Comments on: STOP PRESS: Pixie dust unsuitable for household lighting

by: A late arrival

Fri, 14 Mar 2008 22:59:38 +0000

kamikrae-z: my favourite few sentences from the Project Eden “it’s good because it’s good” bumf:

The way in which the system applies the technology makes small-scale farming in a confined space economically sustainable, generating the equivalent weight of produce to a ground farm that occupies ten times its horizontal footprint. It therefore presents an entrepreneurial business opportunity to sections of the urban poor who may find difficulties in finding normal wage employment and also in this way suits the lifestyle of the target demographic.

so the guy’s not just smoking it, he’s helping others to grow and sell it! what a fantastic human being!

by: Alex Whiteside

Wed, 12 Mar 2008 23:21:06 +0000

jtwing: Let’s say that your “energetic crank” is about 10N (i.e. enough to lift 1kg) of force over 5cm. That means that a 20kg weight over 200cm is equal to 800 cranks. At a vigorous crank per second, that’s 800 seconds of cranking. These torches seem to get about a 1:15 cranking:lighting ratio, or to put it another way, 4 seconds of cranking gives 1 minute of light. So we’re talking 800/4=200 minutes, or about 3 hours, of hand-torch-grade light from a device which is two metres tall and weights 20kg, and which is dispersing its light over an entire room, rather than in a neat little beam. If you want to boost the light up from hand-torch level (say 4W candescent) to comfortable room lighting (say 40w candescent) you’re going to need to burn up that energy 10 times faster. So you’d have to turn this light over every 20 minutes. Now, looking at Dan’s rigorous analysis, I’m clearly being generous here, but it just doesn’t add up however you look at it.

by: shimavak

Mon, 10 Mar 2008 14:10:34 +0000

I’ve figured it out. All that it has to do to work correctly is to cause the laws of physics (more specifically the action related to gravitation) to be slightly variant in time. If it manages that tiny trick, it need no longer abide by petty laws such as the conservation of energy. Problem solved. I’ll take my Nobel prize now.

Wait. What’s that you say? We can’t seem to find any way to generate a system where our functional mapping our configuration space onto our manifold is not invariant under time? Well, maybe we just need a master’s student from Virginia Tech engineering school to help us come up with a system which could do just that.

If it is all right with you, I will just keep working on other methods while we wait, though…

by: jtwing

Sat, 08 Mar 2008 19:39:31 +0000

Ok, I’m not a physics god. But — what if the motion of the weight was captured by a gearing mechanism that stepped up the slight motion of a heavy weight into very rapid rotations of a small generator? I mean, LED flashlights exist that you can shake to charge, or turn a crank…I opened one of those up (it stopped working) and saw the gears myself. The gear stepping transferred the mechanical energy to a small generator that stored its energy in a watch-sized rechargable battery. I fixed the flashlight, by the way. It’s pretty bright — bright enough to read by, which is all you’d really need in a dark room anyway. Maybe it doesn’t last 4 hours, and maybe the artist’s concept render is hopelessly impractical, but I’m not convinced the concept itself is dead. It certainly doesn’t take me 2 hours of vigorous pedaling to recharge the LED flashlight — just a couple dozen energetic cranks of the handle.

I think something marketable is still there, in the concept. Maybe not at the level the designer envisioned, but still…

by: rcousine

Wed, 05 Mar 2008 18:46:55 +0000

Tristram: few boundaries have ever fallen to devices that push the boundaries of the second law of thermodynamics. This device is the proverbial pretty-but-stupid, and it serves no purpose.

by: tristram

Wed, 05 Mar 2008 09:05:27 +0000

I concur with Alex - ease up. I study architecture, and we like to pursue emerging technologies and explore the way they may possibly influence our designs, and how we can make them work for us. Whilst some of this stuff may still be pie in the sky, it’s nice to see what it can do. I understand your frustration directed at the student, but hey, without people pushing the boundaries exploring, where would we be today?

by: tantryl

Tue, 04 Mar 2008 21:44:27 +0000

I don’t want to promote a hate crime against me… but the Spectrum and original Gameboy looked like what you’d imagine an AIBO shits.

by: Alex Whiteside

Tue, 04 Mar 2008 21:40:01 +0000

Let’s not be too hard on industrial designers. The guys behind things like the ZX Spectrum and the original Gameboy knew what they were doing, and had a good deal of engineering/manufacturing sense. It’s when people couple industrial design with technological crystal ball gazing that it goes horribly, horribly wrong.

by: chrisovenden

Tue, 04 Mar 2008 19:26:04 +0000

I’m sorry - your calculations are quite wrong, as you are failing to take into account the massive increase in the universal gravitational constant which will occur in time it takes to develop these super-LEDs. Haven’t you read “Slapstick” by Kurt Vonnegut?

by: reyalp

Tue, 04 Mar 2008 13:31:29 +0000

The fact that he claimed a very specific number is what really gets me. If he hadn’t done his homework, and just expected it make some light, that would be somewhat more excusable (although still pretty pathetic for masters student)

The claim that it will give out “600-800 lumens” gives the impression that he arrived at this number for some reason, rather than just pulling it out of his posterior.

The weasel worded retraction shows that he’s still clueless, or lying. Ugh.

Or maybe he’s a neutron star dwelling alien living among us ?