By 2020, the city of Sulzbach-Rosenberg plans to convert 90 percent of its public lighting to LED. With 550 new Streetlight 11 luminaires from SITECO, a major step has already been taken in this direction - with a positive effect on traffic safety, municipal coffers and nature. Funding from the Federal Environment Ministry makes such renovations doubly interesting.
Consequent renovation of street lighting since 2012
"Living in gentle hilly landscape" - so advertises the City Sulzbach-Rosenberg on its homepage. The "ducal city with flair" with its 20,000 inhabitants is located in the middle of the Upper Palatinate, some 80 kilometres north of Regensburg and 50 kilometres east of Nuremberg. Tranquil? Perhaps. Overslept? Absolutely not. At least when it comes to public lighting and its conversion to efficient LED solutions, Sulzbach-Rosenberg is well ahead of other cities. "We have been converting everything to LEDs for years," says Roland Segerer, master electrical engineer at the city administration. In 2012, the Federal Environment Ministry (BMU) applied for funding for lighting refurbishment for the first time. The Streetlight 10 from SITECO has already made its way into the city in the Upper Palatinate. It replaced the oldest luminaires in the main traffic areas, which were still equipped with mercury vapour lamps (HQL). Throughout 2018, the 20-year-old luminaires were replaced in parks, residential streets and collecting streets. The solution of choice: a total of 550 Streetlights 11 from SITECO. It is the successor to the Streetlight 10 with a similar but slightly modified design and even more efficient technology on board. Only power variants in the micro size for parking paths and mini for service and collecting roads with spot heights between 5 and 9 metres were used.
70 percent less energy consumption, 50 percent lower electricity costs
In order to receive BMU funding again for this renovation section, the city had to save at least 70 percent CO2 with the new street luminaires. "We could easily achieve this with the Streetlight 11," says Peter Schmidt, application expert for outdoor luminaires at SITECO. The former HQL luminaires with a system output of 89 and 137 watts respectively are compared with the Streetlight 11 in the Plus variants used with values between 14 and 60 watts, depending on size and lumen package. The situation is similar for the replaced linear luminaires, whose tubular fluorescent lamps also consumed significantly more (2x 44 W).
In addition to the efficient LED luminaires themselves, the municipality is generating further savings potential through the possibility of lowering the level. "We first dim to 80 percent of the luminous flux and then to 50 percent during the night," explains Segerer. As a result, Sulzbach-Rosenberg now spends only half as much on electricity as before the refurbishment - despite rising electricity prices and many additional light points due to new construction.
LED street lights without light pollution
The renovation benefits not only the municipal cash register, but also the environment. Part of the modernisation was also the luminaires on the existing whip poles in the urban area. "The masts have an inclination of a good 13°. This scatters light upwards," says Peter Schmidt. Light pollution of the night sky is the result. But: "Thanks to the adjustable pole attachment of the Streetlight 11, we were able to remove this inclination so that the light is only emitted into the lower half of the room," Schmidt continues. The light immission is therefore zero. At the same time, the LED light attracts significantly fewer post-active insects due to its lower blue content. But the whip poles posed a particular challenge not only in terms of environmental protection - but also for lighting technology. The problem: with this mast shape, the cantilevers protrude about two meters into the street. "This illuminates the road well. But light is also needed on the sidewalk," explains Schmidt. SITECO has developed a special light distribution system for these cases: Here, three of the four elements of the LED module illuminate the road, while one element brings the light back to the mast and onto the pavement - for homogeneous illumination without dark spots. This is made possible by the very precise reflector technology with which the SITECO luminaire directs the light in a targeted manner.
Comfortable commissioning of the new street lighting
Despite all technical features - Roland Segerer was ultimately convinced by the daily handling of the light. All installations, conversions and settings are carried out by the operator together with only one colleague. Uncomplicated solutions that are easy to install and program are therefore the be-all and end-all for him. "The best thing is that we can parameterize the Streetlight 11 simply and completely freely according to our ideas," says the master electrical engineer.
Finally Sulzbach-Rosenberg has even more planned. The next stage of renovation for 2019 has already been decided: then it will be the turn of the luminaires with sodium vapour lamps (NAV), still the most efficient of the "old" technologies, mainly used in younger housing estates and spotlights, with which some historic buildings and facades are illuminated. By 2020, at least 90 percent of urban outdoor lighting should be converted to LEDs.