Safety on our roads is paramount, which is why most highways and streets are lit with streetlights at night. But even with newer and more efficient LED bulbs, each of these lights still cost hundreds of dollars per year in energy, and their bright light contributes to what’s known as “light pollution”. But a Scandinavian country is experimenting with a new idea that might solve both problems.

The Norwegian municipality of Hole has installed a string of LED streetlights along its local Highway 155 that normally operate at 20 per cent of power – that is, until a car, cyclist or pedestrian is detected along the route. Using radar, the system will turn on each light up to full capacity as someone along the roadway approaches, then turns the light back down once they’ve passed.

The use of LEDs not only reduces energy use but also makes this system possible, as the light can be turned on or off instantly, rather than needing time to warm up as with more traditional sodium lamps.

Youtuber Bjørn Nyland talks about how the system works and what the savings are, though it’s not clear where he gets his figures.