Slashdot Mirror
Breakthrough Efficient, Paintable Solar Cells
An anonymous reader writes "A new solar cell material has been discovered that converts 30% of the sun's energy to electricity." Here's another solar news story. These new cells can harness infrared light which is why they are so much more efficient.
It must be expensive.
So if I spray that on my tinfoil hat and run a couple of leads to my laptop I could have unlimited power!
Trolling is a art,
converts 30% of the sun's energy to electricity.
We are gonna need all that electricity because if the sun is 30% smaller than it was before this thing our heating bills are gonna go way up!
I tried for 5 years to come up with a clever sig...only to realize that I am not clever.
Does this recharging unit make my ass look big?
If you check the original press release, you'll notice UT says the 30% efficiency might be realized "with further improvements in efficiency". The reporter for CTV missed that little nuance.
Sweeping statements should never be made.
Slashdot does this every once in a while - announce some tremendous new solar energy technology. Folks, it's not easy to get 30%. And even if you do, you haven't won the war. The best, most expensive cells can make those ranges, but they are not something you can put on the assembly line.
I did some research into Cu(In,Ga)(S,Se) thin film solar cells, which have long been a promising material for this type of application. I don't claim to know all about the various options out there (there are a lot of them) but I feel I can safely say there just aren't any magic bullets to this problem. Let me give you some idea of what has to happen.
a) You need a cell with a high enough efficiency to make the power it can produce worth the hassle of installing it. This is hard and the focus of most solar cell research.
b) Even if you GET that cell, you have to be able to make a LOT of them. Cheaply. Very cheaplly if you want to compete with grid power.
c) These materials have to stand up to long term punishment, intense thermal cycling over the course of day and night temperature shifts for twenty years, etc.
d) You have to install the supporting systems - either connect it to grid, get a large energy storage array (i.e. batteries) or both. If you want a battery based local storage system that gets expensive, all by itself.
e) You need to build the industrial support required to make large scale deployment both possible and cost effective. Si, the current dominant material, has a lot going for it because a lot got learned over the course of decades of semiconductor technology. Those tools are somewhat applicable to Si. If you want to use something totally different (i.e. a thin film) you have to make all the gear more or less from the ground up. That's a big initial capital investment for a dubious return.
f) If you want flexible solar cells, you have a whole new set of problems to handle/test, like how the cell performs while being folded repeatedly in different temperature conditions, creased, beat up generally, etc. And flexible cells are a bit of a specialty market - the military likes the idea, sports folks like it, but for large scale fixed installation use (i.e. where bulk production would happen) flexible isn't all that critical. (Although it is nice when it comes to things like roofs withstanding hail storms, but apparently regular ones don't do so hot there anyway.)
g) THEN, after you solved the problems of cost effective production, storage, retrofitting of housing, etc. etc. etc. you have to convince people it's worth the trouble to install it. And I remind you this is the land of the SUV, so I wish you luck with any marketing effort that can't say "We're cheaper than grid power!". Grid power is CHEAP. VERY cheap. It's a really really hard target to hit, and the solar cell technology available today just isn't there yet. There are lots of "potential" 30% configurations - all you need to do, in theory, is have a multijunction device with the right bandgaps. But let me tell you, it ain't easy.
Now, somebody might make a sudden miracle discovery of a cheap 30% cell material. Such things do happen. But I'll want to see a lot of (reproducable) proof, and peer review, before I'll buy it. It's good advertising to claim high performance, but I'll be impressed when someone goes through the nitty gritty and comes out with a viable product.
"I object to doing things that computers can do." -- Olin Shivers, lispers.org