The Barcelona City Council, within the framework of its infrastructural plan to change and improve the region’s public lighting, switches to LED technology in tunnels, confident that this is the technology driving the current market. The Bonanova tunnel is the first challenge that involves Barcelona city, after the good experience and the results achieved in the Miramar tunnel on the Montjuïc mountain.
The project aimed the adaptation of new technology and as a consequence, energy saving. The tunnel is located on one of the city’s most important roads, since it allows access and exit to and from the city through the Sierra de Collserola and the Vallvidera tunnels, but also provides access to the Barcelona Highways surrounding the city. The tunnel has two traffic directions, with two lanes in each direction and with a road width of 14 m that support high volume of traffic.
The tunnel is 173 m long, on a slope and in a curve in the descending entrance, that is, in the direction to the city. The orientation of the tunnel entrances and the field of vision in one provides different L20 and Lth, so the new solution had to be designed to personalize and obtain a different level in each entrance.
The old lighting solution contained HPS HID fixtures using 400, 250 and 150 watts installed in both axles of the tunnel at a height of 3.75 m.
Tungsram, with its TLBT and TMBT fixtures series, offered an optimized solution with excellent uniformity and illumination not only from the horizontal plane but also from the vertical one that substantially upgrades the old solution. The fixtures used incorporate an optical system based on reflection and not on channeling through lenses. The light source (led) projects onto anodized and polished aluminum reflectors, obtaining excellent performance and the appropriate photometry at the same time. This system undoubtedly helps to minimize possible glare and feelings of discomfort users may have, since the light source (the LEDs) is set back (hidden) with respect to the plane that defines the glass that protects the fixture, thus avoiding direct vision and a wide range of led viewing angles.
The solution that made it possible to provide the tunnel with day and night lighting, according to current regulations, with 224 cd / m2 in the descending entrance, 180 cd / m2 in the ascending entrance and with 4 cd / m2 inside, was designed based on the installation of
The new energy consumption of the executed solution is approximately 53.8kw. This optimizes the power to be consumed by approximately 46%, considering an alternative based on the old HID technology based on 400, 250 and 150 w fixtures. In addition, the devices used are equipped with drivers with the ability to interpret a regulation order through a DALI signal, necessary for the new control system that is being designed, a system with adaptive capacity to traffic conditions and exterior light.
To sum it up, the solution provides a better visual quality to the installation, lighting levels adapted to new regulations and energy benefits that not only justify the investment due to its rapid return, but also the new installation will require less investment in maintenance.
