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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."
And where do they get the electricity to reprocess the Mg02?
From an oil- or coal-burning power plant, of course.
Or a nuke plant.
These ideas of using renewable chemical fuels is all pretty silly, because they all use electricity to renew the fuel. But electric vehicles are efficient, viable, can be made attractive and fast, and they cut out the middle-man by allowing you to plug into a supply of electricity you already access. No infrastructure cost = lowest economic barrier to entry. And it's infrastructure that we have 150+ years of experience maintaining and improving.
Eventually all of our energy will be delivered from electrical utilities, generated from coal (the oil will run out soon but we have several hundred years' worth of coal left), nuclear processes (about a thousand years' worth), and the sun (several billion years, but it's terribly inefficient so far).
Combustion Carbon will be in the form of Carbon Monoxide (CO) and/or Carbon Dioxide (CO2). We do not have technology to create solid forms of carbon (quickly enough) to be useful on a passenger vehicle. (but that would be cool)
Both of these waste carbon gases (CO2 and CO) require significant refrigeration with high compression to store them in any significant quantity and that, my friends, *Requires tremendous Energy*. The work of "sequestering" the Carbon and storing it will eat away any profits in the manufacturing of and efficiency of the vehicle and it will add complexity to an already complex piece of machinery. Not to mention there will have to be one or more pressurized vessels (think explosion, frostbite, and suffocation hazards potentials too).
Carbon Sequestering is a pipe dream (thermodynamically) but it is great for getting venture capital from those investors who have not studied and understood the principles of thermodynamics and basic organic chemistry and who also want to claim that they are investing in "green" technology. (And there may just be tax breaks for such obvious non-competitive investments like 'Sequestering' to the 'Fossil Fuels Industries'??)
"Carbon Sequestering" is really only handy (though still very efficient) if you happen to be talking about a sessile terrestrial power installation over a suitable subterranean geological Carbon gas receiving reservoir. Like this one: http://science.slashdot.org/article.pl?sid=08/02/03/1845204&from=rss (A budget increase from 1.0 Billion to 1.8 Billion proves its inefficiency alone, and that's before you consider how much more fuel is required to capture all of the HOT exhaust and cool it down to the point it could be compressed and injected into exhausted/abandoned Oil or gas 'injection' wells.
The "Oceans" basically make CaCO3 (Calcium Carbonate) out of CO2 and CO (with the help of Trillions of organisms) and it falls to the ocean floor and becomes rock eventually. This is the PRIMARY carbon "sink" on the planet. I would put more research into helping that process (oceanic Carbon capturing) and focus on Electric Cars powered by Hydrogen cells and NOT Hydrocarbons and not Hydrogen combustion engines... they are too inefficient. Carbon is simply not needed in the fuel cycle. (Unless you want fuel cells that run off of Natural Gas (Methane/Ethane AKA CH4/C2H5) or some form of Alcohol (Methanol/Ethanol AKA CH3OH/C2H5OH)).
Ultimately, using electricity to power the car's electric motor is the only truly efficient way to go (as of today)... It is only a matter of whether it is powered from a battery that is charged with electricity from the grid (preferably Nuclear and/or Hydroelectric), from an internal generator burning fuel (like modern diesel/electric Trains), and/or capacitors, solar cells, or small nuclear reactors... Burning Carbon-containing fuels (from whatever source...but note: they *WILL be from Fossil Fuels* as long as they are cheaper) is just more of the same since the invention of the combustion heat engine. It is business as usual.. Using Corn to make alcohol is a pretend market that will utterly fail without the heavy government subsidies it is seeing. (Research ADM and its lobbying efforts.)
Carbon Sequestering is really interesting, but it requires TOO MUCH energy to do.. Last time I checked, you use about 2 Watts of power to remove about 1 Watt of heat from your home/office using efficient air conditioning. What will it require in energy to remove the heat and to compress (compression releases MORE heat BYW) the exhaust of a car buring some Carbon-containing fuel? Exactly. Electric is the ONLY way to!
You make a very good point, Thank You. I do not disagree, I should have re-read the post before submitting
Hydrogen Fuel Cells are not as efficient as what I would consider to be "Efficient" either. BUT, they are more efficient than the burning any Carbon-containing fuel in order to spin a generator or to spin a drive shaft. I was thinking of Hydrogen fuel cells as being more efficient than the mechanical "heat engines", but you are absolutely right. (plus fuel cells have to have ultra-purified fuel stock and the membranes breakdown and become even less efficient, etc...
I am hopeful that the new Lithium-Silicon-Nanowire Batteries as discussed here recently will make the rechargeable storage-battery to electric motor-powered passenger vehicles efficient and practical: http://hardware.slashdot.org/article.pl?sid=08/01/16/027236
A Toyota Prius with one of these new batteries (about the same size/weight as the existing Toyota Lithium Ion battery module) would have a range of over 300 miles per recharge (about the range of a standard fuel tank's worth of gasoline and farther still if one pulled out the gas engine and added more battery capacity under the hood too).