Fiber Optics Bring the Sun Indoors

Sterling D. Allan writes "Fiber optics transmit light, so why not take the light from outside and transmit it inside? According to an exclusive story at PESN, that is what Tennessee company, Sunlight Direct, is now doing. Their 4-foot-diameter solar dish will light 1000 square feet inside -- minus the harmful UV rays -- rendering a more natural lighting feel, which can be hybridized with florescent and possibly LED lighting to provide a constant light level, though the tone changes with the level of light outside. The GPS-based sun-tracking mechanism uses very little energy. Now you can save electricity, cut on heat emissions by incandescent, and improve the feel of your work environment. Beta testing began in June. Product expected in the market in 2007."

These have been around for a while...

[EnronHaliburton2004]

I remember seeing pictures of these on Japanese office buildings in the early 80s. They were called "Sunflowers", and they were mostly prototypes I think, and had a honeycomb [si.edu] set of collectors which piped the sunlight into the building.

That's why it's called 'natural light'

[maxrate]

There is a reason why it's called 'natural light', because it's natural, not artificial.

I moved my office from a building where we had NO windows. Productivity has gone up tremendously. We don't feel as worn out at the end of the day, and we don't feel like we missed out on anything.

I saw this on the Discovery channel, and it's fantastic for commerical space as you can distribute 'natural' light all over the office where windows can't be located. It saves on energy use as well. As yes, there are UV filters.

I wish it was a little more affordable, i'd do it in a heart beat.

Re:Photonic Storage?

[TigerNut]

The speed of light is 300 million meters per second. As long as your definition of 'a while' is in the millisecond range, you're in business.

The 'infinite light trap' is an interesting notion, but since the mirrors would absorb a small fraction of the incident energy with every photon reflection, you wouldn't be able to store a lot of energy until things got really hot.

One thing that might work is to trap photons inside a slow-light crystal, but I think that conservation of energy would still have to apply, and you'd quickly find out that collecting solar power in a small volume gets things HOT.

It does...

[KingSkippus]

The article specifically says that it does:

The system's 48-inch primary mirror concentrates light into a secondary mirror, which strips away the infrared and ultraviolet components, and directs the visible light into the receiver.

As for the solar panels, I would think that they'd be a lot more expensive. (Disclaimer: I haven't actually checked.) The systems I've seen require large banks of batteries to store power, and there are a lot of expensive system components.

One nice thing about solar lighting is that there's really not much else other than a mirror and a bunch of fiber optic cables. It's a pretty simple system made of relatively cheap parts.

Also, one of the selling points of the company's Web site is that the lighting is all natural, not artificial, which is supposedly preferable for happy attitudes and such.

Of course, not having any lights at night or on cloudy days would totally suck. The article mentions that the system can be integrated with supplimental artifical lighting. Perhaps a combination of solar panels and solar lighting would be the best system if one wants cheap, eco-friendly lighting that is also mostly natural for happy attitudes.

Dupe + Old Story Anyway = You Suck?

[loggia]

This was posted on Slashdot a few weeks ago.

And many posters (including me) pointed out that sun pipes have been around a long time.

Himawari

[Anonymous Coward]

Here's the homepage of the Japanese company that did this almost 20 years ago:
http://www.himawari-net.co.jp/e_page-index01.html [himawari-net.co.jp]

Re:Old News

[sirket]

It's not worthless. The system works amazingly well. The problem? Cost. Fiber optics and installation were not cheap- at least when the Ark Mori building was built. These days however? Costs have plummeted and energy costs have risen. It is an ideal time for this system to make a comeback. And the light quality? Amazing from what I heard from a friend who visited the building while she was working in Japan.

-sirket

Geomagnetic reversal happens, but aliens don't

[SuperBanana]

she wrote a whole article about how we're all doomed because of the impending Magnetic Field Revesal

a)the earth's magnetic field does reverse every so often, b)we're overdue (by a huge margin) and c)we probably would be slightly fucked, because during the flip, we'd have no protection from cosmic and solar radiation.

NOVA [pbs.org]

Wikipedia Article on Geomagnetic Reversal [wikipedia.org]

As for the aliens- yep, she's off her rocker on that one, but don't throw the baby out with the bathwater.

Re:Photonic Storage?

[deglr6328]

In short. No. The trouble is in the absorption of photons by your reflective trap. See, even the most perfectly reflective surfaces we're capable of making (~99.999% reflective) are not good enough to do this. There is a technique for measuring the reflectivity of these (VERY) expensive mirrors called cavity ring-down where a laser pulse is injected into a cavity created with a highly reflective mirror and you watch how quickly that light pulse decays and this tells you very accurately the reflectivity of the thing. After only some tens of microseconds you are left with mere fractions of a percent of your original pulse. So in short, even with super reflective walls, your photon storage unit will still very efficiently convert those initial photons to heat in short order.

Re:Old News

[pchan-]

My parents have one of these in their kitchen. Works very well, actually, and the light is very white and pleasant. This is much better than a skylight for several reasons. The first is that the light is not directional, but very diffuse, giving good light all over. Second, you don't really have to clean the dome. Third, it goes through your insulation, and is sealed at both ends, keeping a decent separation of you from the hot/cold. Finally, it's pretty small and easy to install yourself if you're handy with a caulk gun. I'd definitely get one of these if I had a house.

I've seen the Mori Building solar collectors (on TV). The idea was that they could transport natural light into areas of the building that are not near windows, and that sunlight seems to make people happier. And they didn't need GPS to do it because the sun is, y'know, fairly predicable.

Re:Very cool

[mboverload]

As seen with the need for repeaters fiber does not transmit light even close to far enough to make that practical.

Re:Old News

[starfishsystems]

Ordinary reflective materials like mylar are quite lossy. That's not a big problem when the light path is fairly straight and only a few meters long, which I expect would be true in many residential applications. But if you want to go long distances or direct a lot of light energy around corners, you would need more efficient transmission.

But you're right that light fibers aren't exactly big news for illumination. And they're not the only medium with low transmission losses, either. About 20 years ago, a friend of mine started up a company called TIR Systems [tirsys.com] to commercialize a light pipe technology that he developed in grad school. It works approximately like optical fiber but the prism light guide is much larger, and also requires less elaborate manufacture. The early materials that I saw were pressed out of large slabs of acrylic or something. At any rate, it seems much better suited to architectural application than bundles of optical fiber. And that's old news too.

Re:Old News

[Ray Radlein]

Never mind newcomers to the concept like the Aki Mori Buidling; if you want a real "Old News" version of it, look no further than Frank Lloyd Wright's Johnson Wax Heqadquarters [wikipedia.org], finished in 1939, which used Pyrex tubes to bring light inside the building [bc.edu].

Of course, as (almost) always, Wright's vision was just a wee bit ahead of the materials science of the day; the whole setup used to leak like crazy. But what the hell -- it sure was gangbusters back in 1939, when the future was invented.

Re:Geomagnetic reversal happens, but aliens don't

[Trepalium]

Yes, we're overdue, but most scientists say that a reversal would take hundreds or thousands of years to finish. In fact, we may be in the midst of one right now (the magnetic field has been weakening for a couple thousand years now). But it's not like anyone will wake up tomorrow and find that compasses, and everything else that is affected by the earth's magnetic field suddenly don't work.

Some people also say we're supposed to be overdue for a glacial period since we're still in the middle of an ice age. I don't have the energy to worry about all these things I can't change even if I wanted to. And none of these things is likely to happen in my lifetime (or anywhere near my lifetime). I think I'd rather focus on things I can affect.

Re:Geomagnetic reversal happens, but aliens don't

[Lars T.]

c)we probably would be slightly fucked, because during the flip, we'd have no protection from cosmic and solar radiation.

Maybe not [newscientist.com].

Re:During the cold war...

[YrWrstNtmr]

The soviets used a pencil.

Riiight. [snopes.com]
"NASA never asked Paul C. Fisher to produce a pen. When the astronauts began to fly, like the Russians, they used pencils, but the leads sometimes broke and became a hazard by floating in the [capsule's] atmosphere where there was no gravity. They could float into an eye or nose or cause a short in an electrical device. In addition, both the lead and the wood of the pencil could burn rapidly in the pure oxygen atmosphere. Paul Fisher realized the astronauts needed a safer and more dependable writing instrument, so in July 1965 he developed the pressurized ball pen, with its ink enclosed in a sealed, pressurized ink cartridge. Fisher sent the first samples to Dr. Robert Gilruth, Director of the Houston Space Center. The pens were all metal except for the ink, which had a flash point above 200C. The sample Space Pens were thoroughly tested by NASA. They passed all the tests and have been used ever since on all manned space flights, American and Russian. All research and developement costs were paid by Paul Fisher. No development costs have ever been charged to the government. "

Re:Old News

[r00k123]

Hehe.

"caulk gun"

Hehehe.

Re:This is new?

[Baby Duck]

Yes, the Japanese called this "piped sunlight" and was featured on the early 80s TV show "Ripley's Believe It Or Not" hosted by Jack Palance.

It was also used to grow gargantuan tomato plants. Like bigger than twice my house.

Re:This is new?

[Baby Duck]

Ah, yes, I should have googled this first.

Particularly interesting experiments were conducted by the late Dr. Kei Mori of Kao University in Tokyo. Dr. Mori raised plants under special light that filtered out IR and UV radiation. His unique process of fiberoptic sunlight collection and transmission, called "Himawari Sunlighting", is now marketed worldwide. At first Mori feared the filtered light would be detrimental. But after extensive experiments he claimed it could promote healing and "because the ultraviolet is blocked, this sunlight does not fade fabrics or damage skin." (Gilmore, Elaine, "Sunflower over Tokyo," Popular Science, May 1988, p. 75.) One long-lived tomato plant was grown in a special nutrient-rich solution to be exhibited at the Japan Expo '85. Under piped sunlight and controlled atmosphere, this tomato tree grew over 30 ft high and yielded more than 13,000 ripe tomatoes during the six months of the Expo! (Hiroshi, Koichibara, "Tomatomation," UNESCO Courier, March 1987.)

Read More ... [genesispark.org]

Re:During the cold war...

[chamblah]

At least your chosen name suits you.