IBM Research Unveils Breakthrough in Solar Farm Technology -"Liquid Metal" at the Center......

MarketWatch ^ | May 15, 2008 | Steven Tomasco IBM

[Ernest_at_the_Beach]

"Liquid Metal" at the Center of IBM Innovation to Significantly Reduce Cost of Concentrator Photovoltaic Cells

ARMONK, NY, May 15, 2008 IBM today announced a research breakthrough in photovoltaics technology that could significantly reduce the cost of harnessing the Sun's power for electricity.

By mimicking the antics of a child using a magnifying glass to burn a leaf or a camper to start a fire, IBM scientists are using a large lens to concentrate the Sun's power, capturing a record 230 watts onto a centimeter square solar cell, in a technology known as concentrator photovoltaics, or CPV. That energy is then converted into 70 watts of usable electrical power, about five times the electrical power density generated by typical cells using CPV technology in solar farms.

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The trick lies in IBM's ability to cool the tiny solar cell. Concentrating the equivalent of 2000 suns on such a small area generates enough heat to melt stainless steel, something the researchers experienced first hand in their experiments. But by borrowing innovations from its own R&D in cooling computer chips, the team was able to cool the solar cell from greater than 1600 degrees Celsius to just 85 degrees Celsius.

[Ernest_at_the_Beach]

Application of technologies developed for computers in other areas.

[east1234]

I wonder how much energy is consumed in the cooling process?

[DManA]

I don’t get the advangage. Say you have a lense 20/20 cm. You concentrate the energy falling onto 400 sq cm into a smaller area. But then you throw away a lot of that energy with the “clever” cooling technology so, what’s the point?

[Ernest_at_the_Beach]

IBM researchers have achieved a breakthrough in photovoltaics technology that could significantly reduce the cost of harnessing the Sun's power for electricity.

[Captain Beyond]

bump

[ladtx]

...enough heat to melt stainless steel,...

IMPOSSIBLE!!!!!! Rosie told me that can't be done.

[PBRSTREETGANG]

[taxcontrol]

It is not a physics efficiency, it is a cost efficiency. By that, I mean that instead of either building one big PV cell to handle a 20x20 cm2 area, or by having to have 400 PV cells, you can now have a SINGLE cell. The most expensive part of converting light to electricity is the PV cell itself. IBM's trick is be able to concentrate so you don't need as many PV cells.

Yes some energy is lost in the cooling but that percent is much smaller than the cost efficiency gained by reducing the number of cells for the same area from 400 to 1.

[ClearCase_guy]

Sure, 1600 celsius, but if you stick on of these on it, it practically room temperature!

[DManA]

Why not just use a smaller lense so the temperature doesn’t rise to the point that you have to cool it?

[DManA]

Thanks. See my post #11.

[jonrick46]

The lens used to magnify the sun would have to be light weight. A Fresno method comes to mind. The collector would need to be cleaned periodically. A large application would put people to work cleaning solar collectors.

[antiRepublicrat]

Google paid nine figures for the development of solar cells that cost only $1 a watt, IBM paid for the most concentrated cells ever, T. Boone is taking the largest wind farm in the world online with 4 GW in three years.

And the left says government is necessary to advance the state of the art in renewable energy to save us from Global Warming. What has the government given us? Economic waste, plans that hurt more than they help. What has private industry given us? See above.

American ingenuity rules.

[taxcontrol]

Smaller lens means that you then collect less sunlight on the specific cell. Yes that is less heat, but now you have to have more cells for the same given area and thus reduce your cost efficiency.

[fso301]

I wonder how much energy is consumed in the cooling process?

If it's a heat pipe, zero energy is consumed and the transferred energy can be used to heat water. Heat pipes are extremely efficient at transferring heat and they do it passively.

[aruanan]

A Fresno method comes to mind.

Is that something they use in California? Or do you mean fresnel?

[ShadowAce]

[jonrick46]

LOL! (chocking on coffee). I wouldn’t touch California with a ten foot pole. I meant fresnel.

[JerseyHighlander]

Another company is developing mylar balloons to use as magnifiers over PV cells. Cheap, easy to handle, replaceable. But they would might melt if put over a 85C surface day in day out?

Youtube video of their demo project:
http://www.youtube.com/watch?v=kROgE4Jdm-k

homepage:
http://coolearthsolar.com/

[Prophet in the wilderness]

" to cool the solar cell from greater than 1600 degrees Celsius to just 85 degrees Celsius. "

Call me naive, but, that is impressive.

[rednesss]

They could use the heat to desalinate water and get 2 bangs for their buck.

[TheMightyQuinn]

" to cool the solar cell from greater than 1600 degrees Celsius to just 85 degrees Celsius. "

Call me naive, but, that is impressive.

I'm not impressed. I've seen a woman go from 1600 degrees to below freezing in a matter of seconds. Fortunately I lived to tell about it.

[cherry]

when my father died he had some IBM stock....not much...but I am proud to say that my 22yro and my 30 yro each have 6 whole shares apiece!

[Straight Vermonter]

IBM is also using its scrap wafers, from chip production, for solar cells.

http://www-03.ibm.com/press/us/en/pressrelease/22504.wss

[Sue Perkick]

Oh mercy

[ThomasThomas]

I have no issue with calling Fresno in honor Jim’s and freerepublic.com hometown.

[eraser2005]

I see your point with it being a cost efficiency issue.... However, I noticed that they’re claiming that it produces 70 watts from a concentrated 230 watts.

That’s 30.4% efficiency, a remarkably high efficiency for solar cells. Are these Gallium-Arsenide cells? Those are the only ones I’ve ever seen break 30%. But they’re danged expensive, so minimizing the amount used would be critical.

The other thing that I don’t remember a thing about that I wonder with this is what the effect of temperature on efficiency is on a typical array. The best of both worlds would be if concentrating the sun reduced the amount of cells you needed, and the cells used would increase in efficiency at a higher operating temperature.... You might need to cool them, still, but like a car engine, which runs best at a careful balance well above ambient temps....

[taxcontrol]

Yes, cells that can operate at high temps would be even a better solution. Unfortunately, almost all of that research, or at least as far as I know, has stopped. The focus of late is to create broad spectrum cells that can use more of the light by creating multi-layer cells, each that operate at a given light frequency.

[eraser2005]

Multi-layer is definitely worth pursuing as well, of course....

That’s been one of the biggest breakthroughs in recent years with digital cameras (see the X3 chip from Foveon, for an example)....