In 2018, the Slovenian municipality of Pivka converted its entire municipal lighting to LED technology as part of a major project. The combination of technical and decorative lighting as well as facade illumination saves 80 percent of electricity costs and complies with all government requirements regarding light immission.
Measured in terms of light, time in Pivka had stood still about 40 years ago. Globe luminaires, light pollution, mercury vapor lamps and inadequate lighting levels. It was all part of the cityscape. Pivka, though, is not a bit old-fashioned. The active municipality in the southwest of Slovenia, only 50 kilometers away from Trieste in Italy, is one of the most developed municipalities in the country despite its population of only 6,000. With the support of European subsidies, attractive museum and tourist complexes have been created in old military barracks and a new park and eco-museum were established. In 2019 Pivka was awarded the "Zlati Kamen" prize (translation: the 'Golden Stone'), a type of Oscar for communities, as the best developed municipality in Western Slovenia. Refurbishing the entire public lighting system was the next logical step in this context. And Mayor Robert Smrdelj intended to kill several birds with one stone: Reduce electricity costs, improve the quality of light and create an attractive atmosphere in the city center—whilst complying with government requirements. Because in Slovenia, zero percent light pollution is prescribed by law.
In Pivka's case, SITECO drew up a holistic approach that combined technical and decorative street lighting with projectors for displaying and showcasing churches, monuments, facades, billboards and signage. Highly efficient, high lumen-output Streetlight 20 luminaires were installed in all streets of the municipality whilst decorative DL® 50 luminaires create an appealing atmosphere around historic buildings in the town center. In combination with already existing decorative masts and multiple brackets, an aesthetic solution has been created that enhances the townscape by day and night.
At the same time, DL® 30 luminaires installed around monuments replace obsolete spherical luminaires that, according to their design, emitted light into the upper hemisphere—a solution that no longer complies with legislation in Slovenia. Floodlight 20 projectors were installed to illuminate churches, facades, panels and signs. The optical system of these luminaires directs the light with especially high levels of precision. "We specified extremely narrow beam variants here. In this way we also achieve the legislatively prescribed zero percent light immission despite upward inclination," stated SITECO Project Manager Klavdija Tonejc.
When it comes to environmental protection, the community even goes one step further: Pivka is the first community in Slovenia to utilize warm white lighting with 3000 Kelvin. This light has a much lower blue component in its color spectrum—positive for people and positive for the environment and nature. For example, nocturnally active insects are much less affected in their natural behavior by this warm white light. A different light color (4000 K) is only used at crosswalks to increase attention at these hazard points. In total, more than 1,200 light points were replaced during the refurbishment. According to the local authorities, this saves them around 80 percent of their previous electricity costs. This has been made possible thanks to highly efficient LED technology in conjunction with control options such as programmed nighttime reduction. "Between half past nine in the evening and four in the morning, Pivka dims the luminaires firstly to 50 percent luminous flux and then later to 30 percent," informed Tonejc. Luminaires operate at 100 percent throughout the night only at crosswalk locations.
The project's financing concept is also particularly interesting for the municipality: The investment does not swallow up any of the municipality's own budget. Rather, it meets all costs thanks to savings in electricity overheads and energy. "We were able to convince the municipality in all stages of the tender—with the concept, price, energy savings, luminaire data, guarantees as well as several other factors. It was a highly constructive dialog at eye level from start to finish," said Project Manager Tonejc. Mayor Smrdelj expressed his satisfaction accordingly. The project is a prime example of how to avoid light pollution and negative environmental impacts while simultaneously reducing electricity overheads and public lighting expenditure.