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MIT's artificial leaf is ten times more efficient than the real thing (Wired UK)

wired.co.uk

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Re: MIT's artificial leaf is ten times more efficient than the real thing (Wired UK)

#61

Post by GFischer »

DannoHung wrote: post #53
ars wrote: post #48

Earlier quoted context omitted.

BTW one reason that Grid Parity is a moving target is that one of the input costs to making solar power is energy. When energy (hydrocarbon fuel) becomes more expensive, instead of making solar power cheaper in comparison, it has no real effect. Instead, regular power becomes more expensive, which makes building solar power also more expensive, and the net result is a wash.

That seems weird. That would imply that the lifetime energy capture of a solar panel is roughly equivalent to the creation and installation energy cost.

Indeed. That used to be said of eolic energy (wind power). For example you can see a cost breakdown in 2005 here:

http://www.mnforsustain.org/windpower_schleede_costs_of_elec...

I believe the energy costs are now competitive (but wind still cannot serve as "base" power), but my yet-unresearched hunch is that solar is still at the same stage that wind was: only viable due to the massive tax breaks.

Re: MIT's artificial leaf is ten times more efficient than the real thing (Wired UK)

#62

Post by randallsquared »

DannoHung wrote: post #53
ars wrote: post #48

Earlier quoted context omitted.

BTW one reason that Grid Parity is a moving target is that one of the input costs to making solar power is energy. When energy (hydrocarbon fuel) becomes more expensive, instead of making solar power cheaper in comparison, it has no real effect. Instead, regular power becomes more expensive, which makes building solar power also more expensive, and the net result is a wash.

That seems weird. That would imply that the lifetime energy capture of a solar panel is roughly equivalent to the creation and installation energy cost.

Doesn't seem weird at all, I think. Solar just barely passed breakeven in the last decade, unless you factor in subsidies. I notice that for a random zip code in Maine, http://bpsolar.cleanpowerestimator.com/bpsolar.htm shows that absent federal and state subsidies, you'll save only about $4600 over 25 years with their default settings. It's phrased as saving $36K, though, due to subsidies and interesting presentation. :) But BP Solar really wants you to buy solar panels, of course.

Re: MIT's artificial leaf is ten times more efficient than the real thing (Wired UK)

#63

Post by grammaton »

"Nocera's leaf is stable -- operating continuously for at least 45 hours without a drop in activity in preliminary tests -- and made of widely available, inexpensive materials -- like silicon, electronics and chemical catalysts."

So semiconductor grade Silicon is readily available and easily manufactured in a third world country? Or will they have to buy the finished product from first world countries? If they do, where do they get the money? Unless they can build it themselves - and it doesn't sound like they can - how will it help them?

Re: MIT's artificial leaf is ten times more efficient than the real thing (Wired UK)

#64

Post by tesseract »

mryall wrote: post #58
tesseract wrote: post #21

Earlier quoted context omitted.

I don't see, in the linked article, a comparison of the efficiency of this device to that of existing solar panels (which are quite a bit more efficient than natural leaves).

> [solar panels] are quite a bit more efficient than natural leaves ... Got a citation for that? I'd be interested to learn more.

http://en.wikipedia.org/wiki/Photosynthetic_efficiency vs 10% to 30%+ for solar cells (depending on technology/price).

Re: MIT's artificial leaf is ten times more efficient than the real thing (Wired UK)

#65

Post by anamax »

corin_ wrote: post #6
jbri wrote: post #4

Earlier quoted context omitted.

Earth receives about 1.3 to 1.4 kW per square meter from the sun (and that's before the atmosphere absorbs and reflects a huge chunk of that) - which is effectively an upper bound on the energy that can be produced by any solar power source. A playing-card sized device is going to take more than a day to produce a day's worth of electricity for a current developed-world lifestyle, even if it were 100% efficient.

Solar panels are already good enough that they are used in developed countries such as USA and UK. Are they perfect? No, they cost too much, and they don't generate enough electricity, but they are used none-the-less. By the sound of it, this new creation would be more efficient, either in price, electricity generation, or both, than traditional solar panels - if that wasn't the case, why on earth would any project u…

> Solar panels are already good enough that they are used in developed countries such as USA and UK. Are they perfect? No, they cost too much, and they don't generate enough electricity, but they are used none-the-less.

Subsidy and vanity explain a lot of economic activity.

Plus, energy costs are not very uniform. It's much easier/cheaper to get power to the next house in a suburb than it is to get power to a freeway sign 10 miles from the nearest town. That's why solar is cost effective in some situations even when it doesn't make sense in general.

Re: MIT's artificial leaf is ten times more efficient than the real thing (Wired UK)

#66

Post by serichsen »

dctoedt wrote: post #56

Is "photosynthesis"[1] the correct term? Seems to me that "photolysis"[2] would be closer (although readers would get the gist of the former more quickly). [1] http://en.wikipedia.org/wiki/Photosynthesis [2] http://en.wikipedia.org/wiki/Photodissociation

I agree. Photosynthesis would be to split carbon dioxide, release oxygen, and use the carbon to sythesize some organic compound.
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