There are a dozen or so ethanol plants in my County, and quite a few more scattered around the state. Some of these plants have been in production for several years. With current production economies, ethanol isn't cost effective at the fuel prices we've had, so most of the production went into "gasohol" with 10 to 20 percent ethanol added to gasoline. The G10 and G20 fuels generally are available only where they're subsidized, although the "price break" from the subsidies isn't huge.

In a few localized markets, G10 has run at around 15%, plus or minus a bit, of retail fuel sales; but it's still not universally available.

The $3 (US) per gallon (US) is about the crossover point where many believe that ethanol additive fuel could be competitive without subsidies, so obviously some have been quite excited recently. I haven't heard what they're saying this week, since regular gasoline dropped back below the $3 line.

Most US manufactured gasoline vehicles manufactured in the past few years can use up to 20 percent ethanol mixes without modification. Most recent year imports are ok with it, but there are a few unexpected exceptions. Older vehicles may have problems. It's primarily a problem of exposure of elastomer seals to the ethanol, which "eats them up." There are a few metal parts used in older vehicles that are severely corroded by the mixes. Engines with fuel injection are a bit better with it than simple carbureted systems.

Conversion of older vehicles is not normally cost effective. They'll run on it with essentially no modification, but they won't run very far.

Manufacturers are working on raising the percentage of ethanol that can safely be mixed in, but they don't seem to like to talk about whether you can burn fuels that aren't widely available. A few fairly small trial fleets are running the pure stuff now; but it's unlikely that "pure ethanol" fueled vehicles will be common for quite a while.

A main advantage of using ethanol to supplement (not necessarily to fully replace) existing common fuels is that the existing distrubution systems can handle it. There are few of the other frequently touted alternate fuels that don't require developing new storage and distribution infrastructures.

John