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500 times the light of a traditional cell? And if traditional cells run at what, somewhere from 7 to 12% efficiency for standard ones?

So he's getting what, upwards of 3500% efficiency? Even accounting for the extra energy of using ultraviolet wavelengths, this sounds a lot like bad math.

Now if he boosted the efficiency to say, three times what we get now? That'd be amazing all on its own.

The best solar cells have something like 30% efficiency at the moment. Even if he boosted it by 1% it would be impressive.

At the moment I've got no idea what he _actually_ did. Obviously, parts of this story are complete BS (e.g. 500 times). Is there something genuinely worthwhile? I haven't read a sufficiently detailed article to figure it out.

Maybe the efficiency only counts the visible radiation? So that the fact that it uses ultraviolent screws up the 7-15% (that is, if you include UV light, its much lower?) That'd be my guess...

Although it is rather low on facts and high on hype.

Yes, I think you're right.

From the article: Most solar cells in use today are either photovoltaic, meaning they harness only visible light, or thermal.

Also: they're engineered to stand freely in three dimensions

So you have panels that catch both visible and UV light, and can do it in three dimensions.

The kid didn't invent it, but he did make an implementation of a relatively new idea.

http://blog.wired.com/geekdad/2008/09/12-year-old-rev.html?n...

Did he actually build one? I haven't seen any indication that he did anything other than "design" one. And it's a lot easier to "design" a nanoscale device than it is to build one.

I mean, I'm sure the kid is smart and all (and no doubt has had some help from his parents) but the media-hype to technical-details ratio here is off the charts.

Yeah, that is what would interest me: how to experiment with Nanotech at home.
> Most solar cells in use today are either photovoltaic, meaning they harness only visible light, or thermal.

Hmmm. I'm pretty sure that's not the definition that I learned.

Is free-standing actually a good thing? It seems to me if you're trying to maximize flux per unit material, you can't do much better than a flat sheet. The only problem is that the sun moves, but it seems like a free-standing array would only get slightly better performance for much greater cost.
From a related article (http://www.katu.com/news/local/28432984.html):

If he is right, solar panels with his 3D cells would provide 500 times more light absorption than commercially-available solar cells and nine times more than cutting-edge 3D solar cells.

So apparently there is some advantage to 3D cells, apparently related to multiple light interactions:

"Regular solar cells are only 2D and only allow light interaction once," he said.

It's still not apparent what the basis is for the 500x light absorption figure. Seems to me that the most meaningful basis is the footprint of the device, but that is not clear from any story I've read on this subject.

It's still not apparent what the basis is for the 500x light absorption figure.

Maybe it is a mis-paraphrase of 500-suns concentration capacity. Alternately, it might only refer to UV.

I don't think the 500 times boast is relative to percentage, but rather the standard of measurement used ...therefore the arguement of 3500% efficiency is a mute point...I'm no scientist, in fact my mind doesn't work even close to that of a scientist, but I paid attention in math class...if you are looking at something that is relatively inefficient as far as potential to begin with, 500 times the standard although very impressive is not unrealistic in the least.
Yes except that would imply that current solar cells have an efficiency of at most 0.2%. Which isn't true.

Maybe they are 500x more efficient in the UV, but in that case it's a meaningless number because the Sun emits very little energy in the UV.