| Author | Message | ||
     Glitch |
http://www.technewsworld.com/story/Power-Plant-One -Small-Leaf-Could-Electrify-an-Entire-Home-72156.h tml Scientists at MIT have created what may be the first practical artificial leaf -- a device about the size of a playing card capable of splitting water into hydrogen and oxygen and storing the energy in a fuel cell. Placing the leaf it in a single gallon of water in sunlight could produce enough electricity to supply a house in developing countries with its daily electricity requirement, according to researchers. | ||
| Sifo |
Sounds interesting. I wonder how many years until they think it might be marketable. There's some pretty big promises in that article. Hopefully they can deliver. | ||
| Dennis_c |
we will never see it the power co. cant make any money off that.  | ||
| Sifo |
Why can't a power company make money off of a cheap way to make power? Of course it could be a very expensive way to make power, in which case you are correct. | ||
| Ezblast |
That's an awesome device - wow - cheap juice - who'd a thought - lol EZ | ||
| Hybridmomentspass |
Very cool idea, but like said, Im sure we'll not see it ever. And if we do it'll be many many many years from now. | ||
| Darth_villar |
"Very cool idea, but like said, Im sure we'll not see it ever. And if we do it'll be many many many years from now." Why do you say that? It seems the materials aren't highly exotic. | ||
| Glitch |
Very cool idea, but like said, Im sure we'll not see it ever. And if we do it'll be many many many years from now. Oh ye of little faith. | ||
| Blake |
"Placing the leaf it in a single gallon of water in sunlight could produce enough electricity to supply a house in developing countries with its daily electricity requirement, according to researchers." The report is confusing to me. The missing detail is how much electricity it takes to do that. Nowhere in the article do they talk about converting solar energy into anything. They only note how much electrical power is required to operate the thing, 1,000mA at 35mV per square cm or 350W/m2. Highly confusing reporting. Some of what is reported...
From what I gather, it sure sounds like you'd need a lot more than a single playing card sized array to power a home. Assuming it is 70% efficient and you want a hundred KW*Hrs per day of electrical power, you'd need around 100KWH/day/(4KWH/m2/day / 70%) = 35.7 m2. That's a 6m x 6m solar array. Unless I'm missing something, which may well be the case. But a playing card sized device to power a house? I don't think so. | ||
| 2008xb12scg |
Darnit Blake you made my head hurt again! me-But imagine if an artificial tree could power my house! utility-imagine what an artificial tree to power a house could sell for... | ||
| Sifo |
Blake you ignorant slut! You couldn't figure out how the volt got 230 MPG either.  The electrical input was pretty confusing. They were talking about powering a home in a "developing" country too. That might mean in the backwaters of China where they currently don't have electricity. Still, it would be nice if we did figure out a clean power source for our nation. If only we could split the atom...  | ||
| Glitch |
Ya gotta start somewhere. They're not trying to sell you anything, only telling you what MIT is working on. | ||
| Tiltcylinder |
I see a pond in every yard, with a rock shaped fuel cell nearby, generating power that can be stored without batteries. use the collected gas as required and the exhaust (water) trickles out of the rock back into the pond... might even provide enough gas for my eighty killowatt battery/fuel cell powered 2039 Buell XT. We can dream, can't we... | ||
| Aesquire |
"...generating power that can be stored without batteries..." What you'd be storing is hydrogen. ( no need to store the Oxygen, if you have air ) A plastic bag would do. For a few minutes. Then the hydrogen would leak out. It's a slippery little molecule. You can't keep hydrogen indefinitely in darn near anything. But, overnight is reasonable with, perhaps a Hdpe or aluminum tank & a small pump. Understand, they are talking about a solar cell with a electrically powered catalyst built as a single circuit board. Freaking brilliant! But you have to have a way to store the Hydrogen, and a fuel cell, ( not cheap ) or other kind of engine ( a converted gas powered generator ) to get electrical power out, later. It doesn't make electricity by itself, beyond what the built in solar cell ( not yet made in that form, that's the final, not yet available product ) produces to power the "leaf". Not quite ready for prime time, but a very promising development. A catalyst assisted cracking system for making water into H2 & O2 is the holy grail of energy research, right up there with Fusion. Of course, they will murder you for that. http://www.imdb.com/title/tt0115857/ | ||
| Rudy |
Nocera has done some interesting work. When I get a chance, I'll skim through his publication on the cubane catalyst. I read one of his older publications (Energy Environ. Sci. October 2010) and there were a couple of things that jumped out at me: the long-term stability testing was done in a solution with a specific electrolyte and made with ultra-pure water. It seemed a bit misleading that for this specific catalyst (not the one referenced in the news story in the OP's post) they were pitching that it could be used in the Charles river / saltwater, but when doing stability testing they limited it to perfect lab-conditions. They titrated it with calcium to see if that would cause it to foul, but honestly, I think it would've been a better idea to do stability testing in the river water / saltwater. Overall, neat work. Unfortunately, it's only half the piece of the puzzle. If the cubane catalyst is all they're hyping it up to be (I'll read the paper when I find time), that's great, but we still need a catalyst for the cathode (hydrogen evolution). In the paper I read (and also referenced in the news article) they used a platinum counter electrode. Not feasible for commercial implementation... $$$ Also, about the electrical measurements they referenced in the article, the catalyst isn't operating at 35 mV, that is the overpotential--the extra input needed to make the reaction actually happen (the lower the overpotential, the better). I think they're doing bulk electrolysis: applying a constant potential and observing the resultant current. Hence the 1000 mA/cm^2 at 35 mV overpotential. The larger problem (in my opinion) is a catalyst for the oxygen reduction reaction (reducing molecular oxygen to water in a direct 4 electron pathway). If they want to use the hydrogen they're creating during electrolysis of water in a fuel cell, they're going to need a catalyst for oxygen reduction--the state of art for this is currently platinum. Again, $$$. | ||
| Glitch |
You mean like the platinum in catalytic converters? |
