Oulu lets walkers choose how brightly their route is lit

Walkers on a path in Pikisaari, Oulu, can choose bright, dim or no lighting, with their chosen setting following them along the route. The experimental system, reported by Yle, uses motion sensors to switch lights on and off as people move.

At the start of the path, three buttons let users select a programme. The sun gives a bright, soft white light tailored to people’s needs; the moon selects a dimmer, more orange light intended to be more considerate of nature; and the star leaves the path dark.

The system lights one point at a time, switching on the next lamp as a walker approaches the previous one. When several people use the path at once, it combines their choices.

The popular shoreline route previously had no lighting. Some users felt unsafe and avoided it in the evenings, while others wanted it to remain dark. Henrika Pihlajaniemi, an associate professor at the University of Oulu who specialises in lighting, said the project carefully considered users’ wishes.

Balancing safety and darkness

Pihlajaniemi said users had responded positively to the new lighting. When people want to preserve some darkness, she said, lights must not cause glare.

More lighting does not necessarily make a place safer, she said. In bright light, the surrounding darkness can appear black because the eye, adjusted to the light, struggles to see beyond it. Dimmer lighting can make it easier to distinguish things around the path.

Artificial light at night can disturb animals and plants and affect people’s sleep rhythms. Pihlajaniemi said the quality of lighting matters more than its quantity.

International project includes five countries

The Pikisaari installation is Finland’s pilot in the Art of Darkness project, led by Pihlajaniemi. The project is testing lighting approaches that leave room for darkness in cultural heritage settings in Finland, Denmark, Estonia, France and Italy. The route also passes the ruins of an old steam sawmill, which have been lit.

Oulu’s recently published city-centre vision for 2040 also calls for the city to plan for darkness, control light pollution and prioritise lighting quality over quantity.