>> A fuel like Ethanol, (C2H3OH) I don't know. I don't think the mileage >> per BTU is particularly bad, but I don't know how the CO2 calculations >> would go. I'm sure the opponents who assume the worst about biofuel >> derivations would assume a very poor net-energy for ethanol, after >> energy has been invested in creating it, so they might say the CO2 >> emissions are enormous, over the whole process. >> > >Bio-fuels don't contribute ANY net gain CO2. The CO2 they produce is >absorbed by growing the plants to produce the bio-fuel. Personally I'm now >leaning towards 100% bio-diesel or straight vegetable oil. Almost exactly >the same emissions as CNG, and it's renewable. Also these are viable options >for amateurs to use to extend the range on their EVs.
Overall I am a very big fan of biofuels. I guess I was trying to spell out some shorthand for the objections that detractors might raise. In the case of ethanol (not the same thing as biodiesel), the most petty of objections have been that the fuel is net-energy-negative, meaning that some claim that more fuel is used in making it (in tractors, steam generation, fertilizer, etc.) than is produced. I think this is nonsense, although there is certainly a fair amount of fuel used. At present, petro fuels are often used in tractors and fertilizers, but as time passes maybe biofuels will be used to make food for biofuels. There are other objections such as the suitability of using agricultural land resources for fuel instead of for food, but it's a big giant debate. I like biodiesel for right here right now because at small scale levels it can amount to waste-to-energy, and is a hell of a way to get the goat of the Oil Companies. Just this past week, there has been impounding of cars in Great Britain because biodieselers were, heh, not quite paying the taxes required when they filled up. Regardless of food growth leading to CO2 use, at its simplest burning of a biofuel does result in a CO2 emissions. Yes, this is reversed when the food is grown, although I'm not sure of the exact numbers. I think it's sustainable. >Amateur vehicle conversions to propane or CNG are no longer legal because >they usually end up causing MORE pollution than normal vehicles. >
