I’ve heard that E85 has less BTU’s and gives poorer MPG’s than gas in the same vehicle? Is this true and will it figure into the CAFE standards or be given an exemption? My ‘07 Chevy Silverado is E85 capable, but I’ve never burned any.
It's a fact of chemistry and cannot be altered by any technology. Ethanol is about two-thirds as energy-dense as gasoline; in other words, if you can get a given amount of energy out of a gallon of gasoline, you would need to burn about 1.5 gallons of ethanol to release the same amount of energy. And if ethanol were unsubsidized, it would be somewhere around 10% - 30% more expensive per gallon (not per amount of energy) than gasoline, even at current prices.