection
what we accomplished so far
Receivers installed: the Light:Guard Receiver (LGR) receives transponder signals from the flying objects
and can recognize whether one is in the vicinity. Not every wind farm needs its own receiver.
Receivers online: these receivers are currently transmitting data and form our receiver network.
Multilateration (see above) is therefore already possible throughout Germany.
Light Control Units installed: the Light Control Unit (LCU-T) is the interface that
controls ADLS in the wind farm. Usually every wind farm requires an LCU-T.
Light Control Units online: These LCU-Ts are connected to our system.
Everything is installed in these wind farms and ADLS is theoretically functional.
Wind farms measured: each individual ADLS requires such a survey or site-specific
proof of functionality. Transponder signals are sent to the receiver and thus simulate
a flying object. Only then can ADLS be approved and activated.
Wind farms fully certified: the certificate is confirmation for the authorities that our ADL system
is functioning properly, meets the requirements of the AVV and can be activated. Some ADLS manufacturers
already count this as "turned dark". However, this is not entirely correct. For the lights to go out,
the final approval from the authorities and signal transmission by the system manufacturer is still missing.
Wind farms turned dark: approval has been given by the authorities, the turbine manufacturer
forwards the signal. The ADL system is active and the lights in the wind farm are off. This is how it looks like: ADLS in action (Video).
last updated: 23rd December 2024
Send us an inquiry and we will be happy to provide you with an individual and non-binding offer.
Frequently asked questions about Aircraft Detection Lighting Systems
Wind turbines, officially known as wind turbines, flash to make them visible to air traffic in the dark. This is intended to prevent collisions with airplanes and helicopters. In Germany, this obstacle marking is regulated by the “General Administrative Regulation on the Marking of Aviation Obstacles” (AVV marking for short). According to the AVV, wind turbines must be marked from a height of 100 meters. To ensure that they no longer flash all night, the use of an Aircraft Detection Lighting System will be mandatory from 2025.
Wind turbines flash red at night in order to be visible. This night-time marking is carried out by means of so-called hazard lights, fire W red or blade tip lighting. The color and light intensity are prescribed. Daytime marking is also mandatory on wind turbines. However, this mainly includes the stripes on the turbine (see question after next). In some cases, wind turbines also flash white light during the day, but this is the exception.
The flashing pattern, color and intensity are prescribed by the aviation authority. It depends on the type of lighting installed. Fire W red, for example, flashes in the specified sequence 1s on/0.5s off/1s on/1.5s off.
The stripes on wind turbines are part of the daily marking. The day markings are usually made using colored markings. These can be attached to the mast and rotor blades.
An orange or red stripe six meters wide is required on the rotor blades from a total height of 100 meters.
The mast must be marked at a height of 40 ± 5 meters above the ground. An orange or red colored ring three meters wide (six meters for lattice masts) should be used. This is required if the total height exceeds 150 meters. It is also required if the total height exceeds 100 m and the machine house is not marked. In this case, the second orange or red stripe on the rotor blades is also dispensed with.
Aircraft Detection Lighting Systems (ADLS) offer several advantages:
Reduced light pollution: less night-time lighting means less disturbance for residents and nature.
Increased acceptance of wind power: Residents are more willing to accept wind turbines in their vicinity if night-time lighting is minimized.
Energy savings: Lighting is only used when it is really needed, which saves energy.
Precise predictions with percentage values are difficult to make across the board. In some wind farms, the light:guard system achieves light-off times of almost 100%. However, it depends very much on the location and the region. Next to an airport, the reduction in lighting is not nearly as significant. The flight activity is simply too high here. In general, of course, the safety of air traffic must be guaranteed. For this reason, it does not make sense to state or interpret percentages regardless of location.
An example of an ideal case is the wind farm Groen in the Netherlands. Here, the light:guard system was able to reduce flashing by over 97%, despite high flight activity. The exact results can be found in this case study.
There are two approaches to this: Multilateration and Single Receiver Approach.
Multilateration: With this method, the position of an aircraft is determined by receiving transponder signals at several receivers. The signals are received at different locations and the time differences are used to calculate the exact position of the aircraft. This method is very precise and can also accurately determine the altitude of the aircraft. However, it requires several receivers, which increases the costs and installation effort.
Single Receiver Approach: This method uses only one receiving station to receive the signals from transponders. The position of the aircraft is estimated based on the strength and direction of the received signal. This method is less accurate than multilateration and can have difficulties in determining the exact altitude. However, it is cheaper and easier to install as only one receiving station is required.
Multilateration (MLAT) is a well-known and proven method in aviation. The position of a flying object is calculated by measuring the different arrival times of the same radio signal at different receivers. The light:guard system for Aircraft Detection Lighting System works at most locations by means of multilateration and can therefore achieve particularly accurate results. Multilateration requires the following elements:
Transponder receiver (Light:Guard receiver): There are several transponder receivers at known locations with synchronized clocks. These receivers receive the transponder signals transmitted by airplanes.
Time measurement: When an aircraft transmits a transponder signal, this is received by the various transponder receivers. Each transponder receiver measures the time it takes for the signal to reach it.
Triangulation: Positions can be calculated using the time differences in the transponder signals between the various transponder receivers. This is done by triangulation. The position of the aircraft is determined by the intersection of the time measurements from different receivers.
Error correction: As the transponder signals require a certain amount of time to reach the receivers, a number of factors must be taken into account. These factors are the transit time of the signal, possible reflections and atmospheric conditions. Algorithms correct the errors and calculate the exact position of the aircraft.
A transponder is an electronic device that is installed in aircraft. It emits a signal that is received by radar systems on the ground. This allows the position and altitude of the aircraft to be precisely determined. In aviation, transponders are used to make the position and altitude of an aircraft visible to air traffic controllers on the ground.
Transponder-based ADLS: With these systems, the position of flying objects is determined by the transponder signals they emit. Only flying objects equipped with a transponder are recognized. These systems are very accurate and require less infrastructure on the ground.
Radar-based ADLS: These systems use radar signals to detect aircraft in the vicinity of wind turbines. They can detect all flying objects, regardless of whether they have a transponder or not. However, radar ADLS requires more technical infrastructure and can be more expensive to install and maintain.
Active and passive radar are two different types of radar systems.
Active radars actively emit signals that are reflected by an object and then received by the radar. The time it takes for the signal to return is measured to determine the distance and speed of the object.
In contrast, passive radars receive signals emitted by other sources, such as radio or television transmitters. Based on the interference or changes in these signals, a passive radar can detect objects without emitting signals itself.
Both types have their own advantages and disadvantages, such as the stealth characteristics of passive radar, which can make it more difficult to be detected by traditional active radar systems.
The Light:Guard receivers cover almost all of Germany with their reception radius. 50,000 km² of this area has already been surveyed and certified in accordance with AVV. New ADLS systems can be put into operation very quickly in this area.
Wind farms in one of the surveyed areas can receive ADLS in eight weeks. If the systems are ADLS-compliant, we guarantee installation and certification within eight weeks. By sending us a brief inquiry, we can quickly find out whether your wind farm is eligible.
In other countries this is different of course. To find out how fast we can bring ADLS to your wind farm please contact our representative for your country.
In 2017, the German government announced that on-demand night-time marking may be carried out with activation of the lighting. Since then, there has been no other statement from the. That is why we also activate the ADLS at dusk. We work on the basis of the Astro Clock, which tells us when it is astronomical night.
There can be many reasons for active firing despite the ADLS system being in place. The most common reasons include
Flight activity in the airspace:
In this case, Light:Guard can carry out an extended airspace analysis that identifies the transponder that led to the activation. Of course, we cannot switch it off.
Signal interference:
Bei solchen Störfällen wird die Unterdrückung der Befeuerung automatisch aufgehoben (Fail-Safe-Mechanismus). So ist ein kompletter Ausfall der Beleuchtung und daraus resultierende Gefährdungen ausgeschlossen.
Single turbines are flashing:
The better the signal quality of the ADLS system, the more light emissions can be reduced by flashing. Light:Guard is continuously working to improve airspace monitoring by
These analysis programs are of course also made available to customers.
