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."