Rjukan, the city in Norway illuminated by giant mirrors

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2 years ago Nathan

The picturesque industrial town of Rjukan, in the municipality of Telemark, Norway, sits in a deep-cut valley at the foot of the mighty Gaustatoppen mountain.
It’s pretty, that’s for sure, but the steep slopes of the surrounding mountains completely block out the sun for half the year, leaving this thriving community of 3,400 souls in permanent shadow from September to March.
Yes, the rays of the sun lingering temptingly on the mountain sides, but never reaching the town.
However, all changed when one resident decided to illuminate the town square using three giant mountaintop mirrors.

Now for six months each year the rays of the sun blocked by the surrounding mountains never reach the small town directly except for a strange pool of light on the town square, a spotlight-like circle of sunlight spilling over some 600 square meters and a semi-circle of wooden benches.
This is all thanks to the Solspeilet, literally sun mirror, a computer-controlled array of three giant mirrors that direct sunlight down from the mountaintop.
Located 450 meters above the town, the mirrors are programmed to move with the sun, readjusting every 10 seconds to keep a constant beam of light reflecting down upon Rjukan.

Installed in 2013, the Solspeilet was the idea of Martin Andersen, an artist who had moved to Rjukan in 2002, but soon found the lack of sunlight depressing.
He heard about a partially covered sports stadium in Arizona that was successfully using small mirrors to keep its grass growing, and he also learned how heliostat were being used to reflect concentrated beams of sunlight to heat steam turbines to produce electricity. The following year, the Italian town Viganella successfully installed a similar sun mirror to reflect sunlight into the village.
Viganella, just like Rjukan, is located in a valley where the mountains cast long shadows for three months in the winter.
Thus he managed to convince local authorities that this pool of pure sunlight was necessary for the townspeople.

But the idea wasn’t actually new.
About one hundred years earlier, Sam Eyde, the town’s founder and local leader of industry, who started a fertilizer factory there, also had plans for a sun mirror.
However, he lacked the technology to implement his plan. Instead, he built the Krossobanen, an aerial tramway that could take the residents of Rjukan, most of whom were employees of his Norsk Hydro company, from the town up into the sunlight on the mountains.
Thanks to the sun mirror, however, locals no longer need to ride the Krossobanen 265 meters up the mountain to get a dose of sunlight, although the cable car system does is still in function and remains popular and functional still today transporting thousands of people to the mountains every year.
At first, not all residents were convinced that the sun mirrors were worth the money, as the investment cost five million NOK at the time (about $851,000), money that many thought could have been better spent.
Either way, with the help of public investment and private sponsorship, most of which came from Norsk Hydro, the company founded by Sam Eyde, Andersen raised the amount of money that allowed the town to complete the project.
It was nothing more than a gimmick, some argued, a lot of cash for a little slice of sun.
But many of these critics soon came around when the mirrors helped put Rjukan on the map.
In fact, the international attention helped provoke a new wave of tourism, and people still visit Rjukan to try the light of the Solspeilet.