Reply #4: It depends on how you make it, what you make it from, and how much you expect to get [View All]

[htuttle]

For example, ethanol can be created naturally in certain fruits and berries after they ripen (and ferment in the sun). You can't get much fuel out of that, however.

Big picture-wise, the raw energy input for ethanol (that ultimately we use for 'work') is the sun. So far, recovering that energy input is costing too much for the quantity of ethanol we need (ie., we want a lot of it). On the other hand, that same energy is easily obtainable in small quantities by digestive systems (if we eat the fuel feed stock instead of ferment it). If it's tasty, of course.

My point, rather than being merely irritating, is that it's not 'ethanol' that's inefficient. It's the way we go about making a LOT of it that's the problem.