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Norwegian Town Using Sun-Tracking Mirrors To Light Up Dark Winter Days
oritonic1 writes "During their long, cold winters, the Norwegian town of Rjukan doesn't enjoy much by way of daylight—so the town (population 3,386), installed three giant sun-tracking mirrors to shine a steady light over a 2000 square foot circle of the town square. From Popular Mechanics: 'Call it a mood enhancer. Or a tourist attraction. But the mirrors, which will be carried in via helicopter, will provide an oasis of light in an otherwise bleak location at the center of the 3500-population town.
Three mirrors with a total surface area of about 538 square feet will sit at an angle to redirect winter sun down into the town, lighting up over 2150 square feet of concentrated space in the town square. A similar idea exists in the Italian village of Viganella, which has used brushed steel to reflect light since 2006.'"
It didn't work out well in Lord Parker's 'Oliday.
...I live along the equator where our days and nights ar "equal" throughout the year.
Trouble is that most Europeans I have met on my travels think it's hot hot hot at the equator, which isn't the case. In fact, their summers, which are responsible for some deaths among the elderly and young ones, are way hotter than the hottest day at home.
When I say this, they won't believe it until I remind them that we are at a higher elevation which is cooler...just like the clouds.
... a 2000 square foot circle of the town square ... ... about 538 square feet ... up over 2150 square fee
This is slashdot science ?
Besides, the slashdot summary is ambigous : it mentions a population of 3,386, but in which unit ? Number of legs ?
Because a balloon would not direct much of the light into the town, but basicly everywhere. Sun light is (nearly) parallel, and to reflect it into a town, you need a plane reflector. Only a small part of the balloon's surface would reflect the light into the desired direction.
Some people might think it a curse. To them it is home.
much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
Rjukan is also the site of the museum of industrial labour, which is located in Vemork. In addition to being a very early heavy water plant which was sabotaged by the Resistance during the second world war to hinder the Nazi nuclear bomb project, it also currently hosts an exhibit of what is probably the world's only remaining Univac 1108 mainframe.
toresbe
Don't say that - we love the Norwegian summer. I think most people feel it's the best day of the whole dang year!
(for those who might not have picked up on it: this is largely a joke.)
toresbe
They did this same kind of mirror thing in Rattenberg, Austria a few years back.
Now we could hack into the controller and reprogram it to direct the sun to a single point and voila! Instant death ray. Might help with the tourist problem.
How does this mirror compare to installing full spectrum lamps to light up the same 2000 sq ft area? Lights could provide extended "days" during the winter months, and could be solar powered from the same mountaintop that houses the mirrors when the sun is out.
The article states that the project cost is only about $850k, mostly provided by private donations. The tracking motors will be solar-powered. So, for a modest outlay of capital today, they get ample, high-quality, non-polluting light for next to nothing for the life of the system. Any idea what a stadium lighting system costs? How about the cost of electricity and replacement bulbs to keep it operating for 8-16 hours a day, five months out of the year, for decades? Mirrors on a heliostat is not a boondogle, it's proven technology. And, in this case, probably cheaper than the alternative.
https://en.wikipedia.org/wiki/Concentrated_solar_power
What part of "Tourism's an important part of the local economy" was so difficult to understand?
That being the case, people are already visiting the town. In fact, if you could have been bothered to just search some info about this particular town, you'd know that the tourists visited that area for a few centuries, actually before the town even existed, because of the beautiful nature. Besides, the town belongs to the Telemark community, and Telemark basically stands for winter sports.
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
http://www.imdb.com/title/tt0059263/
http://en.wikipedia.org/wiki/Vemork
Some trivia:
The Vemork factory was placed exactly there because of the optimal conditions for producing hydroelectric power.
It started out fixing nitrogen for fertilizer, but later on was converted to produce heavy water. This is what Hitler needed for the production of a nazi A-bomb.
Both nitrogen fixing and production of heavy water is extremely power consuming.
The factory (and Rjukan city itself) lies so deep within the valley, the Allies considered it near impossible to bomb. They tried, once. The production was considered so important the Allies tried 4 sabotage operations against it.The most famous one, Operation Gunnerside, was made as a film, starring Kirk Douglas: The Heroes of Telemark.
PS: Sorry about the links on top, using a shitty mobile browser.
If the mountain is a 2km away the reflection from the mirror is going to be very broad indeed. The sun is a half-degree across, and half-degree times 2km means that the edges of the mirror beam will be about 20 meters wide, nice soft edges and not the harsh ellipse shown. The ends of the ellipse will have edges more like 100 meters wide.
I love Mondays. On a Monday, anything is possible.
... who thought, after reading the title, that they were going to put mirrors into space? Giant mirrors in geostationary orbit focussing the light onto a small Norwegian town? Now that would be a tourist attraction.