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Hydrogen-Powered cars with Zero-Carbon-Emission?
Roland Piquepaille writes "Researchers from the Georgia Institute of Technology have a bright idea — at least at first sight. They want to create a sustainable transportation system by using hydrogen-powered cars. They would like to create an infrastructure where people could use a liquid fuel for driving while the carbon emission in their vehicles is trapped for later processing at a fueling station. 'The carbon would then be shuttled back to a processing plant where it could be transformed into liquid fuel.' Where will all this liquid carbon be stored? The researchers don't know. They suggest that it could be stored in geological formations or under the oceans."
There were already some pretty good ways of storing hydrogen for cars and the issue was just creating the hydrogen in the first place.
Not really. The Department of Energy has estimated that one would need at least a device capable of storing up to 0.6 kg of hydrogen per kg (e.g. a 100kg storage tank has 6kg of raw hydrogen in it) before hydrogen is just barely usable as a transportation fuel source. Ideally, 12% wt/wt storage is necessary to achieve the 300 miles per tank that most cars get today on gasoline. The best storage systems (circa 2004 when the report came out) topped out around 8% for liquified hydrogen tanks, but those are very difficult to use in practice because the hydrogen leaks out quickly. All other systems topped out around 4% and required either high temperature (metal hybrides) or very high pressures (700bar, approximately 10000 psi), again making them not yet ready for widespread use.
Hydrogen production is still an issue too though. Most of what we get now is a byproduct from natural gas processing, so it's still not carbon-neutral.
(Disclaimer: This topic is actually part of my master's thesis.)
I might be one of "global warming idiots" - for not knowing too much about it, but I failed to see how water is as bad as CO2 in this issue. Earth, as we know, has 3/4 of its surface covered by water, thus the atmosphere is basically saturated for water vapour, i.e., no matter how much water (liquid, vapour, ice, all forms combined) exists on this planet, the amount of water vapour in atmosphere as a whole system is almost constant as long as the climate (temperature, pressure) doesn't change dramtically.