Quote:It's not so much that it's chemically hazardous or volatile - we already use a lot of things that are worse quite heavily - as there being no good way to store it with any kind of density. Putting it under pressure, like propane, makes explosions much more likely and/or dangerous, and as a liquid it's highly cryogenic - much more so than, say, LNG. Even if you do the energy density isn't great - which is why the first stage of big rockets like the Saturn V tend to end up using kerosene as fuel rather than LOH: that deep in the gravity well, the weight of the tanks affects your overall burn time more than the efficiency of the fuel. Plus, H2 is such a small molecule that it'll filter and leak through just about anything if you give it the time.
Hydrogen powered cars... I've always been under the impression that the biggest problem with them was that pure hydrogen is really dangerous. >.>
So, overall, hydrogen is cleaner than anything and stores a lot of power for its weight, but just isn't dense enough to match the power-per-volume of more conventional fuels.
Ja, -n
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