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

wired.co.uk

11–20 of 66 posts

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

#11
I'm guessing the substance he is using is Melanin. I've already heard of something like this. Mexican scientist, Dr. Arturo Solis Herrera, when studying the properties of melanin, discovered that this substance is to the human body, what chlorophyll is to plants. He achieved alternative energy generation using self-renewing photoelectrochemical cells which separate water into hydrogen and oxygen and then bring the atoms together again. Check it out!!! http://www.energiaadebate.com/Articulos/noviembre2007/imagen...

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

#12
post #7

How are these reconciled? Optimism?: Re: previous artificial leaf: It was also highly unstable, and had a lifespan of barely one day. and Nocera's leaf is stable -- operating continuously for at least 45 hours without a drop in activity in preliminary tests

The previous artificial leaf and the current one are different things.

But 45 hours and one day aren't that different.

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

#13
post #12

Earlier quoted context omitted.

The previous artificial leaf and the current one are different things.

But 45 hours and one day aren't that different.

Well, different but I agree, not different enough to call one highly unstable and the other stable.

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

#14
post #12

Earlier quoted context omitted.

The previous artificial leaf and the current one are different things.

But 45 hours and one day aren't that different.

Being at ~100% after 45 hours and at 0% after 24 hours are quite different.

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

#15
post #2

If this is as good as it seems to be, why is the focus purely on the third world? Unless I'm missing something, this could bring cheap and extremely environmentally friendly energy to developed countries too. If it's purely a case of "they need this more than we do", why not either just license out the technology to companies who can use it, or develop it themselves for developed countries. Either way, they could tak…

I would wager it's also an issue of corporate politics. If these leaves are capable of creating a sustainable in-house power generator, you will have no more need to buy electricity from your local provider. (Or at least in significantly reduced quantities). This obviously won't sit well with them.

Consider then that it's these companies which have the expertise to develop and commercialize a technique like this. You need to keep them on your friendly side when you are about to market. Going for those locations which are not paying customers anyway, is a safe move from an economic p.o.v. At least until said corporation can figure out a way to monetize the new product in a way that does not reduce their profit.

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

#16
post #5
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.

I think the point is that it can use that small amount of energy to break the hydrogen bond in the water, releasing more energy than was used. Edit: Apparently I made a mistake. See the correction, which I was the first to upvote.

Pisses me off that comments like the one I'm replying to get downvoted. He expressed his understanding of the science, if he's wrong then by all means explain why and upvote those who have explained why - but don't downvote just because somebody made a mistake, it's surely better to have the discussion than for nobody to bring it up.

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

#17
post #9
post #2

If this is as good as it seems to be, why is the focus purely on the third world? Unless I'm missing something, this could bring cheap and extremely environmentally friendly energy to developed countries too. If it's purely a case of "they need this more than we do", why not either just license out the technology to companies who can use it, or develop it themselves for developed countries. Either way, they could tak…

"With a single gallon of water, Nocera says, the chip could produce enough electricity to power a house in a developing country for an entire day." I think a house in a developing country is key. They say the chip is 10x more efficient than a natural leaf. I don't think 10 leaves produce a whole lot of power... I'm curious how it compares to a traditional photovoltaic solar cell.

In fact, the framing of the performance characteristics of this this artificial leads me to believe that the selling point is their ease of manufacture. That is, they are less efficient than traditional solar cells, but cheaper/easier to make.

Just a guess, though. Would love to see actual figures.

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

#18

I'm guessing the substance he is using is Melanin. I've already heard of something like this. Mexican scientist, Dr. Arturo Solis Herrera, when studying the properties of melanin, discovered that this substance is to the human body, what chlorophyll is to plants. He achieved alternative energy generation using self-renewing photoelectrochemical cells which separate water into hydrogen and oxygen and then bring the at…

No, it's not Melanin. It's a cobalt oxide complex.

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

#19
post #14
post #12

Earlier quoted context omitted.

But 45 hours and one day aren't that different.

Being at ~100% after 45 hours and at 0% after 24 hours are quite different.

Since you're intent on belaboring the point, it doesn't claim that one is at ~100% and the other was at 0%. More significantly, if the assertion is that one is more stable, don't you think it would be more compelling to demonstrate its operation for, say, a month? Or did they build this one leaf 45 hours before issuing a press release?

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

#20
post #6
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.

Does no one follow energy news, except for oil prices and the Polywell project?! :-)

Many estimates talk about soon reaching "grid parity" in large parts of the world. If this leaf isn't good enough, there will be some other solar variant soon.

http://en.wikipedia.org/wiki/Grid_parity

It seems to go faster than this prediction from 2009: http://news.bbc.co.uk/2/hi/8386460.stm

(Kurzweil argued in 2008 that solar energy will take over http://www.livescience.com/4824-solar-power-rule-20-years-fu... )

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