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Using Sun's Energy to Split Water Means Solar Power All Night
Posted by
timothy
on Thu Jul 31, 2008 06:05 PM
from the party-like-it's-2099 dept.
from the party-like-it's-2099 dept.
phorm writes "Reuters is carrying an article about a recent MIT development which may pave the way for solar-energy to be collected for use in low-input periods. According to Reuters, the discovery of the a new catalyst for separating hydrogen+oxygen from water requires only 10% of the electricity of current methods. This would allow storage-cells to function as a form of battery for other forms of energy-collection, such as solar panels. The new method is also much safer (and likely environmentally friendly) than current methods, which require the use of a dangerously caustic environment, and specialized storage containers." sanjosanjo points out coverage of the process at EE Times, which features the MIT group's press release.
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I have my doubts... but, (Score:5, Insightful)
If that is true (although I definitely have my doubts, as tales and empty promises of the past have made all of us highly skeptical when we read something like this), then it should open the road for a significantly more efficient means of producing hydrogen for hydrogen powered cars / devices. Hell a car equipped with a solar cell could just bake during the day to recharge itself and be ready to go for the commute home come 5pm. Though until I hear a confirmation of MIT's findings from another university/respected source, I hold on to my severe doubts about this.
Re:I have my doubts... but, (Score:5, Insightful)
"Though until I hear a confirmation of MIT's findings from another university/respected source, I hold on to my severe doubts about this.
MIT isn't really in the habit of making unsubstantiated claims of new discoveries. That's pretty much the purview of startup companies in need of funding and no-name universities looking for grants. MIT et al stake their reputations on their discoveries, and do not generally cry wolf.
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Re:I have my doubts... but, (Score:5, Insightful)
Extraordinary claims demand extraordinary proof. In any case, you don't let any researcher (or institution) off the hook because of his popularity - what kind of science would that be?
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Re:I have my doubts... but, (Score:4, Funny)
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Re:I have my doubts... but, (Score:4, Interesting)
I tend not to believe MIT because of their "popularity" so much as because of their "reputation."
The latter could be rather heavily damaged by making unsupportable claims in regards to their research.
Not that we shouldn't wait to see this in action, but at the very least I'll be waiting eagerly to see these experiments repeated in a controlled environment.
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Wrong (Score:5, Insightful)
> Extraordinary claims demand extraordinary proof.
No, extraordinary claims require ordinary proof that has been vetted extraordinarily well.
Otherwise, someone can arbitrarily declare claims 'extraordinary' and simply raise the bar every time the proof meets their old standard. You know, like they do with global warming, or evolution.
Sorry, but that soundbyte just gets to me.
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Re:I have my doubts... but, (Score:5, Informative)
But these claims really aren't as extraordinary as you might think. They've found a new catalyst that reduces the amount of energy required to split water. That's what catalysts do--they reduce the activation energy of a reaction. Life would not function without catalysts. Every enzyme in your body (there are thousands of them) is a catalyst designed to make some reaction run efficiently at body temperature.
Every few years a breakthrough catalyst is discovered that makes new reactions feasible. See for example the Grubbs' catalyst [wikipedia.org] which when discovered had almost magical properties compared to the state of the art. Grubbs recently won a Nobel prize for this work.
Currently, platinum is a catalyst on the cathode, for generating hydrogen. This works well and has been known for a long time. This new research has found a useful catalyst for the anode, which generates the oxygen.
While this might be a major breakthrough, I don't find it to be extraordinary, at least in the same sense that a self-sustained cold fusion reaction is extraordinary. These results should be easy to duplicate in other labs as the materials are straightforward.
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You still have to be careful (Score:5, Informative)
For one, professors have to get grants to do their research, so they are sometimes given to overstatement to that end. They are, after all, only human which means that not all of them are honest. Also, some are simply unrealistic. They think they can do something, so they announce it, even though they have no idea how to get there, and then maybe never end up doing so. Finally sometimes shit just ends up being impossible. It looks good, seems like things will work, however in the end you can't make it happen. That happens with research. You can spend millions only to realise you've been down a dead end and there's nothing to be done about it.
I agree an announcement from a major university is much more credible than some startup, but don't think things out of universities aren't overstated at times.
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Re:You still have to be careful (Score:4, Insightful)
See, for example, the claims on cold fusion some years back.
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Re:I have my doubts... but, (Score:5, Informative)
Indeed, Nocera has been working on this for what must be at least 15 years by now. I remember he had some catalysts four or five years ago that worked using only the ambient intensity of sunlight, but were far too expensive to be practical (so I heard).
I also work in catalysis, and one of my friends is doing water splitting, so I've read a few papers on the topic. The materials used don't surprise me, cobalt is approximately as good as you can find. Also, I would note that this catalyst (I downloaded the paper) is releasing oxygen and gradually producing HPO4, which can then later be oxidized to (presumably) release energy. I'm not familiar with using phosphoric acid as a fuel, but the paper sounds extremely plausible.
I would also suggest that, based on my reading of the paper, any real world applications would be 5-15 years away, depending on how well they're able to coat their electrodes.
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Re:Vaporware (Score:5, Funny)
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Re:I have my doubts... but, (Score:5, Informative)
Lets say your house needs 5000 W. To get through an 8 h dark period, you need 40 kWhr, or 136,000 BTU. That's roughly the energy in 2 lbs of hydrogen. To store that much hydrogen, you either need a balloon of 11 m^3 size, or you need a compressor that allows you to store the hydrogen as compressed gas (what costs energy to do) or to liquefy the hydrogen (what costs even more energy). Alternatively you can adsorb the hydrogen into certain alloys, but then you need to heat them to get the hydrogen back out, again ruining your energy balance, and driving up the cost.
This development can help with the development of a large scale hydrogen infrastructure, but there we're better of with natural gas (of which we're not running out anytime soon, and which has much less technological hurdles in storage).
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Re:I have my doubts... but, (Score:4, Funny)
Why not just leave it stored as water, then, and electrolyze it as needed?
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Re:I have my doubts... but, (Score:5, Interesting)
Lets say your house needs 5000 W.
Let's not. That's more power draw than the total available service into most houses; and most houses don't exactly draw at max for 8 hours straight. Divide your numbers by 5, and you have a more reasonable estimate.
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Re:I have my doubts... but, (Score:4, Funny)
Where do you live? Afghanistan? I live in a Central American country with crappy electricity and this house is often drawing way more than 5000 W. There are eight computers running, two refrigerators, a large freezer, four air conditioners, a heater in the pool, an electric stove, washer, dryer, and much more.
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Re:I have my doubts... but, (Score:5, Funny)
And they say Americans are energy hogs?
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Re:I have my doubts... but, (Score:5, Informative)
15 amps? 120 watts?
No, most houses have 100-200 amp service. At 120 volts. Which works out to 12000-24000 watts, peak. Average electricity consumption is right around 1 kilowatt, so the poster who said to divide by 5 was right.
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Re:I have my doubts... but, (Score:4, Insightful)
Huh???
I don't know what kind of cave you guys live in, but (not meaning to be politically incorrect here) I have AC in my house. 1 kilowatt is only ten 100 watt light-bulbs. Yeah, yeah, I've switched out to low energy fluorescents, but there are still more than 30 light bulbs in my house, and since there are seven people living here (three kids, two parents and two grandparents) you can bet that most of those bulbs are on simultaneously at one time or another. Plus the A/C. plus we like to actually cook our food before we eat it...
Bottom line, we use about 200 KWh per DAY. In other words, 10 KW times 20 hours. And I've got the utility bills to prove it.
It's easy to be critical when you're a college kid living poor, but get a bunch of kids, try supporting your parents too, and get a little bit of affluence under your belt, and you start to see things differently.
No, I'm not one of the "burn it all!" blue-sky republicans. Nor am I a 'let's go back to the golden days of agrarian societies" types. Jeeze, do your homework and see what that low-energy society was REALLY like!
No, Civilization needs one thing for sure. MORE ENERGY! But clean, and cheap, and abundant. We need solar, nuclear and anything else that will fit the bill, but conservation as an energy strategy is a mistake. It helps, but it will not solve the problem.
Look up the Kardashev scale, and think about how energy consumption has changed in the last 50 years, 100 years, 200 years... Now project 50 and 100 years hence. Now 200 years. You can't conserve your way to that.
1 kilowatt, 5 kilowatts, 10 kilowats... The sun produces billions and billions of megawatts and hurls them all at us. Let's spend more effort learning how to catch them and use them.
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Re:I have my doubts... but, (Score:5, Funny)
I don't think so. I just chose a vacuum cleaner at random from a retailer web site and it uses 2000W
Pro Tip: turn off your vacuum cleaner when you go to bed.
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Hell no! (Score:5, Funny)
What are you trying to do, ruin my sex life?
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Re:I have my doubts... but, (Score:4, Informative)
I don't remember using KVA for any calculations in building houses, but here's what a typical house may have. (I'm like 15 years out of the business, so this is from rusty memory.)
My own house:
Outlets - generally 4-5 per circuit, about 8 sets.
8x20A circuits
Oh, plus 2 more for furnace and washer.
That's 10 20 amp circuits.
Then I have a range, dryer, an air conditioner and a heat pump with electric backup. That's a double pole 20, 3 30's, and a 40, all double pole for 240 volts.
That completely maxes out all the available slots in a 200 amp square-d main breaker box.
So while the actual use never meets the full potential, it has to be sized that way due to engineering and saftey codes.
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Re:I have my doubts... but, (Score:5, Interesting)
You pump water uphill during the day. Then at night, you let it fall downhill and generate electricity from that. We don't need fancy chemical tricks or storage mechanisms to make sporadic energy sources produce constant outputs.
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Re:I have my doubts... but, (Score:4, Insightful)
People often fail to realize the great energy density of gasoline and the amount of solar energy which hits a small area (such as the footprint of a car.)
My Honda accord has a footprint of 7 square meters.
IIRC the amount of solar energy reaching the Earth's surface at noon, at the equator is 1KW per square meter.
Assume a 8 hour work day, 50% efficient solar panels (better than current best), 100% efficient splitting of water and 1KW per square meter all the working day long.
That gives you 28 kilowatt hours worth of energy = 100,800,000 joules.
A gallon of gasoline contains 130,000,000 joules.
0.71 gallons of gas.
A more realistic scenario taking into account actual insolation (not my wacky 1KW the entire 8 hours) and the latitude most car owners live at gives us more like 400 watts per square meter (assuming you tilt the panels appropriately), 50% efficiency, 8 hours = 11.2 kilowatt hours = 40,320,000 joules = 0.31 gallons of gasoline equivalent.
Not only are there not many drivers who could commute on such little energy, the economic value of such small amounts would take a long time to offset up-front costs of the system.
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Re:I have my doubts... but, (Score:5, Informative)
Anyway, I guess where I was going with this is that this isn't some fuel pill, or Al Gore rambling on about things he doesn't understand. Nocera is to water splitting what Miyamoto is to video games, and if he says that he's done it, I'm sure he's done it.
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Re:I have my doubts... but, (Score:4, Insightful)
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Re:I have my doubts... but, (Score:5, Insightful)
Actually you can bike a lot further then you think. In addition it's not a waste of time in places with traffic congestion and you can travel faster by going a constant 15 mph as opposed to a stop and go 25mph. The roads would still exist obviously for an infinite amount of reasons but bike pathways and then offshoots of those pathways into may places of business would ease traffic and promote health and limit pollution.
Can you ride 30 miles to work in Texas without smelling so much like ass that you boss has to ask you to go home? Then, of course, ride 30 miles home where your wife has to hose you off before letting you in the house?
Oh, and then there is the rain, occasional ice, cold wind and so on that tends to inhibit normal people from riding bikes to work. Did I mention the hills? Lance Armstrong is from around here, ya know. Guess where he learned to ride up Mountains?
Of course, then we have to worry about how much stuff we can pack for the trip. First, we need a change of clothes so we don't smell like ass. Of course, we can't let them get wrinkled. Next, we need a towel to dry off with after we shower (assuming we have a shower at work). Of course, we'll need soap and shampoo to wash the sweat off. This doesn't include a notebook or briefcase that is required for work.
Now, of course, if we all lived downtown, it wouldn't be a problem. Unfortunately, because so many people want to live downtown so they can feel smug about riding their bikes to work that it has driven up the price of homes within bike distance of the jobs so much that it costs way too much for way too little living space. Sorry, but I don't make half a million a year, so I can't afford to live downtown.
So, forgive me if it seems as if I'm coming down on you. It's not just you, but everyone else who tells me how I too could ride my bike to work. But seriously, please, don't give that crap about how wonderful it is to live in a Utopian society where all our jobs are within 5 minutes of our homes. That's only the case in Tom Hanks/Meg Ryan movies and does not reflect reality. Also, don't get me wrong, I would love it more people rode bikes to work. That would free up the free ways so I could get to work in less than an hour. Of course, if that were the case, all the freeways would still be jammed they would all be one lane government works.
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Re:I have my doubts... but, (Score:5, Funny)
Also, don't get me wrong, I would love it more people rode bikes to work. That would free up the free ways so I could get to work in less than an hour.
You're not alone! A recent study by the American Public Transportation Association [theonion.com] found that 98 percent of Americans support the use of mass transit by others.
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Re:I have my doubts... but, (Score:5, Informative)
It's rather snotty to flatly contradict a statement you disagree with, and then claim to have "fixed" it.
-jcr
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Re:I have my doubts... but, (Score:5, Insightful)
I'd mod that +1 informative if I could... there's a lot of slashdot posters who don't seem to realize how rude it is... and how rudeness undercuts real discussion.
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Re:I have my doubts... but, (Score:5, Funny)
There, fixed that for you.
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Solar commuter cars won't work and here's the math (Score:5, Interesting)
Average commute is 15 miles.
Average electric car uses 300 watt/hours per mile (after recoving energy from braking)
Cost effective solar cells are 15%
Surface area of a car is 1.5 square meters.
Solar insulation is 1 kw/h for 5 hous a day (on average)
SOOO...
1.5 square meters * 15% * 1000 watts * 5 hours = 1125 watt/hours
The average commute is 15 miles * 300 watts-hours = 4500 watt/hours consumed.
Solar powered cars won't work until solar cell efficiencies are 50% or better.
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Re:Solar commuter cars won't work and here's the m (Score:4, Informative)
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Re:trade secret (Score:5, Informative)
The paper is published in a peer reviewed journal. It's patented, not secret.
They used ITO glass as an electrode with a neutral KPi electrolyte with 0.5mM Co^{2+} at 1.29V. They tried it with CoSO4, Co(NO3)2, and Co(OTf)2 as the cobalt source. It also works on FTO glass, as well as with a NaPi electrolyte.
The description of the processing method is extremely detailed. I would have little difficulty duplicating this experiment. (YIAAS)
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Wow (Score:5, Funny)
First open sourcing solaris and now this.
Way to go Sun!
Benefits not just solar . . . (Score:5, Insightful)
This would be a big win for any kind of "environmental" energy source (wind, waves, caged toddlers) that isn't always on.
Heck, it would make a great general-purpose home UPS and/or load leveler. If properly integrated, a home equipped with this would be less vulnerable to brownouts and blackouts. Local storage would make the job of power companies easier too.
Fingers crossed.
Re:Benefits not just solar . . . (Score:5, Funny)
>This would be a big win for any kind of "environmental" energy source (wind, waves, caged toddlers) that isn't always on.
Perhaps you've never seen a collection of caged toddlers. I assure you, they are always on.
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I have a toddler, trust me on this. ;) (Score:4, Interesting)
Not to mention, have you seen the waste products? I wouldn't call 'em "environmentally friendly"!
Actually the way the waste is treated now it's unsustainable. However it would be sustainable if that "waste" were composted and made into humanure [wikipedia.org]. If you garden, depending on what you grow in the garden, your plants will love you for watering them with your urine. Not straight mind you, nitrogen burn can kill them, but by mixing 10 parts water to one part urine. They would also love it if they were watered with greywater [wikipedia.org]. That's what I did for a while, my bathtub was clogged for a while before the owner sent a plumber. So I'd use the grey water from showering to water my garden. Those who have commented about the garden said it looks real good, another gardener asked how I got my tomato and tomatillo plants so big.
Falcon
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If this is true... (Score:5, Interesting)
What are the implications for things such as water purification, desalination, etc?
Seems like a fuel cell "battery" is just the tip of the iceberg.
Re:If this is true... (Score:5, Interesting)
I was thinking the same thing. I'm imagining a partially-self-powering desalination setup that cycles through seawater (filtered for particulates), extracts the hydrogen and oxygen, combines it in a fuel cell (which power is then cycled back into the system), then stores the resulting water for later drinking or irrigation.
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Re:If this is true... (Score:5, Informative)
My experience is that when you try to use electrolysis on salt water you get NaOH and chlorine.
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no more caustic substances needed! (Score:5, Funny)
Now we only have to solve the problem of storing a very flammable gas and possibly an incredibly powerful oxidizer!
This Quote made the story, (Score:5, Funny)
Scientist and Gamer...
Great. So when do we see it? (Score:5, Insightful)
According to Reuters, the discovery of the a new catalyst for separating hydrogen+oxygen from water requires only 10% of the electricity of current methods
Great. So when do we see it? If it's anything like almost every other "alternative energy" advancement, it will either get snapped up by an oil-company owned holding company, or strangled by licensing fees/requirements/exclusivity deals.
Seriously- let's take a look back. Have there been any major advancements in solar energy technology in the last fifty or so years?
MIT = MIT Technology Licensing Office, and I used to work there. Six figure checks to professors were not uncommon...and it was the only part of the university that turned a profit.
It'd be really refreshing to see scientists develop a bit of altruism. It's the ultimate Open Source, and they'd be guaranteed decades, if not centuries, of good will and fame. That's worth a lot more than a few *possible* royalty checks.
Re:Great. So when do we see it? (Score:5, Insightful)
>> It'd be really refreshing to see scientists develop a bit of altruism. It's the ultimate Open Source, and they'd be guaranteed decades, if not centuries, of good will and fame. That's worth a lot more than a few *possible* royalty checks.
Altruism neither pays for the scientists' mortgages nor pays for all the equipment they use to develop their theories.
I'm all for smacking down ridiculously-long copyrights, invalidating silly trademarks or getting rid of obvious patents (one-click shopping?), but this is the _exact_ thing that patents is supposed to support. These scientists (and by proxy, their granteurs (sp?)) took a gamble on developing a technology and they were successful. They should be rewarded for that success like any other person in society. Without that potential for gains, there's no reason to even try.
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Since 1958? (Score:4, Informative)
50 years ago was 1958. Interestingly enough., that was the year the first solar panels went to space. Today, you can sit right there in your chair, do some googling, whip out your credit card and have dandy solar panels shipped right to your house at less than NASA cost plus pricing levels. That's pretty significant. A few years previous to that, some of the first ones were running $1,785 dollars per watt, and those are unadjusted dollars. Today you can look for deals and get them at around 5 bucks a watt. Not too shabby. And nanosolar started shipping this year, albeit all of it to Germany where demand is higher and they will pay a bit more now, because they know conventional will be going up fast later, so they did a whole nation push for it starting some years ago. That and it is cleaner.
here's the wiki ref for the figures, Solar timeline [wikipedia.org]
I bought mine at actually a little under 5 bucks a watt some years ago. silicon demand has been going more for throw away gadgets and so on in the meantime, but several new fabs go online this year and next year so prices will be dropping again.
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Re:Gimme a break (Score:5, Interesting)
Large format NiMH batteries.
Marketed as the Panasonic EV-95. Or rather, not marketed. You can't buy them. The only vehicles they are currently in now (no pun intended) are three hundred some-odd Toyota RAV4-EVs.
If they are ever sold for use to power traction motors in an electric vehicle, Cobasys will slap Panasonic with an injunction to stop. And you can't buy them at any price other than in very large quantities, and the only people who can buy such large quantities are automakers. Some would say "Not a scam" but the licensing of the technology to exclude certain forms of transportation is REAL.
Who's Cobasys? Just the joint venture between the inventor of the battery, ECD Ovonics, and -- wait for it -- Chevron.
Here are a [investorvillage.com] few [autobloggreen.com] citations and examples. [wikipedia.org] Although things seem to be getting better, as they are being licensed in some hybrids now, and they may be expanded to more applications in the future...
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Re:Gimme a break (Score:4, Informative)
The Cobasys example is bullshit. I admire your integrity in agreeing that it's a bullshit example, by citing the fact that they are used in hybrids (although you also lie about them only being in RAV4 EVs), but am puzzled at your inability to reconcile that fact with your lie about it being supressed. So they don't want to sell piddly quantities to shadetree mechanics. So what. They ARE selling to automakers, while you claim they aren't.
Try again.
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ENVIRONMENTAL RECKLESSNESS (Score:5, Funny)
It is established FACT that Hydrogen is very difficult to contain. It leaks through the tightest seals like they were swiss cheese, and once free it races into the atmosphere and escapes into space.
This is not a major problem when all our hydrogen comes from the deep deposit hydrogen mines in Australia and Canada, but what if this new discovery hearalds an age of wholesail water mining? Do these so-called scientists not realise that we cannot have water without hydrogen? Have they forgotten that humans are 80% water? That water makes our crops grow and our fish swim?? Our life's blood could be literally floating away!
This irresponsible god-gaming may save us from peak oil today, but our grandchildren tomorrow will be facing PEAK WATER if these experiments are allowed to continue!
Write to your political representative today!
self-repairing catalyst (Score:4, Informative)
If you read the actual article (you need to be a AAAS member or otherwise have access to Science), you would see that that these MIT guys are using a cobalt oxide catalyst which is created during the electrolysis of water. Yeah, it's really efficient, which is good (I don't know that I buy the green thing), but it's also self-repairing. Although it seems to be future work, they're envisioning tailoring the chemistry so that the activity of the catalyst is maintained by an equilibrium of dissolving and redeposition of the catalyst electrode. As a bonus, it looks really easy to make.
Re:Good solution but wrong problem. (Score:5, Insightful)
Why would you want to provide hydrogen for powering vehicles if you've got such great batteries?
Because batteries aren't so great. They're only reasonably efficient when they're nice and warm, they're heavy, they're expensive, and they wear out fast.
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