Here is additional info on ethanol in gasoline and EPA mandated summer/winter blends: (Condensed and highlighted by me from a longer article.)
Q: does winter blend fuel lower gas mileage? What about gasahol?
A: "Apart from the pricing issue, winter-grade gasoline does yield slightly less energy than the summer blend but only by about 1.7 percent on average, according to the EPA. Ethanol's impact is far greater, dropping energy content and fuel mileage by more like 30 percent. Still, winter-blend gas imposes its minimal loss on every gallon your engine burns"
"In another fuel-related issue, the EPA approved the use of E15 ethanol, a blend of 85 percent gasoline and 15 percent ethanol, for model-year 2001 and newer cars and light trucks in June 2012, according to AAA, but few E15 gas pumps have taken to the road so far certainly not in our region. AAA said in December that "a handful" of stations in the Midwest were selling E15, but almost all gasoline sold today consists of E10, or 10 percent ethanol.
Q: Why no E15?
A: "Many reasons, according to Jeff Lenard of the National Association of Convenience Stores, which represents the businesses that sell most of our gas these days. Though EPA concluded that E15 won't harm the newer engines, the decision was controversial AAA wants E15 sales suspended pending further research, and some auto manufacturers have warned that use of E15 could void engine warranties. Ethanol is more corrosive than gasoline, and opponents say it can degrade rubber parts and other engine components.
So gas station owners have obvious liability concerns over possible engine damage, including from "misfueling" motorists using E15 in older cars, despite EPA rules for specified pump labeling."
Q: What are the auto manufacturers saying?
A: "A colleague of mine received this warning recently from her car dealer: "We would like to give warning to not use the E15 blend ethanol fuel in your Subaru. While it is approved by the EPA to be produced, it can only be used in 'Flex Fuel' vehicles [which] comprise less than 5 percent of gas vehicles on the road today. Any problems resulting from the use of the E15 blend fuels will not be covered by Subaru's warranties, and the cost will be the responsibility of the car owner."
Q: If there is such a backlash why is there a push to increase the alcohol content of gasoline?
A: "The push-back against E15 creates a significant speed bump: Federal law mandates the sale of specified amounts of ethanol for use as motor fuel each year, the volume ratcheting up every few years. Because we've generally been driving fewer miles and getting better mileage, overall motor fuel usage has declined, and without more ethanol in the mix, the minimums might not be achievable"
My comment: Can you say, "strong agribiz lobby"? Especially since we are still exporting a major part of our domestic oil production.
AAA and SEMA together can't throw 1/2 the money at congress that the agribiz lobbyists do. They have to carefully pick the smaller battles they have a chance of winning. Congressmen (and women) are not automotive enthusiasts or really care what the cost of gas is or if the fuel they are mandating is damaging vehicles. If they did they wouldn't be chauffeured around in the biggest land barge SUVs and or limos available. Have you ever seen a politician driving a Prius or smart car or heaven forbid, taking public transportation???
The thing with the ethanol "debate" is that there are a lot of people who are against it because of the impact on food prices, and the huge subsidies, not out of any concern for impact on fuel systems. I think AAA et al would have a lot of support, even from the Sierra Club.
If the drought is anything like last year, it may be a moot point. There won't be enough corn to make any ethanol.