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Sunlight in a Tube
Elitist_Phoenix writes "Scientists are developing a technology to save energy by transmitting sunlight into buildings through tubes. Indoor electric lighting is the largest consumer of electricity in commercial buildings. Their new system. called hybrid solar lighting, would reduce this energy usage with fixtures that supplement or completely replace electric light with sunlight, at times when its available. The system is called hybrid solar lighting (Google)."
all the Amish retailers here use the same sort of thing. They can light a supermarket with redirected light during daylight hours, and light up the propane system once the natural light is gone.
Never ask for directions from a two-headed tourist! -Big Bird
This was done in Japan in the Mid 80's.
It was on Beyond 2000 (The tv show.)
The roof of the building had the ends of fiber optics and every desk had a tube-like lamp.
They said it was to freshen up the workers.
The funny part: In the mid 90's I heard a similar building was sued by an employee for skin cancer!
Gotta love it.
The startup phase has its usual challenges, I'm sure, especially finding markets, but the company has become very successful and very well known.
It's called TIR Systems .
(Unfortunately I can't comment on the cited article as it's already slashdotted.)
Parity: What to do when the weekend comes.
This is a pre-electricity invention. The only thing that is new is that they are using fibre optics instead of glass for carrying the light. Here's a LinkTo Shipboard Prisms that was used and patented way back in 1684. A good 331 years ago.
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
for maintaining light levels in combination with 'light tubes' which have been around for a good while, it's nothing new.
I have some controllers from a demolished Kmart store that used automatic control in conjunction with skylights.
Skylights were common in manufacturing buildings constructed in the late 19th and early 20th century.
...back in the 80s, there was a prototype of something like this. It was an extremely high quality glass "light tube" that could actually visually carry light and whatever was at the other end of the tube. The experimental set up they were talking about mentioned a basement lab with six of these around the room. They looked like round windows or portals in the wall, but they actually looked straight up to the sky. You could look in one and see clouds going by. Sounded pretty cool. I think it was featured in The Futurist magazine in 88 or 89.
-"...bad old ideas look confusingly fresh when they are packaged as technology" - Jaron Lanier (Digital Maoism on Edge.o
..and its brand new! well, it was 13 years ago.
..and I know T.I.R. systems has been making light-pipe for at least that long.. not that its not cool, its just sort of, you know.. old.
air and light and time and space
Sad but true. A solar Powered flashlight
--sig fault--
I'm not conversant in the details, but my understanding is that the latest generations of LED technology are making rapid gains. And recently, advances in getting decent white/fuller spectrum light out of them have been made and/or hinted at.
Given that these things can be installed using current systems, and have very low current draw and heat generation, I'm wondering how well what is essentially an architectural design element, with the implications of same from implementation through to building code (including safety features such and firewalling and the like) will be able to compete against LED fixtures and similar.
Please also note that engineers, presumably like the grandparent, would remember to design such filters if only to save their own skin.
I remember playing with lots of fun stuff like that at 3M when I had a brief fiber optics internship there. One of my favorites was a longish (maybe 15 feet) solid plastic tube of high refractive index and a translucent cladding, about a half inch in diameter. (Just a big multimode fiber, really.)
We'd have it all coiled up, point one end at the indoor lights, and point the other end wherever we wanted, and it made a fairly bright spot. It was pretty cool. -- Paul
OpenSource.MathCancer.org: open source comp bio
As an engineer in the lighting field, sorry to tell you this, but light pipes have been around and lighting buildings for over 100 years. Fine on bright sunny days, but not so good otherwise. The main drawbacks have been cost and control. Running the pipes from the rooftop collectors is expensive, much more so than 'standard' fluorescent lighting.
In the early systems, the pipe was a glass tube filled with water. There was near total internal reflection. The pipes couldn't go to far, as the water would attenuate the light.
There are current lighting systems for hazardous areas that put the lamps outside the room and use light pipes to bring the light inside. I believe that a couple of Intel plants use this system in the Fluorine and Silane areas. A few aircraft plants do too. It's too expensive for most uses though.
The systems don't store light well, and can be tough to turn on or off. Dimming is also hard. Still, somebody re-invents it every 15 years or so. Looks like we're on the next cycle.
Still isn't new... I read about this (light fixtures and all) in a magazine devoted to living "off the grid" at least a year ago. i think it's called Natural Living, or something to do with nature, living, and homes...(the magazine that is)
"most of the load on an office hvac system is compensating for the heat put off by the lighting systems."
If you are using a sensible number of flourescent tubes and a reasonable density of human beings and PCs I'd be very surprised if the lighting system was putting out more heat than the combination of humans and PCs. Humans put out around 100W at rest, PCs when being used for typical word tasks probably still put out 50W, a total of 150W. I have a Philips Brightlight with an input of 110W, and even if everyone in an office had one of those even the input power would be less than the heat output from each human and their PC (and the office would be very bright), and the heat output of a 110W flourescent system is less than 110W. Most offices these days use flourescent lighting.
The input power for lighting is an issue, though, and improving natural lighting can cut electricity costs all the same, even if the heat output of the lights is not a big factor. Plus people seem to work better and are more productive with natural light, although the light pipes and so on will test if this is due to having a view or a quality of the light itself.
I don't think this is viable. There is only so much light striking a building. Even if you were to capture it all and redirect it inside, there wouldn't be enough to replace all of the lights, or even a significant portion. Consider a corner office with two walls consisting entirely of windows. The light inside isn't overwhelming, at least not around noon. Now divide this amount of light by 10 or so. Would that be enough to replace the fluorescent lighting in a room? I think using more efficient electrical lighting could give much bigger savings.
No UV-B (or UV-A) rays would make it that far down the tube - most glass attenuates UV quite well.
You'd need to get some stupidly expensive glass (like the kind used in photolithography) to transmit the UV down the light pipe.
I did a quick search on google, and came across this about glass absorbing UV:
"From: James Richmond (Avatar) 15/02/99 12:39:42
Subject: re: sunburn and car windows post id: 1216
As others have said, glass absorbs UV reasonably effectively. I am reminded of a story told by the late Richard Feynman, who was present at the first nuclear bomb detonation. The bomb was mounted on a tower in the desert. Everyone was issued with dark goggles to protect their eyes from the flash as the bomb went off. The goggles were almost opaque, making it difficult to see anything. Feynman figured that the only dangerous thing would be the UV light, and he wanted to get a good look at the explosion, so he sat in a car and watched through the windscreen (without goggles), assuming that the screen would absorb much of the harmful UV. As a result, he probably got the best naked-eye view of anyone present."
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