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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."
First you say the cars are hydrogen-powered, then you say the carbon emissions will be trapped and disposed of when refuelling. Hydrogen doesn't contain carbon. Where do carbon emissions come from? This has to be the most contradictory Slashdot summary in a long time.
First, let's ignore how much energy we're throwing away in step 2 by not utilizing the full energy potential stored in the hydrocarbon molecules. Second, somehow we'll expend more energy to liberate the hydrogen and capture the carbon, both without oxidizing them. Third, we're going to tote around another 75 - 100 pounds of weight with the stored (and somehow liquefied) carbon that will be returned. Less energy potential that ever reaches the engine/fuel cell, and even more expended to refine something fairly energy dense into something that's a fair amount less energy dense.
The problem with this idea is there's too much fixation on sequestering every last bit of carbon, rather than focusing on a bigger, more important concept called energy efficiency. Work on improving that and the carbon emission reductions usually follow.
Another thing that the hydrogen/fuel cell "economy" is missing is the fact that there are virtually zero hydrogen fueling stops. The cost to put in hundreds of thousands of H2 pumps and the infrastructure to haul the liquid H2 to the corner gas station will be enormous.
Electric cars? Got a 120VAC or a 240VAC outlet? Its not that simple because 120VAC won't charge a car's batteries quickly (though its viable for overnight use.) However, adding circuits and having people standardize on a charging mechanism for cars when parked in parking lots is a lot simpler than the tanks, transportation, and specialized fuel dispensing systems needed for hydrogen. The technology for bringing electricity to every car in a parking lot does exist -- Many Alaskan shops and businesses have plugs for customers to plug in their engine heaters because at -20 (F) and below, the oil starts solidifying in the car.
I look forward to electric cars. In a lot of cities, 100% of power comes from wind and solar, so its not shifting the carbon to another source. Slow charging can be done at home, fast charging (especially with supercap batteries that can charge very quickly) can be done at the normal filling stations, so the existing gas stations won't be losing market anytime soon.
I don't look forward to a hydrogen economy, and the bugs and hassles a vastly new fuel infrastructure will bring with it. Not to mention the fact that someone has to pay the cost of sinking the H2 tanks underground in tens of thousands of gasoline stations... and that will end up being the customer.