The past meets the future: 700-year-old castle illuminated by SGM

LED solution for an annual saving of 91% on power consumption


Koldinghus is a Danish castle built in the 13th century, located in the Danish city of Kolding. For decades, the castle has been illuminated by conventional discharge lamps, which is a costly affair in regard to both power and maintenance. Therefore, Business Kolding and the Municipality of Kolding decided to implement a new and more up-to-date lighting solution using SGM luminaires.

To make the texture of the old facade stand out in the best way possible, we used fixtures from SGM.

Frederik W. Borello.

P-2 illuminates 700-year-old castle

Apart from being expensive and high-maintenance, the old lighting solution did not contribute positively to the appearance of the old castle's architecture. The discharge lights with their fixed, non-adjustable color temperature gave the partly restored castle an inharmonious air, while the surroundings looked like an artificial environment. With no lens-replacement options, the lighting was uneven and formed large areas of both shading and over-exposure. Furthermore, with Koldinghus Castle being a historical and listed building, a potential new lighting solution had to adhere to several strict guidelines.

The overall aim for the new lighting project was to enhance the castle's historic and architectonic value through a proper illumination. Thus far, nobody had been able to present a lighting solution that would match all the requirements. Therefore, in 2015 Business Kolding hired ÅF Lighting to present their views on how to approach the task of properly illuminating the old castle. When it was time to decide on fixtures, various lighting manufacturers were invited to a shootout, and as a result SGM Nordic was brought on as official lighting partner to work with ÅF Lighting.

Uncovering the best solution
The strict guidelines stated that the location of the existing poles could not be altered, and neither could the amount of fixtures outlined for the project. Also, because of the protected grounds, it would not be possible to dig down cabling. At the same time, the design of the fixtures had to be stylish, but discreet in order for them to blend into the surroundings without drawing too much attention from the real subject of admiration, i.e. the castle.

SGM Nordic and ÅF Lighting, took up the challenge, determined to achieve the best lighting solution for the castle. An elaborate process of testing began. With assistance from Business Kolding, the project team started to elaborate investigations of the buildings and the surrounding areas. Further, the team set up testing of wireless communication to ensure the reach between all poles on the castle grounds from one central location. Testing complete, the team started drawing up a plan to install 38 x P-2 fixtures on existing poles surrounding the castle. These fixtures were chosen for the RGBW LED technology, their sleek, elegant design and the fact that they are IP65-rated, to guarantee that the fixtures will sustain – even in the harsh Danish weather conditions. Finally, with the P-2's different beam angle options – 15°, 21° and 43° – the team would be able to achieve the desired effect of an even light distribution on the castle facade.

The team was ready to present their proposal to the Danish Agency for Culture and Palaces, and with all the boxes ticked, the proposal was accepted and the SGM Nordic/ÅF Lighting team set out to start the implementation.

Unanticipated benefits and smiles all around
Today, the true beauty of the castle stands out with a discrete, but powerful LED lighting solution. Reflecting on the process, Frederik W. Borello, Electrical and Lighting Engineer with ÅF Lighting, said:

"Despite the obvious limitations and strict guidelines, we managed to overcome the hurdles and come up with an aesthetic lighting scheme that accounted for all the wants and needs of our clients. To make the texture of the old facade stand out in the best way possible, we used fixtures from SGM with RGBW LED's and accurately toned the light to make the nuances of the red brick facade appear natural and well-lit. By dimming the powerful fixtures, we avoided glare and kept the amount of light on the surroundings to a minimum."

The entire solution is configured wirelessly and controlled by the SGM A-4 Art-Net to DMX recorder/player. The P-2 setup provides the opportunity to dress the castle in various textures, effects and color schemes for special occasions such as national holidays and the local, annually recurring Kolding Light Festival.

Furthermore, maintenance costs have been lowered significantly as the fixtures' IP65-rating with SGM's dehumidification processor prevents humidity inside the fixtures, and the continuous bulb replacements, that took place regularly with the old discharge lights, will no longer be necessary with the P-2's LED technology.

As an added bonus, the Municipality achieved an annual saving of 91% on power consumption, which is the equivalent of 5 tons of CO2.

Products used

The installation comprises 38 x P-2 flood light fixtures with different beam angles mounted on existing poles surrounding the castle.


For this installation, the designer deployed products from our entertainment range similar to the products displayed below, which are POI versions with a higher IP-rating for permanent outdoor installations.


Lighting Design

ÅF Lighting

Electrical and Lighting Engineer

Frederik W. Borello, ÅF Lighting

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