Bioethanol From Corn Stover: A Life Cycle Assessment. Life Cycle Analysis What is it?

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1 Bioethanol From Corn Stover: A Life Cycle Assessment Cindy Riley John Sheehan Biotechnology Center for Fuels and Chemicals National Renewable Energy Laboratory A U.S. Department of Energy National Laboratory Life Cycle Analysis What is it? A comprehensive accounting of a product s flows to and from the environment Air, water and solid waste emissions Energy resources Other primary resources extracted from the environment Cradle to grave 1

2 System Boundary Corn Stover Collection Biomass Transport Ethanol Hydrolysis and Fermentation Light Duty Vehicle Production Crude Oil Production Transport Crude Transport by barge, pipeline Conversion Oil Refining to Gasoline Reformulated Gasoline Fuel Distribution Functional Unit of One Mile Traveled You know you ve arrived when you have software... NREL s 1st ethanol LCA Lotus spreadsheet Evaluation of alternative energy technologies Argonne National Laboratory life cycle spreadsheet model GREET Commercial tools Ecobalance TEAM and DEAM A variety of other commercial products 2

3 You know you ve arrived when you have standards Life Cycle Assessment and Framework (ISO 14040) Goal and scope definition (ISO 14040) Area in dashed line captured in software Inventory analysis (ISO 14041) Interpretation (ISO/FDIS 14043) Direct Applications: Development and improvement of technology Strategic planning etc. Impact assessment (ISO/FDIS 14042) Life Cycle Analysis Overall Plan Stakeholder Input Stakeholder Input Goal and Scope Collect Data Construct Model Draft Results Modify/ Update Model Final Report 3

4 Key Stakeholders Environmental groups Farmers Automakers Ethanol producers USDA EPA DOE Key Sources of Data Oak Ridge National Lab Macroeconomic modeling Collection and transport Colorado State University Natural Resources Ecology Laboratory Modeling of soil carbon and soil nutrient cycles National Renewable Energy Lab Conversion technology 4

5 Defining the Goal The intended application, the reasons for carrying out the study and the intended audience (ISO 14040) Goal as defined by stakeholders Intended application: bioethanol from corn stover to ethanol Reasons for study: begin a dialogue on the sustainability of this technology Audience: farmers, processors, regulators, policy makers, researchers and the public at large As we cross the circles inward toward toward the point at which the quadrants meet, we find ourselves in an increasingly unstable and disorienting region. The ring closest to the intersection, where most realworld problems exist, is the one in which fundamental analysis is most needed. Sustainability: Buzzword or Buzzsaw Working at the intersection of science and philosophy Environmental policy Ethics E.O. Wilson in Consilience(1998) Social Science Biology 5

6 How Do We Measure Sustainability? Absolute measures of sustainability make little sense We agreed to approach the question on a relative or directional basis Are we more or less sustainable? Probably not a single measure Qualitative, value-oriented Sustainability Measures Fossil energy avoidance Land use and biodiversity Greenhouse gas Soil sustainability Erosion, organic carbon, soil nutrients Urban air emissions Air and water toxics Solid waste Eutrophication Acidification Community rural jobs, local economy 6

7 Setting the Scope Geographic: State of Iowa Time E10, FFVs 1 st generation enzyme conversion Conventional collection Beyond 2020 Dedicated ethanol vehicle Advanced enzyme technology Novel collection options (whole plant, slurry transport) Setting the scope (cont d) Functional unit two radically different approaches One mile driven in light duty vehicle One acre of land farmed Two systems will be constructed to deal with each This dual approach comes from our agreement to focus on sustainability from two major perspectives 7

8 System With 2 Functional Units Functional Unit of One Acre Farmed Biomass Transport Ethanol Hydrolysis and Fermentation Production Transport Conversion Fuel Distribution Crude Oil Production Crude Transport by barge, pipeline Oil Refining to Gasoline Reformulated Gasoline Functional Unit of One Mile Traveled Data Collection Soil impacts GHGs, soil health Probably the most critical part of the study The Natural Resources Ecology Laboratory Developers of USDA s Century model for soil carbon sequestration These are real popular guys right now and we are excited to have them on board Stover collection and transportation Relying on ORNL/cea studies Conversion Revised corn stover process model results Fuel Use Ford vehicle data for FFVs 8

9 Seeking Input Modeling and data collection are underway now Preliminary results will be available for review in December 2000 Venues for input Let us know if you want to participate in report review Provide input via the web 9