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Artificial Leaf Could Provide Cheap Energy
sciencehabit was one of several readers to tip news of a sunlight-harvesting artificial leaf, writing:
"Nearly all the energy we use on this planet starts out as sunlight that plants use to knit chemical bonds. Now, for the first time, researchers at the Massachusetts Institute of Technology have created a potentially cheap, practical artificial leaf that does much the same thing—providing a vast source of energy that's easy to tap. The new device is a silicon wafer about the shape and size of a playing card coated on either side with two different catalysts. The silicon absorbs sunlight and passes that energy to the catalysts to split water into molecules of hydrogen and oxygen. Hydrogen is a fuel that can be either burned or used in a fuel cell to create electricity, reforming water in either case. This means that in theory, anyone with access to water can use it to create a cheap, clean, and available source of fuel."
At last, true vaporware!
"Have you ever thought about just turning off the TV, sitting down with your politician, and hitting them?"
There's only so much insolation to harvest. If this is cheaper and higher efficiency than existing solar cells, then great. Based on the article, it's only 5.5% efficient, so meh. But even if it were 100% efficient, it's not some magical free energy machine, and never can be. While it's true that "nearly all the energy we use on this planet starts out as sunlight", a lot of that energy arrived at earth several millenia ago. In the long run, we're going to need to either use less energy (preferably by making things more efficient, not making do with fewer things) and/or get some near-unlimited fuel source, like fusion.
Ooo, 5.5%. And it's *potentially* cheap!
Get excited.
Read comments.
Excitement crushed.
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When applied to head it spontaneously regrows hair on bald men - best of all its reusable so earth friendly
. . . some of those pills from Charles Elton that turn water into gasoline. I was going to use it in my car with a Charles Nelson Pogue carburetor. Get a bazillion miles to the gallon. Put them A-rabs out of business. But the GOVERNMENT agents stole my stuff and deny everything!
Science fantsasy now becomes science fact.
Or did it?
"I believe in Karma. That means I can do bad things to people all day long and I assume they deserve it." : Dogbert
I saw a presentation on exactly this technology a few years ago at a conference, not from an MIT researcher. It's a strange phenomena, but within science MIT is just one of many research institutions doing great work, but to the public it has the most significant and frequent press releases. I mean, this isn't even a leaf, it's a silicon wafer which happens to be green and splitting water using catalysts is very old. The only innovation I'm seeing here is a new catalyst, which is pretty common in these fields. I also like the token quote from Bob Grubbs who won a Nobel prize in catalyst research and thus is interviewed in every catalyst article.
evil mech-treants which are a new form of cyborg life to dwarf our primitive digestive system.
According to Robin Williams, who as an alien should know what he is talking about, hydrogen as fuel for cars should be avoided. Remember the Hindenburg? Personally I don't car about the fuel, I just want my flying car.
Gary Dunn
Open Slate Project
Which is utterly pointless and just a factor to increase for more energy output. Wasted energy by not being able to absorb sunlight isn't a big deal: there's sunlight everywhere on average half of the day, barring clouds; wasted energy in gasoline is bad for example because there's limited amounts and/or it's expensive. The energy output/$ is much more important, as well as the ease and resource to make it.
Plus as some one who lives in Georgia I can tell you that is is hot! A solar shade for the state might work well!
According to a similar article in science daily http://www.sciencedaily.com/releases/2011/03/110327191042.htm it is 10x more efficient than (natural) photosynthesis.
I'm amazed that the foundation of life on earth is so inefficient (one tenth of 5.5% is only .55%!). Is this right? If it is then I'm glad our solar devices may not have to cover up too much of our planet to generate the energy we need (but if we ever develop solar powered self-replicating nano-bots, they will totally out-compete the natural biosphere).
Also, if this is true, then isn't this a major reason against using biofuels? I mean in addition to this inefficiency of photosynthesis, you've still got to convert it into some sort of fuel (but I guess the same is true of this artificial leaf; hydrogen is not the most practical of fuels). I guess maybe biofuels are still in the running because they can be "manufactured" very cheaply (farming and fermentation) with thousands of years of technology developed. (Or maybe it is the politics of the farming lobby).
(I'm also amazed that they used water from the Charles river in Boston and that it still worked. I remember a time when an accidental dunking in the none-too-clean river meant a quick trip to the doctor's office for shots!)
I know you are joking, but isn't hydrogen in hydrogen fuel cells stored as Lithium borohydride which isn't really explosive?
According to wikipedia, http://en.wikipedia.org/wiki/Electrolysis_of_water , traditional electrolysis is 50-80% efficient, and solar cells are ~20%.
http://en.wikipedia.org/wiki/Solar_cell_efficiency
Therefore, the efficiency of using the solar panel to power electrolysis would be .2*.5 -> .2*.8 = 10% -> 16%, wouldn't it?
So, unless there's a pretty substantial price benefit to the cell, where's the benefit?
Before we get too excited, apparently most of his research to date has been with cobalt, phosporus, tungstun and rhodium. Not sure where all this stuff comes from, but hopefully it is widespread enough won't turn into another middle east problem.
Also, at 5.5% efficiency, we would probably need quite a bit of this stuff which may cause some environmental issues by itself (mining, industrial polution, etc).
As a side note, many people talk about cutting back on petrol consumption as doing our part to reduce the demand for oil which comes from the problematic middle east, but I rarely hear of folks cutting back on electronics "toy" consumption to reduce the demand for coltan (the ore where much of the tantalum for capacitors comes from) which is causing huge problems for countries like the republic of congo. Haven't heard much about the coltan topic on /. Just be cause it's "electronic" and doesn't use oil doesn't mean it's better when scaled to industrial quantitites.
Not saying this proposed "artificial leaf" technology could definitly cause this kind of natural resource scarcity/extraction problem, but the sad fact is that if this becomes industrialized, it may not be much better than what we have today and most folks aren't even aware of the problems we have today (or even care).
normal solar is at about 25% or something.... I'm not sure what conversion rates to hydrogen (or something portable and storeable) are, batteries are generally crap,
Current best processes have an efficiency of 50% to 80%,
So assume 'real cheap' where talking maybe 10% efficiency using normal solar... so it only has to be 'half' the price and it's cost effective... and I'd assume the efficiency will go up.
thank God the internet isn't a human right.
I know how to power my new 2011 ford steam engine! With a plastic fire. Now off to eBay for some bushels of Fake Plastic Trees
This was on NOVA two months ago! http://www.pbs.org/wgbh/nova/tech/making-stuff-cleaner.html
When you start talking about that scale, even solar is no longer free. All that sun, hitting the land or the sea, you don't think that energy is otherwise "wasted" or destroyed? It goes to heat the earth. If you capture it with solar panels or other methods, that energy never gets where it was going.
I don't have any good idea what the impact of that is, but you can't just discount it as "free".
I work for the Department of Redundancy Department.
For solar power to work and be economically viable, it needs to be in orbit. Period. No solar cell, no matter how efficient is going to be viable under an atmosphere. We should have a new space race to build a space elevator... once its complete we can have all the orbital arrays we want for cheap. Near limitless power.
you think leaves grow on trees!?
interesting, come back and tell me when i can get an electricity tree at Home Depot or Lowes'
Politics is Treachery, Religion is Brainwashing
From the article and the details they're giving, it doesn't sound very good way to produce fuel. First the sunlight has very low efficiency. And if you're splitting water, you won't get any more energy out than what you could utilize from the sun's energy. And everyone who has spent any time outside during summer knows that the amount of energy that hits the earth can warm it slightly, but it hardly has enough energy to move your car. This means that we'd need to cover very large amount of earth's surface with these panels until you can drive significant number of cars with this fuel.
The reason why oil can move your car is because it took a million years for plants to store energy which was then converted to oil. It's not very good if you need to wait million years before you can drive half a mile with your car. With this tech that splits water, you'd actually keep the panels working for thousands of years before you can get enough fuel....
Once we run out of oil, we will have big problems. Hopefully by that time, they can get cold fusion to work reliably and make it run our cars.
"This means that in theory, anyone with access to water can use it to create a cheap, clean, and available source of fuel.""
access to water and a hydrogen rated compressor.
See cool science article. Get excited. dress
According to Robin Williams, who as an alien should know what he is talking about, hydrogen as fuel for cars should be avoided. Remember the Hindenburg? Personally I don't car about the fuel, I just want my flying car.
While hydrogen is flammable, there are doubts about it being the true cause of the disaster. Based on eyewitness accounts, the fire was bright red while hydrogen burns blue. There are competing theories like the paint composing of aluminum.
Well, there's spam egg sausage and spam, that's not got much spam in it.
There is not an energy production problem there is an energy storage problem. Almost all green sources of energy have have down times. In the case of solar energy that is night. If we could store some of the energy produced in the day we would be much further ahead. There is some research and a few test being done but energy storage is not as "sexy" as energy production.
Even though the efficiency is only 5.5%, while solar cells are several times more efficient, these silicon wafers are actually better. It sounds like they're cheap since they don't use platinum or gallium (and using cheap materials was the goal) BUT no PEM electrolyzer stack is required!! All you need is the wafer and sunlight to make H2 and O2!!! (It's like the solar cells AND the electrolyzer all in one). This is awesome! I wish I had like many square meters of this stuff so I can throw it in a pool and water the hydrogen and oxygen bubble from them!! How cool! Unlimited fuel! I wonder how fast you can collect like one cubic foot of H2 from a playing-card sized wafer in direct sunlight.... I guess I can calculate that based on the efficiency....naw... I need a beer.
It seems to me like this would be a good candidate for grid storage. Say you had a solar farm with both conventional solar cells and this new technology. When the sun shines, the regular solar cells both provide the product energy from the power plant, and also operate pumps that pressurize the hydrogen and oxygen coming off of the new cells. At night and when clouds come overhead, the system switches to fuel cells to burn the stored hydrogen and oxgen, regenerating the water in the process, and keeping the power plant producing electricity through the night. Thus, you overcome the biggest problem with solar power plants -- their intermittancy. Such a power plant, properly designed, should be able to produce continual power effectively indefinitely, barring extremely long periods of overcast weather. The "nighttime" capacity of the power plant would be a function of the size of the hydrogen tanks you could store on site -- and I believe that pressurized gas tanks scale upwards very cheaply and easily. As a bonus, the water in the system would be continually contained and recycled, making the system attractive for use in arid places like deserts where solar is most profitable.
Hopefully it will turn out to be cheap in practice and can be used this way.
Gee, someone solved the energy problem. Why am I still skeptical?
most of his research to date has been with cobalt, phosporus, tungstun and rhodium. Not sure where all this stuff comes from, but hopefully it is widespread enough won't turn into another middle east problem.
Production locations for:
Cobalt
Phosphorus
Tungsten
Rhodium
Not looking good...
While hydrogen is flammable, there are doubts about it being the true cause of the disaster. Based on eyewitness accounts, the fire was bright red while hydrogen burns blue. There are competing theories like the paint composing of aluminum.
Alright then, I guess it's ok to fly through the air in blimps filled with hydrogen. Sure.
"First they came for the slanderers and i said nothing."
Instead of storing a dangerous, readily combustible mixture of H2 and O2 from this process, is it easy to isolate the 2 gases and store them separately?
Hydrogen is the most efficient rocket fuel be quite a margin. But even in rockets where performance is that important it's not universally used. Why?
For one it's a bitch to handle. Leaks through tiny holes, goes into/through metals, forms explosive gas. It's difficult to store, and it's low density even in liquid form (70kg/m^3). So you have to build huge, massive tanks.
If even in rocketry terms it's difficult to handle, what makes those hydrogen proponents think it will be manageable in a large scale?
Photosynthesis in sugar cane is 7%-8% efficient and compared to this is practically free (needs water and land, but so does this). The stuff manufactures itself for crying out loud, we don't even have to invent nanomachines to construct it for us.
The whole point of photovoltaic panels is that they convert the sunlight directly into electricity for our applications which need electricity. If instead you're going to convert the sunlight into a hydrogen-based fuel like this device, just plant some vegetation and convert its cellulose into alcohol-based biofuel and burn that instead. It's a helluva lot cheaper. The fuel is liquid at room temperature and 1 atmosphere, so is a helluva lot easier to store, transport, and handle than pure hydrogen. And even though burning alcohol fuels releases carbon, it's still carbon neutral since making it consumes the exact same amount of carbon from CO2.
Unless you're in a weight-sensitive application like the space program, or they can get this thing's efficiency up to about 20%-40%, I don't see what the big deal is. Biofuels are much more practical than hydrogen for most applications.
Once we harness the power of gravity all other sources of power will become obsolete.
That's why people buy the idea that the coating was what actually exploded.
Computers are useless. They can only give you answers.
-- Pablo Picasso
For solar power to work and be economically viable, it needs to be in orbit.
And your evidence for this is what exactly?
No solar cell, no matter how efficient is going to be viable under an atmosphere
Really? You do realize that almost all life on this planet derives its energy from photosynthesis which is simply an organic solar cell. Your argument seems to have a fatal flaw unless you get a lot more specific.
We should have a new space race to build a space elevator
So we should ignore development of solar cells which we know work (even if they aren't the most economic choice at present) in favor of the extremely unlikely chance we could develop a space elevator. An enormously complex device we aren't even sure is possible and which requires materials that are hugely stronger than anything we know how to build. Why not just go for broke and build a dyson sphere while you are at it? I like science fiction as much as anyone here but a space elevator is only slightly more likely to happen than FTL space travel.
once its complete we can have all the orbital arrays we want for cheap.
Cute how you think building this fictional space elevator will be cheap.
See, here's the thing. You may very well be right. But I am not about to test that theory with my life by stepping onto a hydrogen filled blimp, thankyou.
"First they came for the slanderers and i said nothing."
The op asserting that hydrogen caused the Hidenburg disaster; it's not clear that it was. Also if the hydrolysis of the artificial leafs works out, it is possible to use fuels cells in practical applications. The main problem of fuel cells is getting and storing hydrogen fuel to power the cells. As for handling hydrogen, it probably is no more dangerous than handling natural gas. There is a difference between using hydrogen as the fuel and hydrogen as buoyancy gas.
Well, there's spam egg sausage and spam, that's not got much spam in it.
Ooo, 5.5%. And it's *potentially* cheap!
The data you are sourcing and the point you are making are not relevant to each other.
Lifespan of product and production costs are something you would want to be talking about.
I see a lot of articles that start with "researchers at _blank_ have created/invented/etc.." at which point it is forgotten and I hear of it again. case and point, awhile back I saw something about spray on infrared solar panels and then there was that nano bug that could fix concrete..
Hydrogen does not burn blue, it can not make any light whatsoever. Watch the Space Shuttle, no light from it's exhaust except the the glowing ceramic nozzle. However, you are still probably correct on the dirigible.
production costs are something you would want to be talking about.
Okay. They say it's potentially cheap. Potentially. As in it's currently not cheap. In fact it's probably freakin expensive. And as someone else pointed out, nature does a better job of producing and storing hydrocarbons.
"This means that in theory, anyone with access to water can use it to create a cheap, clean, and available source of fuel." Of course it's just in theory because the process will be sold to a corporation and the energy produced will be sold to everyone else at an elevate price.
Mechanical tree, mechanical tree,
What thee be, mechanical tree.
With limbs of steel and roots of power,
You form a great mechanical tower.
Tree
Everything you can mass-produce in a factory > stuff that needs vast fields to grow. After all, didn't we learn anything from the corn debacle when people thought it a good idea to convert to biofuels?
But I do agree that hydrogen is not the messiah of all our energy needs. Being able to convert it directly, though, is a neat trick none-the-less... only: If current solar cells have thrice the efficiency, we could attach a few of them to an electrolysis apparatus right now and have a similar effect.
Still... if they can push the efficiency some (and I think that's highly probable), this will be a pretty cool thing. Not world changing but pretty cool.
Yes, but you then have to convert the sugar cane to something else (ethanol for example). So you have to look at how much energy you get out of the ethanol you get after you convert the sugar cane which you created with 7-8% efficiency.
I suspect that if you are converting directly to a usable energy source at around 5% it would be fairly competitive and may require less steps (capture hydrogen, compress and store, versus grow sugar, harvest, then truck somewhere to a chemical plant to covert to alcohol etc etc.)
Overall energy efficiency for your proposed scheme? Remember, you lose some in each conversion. How about the logistics? How much land? Can it be used year-round? Can it be sited in a desert? Are you sure land and sunlight are the only needed inputs? What about fertilizers, pest control, land management? Speaking of which, is your scheme carbon-neutral after you factor in the farming machinery used?
Does this tech need pure distilled H2O or will salty sea water work? You see, we haven't got that much fresh water going around...
One of the numerous problems with hydrogen is that you need very high pressures to store any decent amount of it in a container. And anything at very high pressure has the protential to be extremely dangerous. So more dangerous in handling stored than natural gas. As a transfer medium or as buoyancy though, I agree.
OG.
One of the proposed uses for an old Ford plant is a large parking area that will offer protected parking under solar panels, on the order of 30 acres
http://www.ajc.com/business/solar-paneled-parking-on-883353.html
* Winners compare their achievements to their goals, losers compare theirs to that of others.
You need to add some Oxygen.
And to explode, you need the right ratio H2/02.
The fire should then have occure at the interface between the blimp filled with H2 and the air filled with 20% O2.
It happens that's also where the shell of the blimp was.
Perhaps this seems a bit trollish, but help me to understand.
I have seen this article posted a few places and every place seems to have an alarmingly high percentage of people who basically say, * Rable rable rable, tree huggers bad, global warming fake, rable rable rable".
My question is why? What is going on the states that make so many people believe that there is no need to mediate or even think about possible damage to the environment which supports us?
Is global warming for sure real? Fuck if know, but it sure seems possible. And that's a fuck-all big gamble you all are taking.
...in the wilderness for toiletries, the results could be shocking.
long long time ago
Hydrogen does not burn blue, it can not make any light whatsoever.
"Can not" is a strong statement to make in science. There are 4 lines in the Balmer Series in the visible part of the EM spectrum for hydrogen.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
The whole point of photovoltaic panels is that they convert the sunlight directly into electricity for our applications which need electricity.
Right, but sometimes we need electricity when the sun isn't shining, like, say, at night. So how do you store that electricity?
If instead you're going to convert the sunlight into a hydrogen-based fuel like this device, just plant some vegetation and convert its cellulose into alcohol-based biofuel and burn that instead.
And how efficient is the "vegitaion -> Alcohol" process? If its not 68.75% efficient, the 5.5% efficiency wins. And considering the beasties that do the cellulose to alcohol conversion require energy, then the heat required to boil the alcohol out in the distilling prossess, I don't see it making that bar by a long shot (I'd be surprised if we are hitting 15%).
The issue with almost all "Green" power technologies, except nuclear and in some cases hydro-electric (maybe geothermal too?) is power is generation occurs when it occurs, wheras demand spikes and ebbs throughout the day. Even convential fossil fuel has trouble with this (Big power draw spike at 7am every morning as coffee makers around the area turn on, made worse by modern timers ensuring it happens almost simultaneously), so power companies need special surge handling systems that can react faster than tradditional plants. So the big problem will boil down to energy storage; conventional batteries versus hydrogen or carbon based fuels (or molten sodium, or giant capacitors, or whatever). And in some cases mybe what you want IS hydrogen (for your blimp, sattelite, submarine, etc), going direct to hydrogen is nice since eliminating the H2O -> H2 + O2 saves a lot of inefficient steps,,,,
Of course, alcohol is much simpler to store
:\ http://dilbert.com/strips/comic/2011-03-29/
San Francisco Photographers
....many times. If you read the original NREL attempts, the key to remember is that the catalysts use any electron donors, including a simple energized grid, to accomplish the electrolysis. The only interesting twist here is that the researchers have eliminated the energized grid and replaced it with a doped silicon wafer. The conversion efficiency is *exactly* what you would expect from such an approach. In short, the approach is to use something closely resembling a conventional solar cell, deposit catalyst material in intimate contact on either side, and voila...you have a solar cell providing donor electrons at ~20% efficiency to a catalyst operating at ~30% efficiency, yielding around 5% efficiency overall.
This is a neat trick, using apparently more stable catalysts than before, but hardly a breakthrough when a person can use the same catalysts and an energized grid to yield ~90%+ efficiency in electrons and the same 30% efficiency for the electrolysis part, yielding 27% overall efficiency. For that matter, direct electrolysis can yield 50%-80% efficiencies from an energy source.
This is part of a larger shell game, as are most "breakthroughs". Read the papers. Read the history of the principals. The rest is hype.
Based on the article, it's only 5.5% efficient, so meh.
So do something to help solar energy capture R&D...
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1. Efficiency.
At 5.5% efficient, it's not competing with solar cells yet -- but this is a prototype. We can expect better efficiency with time.
2. Rare elements.
the use of tungsten and rhodium could be a deal breaker for mass implementation. There too, however, once the solid state physics guys mix in, there may be better options.
3. Shading
The people in Georgia may not want their entire state covered. There's a fair amount of the country that shading 30 to 50 percent would make the land MORE productive.
4. Albedo
This is a big concern to me. If these solar leaves average darker than the surrounding landscape then mass implementation of them reduces the amount of sunlight reflected into space. This is one positive feedback loop in the arctic. -- Conifers are close to black from above. Tundra reflects 30-50% of light in summer and 85% in winter. As the earth warms, treeline moves north, increasing the amount of heat collected. (It also increases the snow free time of the year, increasing the heat collected.) We're already seeing significant change in the arctic.
5. Hydrogen economy. Seems to me that such a leaf is going to require a rats nest of small plumbing to collect the hydrogen. H2 is tricky to pipe around at the best of times. Collecting it in quantity will be tricky.
This isn't a show stopper. The methanol economy makes a lot more sense. Methanol has better energy density/volume at reasonable pressure, and liquids are easier to store and move around. The conversion of H2 to methanol should be possible with reasonable efficiency with the right catalysts.
Third Career: Tree Farmer Second Career: Computer Geek First Career: Teacher, Outdoor Instructor, Photographer.
Just be aware that if this tech has the ability to "replace" fossil fuels such as oil and coal, the patent will be bought up and suppressed until those fossil fuels no longer exist--or until such time as it can be commercially developed. 5.5% efficiency is a good startup, but need s to be developed to a greater rate of conversion. This means that it will require large quantities of money. Like cures for cancer, this one will not be developed in the lifetime of anyone reading this. There is just too much investment in current fossil-fuel tech for the companies and countries involved to allow this tech to be developed, marketed and put to use.