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Home / Editor's Pick /

In the base of a valley: A town that uses mirrors for sunlight

10:07
7 November 2022

In the base of a valley
A town that uses mirrors for sunlight

RjukanRjukan, known for its perpetual darkness in winter, is located in the bottom of a valley between steep mountains. It only gets sunlight reflected by giant mirrors on the mountain - © picture alliance

While the days across the UK and Ireland are getting noticeably shorter, at least we get natural sunlight unlike a town in Norway that relies on mirrors to bring the sunshine.

Located at the bottom of a steep valley surrounded by mountains, the tiny town of Rjukan does not see sunlight for seven months of the year.

Rjukan was built between 1905 and 1906 by Sam Eyde. It was Eyde who dreamt of a giant mirror in 1913 to provide sunlight for the towns factory workers.

Instead, a tramway, that is still in operation today, was built to give employees and their families access to the sunshine. In 2005, Eyde’s mirror project was revived by Martin Anderson.

Eight years later, three 182-square-foot mirrors controlled by computer-driven motors were installed to bring a 6,500 square foot area of winter sunshine to the town.

The mirrors are able to bring 80-100% of the sun’s light to Rjukan, by tracking the movement of the sun and repositioning themselves every 10 seconds to keep the light consistent.

Although the mirrors are unique, Rjukan’s were not the first. In December 2006, the town of Viganella in Italy’s Antrona Valley celebrated a day of light after a steel sheet was installed to reflect sunlight between November and February.

Weather & Radar editorial team
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