Fiber Optics Bring the Sun Indoors 377
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."
Very cool (Score:5, Interesting)
Old News (Score:4, Interesting)
Not that new under the sun (Score:2, Interesting)
www.solartube.com comes to mind right off the bat...
Skylights are nice (Score:5, Interesting)
Nowadays, they've got a nice system where the light is guided through a reflective tube that can be directed to any room in the house.
http://www.solatube.com/ [solatube.com]
It was only natural that the techonology would progress to where we are splitting the sunshine into fiber optics and redirecting them all over the house. However, 2007 is a pretty long way off for what seems to be a relatively simple application of existing technologies.
Photonic Storage? (Score:5, Interesting)
Maybe a nanomaze of fiber, a few wavelengths in diameter, twisting its way around inside a cubic centimeter? If such a "photon trap" were millions of meters in length, it might be able to absorb photons for a while, before the first ones trapped finally made their way around the loop to the surface, during which time the trap could be closed (with a mirror, cycling the photons through the circuit until it was opened again. Or maybe an input window that's mirrored only on the inside, trapping photons continuously, until another mirrored facet is removed. Or a spiral maze of MEMs mirrors which send light around the cycle, until one is tilted away from the cycle, towards the output.
Is there any kind of work on "photonic storage"?
Re:Filter the UV rays (Score:3, Interesting)
Re:Photonic Storage? (Score:5, Interesting)
The author also wrote about alien technology! (Score:5, Interesting)
So take this article with a big grain of alien-free salt.
Arcology lighting (Score:3, Interesting)
Just a random thought on an application.
Re:Very cool (Score:5, Interesting)
Re:Photonic Storage? (Score:2, Interesting)
Until then, is there any way to just charge a photonic crystal with 4m^2 sunlight all day, and get 1m^2 sunlight all night? Only 75% decay over 12h?
Elevators (Score:3, Interesting)
The main benefit would be the lessened heat dissipation. I've been in far too many elevators that have what seems like way too many incandescents in the roof that make the elevator very hot, especially this time of year.
Let's do some maths. (Score:5, Interesting)
Looking at my latest electricity bill, I'm charged 13 cents (Australian, roughly) per kilowatt hour. Ten dollars is 77 kilowatt hours; that's equivalent to running one of those things for 5,000 hours (again, roughly).
Working period is 8 hours a day, five days a week -- forty hours a week. 5,000 hours is therefore 125 weeks, or about two and a half years. Multiply that figure by the number of square feet a standard bulb can illuminate (it'd be, what, about 50 square feet at a guess?), and you have a break-even point of 125 years.
If they're replacing incandescent bulbs (which use four times the electricity), break even comes down to about 30 years.
Points to consider:
- My pricing for electricity is residential rates. Industrial and commercial rates are probably different. Anybody have solid figures?
- I'm guessing with the 50 square feet per bulb. If a bulb can light more area, the time to breakeven increases accordingly. If less, it decreases.
- Businesses typically use fluorescent tubes, not bulb replacements. I don't know how much energy those use, nor how much area they can light.
- Does this price include installation? If not, there's an added expense before break even is reached.
- You'll also need other lighting to supplement this system on badly overcast days, and at night, reducing the payoff.
The price will have to drop a bit based upon my back-of-the-envelope calculations before this becomes viable. If anybody has better figures than the ones I've given, please, speak up -- I'm genuinely curious. In particular, I don't know how much electricity costs a business in the USA; that is the single biggest factor in determining payoff time.Re:Photonic Storage? (Score:3, Interesting)
One good idea (for the whole light-pipe business) would be to take the UV energy that is reflected or filtered, and use it to energize a fluorescent radiator whose output could then augment the visible light collected by the system. Since there are some fluorescent materials with extended decay times, that might buy you some 'charge' time.
Re:Photonic Storage? (Score:5, Interesting)
This is a geometric problem which has been solved by mathematicians. The light trap looks like an egg with part of the lateral wall removed. The "egg" itself is made of portions of a paraboloid and an ellipsoid. The light gets trapped in the ellipsoid, bouncing on a trajectory ever closer to the major axis of the ellipsoid, i.e. the line joining the foci.
This is new? (Score:2, Interesting)
Re:Very cool (Score:2, Interesting)
Wouldn't you do the Julian May thing and just build huge evacuated tubes with mirrors every few kilometres to account for the curvature or the Earth?
Is there a gas we could use instead of a nasty vacuum?
Re:Photonic Storage? (Score:5, Interesting)
Seriously though, there is no possible way to do what you want using mirrors, because there is no perfect mirror. And saying 'fiber' just means using mirrors (fiber reflects light down its length). What you want would be a lossless (or really damned close to lossless) method of focusing light: that method is gravity. One could conceive of (probably not implement though) a system where you had a perfect gravitational loop (e.g. by moving stars around to suit your purpose) and one could add light into this loop by aiming a laser properly, or a deft us of mirrors (you would only use the mirror for one reflection, gravity does the rest).
The reason this wouldn't REALLY work is that while light (photons) doesn't/don't have mass, it has momentum. So changing the direction of a whole boat load of photons would in fact wreak havoc on the perfect circle of a gravity well you created (the stars would be moved). I think. That, and good luck moving stars around
So, short answer to second paragraph: Won't ever work. Cool thought though.
Short answer to first paragraph: It's called a black hole
But then, if we have a stable black hole to play with, we certainly would have no need of storing photons
Cheers
Re:Geomagnetic reversal happens, but aliens don't (Score:5, Interesting)
I can prepare for Magnetic Field Reversal like I can prepare for a really big comet-earth collision. I'd rather focus on the more likely tangable problems.
In my experience, Magnetic Field Reversal is a story mostly used by crackpots to sell survival equipment.
I went to College with people who fled to the hills to prepare for the eventual Magnetic Field Reversal-- that was supposed to happen around year 2000 (I told them that magnets don't follow the Christian calendar) Now it hasn't happened, so they moved the date to 2012, which is a signifigant date on the Mayan calendar.
In High School, I knew people who stocked up on supplies to prepare for Revelations, which they thought would start in 1996.
I'm not kidding.
Not new to me (Score:1, Interesting)
The collector mirror... you guessed it, a big ugly satellite dish that he bartered to have chrome plated, and a DIY sun tracking system that is powered by the sunlight it tracks!. The system provides more than enough light to light up his place, though it is a bit weird when clouds pass overhead.
At night and on stormy days he uses stored energy from solar panels. He used to use a 12 volt system, now he uses compact fluorescent bulbs and inverters. His entire nightime lighting system (every light in the house) uses less than 300 watts, where before he calculated it to use almost 800.
Re:Very cool (Score:2, Interesting)
Solar Energy: (Score:3, Interesting)
And that's from a licensed dealer who's making money hand over fist as the panels can be had for around 600$, the connection equipment and batteries add up.
Now lets reject the IR into a water-tube to capture that as surplus energy too and we've got a better system that costs less...
Re:no (Score:2, Interesting)
Re:Geomagnetic reversal happens, but aliens don't (Score:3, Interesting)