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Solar Window Panes
Val42K writes "Now, those windows that allow glare onto your computer screen can be useful. They will provide power to your computer, air conditioning and other useful necessities. Energy conversion rates are 'way more than 50 percent'."
This looks pretty cool, but reading through the article I don't really see exactly how much eletricity these will produce per window. Will they make a significant dent in the power costs for a typical household? The cells may only be a quarter each, but how much will it cost to embed them in the windows and collect the power?
Twenties Retirement
Check out the pictures to the left of the main story. There's a noticeable difference in light intensity between parts of the window with clear glass and those with the embedded miniature solar panel, leading to a mosaic light pattern. This sort of thing is fine (and maybe even artsy) for an office foyer, but won't be widely adopted in office windows (which make up the majority of downtown buildings) because it's horrible for reading or working in. Your eyes can't tell if they should adjust for the bright or dark spots.
The bold print giveth, and the fine print taketh away
I don't believe this story for a second. Not a bit.
For decades I have been folowing solar cell technology, absolutely salivating at the promises that efficiency rating would soon rise above 15%.
Well, I've given up. I've read shitty pie-in-the-sky stories like this almost every year for the last 25-years.
Now, if someone on Slashdot tells me that they bought these +50% efficient solar cells in Home Depot, that's when I'll get excited. Like I'll get excited when Chevrolet markets a flying car or my city puts a nuclear fusion power plant into service.
Chill out guys, it ain't real 'till it's real.
--Richard
Do a Google search on solar cell window and you quickly realize that this is an old idea.
Absolutely. Very old idea. However, do a Google search on commercially available products in this space and you quickly realize that this an old idea that hasn't really been commercially developed. You could chalk that up to the dangerous imprecations of the 'old girls' network, but I think it's just a problem that hasn't been solved yet in a cost-effective manner. Which is why money is still being spent looking into it.
But what's important this time I guess is that it's a woman who "discovered" the idea.
I don't see why you would conclude that. I can think of two reasons this article might be important:
Note that those two options are not mutually exclusive.
Bullshit. Current conversion rates are about 18%, and haven't changed much in 20 years or more; they've slowly managed to squeek out more and more power getting up to the current 18-20%, but nowhere near 50%. Let's put this in perspective- it would be like someone claiming they could get 100mpg in their car, and "easily 200mpg".
The bullshit-o-meter goes off the scale at the claim they can get "100%"- and there's one very simple, indisputable reason; the glass itself blocks a significant amount of energy- ESPECIALLY at a low angle of incidence, where the outer glass is going to reflect a large percentage of the light hitting it. The modules inside the window may pivot, but the outer glass doesn't.
The bullshit-o-meter EXPLODES at the nice little bit about how they won't discuss specific energy conversion rates in detail. It doesn't help that this is being published in Science for People Who Think They're Trendy(aka Wired). Ring me when she's published results in Nature or (gasp) a professional journal.
Oh, and if I wasn't pessimistic enough :-)...if this actually DOES pan out...just wait until you see the price tag on 'em, because I'm sure she's going to patent absolutely everything out to wazoo, and one company will get exclusive rights. It'll also be years before we see 'em, as said company will want to protect its investment on current solar panel technology...
Please help metamoderate.
> For the researcher to generally state 'way more than 50%' rings alarm bells in my head.
I'm with you on this one, as it seems highly suspicious that this group has been able to produce ultra-efficient solar cells. Beyond that, I don't see the point of integrating these panels into a window - that just seems complex, unnecessary, and certainly has to be more expensive than a regular window paired with a stand-alone solar cell.
My take is that this idea will not succeed. Nobody will be willing to spend the money to replace the windows in existing buildings, and future construction will probably not be interested in spending more money for integrated solar-window things without some reality to back up these efficiency claims.
and many places aren't suitable for hydro generation. and many more places lack fossil fuels. so?
when it comes to alternative energies, we aren't looking for one silver bullet. a solid energy programme will rely on a diversity of generation methods as well as consumer and industrial-level conservation measures. when it's windy, use wind. when it's sunny, use solar. when neither is available, fall back on hydro or (god forbid) coal. and, of course, conserve, conserve, conserve.
the last time we had a grand-unified-energy-solution it was "too cheap to meter" nuclear power.
oops.
2 1337 4 u!
I've done a great deal of research on the topic of solar energy and have a pretty good understanding of physics. To the average person, this article sounds wonderful - super efficient solar panels, a total breakthrough! To me, it's pretty easy to see this article either grossly misquotes the researcher or the researcher is completely crazy.
From the article: "Ultimately, Dyson is confident her team's solar cells can reach nearly 100 percent efficiency -- compared with typical solar panels' conversion rate of less than 20 percent."
100% sounds great. Except they forgot that glass absorbs/reflects a minimum of 10% of the light, much more at non-direct angles. And that getting any semiconductor (solar panel) surface to absorb all light hasn't yet been possible - assume another 15% is lost here. And of course, to be able to actually see through the cells (they're "translucent"), we'll assume 20% light transmission. Then you need to think about things like entropy and expect a nice loss in this process, we'll be generous and figure 10% loss.
Just adding the percentages shows 55% efficiency by simple addition. And this is with everything ideal. And now consider that the _best_ solar experiments have approached, under super-controlled situations, 40% efficiency.
And top all this off with no demonstration of the product itself and no details on their technology, it's another vaporware article.