Want Cheap Gas? offers the complete rationale for using biofuel and gasoline mixture to lower the cost of gas, reduce depence on foreign oil, and lower greenhouse gas emissions (GHG). E85 (85% ethanol and 15% gasoline) sells for $1.00 a gallon cheaper nationally than pure gasoline. It runs in flexible fuel cars which also use regular gasoline. For $150 a new non-FFV can be converted to a FFV.