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Micromotors Race About By Turning Water Into Hydrogen Gas

Unknown Lamer posted about a year and a half ago | from the don't-let-krycek-get-any dept.

Medicine 85

MTorrice writes "Microscopic particles of aluminum and gallium rocket around using water as their fuel. The particles, which are 20 micrometers in diameter, are asymmetric: A chemical reaction on the back side of the particle forms hydrogen gas bubbles that propel the motor forward. Over the past several years, bioengineers have built micro- and nanosized rockets that zip through liquids, fueled by chemical reactions between the materials that make up the rockets and their environments. The engineers hope someday these tiny motors could help deliver cargo, such as drugs, in people. Unfortunately, many of these motors require toxic hydrogen peroxide as fuel source, limiting their use in the body. To overcome that constraint, the new micromotors harness a well-known reaction between aluminum and water to produce hydrogen gas."

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85 comments

Similar to burning farts. (-1)

Anonymous Coward | about a year and a half ago | (#41145405)

I sometimes have a chemical reaction on the backside of my ass that propels me forward.

Where has the Oxygen gone to ? (2)

Taco Cowboy (5327) | about a year and a half ago | (#41145451)

If the rocket blurbs out H2 and the backends, and as I understand, water is made of 2 Hydrogen and 1 Oxygen (H2O), where has the Oxygen gone to?

Re:Where has the Oxygen gone to ? (0)

Anonymous Coward | about a year and a half ago | (#41145483)

Wherever it wants.

Re:Where has the Oxygen gone to ? (5, Informative)

Anonymous Coward | about a year and a half ago | (#41145511)

Aluminum oxide byproduct.

I've been familiar with this reaction for awhile. You can see youtube videos of it. Gallium is expensive but can be recycled from the waste making the process a fairly reasonable method of transporting energy in a lightweight, and compact way.

This is a clever application and I will keep it in mind as a "gas generator", rocket, or source of pneumatic pressure.

Re:Where has the Oxygen gone to ? (1)

circletimessquare (444983) | about a year and a half ago | (#41145649)

Aluminum hydroxide is where it goes

Followup question: Why doesnt my bike do the same? (0)

Anonymous Coward | about a year and a half ago | (#41146327)

It’s also made of aluminium. I drive it in the rain. It doesn’t rust (aka oxydize). Does it?

Re:Followup question: Why doesnt my bike do the sa (4, Informative)

Anonymous Coward | about a year and a half ago | (#41147225)

Actually aluminium does rust. But unlike iron rust, aluminium oxyde produces a solid and stable surface

Re:Where has the Oxygen gone to ? (4, Funny)

jellomizer (103300) | about a year and a half ago | (#41147107)

Two guys walk into the bar. They have both lost all their money in a bad divorce. The bartender goes to them what will you have.
The first man goes Ill have some H20, the second man said Ill have some H20 too.
The second man died shortly afterwards with a foaming mouth.

20m in diameter (3, Funny)

snowraver1 (1052510) | about a year and a half ago | (#41145411)

I don't know bow it's administered, but I'd rather die...

Re:20m in diameter (4, Informative)

Unknown Lamer (78415) | about a year and a half ago | (#41145463)

Slashdot's lack of unicode support strikes again! There should have been a mu there, oops.

Re:20m in diameter (4, Insightful)

mark-t (151149) | about a year and a half ago | (#41145543)

Which raises an excellent point, really. Why does a technical oriented site such as this *NOT* support unicode?

Re:20m in diameter (2)

Unknown Lamer (78415) | about a year and a half ago | (#41145679)

Engineering time and it started life as perl written in 1997 by a college student.

Re:20m in diameter (4, Funny)

ChatHuant (801522) | about a year and a half ago | (#41145855)

Engineering time and it started life as perl written in 1997 by a college student

That makes sense - how can anybody complete a new feature with only fifteen years of development?

Re:20m in diameter (2)

VortexCortex (1117377) | about a year and a half ago | (#41146275)

I know, right? I mean, if only the supporting platforms slashcode runs on were compatible with Unicode. Why, then instead of cocking up UI with some new Web 2.0 BS, they could have just modified their code to add the feature. ::sigh:: Once again, blame Micro$oft!

Re:20m in diameter (1)

TubeSteak (669689) | about a year and a half ago | (#41146277)

I wonder if the Geek.net overlords have implemented unicode support at SourceForge or Think Geek.

Re:20m in diameter (1)

BitterOak (537666) | about a year and a half ago | (#41153703)

Engineering time and it started life as perl written in 1997 by a college student

That makes sense - how can anybody complete a new feature with only fifteen years of development?

True. That's only about as long as Perl 6 has been in development.

Re:20m in diameter (0)

Anonymous Coward | about a year and a half ago | (#41145681)

Because expecting even a basic level of competency from the people who run slashdot is asking far, far too much? Even dead simple shit like spell- and grammar-checking submissions (let alone fact-checking) is apparently far too much to expect for one of the most prominent "edited" tech news sites.

Re:20m in diameter (1)

Anonymous Coward | about a year and a half ago | (#41146259)

I actually asked CmdrTaco this, and his stupid excuse was, that you couldn't keep things secure with all those special control characters and stuff.

Which is bullshit, because
1. ASCII also has control characters (<0x20)
2. Unicode specifically has a nice separation of types of characters into different blocks. And there are tons of tables online on which are which. Hell, Regex even has complete Unicode-compatible character classes to make this separation. So one only needs to filter all chars in non-allowed classes, or manually allow only certain blocks. Easy. I’ve done it myself in the past. Done in an evening. And 100% guaranteed to be secure, since the only allowed blocks will never magically get weird shit.

I’ve come to the conclusion, that CmdrTaco just doesn't give a shit. (Guess even he considers the site not worth the effort anymore. :/)

Re:20m in diameter (1)

alexgieg (948359) | about a year and a half ago | (#41147203)

I’ve come to the conclusion, that CmdrTaco just doesn't give a shit. (Guess even he considers the site not worth the effort anymore. :/)

I don't know Perl beyond the basics, but I'm going with a wild guess that, over the years, there's at least some thoroughly tested, debugged and properly secured Unicode libraries out there able to replace whatever crazy REGEX runs behind /.'s code, probably with minimal effort.

On the other hand, I can also see how converting the huge text database might make things somewhat more difficult, or at least time consuming, take for instance that time when the number of comments hit the 32-bit limit in the DB's index column and they had to update it to 64-bit. If I remember correctly, adding new comments had to be suspended for a few days. Compared to updating the all text fields' character set/collation from (presumably) latin1_generic to utf8_unicode (one never, ever, should use the utf8_generic hack when seriously going about supporting Unicode), that simpler index conversion would feel like a walk in the park.

Re:20m in diameter (0)

Anonymous Coward | about a year and a half ago | (#41147991)

Given that in the past, Slashdot did accept Unicode (and it was more or less disabled after someone misused some control characters) I'd say that the fundamental support should be there.

And BTW, the mu character is in the basic ISO-8859-1 (aka latin1) character set. Not allowing even that is even more annoying than not allowing Unicode in general.

Re:20m in diameter (1)

ryzvonusef (1151717) | about a year and a half ago | (#41163583)

I’ve come to the conclusion, that CmdrTaco just doesn't give a shit. (Guess even he considers the site not worth the effort anymore. :/)

Yeah... I heard he hasn't even come to office for the past year....

Re:20m in diameter (1)

StripedCow (776465) | about a year and a half ago | (#41146925)

Because it is not fun to rewrite your entire codebase to deal with unicode?
And it is even less fun to rewrite only a part of your codebase if you can't use typechecking to keep the two "domains" apart.

Re:20m in diameter (2)

interkin3tic (1469267) | about a year and a half ago | (#41145655)

Indeed, crossbow, recurve, compound... just seems unnecessary.

In other words "Ha ha! You were making fun of a type o and you yourself made a type o!"

20 m? (-1)

Anonymous Coward | about a year and a half ago | (#41145413)

another copy/paste error?

do we know editor or submitter isn't designing next Mars mission?

20 m diameter particles? (1)

QQBoss (2527196) | about a year and a half ago | (#41145449)

"The particles, which are 20 m in diameter, are asymmetric..."

Where I come from, 20 meter diameter anythings would rarely be considered particles!

so... (-1, Troll)

notgm (1069012) | about a year and a half ago | (#41145457)

these motors do work, while creating fuel?

riiiiiight.

Re:so... (3, Informative)

Rosco P. Coltrane (209368) | about a year and a half ago | (#41145475)

Read TFA - or heck, even just the /. blurb, and you'll see aluminum is consumed in the reaction to produce hydrogen. It's not free energy.

Re:so... (1)

notgm (1069012) | about a year and a half ago | (#41147739)

my point is that it's poorly reported. there's no mention of how much aluminum it takes to make hydrogen, nor how much hydrogen one might expect from the process.

Re:so... (1)

nedlohs (1335013) | about a year and a half ago | (#41145491)

No, they use fuel like everything else. You know as clearly stated in the article and the summary.

Re:so... (-1, Troll)

notgm (1069012) | about a year and a half ago | (#41145599)

i did rtfa, and rtfs. neither speaks to the amount of fuel the motors take in, nor the amount of hydrogen produced.

Re:so... (1)

nedlohs (1335013) | about a year and a half ago | (#41152557)

TFS: a well-known reaction between aluminum and water to produce hydrogen gas

TFA: 2Al + 6H2O -> 3H2 + 2Al(OH)3 (with correct subscripting in the article...)

I guess "well known" would depend on the population you are refering to, but anyone who has done any chemistry must have done that one.

Re:so... (2)

kasperd (592156) | about a year and a half ago | (#41148409)

You know as clearly stated in the article and the summary.

The summary gives the impression that aluminium acts as catalyst in a chemical reaction that produce bubbles of hydrogen by consuming water as fuel. But we know that cannot be true, as that would imply they are extracting energy from an endothermic reaction.

More likely it is actually consuming aluminium as fuel and using water as oxidant. But that is certainly not clearly stated in the summary.

Re:so... (1)

nedlohs (1335013) | about a year and a half ago | (#41152607)

"reaction between aluminum and water" means what it says.

Re:so... (1)

kasperd (592156) | about a year and a half ago | (#41154307)

"reaction between aluminium and water" means what it says.

But since it only said that the water acted as fuel, the aluminium must play a different role in the reaction. That's why I think it gives the impression the aluminium is a catalyst in the reaction.

Re:so... (0)

Anonymous Coward | about a year and a half ago | (#41145713)

Yep, just like nuclear power plants do. On man's nuclear waste is another man's reprocessing fuel.

side effects include Spontaneous Combustion (3, Funny)

aapold (753705) | about a year and a half ago | (#41145527)

...just not widely reported

Re:side effects include Spontaneous Combustion (1)

DrEnter (600510) | about a year and a half ago | (#41149349)

I know it's ridiculous, but my first thought when I read this was an image of over-inflated hospital patients ballooning into the sky and bursting into flames with cries of "oh, the humanity!" I need to watch less TV.

Hydrogen fuel (2)

riverat1 (1048260) | about a year and a half ago | (#41145541)

is this something that could be used to cheaply make hydrogen for fuel? If you put 6.02 * 10^23 of them in water how much hydrogen would it produce?

Re:Hydrogen fuel (2)

Ignacio (1465) | about a year and a half ago | (#41145561)

Not enough to replenish the energy consumed by the aluminum production process.

Re:Hydrogen fuel (1)

rossdee (243626) | about a year and a half ago | (#41147451)

Speaking of the laws of physics - the GOP are having their convention right now, have they said that they are going to repeal the laws of thermodynamics?

Re:Hydrogen fuel (0)

Anonymous Coward | about a year and a half ago | (#41147745)

What? It's the Democrats that say they can stimulate the economy by taking money out of the economy via taxes and then putting the money back in via government spending, minus a 50% loss or so due to bureaucracy and waste, yet somehow still come out ahead.

Economics is just like thermodynamics - there ain't no such thing as a free lunch.

Re:Hydrogen fuel (0)

Anonymous Coward | about a year and a half ago | (#41158695)

Economics is abstract. Money is man made, so the only laws it needs to obey are those made by man. In fact, if we didn't make money in the first place it wouldn't exist at all, so creating more money doesn't break any laws, as long as you're the government. Physical laws are a bit different.

Re:Hydrogen fuel (1)

JSBiff (87824) | about a year and a half ago | (#41148763)

How does this compare, efficiency-wise to other processes for hydrogen production? If you had another source of energy (nuclear, solar, etc), and were interested in converting that energy to hydrogen (perhaps to then synthesize something like ammonia or di-methyl ether), would this be an efficient way to go about it?

Re:Hydrogen fuel-Looking forward to the car (5, Interesting)

GoodNewsJimDotCom (2244874) | about a year and a half ago | (#41145623)

You're better off buying an electolyzer for $150-$1000. Electrolyzer required distilled water. Distillers are pretty cheap too, lets say you can get one for 150$.

Now the cool thing coming out is Toyota's Hydrogen Car for 50k or so in 2015. In order to store hydrogen in a tank, you must first compress it. Hydrogen is a material that erodes a lot of materials it comes in contact with, so dealing with it is somewhat more challenging than other fuels. Compressors exist for hydrogen, but I couldn't find a price for under $12k. Before I become a hobbyist in this, I need to make sure I can afford it, and $12k for the compressor is what makes working on a personal hydrogen refueling station unfeasible for me.

I think if hydrogen car economy takes off, everyone will have their own refueling station because the only two inputs required are: Electricity and Water. Then you lose some power converting the electricity into hydrogen but being able to store it in fuel tanks as opposed to expensive batteries that wear out makes it nice. We're looking forward to time where people invest in their own solar panels on their property so they pay less in utilities too.

I think in the short run of a hydrogen economy, you'll have hydrogen refueling stations, but in the long run, people will be making personal stations too. Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline. Of course if the price of the car is greater than the price of a gas powered car and its lifetime of gasoline, there is only going to be a niche market. But if Toyota can get these things for under $25k and they don't have any serious downsides like the electric car's problem of battery arrays dying.... It could be the future.

Because of this, I want to become a hobbyist, and maybe own my own refueling station some day, but I don't want to get too involved if I can't afford a hydrogen compressor. Anyone know of a place to get a hydrogen compressor for under $12k?

Re:Hydrogen fuel-Looking forward to the car (3, Informative)

jenningsthecat (1525947) | about a year and a half ago | (#41146371)

Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline.

Only if the cost of the electricity used to hydrolyze the water is also extrememly low. For the foreseeable future, the only viably-large source of electricity that is close to carbon neutral will likely be nuclear power - sun and wind likely won't be sufficient for a long time. Also, power from sun, wind, and fission are currently priced artificially higher than power from oil, because with oil we're 'borrowing' from future generations to support our extravagant lifestyle but aren't even calculating the principal, never mind the interest...

I'm all in favour of building 'hydrogen economy' vehicles and infrastructure right now, even though it's not yet clear exactly how we'll come up with enough clean energy to justify it, unless we go all-out nuclear, the prospect of which scares the sh*t out of me. But let's be VERY clear that in the short term we may in fact be increasing carbon emissions by doing so. There are WAY too many people out there who see zero emissions at the tailpipe and think the problem is solved, when in fact total emissions per mile driven may well be higher than those produced by a gasoline engine. Joe Public needs to be educated about such things, and the makers of various 'environmentally friendly' technologies aren't about to do that if it risks harming their sales. We in the tech and scientific communities have an obligation to start getting the word out that There Ain't No Such Thing As A Free Lunch.

Re:Hydrogen fuel-Looking forward to the car (2)

codman1 (904493) | about a year and a half ago | (#41146409)

Using Electrolysis is very energy inefficiently, that why its only worth it in certain places eg. over production in nuclear power plants or on very small scales such as Labs. The gallium is used as a catalyst for the reaction the pure aluminium is used and turned into aluminium oxide which can be recycled using the over production of power in nuclear power plants. The other key component is the water which is probably better to use distilled but not critical as any mineral deposits can be reprocessed during the recycling of the gallium and alu-oxide. As the distillation process also uses power and quite a lot of it the use of Electolyzer/Electrolysis will not be a big part of the Hydrogen Fuel economy - its not efficient enough. Currently our best hope for cheap carbon effiecnt energy is small scale SSTAR rector's (2015 ish), if you deffo want Hydrogen power then currently the low cost of gallium/alu production seems very good, with very few long term draw backs. IMHO

Re:Hydrogen fuel-Looking forward to the car (1)

Kokuyo (549451) | about a year and a half ago | (#41146559)

Instead of stepping up the hydrogen/fuel cell business (which needs two additional conversions of energy), why not just put more effort into better batteries and do away with all that expensive and probably large equipment and put the electricity to work directly?

I really don't get hydrogen proponents...

We need three things from batteries:
- Longer life
- Faster recharge
- More storage

And in a lot of situations, a bit of organizational talent helps to work around some, if not most, of an all electric car's limitations. A Tesla Model S can go almost 500km. How many people do you think will have to go more than 500km in one day on a regular basis?

Sure, we can't replace ALL other vehicles with all electric cars right now, but if we could replace 60%, imagine what that would do to our CO2 budgets. Unless, of course, we've been burning fossil fuels to make electricity.

If I could afford a Model S, I'd by it. But then again, I go to work mostly by bike or motorbike, so my gasoline abuse is rather limited as it is.

Re:Hydrogen fuel-Looking forward to the car (2)

Kokuyo (549451) | about a year and a half ago | (#41146603)

I just googled a random factlet: It says, refining a gallon of gasoline uses between 4 and 7.5kWh.

So a Model S can go 500 km on 85kWh which means it can go 23.5 km per kWh (assuming refining used 'only' 4kWh) and thus per gallon.

As a comparison, a 2 litre Audi A6 gets 28 MPG. that's about 48 km per gallon.

So you might say, hey, the gas engines are actually better! You'd be wrong.

This means that half the electricity a Model S uses, is used anyway by a gas engine! This means, if we switched over to all electric cars, only 50% of the needed electricity would have to be produced on top of what we're doing today, because the other 50% already go into gas production, right now.

Also, if you take the 7.5kWh number, you get a number of 44 km to the gallon for a Model S and that is RIGHT THERE with what an Audi uses. Only without burning even a cup of fossil fuels.

Sure, a Model S is not magically environmentally friendly. These batteries aren't all fairy dust and laughter to recycle, but heck, I thought CO2 was our major problem. Let's solve it.

Re:Hydrogen fuel-Looking forward to the car (1)

Kokuyo (549451) | about a year and a half ago | (#41146607)

D'uh, sorry people, I seem to be not quite all there right now... of course it's not 23.5 km per kWh at all... but the per gallon part should be correct, I hope...

Re:Hydrogen fuel-Looking forward to the car (1)

gl4ss (559668) | about a year and a half ago | (#41146683)

you still need cheap energy for the both.

what good is a hydrogen station when cheapest way to get hydrogen is from gasoline??

Re:Hydrogen fuel-Looking forward to the car (0)

Anonymous Coward | about a year and a half ago | (#41148225)

Because quite soon, the cheapest way to get hydrogen will not be gasoline, and therefore you'll have an advantage if you are already able to use non-gasoline energy sources?

Re:Hydrogen fuel-Looking forward to the car (1)

GoodNewsJimDotCom (2244874) | about a year and a half ago | (#41154767)

The easiest way is just use electricity off the grid. I've heard, but not confirmed it is around an order of magnitude cheaper than gasoline to electrolyze hydrogen. This sounds reasonable because the electric cars also have cheap fuel from electric.

Of course if you have a place for a lot of solar/wind farms, they can pay for themselves in 5-10 years with tax credits just on one's own home. So if you're making hydrogen for a refueling station, you could probably charge 1/3 what a gasoline station charges for the equivalent of a gallon, and everyone is happy, and you're making a good profit to recoup your solar investment and scale up your operations more.

What I am doing as a hobby is that once I find a cheap compressor: I'm simply going to start making and selling pressurized hydrogen and maybe distilled or mineral water privately until the electric car comes out. It is just a hobby I want to get into because the future might be promising.

Re:Hydrogen fuel-Looking forward to the car (2)

Solandri (704621) | about a year and a half ago | (#41147037)

I think if hydrogen car economy takes off, everyone will have their own refueling station because the only two inputs required are: Electricity and Water. Then you lose some power converting the electricity into hydrogen but being able to store it in fuel tanks as opposed to expensive batteries that wear out makes it nice.

Problem is hydrogen sucks as a fuel. It's not just the density/compression and corrosive problem you described. H2 molecules are tiny - about the smallest molecule there is (only a few monoatomic elements are smaller). Tanks and pipes which are watertight and airtight are not necessarily hydrogentight. Storage tanks, delivery trucks and pipelines, and hoses for fueling your car will all leak hydrogen.

Why deal with hydrogen as a fuel with its huge storage, transportation, and delivery problems? Just combine it with some other elements to get a different molecule which is much more manageable at standard temperature and pressure. Most of the focus right now is on methane, but there are liquid compounds as well. The most common is petroleum (which would bring us full circle), but alcohols have nearly as high energy density as gasoline while burning much more cleanly. And you can create alcohol through decomposition and fermentation of plant matter - biofuels.

Hydrogen makes sense for rocket launches because rockets are extremely weight-sensitive, and hydrogen has extraordinarily high energy density per mass. But its volumetric density, corrosive nature, and tendency to leak represent huge engineering challenges for using it as a general purpose fuel. Why bother? So you can brag you're burning a fuel which only produces water as a byproduct? That's only true if you completely ignore the process by which you generate the energy needed to manufacture the hydrogen fuel in the first place.

Re:Hydrogen fuel-Looking forward to the car (1)

Ignacio (1465) | about a year and a half ago | (#41157093)

What we need is a cheap and cheesy way to make nitromethane in bulk. No idea how, but that would solve several problems at once.

Re:Hydrogen fuel-Looking forward to the car (0)

Anonymous Coward | about a year and a half ago | (#41147199)

in the long run, people will be making personal stations too

I'm not sure I want to live next to anyone who has built their own plant to produce and compress hydrogen, but thanks anyway.

Re:Hydrogen fuel-Looking forward to the car (1)

tchall (1146319) | about a year and a half ago | (#41152539)

I think in the short run of a hydrogen economy, you'll have hydrogen refueling stations, but in the long run, people will be making personal stations too. Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline.

Aside from the unintended consequences of adding tons of water vapor to the atmosphere it's a great idea

Increasing concentrations of the most powerful greenhouse gas, increased precipitation over the most populous regions of the world, and local climattic changes like Phoenix AZ's humidity increase that no longer allows the use of cheap evaporation coolers... are ALL easily projected results

Considering that doing this today will require massive use of fossil fuels, and future expansion will require potentially ecologically damaging processes to produce solar panels the "carbon footprint" of massive hydrogen production/use might worsen any AGW effects...

Because of this, I want to become a hobbyist, and maybe own my own refueling station some day, but I don't want to get too involved if I can't afford a hydrogen compressor. Anyone know of a place to get a hydrogen compressor for under $12k?

I'm sure someone will find you a compressor the markets always respond to demand... especially for clean, nearly free energy sources...

Re:Hydrogen fuel (5, Informative)

Solandri (704621) | about a year and a half ago | (#41146953)

There's no such thing as a free lunch. Any energy you hope to get out of burning hydrogen as a fuel has to have been put into it first. The key concept you're looking for is Gibbs Free Energy [wikipedia.org] - a measure of the chemical energy potential of a mole of molecules. H2 and O2 have fairly high Gibbs free energies, while water is very low. So combining H2 and O2 to make H2O releases a lot of energy. But converting H2O back into H2 and O2 requires just as much energy as was released (more in fact, due to inefficiencies). There's no shortcut, as that would violate conservation of energy.

The only way to cheaply make H2 for fuel is to use substances which start off with high Gibbs free energies. You're probably familiar with many of them - methane, propane, various petroleum products, as well as alcohols and sugars/wood. Converting these substances to H2 for fuel is pretty much the same as burning them in an internal combustion engine, except with additional intermediate steps and huge storage, transportation,and delivery complications. There's an advantage in that there's no pesky carbon, nitrogen, and sulfur in the second step (hydrogen -> water) so we don't get CO2, nitrous oxides, and sulfides as byproducts. But you still need to deal with those byproducts in the first step (fuel -> hydrogen). So it's questionable whether the tradeoff is worth it.

Incidentally, this is why many people refer to hydrogen as a battery, not a fuel. Raw hydrogen gas is pretty much non-existent on this planet. So you're not getting free energy from the hydrogen. You're taking energy from other sources (burning coal or petroleum, nuclear, hydro, wind, solar) and storing it by converting something into hydrogen gas, then releasing that energy when you burn the hydrogen (well, releasing what's left after efficiency losses). Any energy calculation of the hydrogen economy has to take into account the efficiency losses due to this multi-step conversion process. It's almost bad enough to knock a hydrogen fuel cell car's efficiency down to the efficiency of an ICE gasoline car. (60% efficient fuel cell * 60% efficient hydrolysis = 36% efficiency. Modern ICEs are close to 30% efficient.)

In TFA's case, the energy used to convert aluminum oxide into metallic aluminum is used to liberate the H2 from the H2O (the Al being converted to Al2O3 by the extra oxygen in the process). So it's almost certainly wasting more energy than if you just did straight electrolysis on the water. The only benefit is that aluminum is very compact and easy to handle as a fuel source, much more so than hydrogen or storing electricity in a battery.

Cave Johnson Here! (3, Funny)

Cylix (55374) | about a year and a half ago | (#41145577)

If you've cut yourself at all in the course of these tests, you may have noticed that your blood is pure hydrogen- that's normal. We've been shooting you with an invisible micromotor that's supposed to turn blood into hydrogen, so all that means is it's working.

Re:Cave Johnson Here! (1)

redback (15527) | about a year and a half ago | (#41145815)

Notice how nobody panics if everything goes according to plan, even if the plan is horrifying

Toxic hydrogen peroxide? (0)

Anonymous Coward | about a year and a half ago | (#41145609)

Since when has hydrogen peroxide been toxic?
To this day, I still pour it on my cuts to help clean the wound before applying antibiotic ointment and bandages.

can't tell if you're serious (4, Informative)

Chirs (87576) | about a year and a half ago | (#41145749)

Why do you think it kills the germs in a cut?

Toxic yes, hazardous less so (4, Informative)

Beryllium Sphere(tm) (193358) | about a year and a half ago | (#41145767)

Notice how it foams up as soon as it hits blood? Blood is full of peroxidase. Breaking down hydrogen peroxide into water and oxygen is routine housekeeping, since your body actually produces hydrogen peroxide as a weapon for the immune system to use.

So: toxic, but gets detoxified almost instantly, and anyway wouldn't it be in the equivalent of a fuel tank?

Re:Toxic hydrogen peroxide? (1)

c0lo (1497653) | about a year and a half ago | (#41145765)

Since when has hydrogen peroxide been toxic? To this day, I still pour it on my cuts to help clean the wound before applying antibiotic ointment and bandages.

A concentrated solution of alcohol would also act as disinfectant (highly hygroscopic, extracts water from cells, kill germs)... but would still be toxic ingested in certain amounts or injected straight into the blood stream.
As to why hydrogen peroxide is toxic [wikipedia.org] - capable of generating atomic oxygen and free radicals. While on external wounds it's beneficial (degrades the proteins, accelerates coagulation), one wouldn't like this to happen inside the body.

Re:Toxic hydrogen peroxide? (2)

shaitand (626655) | about a year and a half ago | (#41147729)

Your body produces hydrogen peroxide directly in the bloodstream on a fairly regular basis. Nature produces it on a far more regular basis. Rainwater contains hydrogen peroxide. Our body evolved in the presence of this substance. Although it reacts with cells we are talking about seemingly random cells in very tiny quantities and byproduct is oxygen which bonds pretty much immediately with hemoglobin. The body certainly has no trouble replacing cells that belong but won't replace any toxins or byproducts that the peroxide has reacted with.

I'm sure we all know at least one person who takes the stuff regularly for 40+ years. I wouldn't recommend it. Peroxide does kill cells, necessitating replacing cells, increasing the need to replace those cells, and therefore increasing the likelihood of copying errors which lead to aging and possibly even cancer.

That said the idea that short term use of some dilute form of hydrogen peroxide is toxic is ridiculous. Because a few quacks pitched it as a the miracle cure for everything the medical establishment has built the stuff up as the devil. It's a shame because peroxide has many potential internal medical uses. For instance a round of inhaled hydrogen peroxide can help remove tar build-up in a smokers lung. Or a current smoker can use it periodically to help remove the tar their body has difficulty with naturally and possibly stop a great deal of the damage they are doing. Peroxide is definitely a safer route with fewer side-effects than chemo for killing cancer and can even be injected directly into a tumor making it a far more targeted treatment. In small quantities peroxide in the bloodstream acts as sort of molecular polish that reacts with arterial build-up. Like smokers, fast food junkies might be better off having periodic treatments with peroxide than not.

Spontaneous combustion.... (1)

macraig (621737) | about a year and a half ago | (#41145635)

I don't think I'd want a bunch of micro-rockets in my blood stream blowing hydrogen bubbles. What happens when I get cut next to someone smoking or a stove with all that hydrogen in my veins?

Finally the Water-powered car is a reality. (0)

Anonymous Coward | about a year and a half ago | (#41145685)

Micrometers in size, you say?

Eh, with the way parking spaces keep shrinking, I'm sure it'll work out.

Still better than the Flintstones method.

Aluminium is the fuel, not water (5, Informative)

hkultala (69204) | about a year and a half ago | (#41145687)

argh, again this kind of misleading headline that makes the people who only read the headline think a perpetual machine is finally invented.

The energy comes from aluminium, aluminium "burning" into aluminium-oxide.

Putting the "converting water into hydrogen" into headline is misleading reporting.

Re:Aluminium is the fuel, not water (1)

ThatsMyNick (2004126) | about a year and a half ago | (#41145851)

Yeah "converting water into hydrogen by burning aluminum" is a more appropriate summary.

Re:Aluminium is the fuel, not water (1)

RNLockwood (224353) | about a year and a half ago | (#41149285)

"Putting the "converting water into hydrogen" into headline is misleading reporting."

Yes, but it's great misleading reporting since it implies the fission of oxygen and the fission products all the way down to hydrogen. That's a somewhat endothermic process (cough, cough). Who needs to read the article with that great title?

That's like saying petrol cars run on air (1)

giorgist (1208992) | about a year and a half ago | (#41146025)

That's like saying petrol cars run on air. It's not just water, you also need Aluminium.

nano drug trafficking (1)

molecular (311632) | about a year and a half ago | (#41146507)

"The engineers hope someday these tiny motors could help deliver cargo, such as drugs. "

lol. nano-drug-trade. "BTC received, sending off ten billion bots with the coke tonight, expect bell-curve delivery tommorow around noon"

Hydrogen Peroxide not toxic (0)

Anonymous Coward | about a year and a half ago | (#41146873)

Hydrogen peroxide (H2O2) is not toxic. It decomposes on contact with organic matter into water (H2O) and oxygen (O2). The catalytic reaction releases heat and converts the water to steam. In such micro sizes and amounts the heat is not much and may not even be steam for more than a nanosecond. You can drink the output.

Its propulsive uses derive from the conversion from a high density liquid to a gas. In large quantities the power efficiency is about 113 lb-sec/lb (ISP).

The pain! The pain! (1)

cvtan (752695) | about a year and a half ago | (#41146971)

Please stop saying things like, "using water for fuel..."!!!!! Water is not fuel any more than the ashes from a wood fire are fuel.

why can't they use this to make helium? (1)

jsepeta (412566) | about a year and a half ago | (#41147399)

Since the world is running out of Helium supplies, it would be nice if scientists could develop ways of generating helium from micromotors.

Re:why can't they use this to make helium? (0)

Anonymous Coward | about a year and a half ago | (#41147549)

http://topdocumentaryfilms.com/heavy-watergate-the-war-against-cold-fusion/

And when you see how many billions have been spent on pipelines, power plants, and new revenue for governments around the world(income taxes, lease rights, gas taxes, property taxes)... You understand why they are scared of this.

http://money.cnn.com/gallery/news/economy/2012/08/27/expensive-energy-projects/1.html

Check out micromotor video (0)

Anonymous Coward | about a year and a half ago | (#41148241)

The story has a short video showing the microparticles zipping around.

Catalyst? (1)

Matt.Battey (1741550) | about a year and a half ago | (#41148869)

Hey, couldn't these be used as a catalyst to produce hydrogen for use in fuel cells and/or internal combustion engines?

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