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When articles like that have statements like this "A kilogram of hydrogen contains as much chemical energy as a gallon of gasoline" (ie some meaningless confusion of different measurments of an amount of something) you just know its a copy of some marketing departments blurb - designed specifically to make a point even if the facts don't back it up.

Its at this point that I stop reading.
 

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I'm sure than most informed people on here will find that article so annoying they wont know where to start in taking it apart as its seriously misleading throughout. No doubt the HFC fanboi's will spread the FUD but I wonder if any of them will want to drive an HFC after seeing the videos below ?

The '1kg' point ignores the inconvenient fact that in order to get the same specific energy density of a gallon of petrol, the hydrogen needs to be stored in a 5,000 PSI tank ... in a car? . . . good luck with that . . .

We've all seen the amount of FUD last year when just 2 Tesla's had bizarre accidents resulting in a gradual fire and the car subsequently informing the driver to pull over and vacate the vehicle.

So, I wonder what the media will do when a 5,000 PSI hydrogen tank explodes on bad impact leaving a crater in the road, atomising the driver in a nanosecond ?


Russian video of a truck with gas bottles exploding using only a few hundred PSI :-



Substantial damage caused by a gas bottle being used as a bomb in an empty Bahrain street:-



I can honestly say I will never own an HFC.
 

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5000psi is only about half the pressure of thw 700 Bar tank in the BMW Hydrogen 7 (ICE) FWIW.

I'm waiting to see the failure testing of specific parts of the fuel chain, car tanks, station tanks, pipelines and tanker tanks.

Hydrogen isn't as volatile as some other gaseous or liquid fuels which combust much slower than Hydrogen, comparatively, but are more explosive due to the volume of gas they create in a short space of time (which is what an explosion essentially is). Hydrogen only burns to steam - my chemistry is rusty so I can't remember whether that means it'll be less explosive. Explosive and "burns quickly" are not the same thing at all.
 

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Gasses cool as they expand and heat up under pressure.

A rupture in a pressured container is dangerous as the fracture usually opens up and the gas escapes quicker. Same sort of thing as an airplane having a rapid depression apart from not being a mile high.
 

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Some dim and distant previous lives are coming back to me. Hydrogen doesn't act as an ideal gas under expansion i.e. it heats rather than cools. Liquid Hydrogen is the most efficient (wallop per unit weight) rocket fuel, but that's not the last word in how it'll behave down here. Doesn't look good though...
 

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I wonder how this car would fare under the type of high speed crashes through a wall the Tesla Model S went through a while ago where the driver walked away without any injuries.
 

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I don't remember my physics or chemistry well enough to comment on what heats and what cools but what I do know is that it ain't safe!

The kinds of pressures involved and temperatures needed are in the scary range and if anyone was designing a replacement for petrol/diesel now I am pretty sure they would consider H2 any safer.
 

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Lol. It's basic physics. Get a bike pump and compress the gas in it. It will heat up.

Fridges work by compressing a gas, cooling it outside the cabinet then decompressing it as it passes inside the cabinet.

Also note the warnings on Co2 extinguishers not to hold the horn whilst discharging because your hands will freeze on it.

I can't belive were actually in dispute over this, it's year one physics.
 

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Let's not forget that Hydrogen is used to make electricity and it these volt that power the car rather than burning hydrogen. So it's just a type of battery when you think about it. Still a stupid idea as you still have to make and distribute the hydrogen. But on the positive side it might have a use in trucking and HGV vechicles in the long term?
 

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You would be mad to put a highly flammable product in a tin can and move it around at 70 mph:eek:

And I don't mean the wife;)
 

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Flammable less of an issue than poison if it leaks into the car. As it does not smell as a gas this requires a gas sense for warning the driver. Joy!
 

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It is hard to find "scientific research" on this topic that isn't biased one way or the other. Some of the pro hydrogen blogs I've read were insanely biased. One recent one put the cost of batteries over $2000/kWh with a 500 cycle lifetime. With numbers like that, of course batteries come out looking too expensive.


One observation. Many pro hydrogen articles say fuel cells power American manned spacecraft.


I decided to do a little research. I found that fuel cells were popular in the 1960's and '70s. The current generation of spacecraft do not use fuel cells.

I should start blogging again. The details would make a good blog post.






Mercury used silver zinc batteries.
Most of the "long range" Gemini space craft used fuel cells on-orbit with silver zinc batteries for ascent, reentry and backup. Other Gemini spacecraft were all silver zinc.

Apollo CSM Five silver-oxide zinc batteries in the command module and three fuel cells in the service module.
Apollo Lunar Module. Silver zinc batteries.

Space Shuttle Three fuel cells. Each cell is 12kW peak and 7kW continuous. 2,000 hour service life.

ISS PV charging nickel-hydrogen batteries. The batteries cycle 16 times a day and have a 6 1/2 year service life. Not sure about the Russian sections.

Spacex Dragon. PV charging Li-polymer batteries.

Boeing CST-100. Li batteries of some sort. Probably Li-cobalt

Orion MPCV Solar PV charging Li-ion batteries built by Yardley.







https://archive.org/details/nasa_techdoc_19790077942 Page 10-3 to 10-11
http://www.ibiblio.org/apollo/Documents/GeminiManualVol1.pdf
https://www.hq.nasa.gov/alsj/alsj-LMdocs.html
http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts-eps.html#sts-eps

http://www.boeing.com/assets/pdf/de...on/systems/docs/ISS Electric Power System.pdf (see the last page for a photo of the nickel hydrogen batteries.


http://www.spacex.com/news/2013/02/09/going-solar
http://www.spacex.com/sites/spacex/files/pdf/DragonLabFactSheet.pdf

http://www.google.co.uk/url?sa=t&rc...=zFg-DoMoM51AMH1_omHb-w&bvm=bv.80120444,d.d2s


Anyone read Russian? --> http://www.khrunichev.ru/main.php?id=55
 
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