Could someone perhaps check the rules of thumb that I use for estimating the carbon footprint of hydrocarbon fossil fuels- I'm using schoolboy chemistry theory, and possibly falling into schoolboy traps.
2 litres of LPG weigh 1 kilo 4 litres of petrol/gasoline weigh 3 kilos 6 litres of diesel fuel weigh 5 kilos
If I assume- can I?- that the above fuels are saturated hydrocarbons, propane or longer, with two hydrogen atoms for every carbon atom, then 7 kilos of fuel correspond to 6 kilos of carbon, which in turn correspond to 22 kilos of CO2.
This is a simplistic view, which doesn't take account of the production and distribution impact of road fuels, but if say, I fill up my 1980 Land Rover- whose environmental impact of manufacture ended 37 years ago- with 100 litres of LPG, I can think : 100 litres of fuel, 50 kilos of hydrocarbons, 42 kilos of carbon. I've got to deploy 42+ kilos of biochar before I can drive on with a clear conscience.
Thanks for any help.