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CNSNews.com ^ | April 10, 2012 | Elizabeth Harrington

[Flying Circus]

Their numbers don’t add up. Specific gravity of gas is between 0.71 and 0.77, or between 5.93 and 6.43lbs per gallon. 12lbs Carbon are required for every 44Lbs CO2, so for 28lbs CO2 you have to have to get 7.6lbs of carbon from gas. To get 28lbs of CO2 from 1.25gal of gas, the gas would have to be between 95% and 102% Carbon by weight. The most carbon rich hydrocarbon I can think of is Benzene (C6H6) and that is only 92% Carbon by weight. Therefore the claim that 1.25 MGal produces 28 MLbs CO2 is an impossible exaggeration.

More realistically, gas is about 83 to 85% Carbon by weight. So a gallon of gas produces roughly 18 to 20 lbs CO2.

[jeffc]

I still think the gub'mint is fudging their numbers. I don't think they're calculating things correctly, to make it worse than it really is.

I read somewhere that optimum fuel mixture is about 15/1 (15 parts air/1 part fuel). I assume that to be volume, so...about 15 gallons of air to 1 gallon of gas. How much does 15 gallons of air weigh? Not all of that is converted to CO2 (CO2 just being a waste product of the created energy), so what's left? I just don't think 15 gallons of air and 1 gallon of gas produces 28 pounds of CO2.

[Flying Circus]

You are confusing your ratios. 15:1 is not volume, it is stoichiometric. For each carbon atom in gas, you have to bring in a O2 from air to burn with it. If you don’t bring in at least that much oxygen you are running too rich, cannot burn all the fuel completely and get unburnt gas and soot out the exhaust. In volume the ratio works out to more like 6500:1.

If you look through my numbers you can see how it works out to 18-20 Lbs CO2 per gallon. Personally I think the weight of CO2 is completely irrelevant relative to the total volume of atmosphere. Our atmosphere is more than 99% N2 and O2 and only a small fraction of the remainder is CO2. As long as we have enough plants and algae eager to absorb every bit of CO2 in their reach we have nothing to worry about.