Well, Bob is right *and* Berg is right, and so are several others. Any why are we arguing over something we can't do anything about (being a federal rule)?

The only saving grace, for us train nuts, is that ethanol is as difficult to push through a pipeline that has to also be used for other things (that is, nearly all pipelines other than natural gas) as it is to keep mixed with gas. So the stuff has to come in tank cars, usually in large blocks or unit trains, which then get offloaded at various terminals and the stuff is trucked to the distributors. Of course, practically no regular fuel distributors have spurs any more. (Somebody will probably find one in use for ethanol deliveries, but they're really rare.)

Hysterical Historical Rant - skip the rest of this if you want to keep your sanity.

EPA required oxygenate in *winter* fuel a long time ago to reduce CO emissions (not CO2) from cold starts of vehicles without feedback fuel systems (3-way catalyst), usually carbureted. The oil companies though they had died and gone to heaven, because the Very Best Oxygenate was right there: MTBE, which otherwise was a waste product they had to pay to get rid of or flare if nobody was looking. It was a great oxygenate, very stable in gasoline so it could be blended at the refinery, really cheap, etc. Nothing wrong with it ... except that it made the gas leak from every connection conceivable, and even right through the tank walls for some types of single-wall fiberglass tanks. And it was really evil when it got into the groundwater.

Took a while to figure all this out, and it'll take even longer (i.e. not yet even close in many cases) to clean it up. Then there was a panic to find a substitute oxygenate. The only one available was ethanol, which had been blended into "gasohol" in some midwest states for years (many cars delivered into those states since the 1950s were tuned to accept (though not run really well on) gasohol, so the technology isn't anything new). Back then, gasohol was cheap junk that people used when they couldn't afford real gasoline. The corn farmers rejoiced, because here was a huge new market to make them rich(er).

Problem with ethanol, besides the high price compared to MTBE, is that it's unstable in gasoline and it has an insatiable appetite for water. So if you leave a gasoline/ethanol blend alone for a while (3-4 months would do it then; probably longer with additives to keep it all together now) the ethanol and water would separate into layers or globs in the tank, and at some point your car would get a sip and die. Also, at higher concentrations (above 10-15%) conventional gaskets and hoses in the fuel system rot out from the ethanol content - you needed a race-grade fuel system and sensors and a special engine computer to allow running on up to E85 (and for a while M85 - another bad idea from ARB that thankfully came and went quickly) but again never really caught on. Brazil found this out too (used neat ethanol from sugar cane for a while): there's much lower carbon in ethanol than in gasoline, so observed gas mileage drops almost in proportion to the amount of ethanol present.

Those flex-fuel cars? Chevy Luminas using M85 would get at most 180 miles on a tank, but on regular gasoline over 300. Gas was about 2/3 the price of M85, too. Guess what everybody actually used. Some people point out that Indy cars use alcohol for fuel - sure, but they're tuned for it (neat alcohol is well over 100 octane), but unless specifically tuned for, engines produce less power. The Luminas' ECM adjusted the spark for the higher octane, so they actually did get noticeable more power on M85. And they died, quickly. With normal EPA-mandated ethanol percentages, there's no real difference in power.

And another thing: ethanol in gasoline at any measurable percentage made the gasoline leak through the plastic fuel tanks of the time and produce ROG emissions - ARB had to require different plastics for fuel tanks to fix that. And finally - that separation issue? That prevents blending it in at the refinery; it has to be trucked separately to the fuel distributors and blended there. All in all, a bad story, but at the time it was the only relatively cheap (that didn't last long) alternative for MTBE.

Eventually, CO became yesterday's news. All but one of California's former CO nonattainment areas are gone, and the last (South Coast) is now maintenance and will go away in 2027. That was done with vehicle emission controls and fleet turnover, not with ethanol. But oxygenate lives on because EPA discovered that it has a tiny beneficial effect on ozone emissions too, and summer is ozone season (big time) in CA, so we now get the ethanol in summer instead of winter. BTW, Bob's right when he says (with fewer words than mine!) that we really don't need it at all for smog control: the oil bidness worked up several blends without either MTBE or ethanol that would have been about the same pump price or less and work better. But EPA had rules requiring oxygenate and they wouldn't waive them and ARB doesn't have the power to change that.

Much Much Later, we got into the global warming mitigation game big time and derp ethanol is renewable! Well, maybe, but the farming and the refining and the transportation added up take far more fossil fuel than is available in the ethanol. It's a net loss. And it's a fuel competing with food for farm production. And California does look at the full lifecycle (effectively, well-to-wheel) for fuel-related GHGs, not just the "we have so much more efficient refineries now" thing. So corn-based ethanol still doesn't look good (unless, maybe, it's produced and refined locally so transportation cost is minimized). We just can't avoid using it thanks to Congress and EPA.

Does anybody remember when it was really proposed that California import cheap sugar cane ethanol from Brazil instead of corn from Nebraska or Iowa? It could come in tankers or huge barges. But the federal law was quickly interpreted and partially rewritten to make sure ONLY corn-based ethanol can be used in fuel.

And that's about it. Thank you very much and good night.