B_H, is your vehicle a dual-fuel type?
My work Suburban came from the factory as dual-fuel, and I've heard that that is what most government-use vehicles are. (Kind of two-faced: ready to use an alternative fuel, but preach against it to keep the favor of BigOil.)
If I remember correctly (no guarantees), you are far more likely to experience problems with bio-diesel than with alcohol in cold weather, but I think there can also be a problem with alcohol separating from the gasoline, and then it produces less power. I think that's how it goes. And the kind of alcohol is important, too. Methyl alcohol separates quite easily, ethanol does, but not as badly, and butyl alcohol doesn't at all.
Pure ethanol freezes at -173°F (-114°C), and pure gasoline freezes about -150°F, but I wonder by how much a little water throws those figures off?
Sue
Alcohol fuel comes in 4 grades in the rural areas here. I have tried both E-75 and E-85 in my flex-fuel Chevy Impala this winter with good results. When I purchased the car, the technician told me that the tank should be near empty when switching fuel types to avoid confusing the onboard computer that adjusts for different octanes. The coldest weather I have left it out overnight has been 18 below zero. I have not had any trouble with long distance driving, freezing, lack of power, or starting. There is a small difference in mileage and power, but in flatland freeway driving, the power difference is imperceptable, and fuel economy is 85-90% of gasoline. The price can be as much as 90 cents a gallon less than gasoline, but more oftern it is 50 cents less. I only wish our Chevy Trailblazer had the flex fuel option too. I am seeing more Suburbans and big pickups at the E-85 pumps these days. I'll ask some of them how their mileage is.
I pay a lot for fuel because I travel for a living. I don't mind the cost as much when cutting a check to Iowa Sheik Ole Olafsonn and his wife and 6 kids for the fuel.