Ethanol is highly subsidised and reliant on petroleum and natural-gas fed processes. 40% of US corn goes to provide about 10% of motor fuel as ethanol, with a net EROEI that's very close to break-even -- some studies show a net energy loss, a few a slight gain.
At the turn of the 20th century, when horses were used for local transport, about 25% of US grain production went to transport fuel supply -- as horse feed. In Europe, historically, that value was closer to 33%.
Pricing these in terms of labour equivalents without mechanisation or fossil-fuel derived fertiliser and pesticides probably gives the fairest comparison.
Scaling biofuel production to present levels of petroleum consumption is entirely nontractable.
Biodiesel costs range from $300 to $1000 /bbl. That's 3-10x petroleum at its peak prices, and 10-30x its recent price of ~$30 bbl.
As an opportunistic adjunct to fuels, biomass from waste streams and some dedicated fuels production may make sense. At present scales of fuel use, it cannot and almost certainly never will compete. We'll either have to use far less fuel, or have far fewer people. Which may happen regardless.
At the turn of the 20th century, when horses were used for local transport, about 25% of US grain production went to transport fuel supply -- as horse feed. In Europe, historically, that value was closer to 33%.
Pricing these in terms of labour equivalents without mechanisation or fossil-fuel derived fertiliser and pesticides probably gives the fairest comparison.
Scaling biofuel production to present levels of petroleum consumption is entirely nontractable.
Biodiesel costs range from $300 to $1000 /bbl. That's 3-10x petroleum at its peak prices, and 10-30x its recent price of ~$30 bbl.
As an opportunistic adjunct to fuels, biomass from waste streams and some dedicated fuels production may make sense. At present scales of fuel use, it cannot and almost certainly never will compete. We'll either have to use far less fuel, or have far fewer people. Which may happen regardless.
https://www.reddit.com/r/dredmorbius/comments/2cvap7/the_int...