image

    FIGURE S-1 Renewable fuel volume consumption mandated by RFS2.

    NOTE: All volumes, except for volumes of biomass-based diesel, are shown in billions of gallons of ethanol-equivalent. The consumption mandate for biomass-based diesel is to be met on a biodiesel-equivalent basis.

    BOX S-1
    Definitions of Renewable Fuels in RFS2

    RFS2 divides the total renewable fuel requirement into four categories:

    Conventional biofuel that is ethanol derived from corn starch and has a life-cycle greenhouse-gas (GHG) threshold of at least 20-percent reduction in emissions compared to petroleum-based gasoline and diesel.

    image Biomass-based diesel that achieves life-cycle GHG reduction threshold of at least 50 percent.

    image Advanced biofuels that are renewable fuels other than ethanol derived from corn starch and that achieve a life-cycle GHG reduction threshold of at least 50 percent. Advanced biofuels can include cellulosic biofuels and biomass-based diesel.

    image Cellulosic biofuels derived from any cellulose, hemicellulose, or lignin from renewable biomass that achieve a life-cycle GHG reduction threshold of at least 60 percent.

    KEY FINDINGS

    FINDING: Absent major technological innovation or policy changes, the RFS2-mandated consumption of 16 billion gallons of ethanol-equivalent cellulosic biofuels is unlikely to be met in 2022.

    The United States had the capacity to produce 14.1 billion gallons of ethanol per year from corn grain and 2.7 billion gallons of biodiesel per year from soybean oil, other vegetable oils, and animal fats at the end of 2010. That year, about 13.2 billion gallons of ethanol and



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