The Huguenot Toll Tunnel provides a route through the Du Toitskloof Mountains which separates Paarl and Worcester. The 3,9km long tunnel was opened in March 1988, and is 11km shorter than the route across the pass. According to the Average Annual Daily Traffic (AADT), more than 12,000 vehicles travel through the tunnel daily.
It was decided to replace and upgrade the tunnel’s old fluorescent lighting and control system for the first time since construction. The requirement was for a complete design, supply and installation solution, including a lighting management system.
More than 6,000 LED striplights and more than 200 LED adaptation luminaires were supplied and are managed by the Advanced Tunnel Solution (ATS) control system.
With the upgrade of adaptation luminaires, the adaptation light levels have improved drastically. This eliminates the black-hole effect when approaching the tunnel during bright daylight, much to the benefit of motorists, who are now able to see clearly when entering the tunnel.
Furthermore, overall uniformities across the road surface of more than 85%, and longitudinal uniformities of more than 95%, were achieved.
BEKA Schréder has developed a customised LED striplight, perfectly suited for this tunnel lighting application. This South African designed and manufactured luminaire incorporates the latest LED technology and consists of an aluminium extrusion body and die-cast aluminium endcaps creating the best thermal environment for LEDs. Various light distributions are offered to provide the right amount of light, exactly where it is needed. The request for a continuous line of light throughout the tunnel was achieved with this unique luminaire design.
Each tunnel zone requires a different luminance level. The ambient lighting conditions and tunnel entrance as seen by an approaching motorist in the Access Zone is measured by a specialized luminance meter (typically referred to as an L20 camera). The L20 camera provides input to the control system which adjusts the light levels for each zone to follow the CIE curve (as per CIE88). The luminance level at the Threshold Zone is highest at the entrance of the tunnel and then decreases as you move into Transition Zones 1 and 2. Whilst driving through these zones, it gives the eye time to adapt to the lower light levels on the Interior Zone. As this is a bidirectional tunnel, both sides are treated as entrances with L20 measurements controlling the adaptation lighting.
Schréder’s advanced luminance calculation software analyses all aspects of a tunnel environment to provide the right luminance level in all tunnel zones. During the study, the number of luminaires to be installed in the tunnel and their orientation are calculated to create a curve as close as possible to the CIE normative curve for an efficient and economical light installation.
BEKA Schréder is delighted to have provided the lighting and control solution for this tunnel. The high-efficiency and long lifespan of the luminaires will enable the South African National Roads Agency Limited (SANRAL) to reduce its operating costs while delivering a much better service for commuters. This new lighting installation has not only improved the driving experience for motorists but will also ensure less closures and hold-ups due to maintenance for a more pleasant commute.
BEKA Schréder, leading local manufacturer of LED luminaires, is part of the Schréder Group. BEKA Schréder locally develops and manufactures sustainable LED lighting products, designed and suitable for local conditions.
BEKA Schréder, in partnership with Phoenix Contact, are very proud to be associated with SANRAL, Innovative Transport Solutions and LEAD Engineering Projects in providing a complete lighting solution for this prestigious project.
