An innovative street lighting project that saves energy by only casting as much light as is needed has been awarded the Swiss energy prize for 2018.

The Swiss Federal Office of Energy awarded the annual Watt d’Or prize to the Zurich electricity company EKZ for a project it has been trialing in Urdorf for the past year.

The federal office said the system allowed the street lighting to be ideally adapted to best serve the needs of the local population while also taking into account animals active at night, the Tages Anzeiger reported, quoted by thelocal.ch.

It also enables an energy saving of up to 70 percent.

The 1km main road passing through Urdorf in the canton of Zurich was fitted with 27 special street lights that can adapt to the traffic levels.

Optical sensors measure the level of traffic and a central computer calculates the right amount of light and transmits this to each of the 27 street lamps.

The level of lighting is then increased or dimmed.

“The aim is for optimal lighting everywhere and at all times,” the paper quoted project leader Jörg Haller as saying.

The adaptive lighting system using LED lights is thought to be unique in Europe.