November 2000 • NREL/TP-580-28705 Environmental Life Cycle Implications of Using Bagasse- Derived Ethanol as a Gasoline Oxygenate in Mumbai (Bombay) Kiran L. Kadam Prepared for the National Energy Technology Laboratory Pittsburgh, Pennsylvania, USA and USAID, New Delhi, India National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute • Battelle • Bechtel Contract No. DE-AC36-99-GO10337 November 2000 • NREL/TP-580-28705 Environmental Life Cycle Implications of Using Bagasse- Derived Ethanol as a Gasoline Oxygenate in Mumbai (Bombay) Kiran L. Kadam Prepared for the National Energy Technology Laboratory Pittsburgh, Pennsylvania, USA and USAID, New Delhi, India Prepared under Task No. WG88.0101 National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401-3393 NREL is a U.S. Department of Energy Laboratory Operated by Midwest Research Institute • Battelle • Bechtel Contract No. DE-AC36-99-GO10337 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. 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L. Kadam iii 6.5 Summary of Scoping Decisions and Approaches ________________________________ 20 7 Life Cycle Modeling ______________________________________________________ 21 7.1 LCA Software_____________________________________________________________ 21 7.2 General Bagasse Data ______________________________________________________ 21 7.3 Bagasse Burning___________________________________________________________ 25 7.4 Ethanol Production ________________________________________________________ 25 7.4.1 Enzymatic Process ______________________________________________________________ 26 7.4.2 Two-Stage Dilute Acid Process ____________________________________________________ 28 7.4.3 Data Summary for Bagasse-to-Ethanol Processes ______________________________________ 29 7.5 Sulfuric Acid Production____________________________________________________ 29 7.6 Ammonia_________________________________________________________________ 30 7.7 Lime_____________________________________________________________________ 31 7.8 Electricity Production ______________________________________________________ 31 7.9 Steam Production__________________________________________________________ 31 7.10 Gasoline System ___________________________________________________________ 32 7.11 Gasoline and E10 Fuel Combustion ___________________________________________ 32 7.11.1 Tailpipe Emissions ______________________________________________________________ 32 7.11.2 Biomass versus Fossil Fuel CO2 ____________________________________________________ 33 8 Data Quality and Sources _________________________________________________ 34 8.1 Data Sources______________________________________________________________ 34 8.2 Data Quality ______________________________________________________________ 35 9 Results and Discussion____________________________________________________ 36 9.1 Presentation of Results _____________________________________________________ 36 9.2 Explanation of Negative Flows _______________________________________________ 36 9.3 Hydrocarbon Emission _____________________________________________________ 36 9.4 Time-Space Implications of Emissions_________________________________________ 36 9.5 Life Cycle Energy Balance __________________________________________________ 36 9.6 LCI for Burning versus Diverting Bagasse to Ethanol: Enzyme Process ____________ 38 9.6.1 Resource Depletion ______________________________________________________________ 40 9.6.2 Air Pollutants __________________________________________________________________ 40 9.6.3 Waste Generation _______________________________________________________________ 40 9.6.4 Energy Consumption and GHGs____________________________________________________ 40 9.7 LCI for Burning versus Diverting Bagasse to Ethanol: Dilute Acid Process __________ 48 9.7.1 Resource Depletion ______________________________________________________________ 49 9.7.2 Air Pollutants __________________________________________________________________ 49 9.7.3 Waste Generation _______________________________________________________________ 49 9.7.4 Energy Consumption and GHGs____________________________________________________ 49 9.8 LCIA for Burning versus Diverting Bagasse to Ethanol __________________________ 49 9.8.1 Greenhouse Potential ____________________________________________________________ 50 9.8.2 Natural Resource Depletion Potential ________________________________________________ 50 9.8.3 Air Acidification Potential ________________________________________________________ 51 Environmental Life Cycle Implications of Using Bagasse-Derived Ethanol as a Gasoline Oxygenate in Mumbai (Bombay) Final Report by K. L. Kadam iv 9.8.4 Eutrophication Potential __________________________________________________________ 51 9.8.5 Human Toxicity Potential _________________________________________________________