Brussel’s public lighting is currently programmed to switch on from dusk to dawn according to the solar calendar, taking into account various parameters such as the season and the location of the luminaires. Based on this information, the system schedules a reduction in the lighting levels at certain times of night.
Building the Smart City of the Future
For 3 months at the start of 2021, Sibelga who manages the public lighting for the city and Schréder tested an innovative smart street lighting system along Bois de la Cambre, a large urban park in the south of Brussels.
This area is an ideal location to test smart lighting as a major artery leading into the city runs along this park which is also very popular with residents meaning traffic can be very heavy, with cars, cyclists and pedestrians using the road. In addition, as this green area is rich in biodiversity, it also made perfect sense to minimise any light pollution.
From 1st February to 29th April, the light output of 72 CITEA NG LED luminaires lining the road and in the park was no longer adapted according to the predefined schedule but based on data collected in real time. This data was not captured by sensors installed on the luminaires but through online databases on the Internet.
Three types of data were collected:
- location of pedestrian crossings.
The data coming from the databases enabled the Schréder EXEDRA system to calculate the optimal lighting levels of each light point and if necessary adapt the light every 15 minutes to real-time conditions. The light output was adapted according to 3 different levels (100%, 75%, 50%) to maintain the required lighting standards for the city.
Specifically, the lighting level was automatically reduced when the traffic density was low and the weather conditions were good. If it was raining or if there were strong winds (which could blow branches onto the road), the lighting level did not decrease.
The luminaires on the pedestrian crossings were not involved in the pilot project to maintain the lighting levels at 100% at all times and ensure safety.
Our mission is to support large and small cities, by developing easy-to-use control systems that harness the full potential of technology to better serve citizens. We want our smart lighting solutions to generate even more energy savings while preserving nature and the night sky as well as ensuring safety and comfort in our cities.
More energy savings and less light pollution while ensuring safety
If we compare the energy savings that would have been achieved by dimming the light levels by 50% every night between 10p.m. and 5a.m. with the savings achieved during these 3 months of tests, we can see an additional reduction of 13% on Avenue de Diane and 17% on Avenue de la Belle Alliance.
On this basis and taking into account the various lighting schedules and climatic conditions throughout the year, we estimate that over a full calendar year, this type of system could generate an 10% increase in energy savings. Furthermore, lowering the light output has also made it possible to minimise any light pollution, with no impact on the safety or comfort of people using the road.
Thanks to this pilot project, Sibelga and Schréder have demonstrated that an adaptive public lighting system can:
- ensure an optimal level of comfort and safety for users (pedestrians and motorists);
- reduce light pollution and preserve the environment;
- lower electricity consumption.
This pilot project opens up new perspectives to fully exploit the potential of the smart lighting systems already being rolled out in Brussels. Indeed, an adaptive lighting system could be particularly interesting for areas where the volume of traffic varies substantially and is difficult to predict. For example, around major sports or cultural centres, such as the King Baudouin Stadium, Forest National or the Heysel Stadium. It would also enable a better management of public lighting during specific periods such as the COVID curfew that we experienced this year.
This is the first trial of this kind in Belgium and we are proud to have done it in Brussels, in collaboration with Schréder and the City of Brussels. This is a real opportunity to prepare the smart city of the future and explore the potential of new smart lighting technologies. And this, of course, for the benefit of all citizens in Brussels.