FE 77.0603/2022 - Optimisation of street lighting for 30 km/h zones and high-speed cycle traffic
The aim is to make transport in cities more efficient, safer and more environmentally friendly. A key issue is the introduction of extensive 30 km/h zones. Cities such as Aachen, Augsburg, Freiburg im Breisgau, Hanover, Leipzig, Münster and Ulm are testing 30 km/h speed limits on a large scale in pilot projects. Only on the few main roads is the usual speed of 50 km/h still permitted. On the other hand, the lower speed limit of 30 km/h is not only intended to increase safety for pedestrians and cyclists, but also for car traffic itself.
The luminance technology currently used in accordance with the DIN EN 13201 standard for the design of fixed street lighting is based on driving speeds higher than 30 km/h and can therefore lead to incorrect dimensioning of the lighting when used in 30 km/h zones, possibly with non-environmentally friendly overlighting of the road. For those roads that primarily serve the 30 km/h zones, other observation geometries can be assumed that are not taken into account in today's luminance technology with higher design speeds. In addition, the parameters observer location, viewing direction of the observer and the calculation field should be adequately redefined. Further questions about the dimensioning of the quality indicators belonging to luminance technology (mean road luminance or overall uniformity) or even the consideration of other key figures must also be investigated in order to significantly improve the visibility of obstacles and the visibility of lateral bicycle and pedestrian traffic (peripheral field of visibility of car traffic).
The aim of the research project is to develop a photometric evaluation method that enables a target-oriented and correct determination of the lighting level on traffic roads in 30 km/h zones and also on cycle paths and cycle lanes for high-speed cycle traffic. The process is to be based on luminance technology. In addition, it must be investigated whether, in return, it would be possible to change the low beam headlights on the motor vehicle in 30 km/h zones at the same time.
The evaluation procedure to be developed, such as the modification of the low beam for motor vehicles to be developed, would help to avoid the non-environmentally friendly overlighting of 30 km/h roads and cycle superhighways in the future and thus save energy without an inadmissible loss of visibility of obstacles and road safety.