[ladydark]

When comparing ethanol with biodiesel as alternative fuels, by comparing there heat of combustion, is a lower heat of combustion more or less efficient? I know the heat of combustion of fuels is the amount of energy liberated when the substance is completely burned. So Finding the heat of combustion for both biodiesel and ethanol, allows for the measurement of how efficiently the heat of the fuel is transferred into usable heat. So doesn't that mean that a lower heat of combustion means it utilizes it's energy more?

[opti384]

I think other than the heat of combustion you should consider the number of carbon-carbon bonds together.