Renewable Fuel Standard Extension Act of 2007 - Amends the Clean Air Act to redefine the term "cellulosic biomass ethanol" to mean ethanol derived from any cellulose, hemicellulose, or lignin that is derived from renewable biomass. Redefines the term "renewable fuel" to include motor vehicle fuel that is derived from renewable biomass other than ethanol derived from corn starch.
Increases the volume of renewable fuel that gasoline is required to contain for 2008-2012. Sets forth the applicable volume of renewable fuel for 2013-2016.
Revises the calculation used to determine the applicable volume of renewable fuel for 2017 and beyond by using the ratio of 18 billion gallons (currently, 7.5 billion gallons) of renewable fuels to the number of gallons of gasoline sold or introduced into commerce in 2012.