Lighting of the first underwater roundabout. Faroe Islands
The autonomous Faroe Islands archipelago, part of the Kingdom of Denmark, comprises a total of 18 volcanic islands, 17 of which are inhabited by barely 50,000 people. The archipelago has rugged mountainous terrain, and the islanders need a road traffic system that keeps them connected.
This article addresses...
- THE FAROE ISLANDS
- A HUGE CHALLENGE
- THE FINAL SOLUTION
The Faroe Islands
The autonomous Faroe Islands archipelago, part of the Kingdom of Denmark, comprises a total of 18 volcanic islands, 17 of which are inhabited by barely 50,000 people.
The archipelago has rugged mountainous terrain, and the islanders need a road traffic system that keeps them connected. Current transport methods include ferries, overpasses, bridges and road tunnels.
The islands currently have some 20 tunnels, including those which are still under construction. The most famous is the Eysturoy underwater tunnel. It has three conduits stretching more than 11 km connecting the capital Tórshavn with the cities of Strendur and Saltne. It is one of the most substantial public infrastructure projects in history.
The tunnel complex has the first underwater roundabout in the world, linking the three branches that connect the aforementioned cities.
A huge challenge
In 2018, the technical department of Secom Iluminación, in collaboration with Tectal, accepted the challenge of creating a comprehensive solution for the entire Eysturoy tunnel complete with its underwater roundabout. This would entail a lighting study, manufacture of the light fixtures and their respective approval.
The underwater roundabout was the first of its kind in the world. This meant there was no existing point of reference for the project, and design guidelines and criteria had to be established. As manufacturers, we were in a position to adapt the lighting system to the specific needs of each section of the project.
We also conducted an exhaustive methodical study of each critical point, since we faced all the problems of roundabout and underwater tunnel lighting in one project.
The first thing to consider were the quality criteria. Given the scale of the project, the light fixtures had to be carefully selected to ensure they met a series of technical requirements.
- Regulations: An accredited entity verified the testing and reliability certifications for the items.
- Materials: Our light fixtures are treated to prevent corrosion over time. The electrical components are manufactured in Europe and come with a guarantee and superior reliability.
- Lighting: The selected fixtures have a high-quality Osram light source which more than meets the required lighting requirements.
- Geometry: In this unique project, the light fixtures had to comply with a series of restrictions to facilitate their installation and orientation in accordance with the tunnel geometry.
After the quality of the proposed lights had been demonstrated, we moved on to the lighting study.
This project comprised two distinct sections:
- Straight sections: We conducted a lighting study over an extensive section and, since the typology and dimensions were the same throughout, extrapolated the results to the total 11-km of tunnel.
- Roundabout: The study in this highly unusual case implemented the light fixtures over a metallic structure located in the central part of the road, taking into account the reflection off the walls and the large solid central column.
In both cases, we selected a type of light that would maximise efficiency via the installation of as few fixtures as possible while complying with the established lighting requirements.
These floodlights come with an 80-degree aperture as standard. However, we wanted a 120-degree aperture to achieve a widespread lighting effect rather than focussing the light to a central point on the ground.
To solve this problem, we opted for a specific opal diffuser that would increase the aperture of the beam of light and create a more uniform lighting effect while reducing the potential for blinding drivers.
The light fixtures would need to hold a large number of electrical components and cabling, hidden from view. To get around this, we manufactured a special box-shaped canopy for attaching and orienting the floodlight and providing watertight housing for all the electronics.
As manufacturers, we can adapt any part of a light fixture and tackle any problem.
The lighting had to be RGBW, so we opted for a coloured LED light, control and regulation devices, and all the equipment necessary for effecting colour changes or the desired sequences. This was a relatively innovative solution – both the roundabout and the 11km of tunnel have a type of decorative lighting that allows for modification of colours and light intensity and the creation of sequences.
The solution supplied by the Secom Iluminación brand was well received and overcame all challenges.
As for the results, you can judge for yourself.
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