Putting an end to darkness: Modern LED lighting in Shelter systems

The dark season is approaching with great strides – and with it the poor visibility conditions. Bright light and good illumination are a must, especially in waiting areas, along busy roads or directly at the tracks to the streetcar. Accidents caused by a lack of light are commonplace. This should not and should not be the case. With modern and efficient lighting with LEDs, we want to ensure more safety in road traffic.This is a current topic especially in the municipality of Reichshof. There are about 200 bus stops here, many of them in the open countryside. No street light, no electricity – this means poor visibility and danger, especially in the dark season. Students from the Gummersbach campus of the Technical University of Cologne have addressed this problem and recently presented their project work “Autarkic solar lighting unit” in Reichshof-Mittelagger. The pilot installation puts the bus shelter there in the right light.

The Laboratory for Analog and Optoelectronics at the Technical University of Köln, Gummersbach Campus, has been cooperating successfully for many years with the company WSM in Waldbröl, which manufactures bus shelters, living containers and many other products. This cooperation can now be extended to the field of bus shelter lighting or, more generally, Shelter systems.
The entire stand-alone solar street light was designed, installed and metrologically verified by TH. Unlit bus stops pose an increased risk of danger, as mentioned earlier. In the past, a serious traffic accident involving a schoolchild occurred in the municipality of Reichshof. This event gave rise to the idea of (self-sufficient) bus stop lighting that is independent of the public power grid. The preliminary work for this project began back in 2014 with a lighting survey of bus stops in Reichshof. Then in 2015 everything was installed and completed. The bus stop we illuminate is located in Reichshof-Mittelagger, Eckenhagener Straße 4, in 51580 Reichshof.

Task and concept

Within the scope of the elective subject “Optoelectronics” the project was worked on by students under the guidance of Professor Dr. Bärwolff. Initially, the main task was to find out the suitable components for the project of a self-sufficient, solar street lighting through research, simulations and calculations. The selected components were then ordered. The corresponding block diagram is shown in Figure 1.

The work was carried out in cooperation with the company “Aggerenergie”, which agreed to bear the costs of the plant as a pilot project. The assembly of the materials, was carried out in cooperation with the company “Alternative Energiesysteme Oberberg GmbH” (AEO) from Bergneustadt.


For the construction of the system in 2015, first two solar modules with about 300 W power were brought to the roof of the barn and fixed there with an additional bracket for solar modules. In the control cabinet of the barn, the charge controller, the timer, a control cabinet socket and the calcium-silver battery (120 Ah) were installed by the students. Additional fuses were also installed. Furthermore, a dimmer switch was installed on the outside of the barn. The bus stop itself and the surrounding area are well lit with 2 LED luminaires of 900 lumens each. The schedules are programmed with the timer, so that 5 min. switches on the light before the bus arrives and later switches it off again automatically. An additional presence sensor is to be installed here. In mid-November 2015, a first test run of the system was carried out under the supervision of Professor Dr. Bärwolff. Shortly after the first test runs, the system was officially inaugurated by the village association and the mayor of the municipality Mr. Gennies and has been running self-sufficiently since the end of November 2015. The following photo shows the stop with the managing director of WSM Mr. Schenk, other colleagues and Prof. Dr. Bärwolff.

Finally, with the help of a data logger provided by the TH Köln – Campus Gummersbach, data from the plant was logged in order to be able to make a statement as to whether the plant is fully functional.
The data obtained show that the system is adequately sized for the dark season and has always functioned. This innovative and future-oriented project has illustrated that, with limited effort, it is possible to supply bus stops without a nearby power grid via energy from solar modules and illuminate them with LEDs. LEDs were the logical option for lighting, as they have lower consumption as well as a longer life and are much more powerful than conventional light sources. Furthermore, it was very interesting, because with the installation something was actually moved in the municipality of Reichshof, district Mittelagger, the residents were very interested and the pupils now find an illuminated bus stop in the morning and thus more safety on their way to school.


The system can be expanded or scaled down as required. It can also be pole supported. For this purpose, of course, it must be adapted to the ambient conditions prevailing at the installation site. For example, if the average solar radiation is very low at the location, the solar modules must be designed for high efficiency and possibly the number of modules itself must be increased. If an LED with 10 watts is sufficient, then depending on the position of the sun, the number of modules can also be reduced and still bring in a sufficient solar yield. There are also stops where the shading by trees or bushes is so great that a solar solution does not make sense. The whole system must be carefully calculated and designed depending on the location.

In considerations and suggestions by the village association, among other things, the idea came up to install a motion sensor, which in interaction with the twilight sensor and the programmed schedules, takes over the control of the LEDs. The positioning of such a motion sensor should be below the mounting device of the LEDs or inside the bus stop, on the one hand to minimize the triggering by passing motor vehicles and on the other hand to maximize the probability of triggering by movements of waiting persons under or at the bus stop.

In the meantime, other municipalities have also expressed interest in solar lighting concepts for bus stops and bus shelters. Here, interesting cooperations can develop, as already mentioned, between the Technical University Campus Gummersbach and the Fa. WSM initiate. The involvement of a professional company specializing in LED and lighting is planned. Talks have already been held with the company “We are brighter” (WSH) from Bergneustadt, the TH and the Fa. WSM took place.