Comparison of Life‐Cycle Inventory Databases: A Case Study Using Soybean Production

Three established life-cycle inventories of agricultural operations were used to generate air emissions data for soybean production: the greenhouse gases, regulated emissions, and energy use in transportation (GREET) model; the economic input-output life-cycle assessment (EIO-LCA) model; and SimaPro software equipped with the Franklin database. EIO-LCA and GREET baseline data were compared to evaluate differences in boundary definitions that apply specifically to U.S. soybean agriculture and processing, which resulted in several major findings. The EIO model estimated for emissions of particulate matter less than 10 micrograms (PM10) resulting from wind erosion that were not included in GREET, but neglected indirect nitrous oxide (N2O) and nitrogen oxides (NOx) emissions from fertilizer application. EIO also assumed significantly lower process energy requirements and lower volatile organic compounds (VOC) for soybean crushing and oil extraction. The GREET and SimaPro models were compared using identical boundary and assumption data, to reveal major discrepancies in fundamental assumptions of energy inventories. Key emission factors varied by several orders of magnitude for basic energy generation and combustion processes, potentially impacting results for any inventory analysis that contains significant energy consumption. The Franklin database assumed VOC and sulfur oxides (SOx) emissions more than an order of magnitude higher than GREET for all categories investigated, with significantly lower N2O and methane (CH4) emission factors.

[1]  James A. Duffield,et al.  Estimating the net energy balance of corn ethanol. Agricultural economic report , 1995 .

[2]  N. H. Witte.  Soybean Meal Processing and Utilization , 1995 .

[3]  John Sheehan,et al.  Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban Bus , 1998 .

[4]  Mark A. Delucchi.  Emissions of Non-CO2 Greenhouse Gases From the Production and Use of Transportation Fuels and Electricity , 1997 .

[5]  Zane R. Helsel,et al.  Energy in plant nutrition and pest control , 1987 .

[6]  John R. Ehrenfeld,et al.  The Importance of LCAs—Warts and All , 1997 .

[7]  B. E. Dale,et al.  Biobased Industrial Products: Bioprocess Engineering When Cost Really Counts , 1999, Biotechnology progress.

[8]  John Sheehan,et al.  Life cycle inventory of biodiesel and petroleum diesel for use in an urban bus. Final report , 1998 .

[9]  J. W. Owens.  Life‐Cycle Assessment: Constraints on Moving from Inventory to Impact Assessment , 1997 .

[10]  S. Joshi.  Product Environmental Life‐Cycle Assessment Using Input‐Output Techniques , 1999 .

[11]  D. Kaplan,et al.  Biopolymers from Renewable Resources , 1998 .

[12]  J. L. Baker,et al.  Nitrate-Nitrogen in Tile Drainage as Affected by Fertilization 1 , 1981 .

[13]  Domenico Grasso,et al.  Industrial Ecology: Policy Potential and Research Needs , 2003 .

[14]  DeLuchi.  Emissions of greenhouse gases from the use of transportation fuels and electricity. Volume 2: Appendixes A--S , 1993 .

[15]  Laura L. Kosbar,et al.  Introducing Biobased Materials into the Electronics Industry , 2000 .

[16]  Manfred Lenzen,et al.  Differential Convergence of Life‐Cycle Inventories toward Upstream Production Layers , 2002 .

[17]  E. Peereboom,et al.  Influence of Inventory Data Sets on Life‐Cycle Assessment Results: A Case Study on PVC , 1998 .

[18]  Braden Allenby,et al.  Matrix Approaches to Abridged Life Cycle Assessment , 1995 .

[19]  R. Beattie,et al.  Everything you already know about EIA (but don't often admit) , 1995 .

[20]  Robert U. Ayres,et al.  Life cycle analysis: A critique , 1995 .

[21]  Gregory A. Norris,et al.  A Transparent, Interactive Software Environment for Communicating Life‐Cycle Assessment Results: An Application to Residential Windows , 2001 .

[22]  M. Deluchi.  Emissions of greenhouse gases from the use of transportation fuels and electricity. Volume 1, Main text , 1991 .

[23]  Michael Q. Wang.  GREET 1.5 - transportation fuel-cycle model - Vol. 1 : methodology, development, use, and results. , 1999 .

[24]  Arpad Horvath,et al.  Economic Input–Output Models for Environmental Life-Cycle Assessment , 1998 .

[25]  Allen L. White,et al.  Life Cycle Assessment , 1993 .

[26]  M. Kunz,et al.  Polymers and surfactants on the basis of renewable resources. , 2001, Chemosphere.

[27]  Wassily Leontief.  Input-Output Economics , 1966 .

[28]  Manfred Lenzen,et al.  Errors in Conventional and Input‐Output—based Life—Cycle Inventories , 2000 .