fear monger ... I've been hearing these "alarms" for decades.
Minnesota is calling for 20% total/average by the year 2013. Big deal. It won't be the only fuel you could buy in MN, there are too many cars on the road that won't run it (like the vast majority of 2006 models). The air/fuel ratio would need to change even for 20%, something current cars cannot do except for flex fuel cars.
Minnesota's action is
designed to boost E-85, which GM is talking about quite a bit lately. On the other hand it's about time that bio-fuel was used big time. It'll be great for new cars.
Regarding fuel economy: E85 (15% gasoline, 85% ethanol) is only 15% worse mpg that gasoline, so a mere 20% ethanol as in Minnesota's plan wouldn't lower MPG much. Note that MN has the most E85 stations right now (208 stations) while California has none. There are only 300 E85 stations now out of 200,000 fueling stations nationwide. This is about corn-producing states in the midwest that have methanol factories. reference: Autoweek magazine april 24, 2006 page 18.