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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.
OK, I am being silly, what the thing should read of instead of
Converts 30% of the Sun's Energy to Electricity
Perhaps what they mean is
Converts 30% of the incident light energy to electricity
After all, the Sun is realeasing a lot of energy, most of which will never hit the Earth.
I'll believe it when I can buy it for a reasonable cost at a store in town.
For years we have every couple of months there a new revolutionary way to convert solar rays to electricity. Unfortunately none has managed to work in the real world except the good old silicon solar cells.
Markus
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
There's this clever thing called power storage. You use your power to reform some hydrogen, and it makes this fascinating device called a battery.
The battery drives your house power needs over night.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
The twin problems are initial expense (which with traditional solar panels is horrible, typically you can expect economic breakeven (at today's wholesale electric prices) in around fifteen to twenty years), and the fact that we can never base our entire power production on (ground based) solar. Solar can be used a lot more than it is, but we can't do everything solar because we don't have a good way to store electricity.
"Mission Accomplished" -- George W. Bush May 1, 2003
Nope. Hydrolysis is close to 100% efficient. Use your brain and think about it. If it was highly inefficient, where is the waste energy going? Water undergoing hydrolysis doesn't get hot. Try it yourself!