Breakthrough in hydrogen fuel cells: Chemists develop way to safely store, extract hydrogen

Love breakthroughs!

Another breakthrough using a rare and expensive catalyst. Ruthenium isn't ever going to be cheap enough to use in cars unless its in microgram quantities. Furthermore, how stable is the catalyst? Looking at that structure I see a lot of ways that water or sunlight/heat etc. would degrade it.

"Hydrogen makes a great fuel because of it can easily be converted to electricity in a fuel cell."

At high cost and low efficiency.

yes, help, Jesus!

In a vehicle with a tank full of hydrogen, "if you got into a wreck, you'd have a problem,"

I hate this argument, as if gasoline isn't just as dangerous or even more so. hydrogen boils away and up. Gasoline vapors are heavier than air, and just pool up waiting to explode.

There are a lot of good arguments against hydrogen (see capitalismPrevails) but safety really isn't one of them.

I liked the small aircraft comment. That means lots of power in a light weight package. What I need:
1. Electric engine about 100 to 400 HP.
2. Fuel cells to make the HP.
3. Tanks to hold the solids.
4. Machinery to push the H2 bearing solid into the reforming hardware.
5. A second tank to hold the used fuel carrier.
6. Very safe control equipment that I can use in flight.

I am not convinced!

4.6% system weight equals 1532 Wh/kg in energy density, and ~760 Wh/kg after the fuel cell.

Seven times better than batteries, but I seem to recall that this system cannot be stopped after the process is started. Once it starts bubbling it won't stop.

Gasoline still has a practical energy density of roughly 3500 Wh/kg into mechanical energy at the engine shaft.

I have hopes for "H2 on demand" systems.Take Zn or Mg for example.The pure metal when oxidized with hot water yields pure H2 for powering your fuel cell.The oxidized metal can then be reduced again to elemental Zn or Mg.Refuelling your car would be simply a matter of exchanging the spent oxide for the pure metal.There are plans to do the reduction with a solar powered furnace.See: http://solar.web....EE08.pdf

Ruthenium is one of the rarest and most expensive elements on the Earth. Its annual production is only about 12 tonnes worldwide, whereas the gold production nears 2,500 tonnes per year. IMO it speaks for itself about practical significance of this "breakthrough". The true breakthrough in energy technologies is the cold fusion technology, developed by now with Foccardi and Rossi. It will make the whole hydrogen research obsolete.

I hate this argument, as if gasoline isn't just as dangerous or even more so. hydrogen boils away and up. Gasoline vapors are heavier than air, and just pool up waiting to explode.

It isn't. Gasoline quickly builds up to concentrations where it won't really explode rather than flame up, and it has a much higher ignition energy. On a leak, hydrogen probably will explode rather than not, because it has a particularily low ignition energy.

It doesn't matter that it floats up, because there's a constant stream of it coming from the leak, and it diffuses around quickly. Because hydrogen is explosive over a broad range of concentrations, and it spreads fast, it makes a thermobaric bomb effect of sorts. You get a big diffuse cloud of it that then goes pop all at once.

It's especially nasty if there's any sort of ceiling, like a tunnel or an overpass where the gas can be trapped.

Parsec and Callippo are 100% correct that Ruthenium is ridiculously uneconomical to use as a real-world catalyst in automobiles. It is so rare that there simply isn't enough of it on the planet for the auto industry.

This system is not a "break-through", and never be until they can demonstrate it with common and affordable materials.

Meta-metals, that's the way.

So sick of over hyped green technologies. Theres always a catch, in this case the Ruthenium.
Since CAGW is more a faith based thing anyway nowdays (essp since Kauffman et al 2011) perhaps the editors could stop over selling any vuagely green thing they spot?
Its getting lame.

@fmfbrestel

Can't compare liquid gasoline to super compressed hydrogen tanks. Just the sudden release of hydrogen would wreck havoc; ever see myth busters with the hot water tank that explodes through a whole house? I haven't even gotten to it exploding yet. Once it has already wrecked havoc, it would then mix with large volume of air in a split second which would amplify the explosion should it be lit; the same thing cannot be said for gasoline in liquid state which doesn't explode to its full potential because not enough oxygen during explosion. A transport who's trailer is full of gasoline is much safer than a transport whose trailer is only 1/4 full. Apple and Oranges.

ever see myth busters with the hot water tank that explodes through a whole house?

Yes, that was quite impressive. They also did an episode where they actually shot rifle rounds directly into a car's fuel tank, filled with gasoline. Contrary to Hollywood physics, nothing happened, except a fuel leak. Same deal when they repeatedly tried to cause an explosion by throwing cars of a cliff. Nothin'. In fact, they had to go to ridiculous lengths to get any kind combustion to take place.

Are hydrogen tanks any more dangerous than the CNG and LPG tanks already used in cars?

In a vehicle with a tank full of hydrogen, "if you got into a wreck, you'd have a problem,"

I hate this argument, as if gasoline isn't just as dangerous or even more so. hydrogen boils away and up. Gasoline vapors are heavier than air, and just pool up waiting to explode.

There are a lot of good arguments against hydrogen (see capitalismPrevails) but safety really isn't one of them.

You might hate this argument, but it's a good one. Hydrogen gas has to be stored at very high pressures in order to get near the energy density of gasoline. You are one of the few who doesn't recognize the danger is higher with hydrogen than with gasoline.

yes, help, Jesus!

...and the god squad has what to do with scientific breakthroughs?...

What's the other, non-H2, product(s) of the reaction?

Maybe these myths about hydrogen (more dangerous, more expensive per unit energy at the wheel) will die someday when people start looking at the facts:

http://www.pbs.or...yths.htm

Anyone who has ever seen a pressurized containment breached knows that it doesn't explode into a million pieces but breaks at one point (mostly at the rated break point)

Or simply look at the pictures of what happens when you breach a gas tank vs. a hydrogen tank.

http://www.cleanc...ety.html

Or simply look at the pictures of what happens when you breach a gas tank vs. a hydrogen tank.

http://www.cleanc...ety.html

That test clearly amounts to lying.

Spark plugs were installed outside both vehicles to ignite a leaking hydrogen tank and a leaking gasoline line.

Sure. If you light a fire underneath a car, the car will burn. If you vent the gas out of a hole at the top of the car so it can escape safely above the vehicle, and you don't let it diffuse around before you ignite it, then yes, it will just produce a nice vertical flame.

And there's a gross mis-interpretation of the chart they provide. The lower flammability limit combined with high diffusion rates just means that the fuel spreads easily, and can be ignited when diluted.

If you want to see what it would look like if the hydrogen had mixed with the air inside the car before igniting, this is roughly what it would have looked like:

http://www.youtub...Bg087hW0

Except scaled up to the volume of the car. You wouldn't have many unbroken windows in the neighborhood.

One video is sourced to DOE research. (Antialias)
Second is a backyard kids prank. (Eikka)
Not to hard to figure which is more applicable.

That test clearly amounts to lying. (Eikka)

Twisted logic from Eikka - yet another misinformed miscreant.

http://www.cleanc...ngle.png

If you take that flammability triangle, guess what's the most dangerous fuel according to it?

A stick of wood.

It doesn't float up in the air, it doesn't diffuse around, and no matter how much air you have in the same space with the stick, it will still ignite.

The only niggle is, that it's much harder to ignite a stick of wood than gasoline, which is much harder to ignite than methane, which is harder to ignite than hydrogen.

The reason:

"Although the autoignition temperature of hydrogen is higher than those for most hydrocarbons, hydrogen's lower ignition energy makes the ignition of hydrogenair mixtures more likely. The minimum energy for spark ignition at atmospheric pressure is about 0.02 millijoules."

One video is sourced to DOE research. (Antialias)

I call them liars. The flame is clearly coming out of a hole on the trunk lid. We can't even see if there is a lid.

It looks exactly like a torch flame coming out of a nozzle.

In fact, if you follow the source link, it leads you to a document from the university of Miami who conducted the test, that explains that the flame is coming out of a safety release valve and is unobstructed by anything.

That amounts to a real accident as much as an oily rag burning next to the gasoline vehicle.

The only niggle is, that it's much harder to ignite a stick of wood than gasoline,

Ignition is ignition: gasoline vapors will not be ignited as easily as hydrogen vapors but the type of ignition sources around after an accident (sparkplugs etc.) is enough to ignite either.

The difference is: if you don't get IMMEDIATE ignition after an accident with a breached hydrogen tank then you won't get one at all because the tank will be empty (and the gas gone upwards) long before anyone is on the scene with another source that could cause ignition. For gasoline? Well, the vapors can stay where they are more or less indefinitely.

In some cases the auto-ignition temperature of wood can be lower than gasoline.

http://www.engine...171.html

.. and in any case the high intensity combustion seems to be of the materials inside the vehicle. Hydrogen combusts quickly and probably does not transfer enough heat to other materials to initiate combustion.

In any case Eikka, you are talking out your arse because you are just selectively choosing data to support you feeble argument without considering alternatives.

Ignition is ignition: gasoline vapors will not be ignited as easily as hydrogen vapors but the type of ignition sources around after an accident (sparkplugs etc.) is enough to ignite either.

How does a spark plug inside the car's cylinder ignite leaking gasoline outside of the engine? Gasoline fires are actually somewhat rare with vehicle crashes, because gas doesn't go around all that much.

The difference is: if you don't get IMMEDIATE ignition after an accident with a breached hydrogen tank then you won't get one at all because the tank will be empty (and the gas gone upwards)

100 seconds is a long time to find a spark somewhere, considering that you have a cloud of hydrogen in and around the vehicle. If your gas escapes immediately, that amounts to an "explosion" in its own right.

In some cases the auto-ignition temperature of wood can be lower than gasoline.

Temperature doesn't enter the question at all. The question was about ignition energy. These are two different things.

Hydrogen has a relatively high auto-ignition temperature - about 500 C, but it still has an extremely low ignition energy, which means that a small static spark will ignite hydrogen where gasoline, or wood would not ignite.

In any case Eikka, you are talking out your arse because you are just selectively choosing data to support you feeble argument without considering alternatives.

Where exactly did I do that?

The "DOE" example was bunk, because it considered the best case scenario where the hydrogen tank leaked out through its safety release valve straight up in the air, with ignition source present right at the nozzle so the gas doesn't get to mix with air before ignition and thus burns with a nice tall and harmless torch flame.

What happens when you put that same car upside down in a ditch, let it sit there for half a minute and then ignite it?

A backyard kids experiment on YouTube and your reasoning, together trump a DOE validated test?

To be calling people liars is a sign of an intolerant fool.

A backyard kids experiment on YouTube and your reasoning, together trump a DOE validated test?

To be calling people liars is a sign of an intolerant fool.

Put simply: yes.

What you are doing is an appeal to authority without considering that the authority might be wrong or misguided, or that the information is mispresented by others (cleancaroptions.com) to be something that it's not.

The video is made by Mr. Swain of the university of Miami, and the interpretation of it is done by the website, which sources things like the triangle chart of flammability safety from "Ford hydrogen safety report".

So, you have third and fourth and fifth parties taking a few pictures out of context and making bold claims under the authority of the DOE. Doesn't look very convincing to me.

What happens when you put that same car upside down in a ditch, let it sit there for half a minute and then ignite it?

Nothing. Either all the hydrogen will be gone by then or there is no leak.

And it's also not plausible to have an ignition source enter the scenario half a minute after an accident. Either it happens right away during the accident or when help arrives minutes later.

The difference is: if you don't get IMMEDIATE ignition after an accident with a breached hydrogen tank then you won't get one at all because the tank will be empty (and the gas gone upwards) long before anyone is on the scene with another source that could cause ignition. For gasoline? Well, the vapors can stay where they are more or less indefinitely.

... and you refute this with 100 seconds, in a tunnel, upside down vehicles, burning oily rags etc. Grasping at straws?

And the "backyard kid experiment" is a demonstration that you can easily pull at home to see what happens when you do mix hydrogen with air prior to ignition.

It produces a violent explosion. Much more so than gasoline.

You don't have to believe a youtube video because the experiment is trivially repeated at home. That procedure is called peer reviewing.

Nothing. Either all the hydrogen will be gone by then or there is no leak.

And it's also not plausible to have an ignition source enter the scenario half a minute after an accident. Either it happens right away during the accident or when help arrives minutes later.

Or, there is an ignition source that takes time to develop, such as a short circuited battery, or the motion of the passengers shuffling about and making static electricity.

As presented in the source, the safety release was designed to empty the tank over 100 seconds. A smaller leak is possible. There is plenty of time for a delayed ignition.

And, what if the ignition does happen immediately and you get a 100 second 2 megawatt flame blowing from underneath the overturned car?

The more dangerous scenario is, if the hydrogen powered car is already on flames before the tank vents the hydrogen.

A gasoline powered car would add to the flames, but not explode. A sudden release of hydrogen on the other hand would produce the hollywood effect car explosion.

And, what if the ignition does happen immediately and you get a 100 second 2 megawatt flame blowing from underneath the overturned car?

Same chance of winning the lottery I guess. Have you got more very specific low probability situations that assist your argument? I hope so because i'm starting to have a good laugh. Thanks.

The more dangerous scenario is, if the hydrogen powered car is already on flames before the tank vents the hydrogen.

Pure Hollywood fantasy indeed. Can you find a YouTube video?

Same chance of winning the lottery I guess. Have you got more very specific low probability situations that assist your argument? I hope so because i'm starting to have a good laugh. Thanks.

There's over 300,000 vehicle fires in the US every year.
(http://www.nfpa.o...cle.pdf)

2/3 of the fires were caused by mechanical or electrical faults. 1/5 were caused by "Part failures, leaks or breaks". 1/10 were caused by the engine backfiring.

Collisions and overturns caused 2% of the vehicle fires. That amounts to over 6000 fires of overturned cars every year.

As presented in the source, the safety release was designed to empty the tank over 100 seconds.

If you check the source you'll find another picture ofa totalled car where the tank didn't spring a leak. It seems these suckers are very sturdy and the chances of something like that happening (i.e. a rupture that does not happen at the predesigned breaking point) is very small

Theres gas cannisters all over the place. Whole cities got hydrogen gas (town gas, which is about 50% hydrogen) - and they didn't spontaneously blow up all the time then and those cannisters don't blow up all the time now.

Yes. Hydrogen CAN blow up. But we really need to consider how likely that scnario is. It's about as likely as a car driving off the road and bursting into flames on the way down (which only ever happens in the movies)

How many resulted in catastrophic ruptures of the fuel tank and exploded? How many would have ruptured a hydrogen pressure vessel container without causing the safety valve to operate? Its all good fun but you are searching for a tiny percentage of situations to support your general argument. Your persistence is admirable even if hilarious.

How many resulted in catastrophic ruptures of the fuel tank and exploded?

Probably none, because gasoline doesn't explode like that. It's stored in an unpressurized tank with vent holes in it, so it cannot rupture catastrophically due to a fire.

The whole problem is, that gasoline, even in fire, does not burn all at once even when it escapes the fuel tank.

Hydrogen does.

(town gas, which is about 50% hydrogen)

Actually, town gas was more like to 20% carbon monoxide, 20% hydrogen, 10% methane and 50% nitrogen. The reason being that the carbon in the gas makes the flame visible. A hydrogen-nitrogen flame would not produce light, so they tried to increase the proportion of hydrocarbons over hydrogen by gasifying bituminous coals.

Yes. Hydrogen CAN blow up. But we really need to consider how likely that scnario is. It's about as likely as a car driving off the road and bursting into flames on the way down (which only ever happens in the movies)

1) the hydrogen tank is not supposed to leak
2) 2/3 of vehicle fires are caused by something else than fuel leaks

You would mostly get fires where you have an intact hydrogen tank sitting in an already burning car, which presents a problem because unless the fire is put out quickly, you have a massive venting of fire just waiting to happen.

[qThere's over 300,000 vehicle fires in the US every year.
(http://www.nfpa.o...cle.pdf)

2/3 of the fires were caused by mechanical or electrical faults. 1/5 were caused by "Part failures, leaks or breaks". 1/10 were caused by the engine backfiring.

Collisions and overturns caused 2% of the vehicle fires. That amounts to over 6000 fires of overturned cars every year.



The majority of the figures you've quoted, including electrical fires can be avoided by properly maintaining the vehicle.

The same applies to turn-overs as fuel systems tend to be well shielded from impacts as a matter of design requirement so, unless there is a leak prior, the chances of a fire in this scenario are slim.

In the UK we have to have an annual vehicle check which is very strict and highlights any faults that could cause these problems. Any faults and the vehicle cannot be used until repaired. Is it the same for the USA?

Theres gas cannisters all over the place. Whole cities got hydrogen gas (town gas, which is about 50% hydrogen) - and they didn't spontaneously blow up all the time then and those cannisters don't blow up all the time now.

The gasses used have limited explosive concentrations, typically between 6-8% in air, whereas hydrogen has 4-74%.

It's with some difficulty that you'd get a gas explosion out of e.g. a propane tank, because you either get too little or too much gas and it won't pop, and if it manages to do so, the burning velocity is 8 times less than with hydrogen, so the explosion is less violent.

Still, gas explosions are a problem. For example:
http://en.wikiped...d_States

Not all of them are gas pipeline accidents, but a great many are, and there are a lot of them.

Anyone remember the experiments at U BC where an RCMP sniper was tasked with trying to make a full hydrogen fuel tank explode? He couldn't do it. After several rounds with a .30 cal rifle, the tank's carbon fibers just sort of gave out over a large area and released the gas, which simply floated away without doing any damage or igniting.

These yahoos trying to scare people into fear of hydrogen fuel are either the ultimate Ludites or heavily invested in the petroleum industry. No doubt when automobiles were first introduced, some like them mongered all sorts of fears about the relative dangers of gasoline versus hay.

In the UK we have to have an annual vehicle check which is very strict and highlights any faults that could cause these problems. Any faults and the vehicle cannot be used until repaired. Is it the same for the USA?

http://webarchive....gov.uk/ /http://www.communities.gov.uk/pub/894/FireStatisticsUnitedKingdom2003PDF1724Kb_id1124894.pdf

About 2 out of every thousand cars in the UK are burned every year. Not so much because of accidents or ill maintenance, but because of arson.

These yahoos trying to scare people into fear of hydrogen fuel are either the ultimate Ludites or heavily invested in the petroleum industry.

Or simply advocates of more sensible fuels.

The hydrogen economy is the large car manufacturers' excuse for not doing anything about the situation. They can always point at it and go "Look, we're making progress, but it's not ready yet. In the mean while, buy this gasoline hybrid."

Of course the topic is moot if you can provide a safe container for hydrogen, which is what this article is about. Too bad it needs some of the most rare and precious materials there are, rendering it infeasible.

The gasses used have limited explosive concentrations, typically between 6-8% in air, whereas hydrogen has 4-74%.

There's a hydrogen being producd for all sorts of things (and it's also transported in pressurized cannisters.
From the link I posted earlier:
"In 2006, at least 7.2 billion kilograms of hydrogen was produced, primarily from oil and natural gas"

Hydrogen cannisters are being transported by truck.
Last time I heard of a hydrogen explosion due to one of those cannisters being crushed or a pipeline springing a leak and catching fire was....erm...can't really say that I remember ANY news item to that effect.

No doubt when automobiles were first introduced, some like them mongered all sorts of fears about the relative dangers of gasoline versus hay.

Interestingly enough, the biggest propaganda battle was between external combustion engines (steam cars) and internal combustion engines. The opposition calling the other an "internal explosion engine", and produced short films about car engines randomly exploding.

As for gasoline versus hay, everybody was pretty happy about getting rid of all the horse s**t.

There's a hydrogen being producd for all sorts of things (and it's also transported in pressurized cannisters.
From the link I posted earlier:
"In 2006, at least 7.2 billion kilograms of hydrogen was produced, primarily from oil and natural gas"

The vast majority of that hydrogen is being produced on-site from natural gas, for the synthesis of ammonia for the production of nitrogen fertilizers.

Hydrogen cannisters are being transported by truck.
Last time I heard of a hydrogen explosion due to one of those cannisters being crushed or a pipeline springing a leak and catching fire was....erm...can't really say that I remember ANY news item to that effect.

Well, here's one from a couple years back:
http://www.powerm...857.html

Accompanied with the usual "Hydrogen is not dangerous" propaganda.

Other stories:
http://www.13wham...f3Q.cspx

http://thegazette...-arnold/

And here's a site that collects hydrogen related incidents.

http://www.h2inci...mp;val=5

OK...so we had all of 5 accidents in 2011 related to hydrogen - one of which caused two fatalities (and THAT equipment hadn't been inspected in 10 years!)

To get a roadside accident you have to go back to 2009 (cylinders fall off trucks, break and ignite. 3 separate incidents - no injuries at any of them)

To get a mishap with a truck that caused injuries you have to go back to 2007 (frostbite - not explosion)

Sounds like a safe technology to me.

Just out of curiosity... Why can't they bind the hydrogen with oxygen?

Ruthenium is not cheap.
Ammonia is, but borane is not, and both require *energy* to produce.
What is the energy output of the hydrogen produced as a fraction of the energy required to create the raw materials?

For farmerpat42: The 'by-product' is a BH-NH monomer that readily reacts to make borazine - (BH)3(NH)3 - en.wikipedia.org/wiki/Borazine
If the borazine comes in contact with water it will react to make ammonia and boric acid - and a little more hydrogen.
en.wikipedia.org/wiki/Boric_acid#Toxicology

To get a roadside accident you have to go back to 2009 (cylinders fall off trucks, break and ignite. 3 separate incidents - no injuries at any of them)

To get a mishap with a truck that caused injuries you have to go back to 2007 (frostbite - not explosion)

If hydrogen fueled cars become the norm, the number of hydrogen tanks on the road would be orders of magnitude higher than they are now (simply trucks transporting hydrogen around).

I don't know if comparing industrial accidents and hydrogen transport trucks is a way to address hydrogen hazards in cars. That's like using refinery accidents and gas transport trucks as examples of gasoline safety in cars.

The failure modes are too different for a good comparison. The debate requires a cost and hazards analysis for various tank designs that factors in both risk and consequence of the various failure modes for these tanks.

For example, what's the risk and consequence of a tank rupturing "properly" with the car on its side?

Anyone who has ever seen a pressurized containment breached knows that it doesn't explode into a million pieces but breaks at one point (mostly at the rated break point)

From the following link:

BLEVE: Boiling liquid expanding vapor explosion.
This involves a pressurized vessel containing a liquid or pressurized gas, when subjected to high heat or fire, can explode VIOLENTLY sending extremely large amounts of fire and heat into the surrounding area. The tank is often broken into several small fragments causing shrapnel to fly about in the surrounding area.

http://www.cleanm...555.html

Notice the final few pictures. The tank failed to breach at the valve, which is the designed failure point. Granted, this fire didn't start with the tank, but you have to designe a hydrogen vehicle to be safe in these types of situations.

My former grandfather-in-law lost his car at an American Football game when I lived in Kansas City. Someone several cars down pushed a small barbecue grill under their car when they were done using it. A whole row of cars went up. I wonder which would be worse; hydrogen or gasoline? I'm really not sure. I guess it depends on how you design the hydrogen storage system.

I've seen it noted elsewhere that the above methode for storing hydrogen is chemically parallel to the method for making stable dynamite. Anybody with more chimstry knowledge than me know whether that's true or not?

BLEVE: Boiling liquid expanding vapor explosion.
This involves a pressurized vessel containing a liquid or pressurized gas,

It's important to note that a BLEVE could only occur in a tank with liquid in it, not with just a pressurized gas as is mentioned in the quote. It's an important distinction as much of the explosive force of a BLEVE is due to the rapid phase change from liquid to gas phase once the container is breached and the pressure quickly drops.

While BLEVEs are quite dangerous, they'd only be a concern in hydrogen storage systems where hydrogen is stored as a liquid.

While BLEVEs are quite dangerous, they'd only be a concern in hydrogen storage systems where hydrogen is stored as a liquid.

Yeah, true. A gasoline tank with a faulty vent can do it too.

Just out of curiosity... Why can't they bind the hydrogen with oxygen?

Because that would make water (H20...you know?)

And that releases all the energy stored, because that is precisely the reaction you use to extract the energy and move your car with.

but you have to designe a hydrogen vehicle to be safe in these types of situations.

And how often does that happen?

I mean, yeah: you can design your tank to be earthquake, nuclear explosion and black hole proof - but is that sensible? If in 99.9% of cases the cap burst at the failure point then that is good enough.

Because that would make water (H20...you know?)

Duh! That was the point.

Duh! That was the point.

Yes. But what good would that be? You put the energy IN there by dissociating water and storing the hydrogen. And you RELEASE energy by combining hydrogen and oxygen into water.

If you stored the hydrogen by associating it with oxygen then you'd be basically filling your tank with water. What do you expect to do with a tank full of water? There's no energy in there.

And how often does that happen?

I mean, yeah: you can design your tank to be earthquake, nuclear explosion and black hole proof - but is that sensible? If in 99.9% of cases the cap burst at the failure point then that is good enough

Yeah, exactly. It's up to government regulations. Driving down the freeway is dangerous too, but it's legal. Current hazmat laws probably need to be adapted before hydrogen can become mainstream. Government is soooooo slow compared to science.

You realize that Ricochet is agreeing with you, but trying to be funny with sacarsasm, right? He was just joking. He obviously gets it. I'll give you a 5/5 for arguing with yourself though. ;) Just kidding, but it WAS funny.

Hopefully you are both laughing WITH me. Cheers, have a drink.

Well, we could say that I was referring to this:
http://www.rexres...zius.htm

However, I was actually thinking of the little model car that MIT has that splits the H and O from water and runs off the gases.

When I was a kid I used to make hydrogen and put different ratios of hydrogen and air in a test tube under water and ignight it using an eletrical spark and what I found is that only at a ratio of two parts hydrogen and one part air did the test tube launch out of the water (fun) and all other ratios produced a weak thump ,slow flame or no ignition so in an accident like the hindenberg burning at some rate would be expected and an explosion unlikely.

Duh! That was the point.

Yes. But what good would that be? You put the energy IN there by dissociating water and storing the hydrogen. And you RELEASE energy by combining hydrogen and oxygen into water.

If you stored the hydrogen by associating it with oxygen then you'd be basically filling your tank with water. What do you expect to do with a tank full of water? There's no energy in there.

There's a LOT of energy to be got from H2O .
All you need is a little magnesium ..

There's a LOT of energy to be got from H2O .
All you need is a little magnesium ..

Yes,that is why H2 on demand does an end run around hydrogen storage issues.You only produce what is immediately needed.See: http://www.thenor...ic_cars/

Personally, I feel the primary source of power for electric cars should be solar, with the battery as the backup. Even on overcast days, there's usually plenty of UV light available to power solar cells, and with the recent advances in solar energy collection, it's a much more viable means to power the car. So, I propose that the cars use a 3-source power system:
Solar 1st, then rechargable battery, then hydrogen cell.

Personally, I feel the primary source of power for electric cars should be solar,

Do the math. The incident power upon the entire surface area of is WAY too small to power a regular car (even if we had 100% efficient solar power cells, at midday, at the equator, and wih a perfectly clear sky).

Unless we all consent to drive cars like the ones in the solar challenge that's a no-go.

Personally, I feel the primary source of power for electric cars should be solar,

Do the math. The incident power upon the entire surface area of is WAY too small to power a regular car (even if we had 100% efficient solar power cells, at midday, at the equator, and wih a perfectly clear sky).

Unless we all consent to drive cars like the ones in the solar challenge that's a no-go.

Solar charged batteries might supply some of the power for auto electronics,but the surface area isn't sufficient to provide enough energy to propel the car.

Personally, I feel the primary source of power for electric cars should be solar,

Do the math. The incident power upon the entire surface area of is WAY too small to power a regular car (even if we had 100% efficient solar power cells, at midday, at the equator, and wih a perfectly clear sky).

Unless we all consent to drive cars like the ones in the solar challenge that's a no-go.

Are you also taking into account the 100x solar collection that nanotubes has been shown to provide?
http://www.physor...475.html

You're beating a dead horse,dude.The sun only deposits a certain maximum energy per square foot.No technology is going to improve that.Solar power depends on lots of collection area,so significant power can only be produced for stationary applications.

Are you also taking into account the 100x solar collection that nanotubes has been shown to provide?

Solar constant is 800W per square meter in northern latitudes (noon, cloudless sky). No matter how good your technology is: You'll never collect more than that.

A car has a surface area of maybe 4 square meters. At 40% efficiencey (best solar cells to date - and very expensive) you get 1,28kW (and remember: this is under optimal weather/daylight conditions...at any other time it's much less).
With that kind of power you can run the heater in your car - but that's about it.