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0 pointsjerf6y ago0 comments

And that's the production during snowfall. Even here in Michigan, the sun shines a great deal more than we literally have snow falling. And if the snow is falling all day, it's going to be a light snow that probably isn't reaching 0.2mW/m^2.

Plus, if I'm seeing the physics here in my head properly based on their description, you can't just stick this out in the snow like a panel and get a consistent 0.2mW/m^2 even under optimal snow conditions. As the snow accumulates on the collector it'll insulate the collector from the rest of the snow. You really want the snow to be brushing the collector and then departing having given up its excess charge, not accumulating on it. Sunlight obviously does not present this problem, since it basically is 100% made out of charge (if you'll pardon the sloppy terminology, asp precision wouldn't really buy anything here), so there's no additional mass to dispose of, just any waste heat issues that may arise.

I'm pretty sure that in real conditions the difference between the two would be another two or three orders of magnitude larger, which is why my other post is so grumpy. It's multiple orders of magnitude obviously not even remotely feasible, to the point it's almost insulting that it was said.

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cogman106y ago

I'm pretty skeptical as well that this is useful for really anything. That energy density is so low that I can't think of a single application where either batteries, solar, wind, or some combination of the above wouldn't both work better and be cheaper.

Just to put a little perspective out there, 0.2 mW/m^2 means that 1 square meter of this stuff would take 600 days in ideal production to match the amount of energy stored in one charge of a single rechargeable AA (~3Wh).

1 clear day, plus a tiny solar cell and a AA and you can get 600 operating days of energy really easily.

And here's the thing, if this thing gets buried, it isn't going to generate electricity. So you have to imagine an environment where the snow is constantly melting, you can get a giant sheet of this stuff, and for whatever reason there is no battery chemistry that would work.

You could say "Well, it would make a good snow detector".. but even that it somewhat silly. Because, again, if it gets buried it won't be detecting more snow. So now you need some complex rigging to keep it from collecting snow so it can register that snow is falling. Why not a camera? A weight sensor? etc. Plenty of pretty cheap and low power equipment can do just this without the additional concerns introduced by this piece of tech.

This thing is useless. Maybe interesting to make, definitely not practical for really any application.