Solar Breakthoughs; +40% efficiency

[greenman3610]

This is the second one I've posted this week reaching
>40% efficiency. (This appears to be
a different discovery by a different team..)


http://www.eetimes.com/showArticle.jhtml?articleID=1966...




A breakthrough in solar cell technology promises to make solar power a cost-competitive energy option and to reduce U.S. dependence on oil.

With funding from the Department of Energy, Boeing-Spectrolab has managed to create a solar cell with 40.7% sunlight-to-energy conversion efficiency, said DoE assistant secretary for energy efficiency and renewable energy Alexander Karsner on Tuesday.

The solar cell represents "the highest efficiency level any photovoltaic device has ever achieved," according to David Lillington, president of Spectrolab. That claim has been verified by the DOE's National Renewable Energy Laboratory in Golden, Colo.

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On edit: here's the first one:

http://www.greencarcongress.com/2006/12/researchers_ach...

Michael Grätzel and his colleagues have developed a device that sets a new benchmark for efficiency in splitting water into hydrogen and oxygen using ordinary sunlight. The research will be published in the 13 December issue of the Journal of the American Chemical Society.

Previously, the best water photooxidation technology had an external quantum efficiency of about 37%. The new technology’s efficiency is 42%, which the researchers term “unprecedented.” The efficiency is due to an improved positive electrode and other innovations in the water-splitting device.

Most of today's solar cells are between 12% and 18% efficient. Some of the ones used to power satellites are around 28% efficient. In 1954, 4% efficiency was state of the art.

[aquart]

1. Coming thick and fast now.

The baby with the patent on the best of these better mousetraps is going to be a very contented baby.

[papau]

2. WOW - 40+% conversion makes heating oil in the northeast obsolete once

we get a way to store the energy and smooth out its use for heat.

[amandabeech]

3. Perhaps there would be a way to combine the H with the CO2 and CO

coming out of power plants to get something in the methane or propane range. We have the technology to store and ship both right now. In the northeast, which uses lots of heating oil, maybe it would be possible to really load up that hydrogen with carbon to produce heating oil so long as oil furnaces are around.

Hydrogen is hard to store--it makes metal brittle and requires lots of energy to cool and/or compress for storage, I believe.

If we could get methane or propane, we'd at least get much more bang for the carbon buck resulting from using coal.

[papau]

4. Excellent point - but getting a grant to study it from the Bush folks may be tough n/t

n/t

[amandabeech]

6. I have to beg off, since I'm no scientist.

Where's NNadir? He might know if something like that would be possible. Isn't he a chemist or chemical engineer by training.

I know he's somewhat of a solar skeptic.

There are actually many uses for hydrogen. One of them is in pulling sulfur out of many type of petroleum known as sour crude. Right now, the Feds have mandated no or low sulfur diesel that will spare our lungs. However, the hydrogen used to remove the sulfur comes from removing the carbon atom in methane (CH4). Although something like 2/3 of the hydrogen can be recycled, methane is not particularly abundant in North America and it is likely that we will feel the pinch sooner than with oil, according to some sources.

Does anyone know if the process requires distilled water or can it be used with untreated sea or river water?

[amandabeech]

7. Actually, the Green Car Congress article talks about making methanol

from CO2 and H2. Methanol could be made probably into DME, NNadir's favorite synthetic fossil fuel.

Using pure hydrogen in fuel cells would be great, but we'd have to make more equipment with more embedded energy and undoubtedly emitting more CO2. We have lots of new equipment that uses natural gas or propane that already has plenty of embedded energy and whose manufacture used lots of CO2. It may be more green-house friendly to replace those items with H2 using plants as the existing plants wear out, to the extent possible.

We must also work on H2 storage and transport facilities. H2 is difficult to store and transport.

[kestrel91316]

8. Unfortunately, NNadir is a skeptic about every alternative

except nuclear, from what I've seen. Not just skeptical, but snarkily, vehemently opposed.

Sad. Wastes all his time badmouthing viable alternatives, IMHO.

[bananas]

5. Can we get another recommend to put this on the greatest page?

There are a lot of people who wrote off solar PV in the past...
because it was only 5% efficient...
or 10% efficient...
or 15% efficient...
we are way past that now.
Thanks.