Environmental Sustainability of Biofuel Crops Bill Chism David Widawsky Office of Policy, Economics and Innovation US Environmental Protection Agency Photos from USDA, ARS, Image Gallery

Environmental Sustainability of Biofuel Crops 2 Crop Production Generalized Diagram InputsOutputs Crop Production Physical Factors Climate and Topography Assets

Environmental Sustainability of Biofuel Crops 3 Inputs and Outputs of Biofuel Crop Production Crop Energy Food Compounds Energy - Sun - Petrochemical (fuel, fertilizer, manufacturing, etc.) Atmospheric Carbon Water Rainfall (nitrogen) Irrigation Nutrients Fertilizer Soil & Crop Residue Agric Practices Tillage Planting Crop & Cultivar Pest Control Physical Factors Climate Temperature Rainfall Soil Characteristics Topography Slope Distance to water Assets Soil Organic Matter Carbon and Minerals Water – filter & storage Wildlife Ecological Services Land Use / Consumption Air Emissions Nitrogen (NO 2 -) Carbon (tillage) Particulates Leaching & Runoff Nitrogen (NO 3 -) Phosphorus (H 2 PO 4 ) Soil Water Recharge (pos) Evaporation (neg) Crop Production Starch – corn Oil Seed – soybean Perennial Grass – Switchgrass Sugar Crop – Sugarcane Woody Biomass - Poplar Secondary Products (Animal Feed) Distillers Dry Grain Glycerol Lignin

Environmental Sustainability of Biofuel Crops 4 Starch (Corn) For Ethanol – Outputs ►low net energy; serious sustainability issues◄ Corn Production Assets Outputs Distillers Dry Grain for Animal Feed Waste to fertilizer Heat Methane Many Alternative Uses Energy, Feed, Food, Sweetener, etc. Net Energy 1.3 to 1.7 : 1 GHG Reduction 22% < gasoline Sustainability Issues Runoff & Drain Tiles Erosion N and P Pesticides Energy and GHG Reduction are Well to Wheel Optimized, CA Low Carbon Fuel Std

Environmental Sustainability of Biofuel Crops 5 Oil Seed Crop (Soybean) For Biodiesel – Outputs ►moderate net energy; sustainability issues; lower financial returns◄ Soybean Production Assets Outputs Soybean Meal for Animal Feed Waste to fertilizer Heat Methane Many Alternative Uses Energy, Feed, Food, Oil, etc. Net Energy 3.2 : 1 GHG Reduction 68% < diesel Sustainability Issues Runoff & Drain Tiles Erosion Pesticides Energy and GHG Reduction are Well to Wheel Optimized

Environmental Sustainability of Biofuel Crops 6 Cellulosic Ethanol (Switchgrass) – Outputs ►higher net energy; sustainability advantages; technical/financial barriers◄ Switchgrass Production Assets Outputs Alternative Uses Less Marketable CRP, Wildlife Habitat Net Energy 4.4 to 6.1 : 1 GHG Reduction 91% < gasoline Sustainability Issues ☼ Lowest Runoff ☼ Lowest Erosion ☼ Low Fertilizer Use (N and P) ☼ Lowest pesticide Use Energy and GHG Reduction are Well to Wheel Optimized Develop New Biofuel Production System – acid or enzyme?

Environmental Sustainability of Biofuel Crops 7 Changing Crop Rotations ► changing rotation can increase runoff and reduce average yields◄ Corn Sustainability Issues (Minn.) NO 3 -N in runoff = 45.5 lb/acre Drain tile flow = 3.1 t water/acre 2 Year Crop Rotation 18% higher soybean yield 12% higher corn yield 2 Year Continuous Corn 12% lower corn yield Sustainability Issues (Minn.) NO 3 -N in runoff = 40 lb/acre Drain tile flow = 2 t water/acre Soybean Fertilization (U.S.) N = 15 % at 24 lb/acre P = 24 % at 48 lb/acre Corn Fertilization (U.S.) N = 97 % at 131 lb/acre P = 81 % at 57 lb/acre Soybean Corn Corn Fertilization (U.S.) N = 97 % at 131 lb/acre P = 81 % at 57 lb/acre

Environmental Sustainability of Biofuel Crops 8 Environmental Impact of Converting 14 million acres of soybean to corn Source: L. Marshall The Thirst For Corn. WRI Change in Runoff (%) Nitrogen5 million tons Phosphorus0.5 million tons Sediment1900 million tons Tons of Runoff

Environmental Sustainability of Biofuel Crops 9 Conversion System Affects Sustainability of Biomass Production Influence of Conversion Platforms on Biomass Production  Single crop systems  “Omnivorous” systems  Timing of biomass utilization  Biomass storage (quality, quantity) All of these can affect:  Water, air, soil effects  Wildlife habitat  Other ecological services

Environmental Sustainability of Biofuel Crops 10 Sustainability Characteristics* of Mitigation Options * Other categories could be added: nitrous oxides, soil carbon, wildlife, etc.

Environmental Sustainability of Biofuel Crops 11 Research Information Gaps Life Cycle Analysis – Agricultural Inputs  Accounting methods  Values of Secondary Products  Comparison Between Single-year and Multi-year Crops Impact of Biofuel Processing Method – “omnivorous” processing system versus crop specific system Biofuel “Green” Index – Well-to-Crop Rating System  Develop crop sustainability data  Methods for comparing different models Sustainability - Land, Crop Residues, and Water * Land Use Change * Crop Production Practices * * Federal Biofuels Posture Plan Workshop Feedstock Session Notes