$0.1 is the price of for carbon offsets. 1 Gallon gas = 20lbs CO2, and going rate for carbon offsets are $10/ton. Due to how CA cap/trade works I can't directl

$0.1 is the price of for carbon offsets. 1 Gallon gas = 20lbs CO2, and going rate for carbon offsets are $10/ton. Due to how CA cap/trade works I can't directly figure out the marginal cost difference there, though it looks greater than the market offset rate (as you note these rates depend on caps). Obviously I don't think that offset capture the total externality, but if a comparison is to be made some figure is needed. Even our 'green energy' figures don't capture their own substantial carbon footprint entirely.