Again, the city police of Grenchen is testing a lighting system for pedestrians - this time on the Flurstrasse with innovative LED lamps.

az Grenchner Tagblatt from Oliver Menge     23.5.2015 um 14:00 Uhr

Urs Schütz and his men, employees of the construction department, cut eight circular holes of exactly 16.5 centimeters diameter into the asphalt, four on each side, on the pedestrian strip on the Flurstrasse north of the GVG roundabout between the Rötistrasse and the Diebold-Schillingstrasse.

In these holes, solar-powered LED lamps are to be sunk, which are intended to draw the attention of motorists to the pedestrian strips. "The worst is early in the morning," explains Michael Herzog, Head of the Traffic Police Department. "Many drivers are driving in their vehicles, mentally but still at home or at work, just somewhere else."

This increases the danger of overseeing someone who wants to cross the street. "We are now equipping this pedestrian strip with LED lights, which should attract the attention of the car drivers and make them more mindful." The pedestrian strip on the Flurstrasse was deliberately chosen, but it is only badly-lit. Only a single road lantern, which is not directly at the strip, but a little further away on the Diebold-Schillingstrasse, throws her light on it.

In the meantime Urs Schütz has stirred a special cement in a bucket, "actually it is a lot of cement-based chemistry," he says. As a result, the lamps are glued to the asphalt. The reason: in the case of temperature fluctuations, the different materials do not behave the same, which would lead to the asphalt being lowered more or less around the lamp. The special adhesive prevents this.

This is the second pedestrian strip in front of the Kastels nursery, where a lighting concept is tested - with a big difference: the pilot pedestrian strip at the Kastels was equipped with a fixed and correspondingly expensive lighting. The one on the Flurstrasse - according to Herzog, a highly frequented school route - is equipped with solar-powered lighting elements. "This system is more cost-effective and as efficient as the other."

Smart solar system

The SolarVision SV2 system consists of a solar cell, a built-in microprocessor and a battery pack that feeds two or three LEDs. The whole is enclosed in an aluminum steel housing of 3 centimeters height and 16 centimeters diameter, which is installed in the asphalt in the ground. During the day the battery charges, in the dark, the LEDs turn on, they are about one kilometer far to see. "The system is smart: when the road is snow-covered, for example, the microprocessor turns "OFF" the lights.

When sun light falls on the solar cell, the system turns itself "ON" and recharges the battery within a few seconds, explains Herzog. It does not make sense if the LEDs burn under the snow. The battery service lasted longer than one night, which is why a temporary coverage or bad weather is no problem. Other advantages: Properly installed, a snow plow can also clear the road without problems.

One of the LED systems costs CHF 450, per pedestrian strip arround 3600 francs. According to Michael Herzog, Head of the Traffic Police Department, a total of eight pedestrian strips are to be equipped with the new system, if it proves successful. "It is a question of providing more security, especially where many children have to cross the streets."