The City of Joensuu has 22,000 outdoor light fixtures, and their intelligent management saves electricity and the citizens’ nerves as well as reduces light pollution.
The City of Joensuu is responsible for the outdoor lighting of streets, parks and sports facilities and has been replacing their lights with LEDs on its own initiative for already a decade. The majority have been replaced by now, and the rest will be replaced as the need arises.
Previously, lighting at night was rationed in the city centre and used to be completely turned off in small locales. Even in the city centre, half of the lights were turned off.
Thanks to LED lights, lighting can be adjusted according to the time of day instead of being switched off.
Thanks to LED lights, lighting can be adjusted according to the time of day instead of being switched off. With the exception of the brightest summer months, the lights are always on, because it has little economic impact.
‘On the other hand, lighting has a major impact on feelings of safety and the smoothness of everyday life,’ says City Engineer Tero Toivanen.
‘The LED lights have a five-step dimming system, which means that the lighting is automatically dimmer at night than it would be during busier times,’ Toivanen clarifies.
Electricity consumption has been approximately 70 per cent lower than with constant bright lighting.
LEDs have saved a pretty penny
Street lights that brighten and dim automatically can save a lot of money. Joensuu has also tested this in Penttilänranta, where footpath lighting is equipped with motion sensors.
The sensors react to approaching pedestrians or cyclists, which makes the light grow brighter. After the light post has been passed, the light dims again. Electricity consumption has been approximately 70 per cent lower than with constant bright lighting.
Altogether, these measures have reduced the amount of energy used for lighting in the city to as low as 40 per cent of previous levels.
Faults reported in near real-time
The city has nearly 22,000 outdoor light fixtures. Until a year ago, they were managed by a single control system. However, the system became obsolete and was replaced. Now Joensuu has approximately three hundred street light hubs managing about 70 street lights each.
‘Faults are reported to the system almost immediately,’ Toivanen says.
‘The lighting also seems to be of great interest to the citizens. We receive feedback very quickly if a citizen feels that the lights are on for too long or if a light fixture elsewhere has gone dark. Lighting is a concrete issue that affects all of our everyday lives’, Toivanen says.
This material was produced as part of the activities of the City of Joensuu Innovation Ecosystem Agreement (ERDF), co-funded by the European Union and the city of Joensuu.
