Peak sugar!

One more commodity used to fuel our cars’ limitless needs is running out…br>
About half of Brazil’s sugar cane crop is used for domestic ethanol production, with flexfuel cars accounting for almost 50 per cent of domestic new car sales. They also represent a budding export industry, with the US, Sweden and Britain already selling the environment-friendly cars.

..So demand is skyrocketing, because of our need for energy, and oil-substitutes. An indirect sign of peak oil, if that was ever needed. And it’s happening really, really quickly…

..The private auto, the jet aircraft, and the planing heavy vessel are the ultimate worst case for fuelling, because they require high energy density (high burn rate), which is the costliest thing to achieve in a fuel. They work only by releasing very large amounts of energy very quickly and keeping up this high burn rate for extended periods. Thus they require the most grotesque conversion factors from raw (feedstock) calories in to calories out. [and the reason they do this is not only because of the physical inefficiencies of internal combustion and excessive carcass weight, but because we insist on using them for extreme time compression, i.e. extremely high speeds.]

We have traditionally got this staggering conversion factor by looting geological/evolutionary time, i.e. spending, in a scant century or two, the fossil wealth “wound up” out of biotic processes plus sunlight (heat) plus pressure plus geothermal heat plus aeons of time.

If we now try to produce this same energy density or burn rate using immediate biotic sources, we run into a little problem — a time travel problem as it were: a normal growing season doesn’t deposit that much energy in a vegetable crop. Our desired burn rate is grotesquely disproportionate to the growth rate of biotic sources, whether vegetable or animal — you couldn’t drive around carrying the amount of raw feedstock needed to produce the calories to keep the vehicle moving. So we have to invest a lot of heat/pressure (i.e. energy) to provide even a feeble approximation of the time compression we want. In other words, burn a lot of coal (or something else fairly dense) to make ethanol; and burn a lot of fossil fuel in artificial soil enrichments and fossil-powered factory farm equipment to force a higher-than-natural yield rate, to wrench as many calories per acre as we can from depleted soil. (Again trying to optimise density, not overall EROEI).

Energy Bulletin