Life cycle-based air quality modelling for technology assessment and policy applications: the concept and technical considerations Weimin Jiang, Steven C. Smyth, Qiangliang Li

CMAS Conference, Chapel Hill2Oct 16-18, 2006 Outline Introduction Two current approaches in analysing air quality impact of technologies The concept of life cycle-based air quality modelling (lcAQM) for technology assessment and policy applications Technical considerations for conducting lcAQM Summary and discussions

CMAS Conference, Chapel Hill3Oct 16-18, 2006 Introduction A crucial and pressing issue facing human civilization: Rapidly expanding human material needs/desire vs. Availability and sustainable use of natural resources The three pillars of sustainable development: Social, economic, and environmental Possible civilized solution: New and emerging technologies, e.g., biofuels Key question: Which technologies are really “sustainable”? What can we (air quality modellers) contribute? Understand potential impact of the technologies on air quality Who need the answers? − Policy community − Industry − Anyone who breathes

CMAS Conference, Chapel Hill4Oct 16-18, 2006 LCA = life cycle assessment Definition by ISO 14040: “the compilation and evaluation of the inputs, outputs, and potential environmental impacts of a product system throughout its life cycle” Life cycle: from cradle to grave; individual stages or as a whole e.g. from biomass feedstock production to biofuel combustion ISO 14042: standard on life cycle impact assessment ISO GaBi (a LCA software) impact categoryphoto-oxidant formation category indicatortropospheric ozone formation characterization factorphotochemical ozone creation potential (POCP) Current approach: LCA (1)

Emissions and impact assessment are based on a functional unit: e.g., 1 vehicle-km travelled (VKT), 1 liter of fuel, 1 MJ energy,... Species EmissionsPOCPTropos. O 3 formation (g/VKT)(g C 2 H 4 -eq/g emis)(g C 2 H 4 -eq/VKT) DieselSD100 DieselSD100 Carbon monoxide1.14E E E E E-02 Nitrogen dioxide5.31E E E E E-02 Nitrogen oxides2.33E E E E E-02 Alkene (unspecified)2.49E E E E E-05 Benzene7.58E E E E E-05 Butane7.29E E E E E-04 Xylene1.03E E E E E-04 VOC (unspecified)2.03E E E E E-05 TOTAL Current approach: LCA (2)

CMAS Conference, Chapel Hill6Oct 16-18, 2006 Current approach: 3-D AQM Use a 3-D air quality model, such as CMAQ, CAMx, CALGRID,... Detailed atmospheric chemical and physical processes Spatially, temporally, and chemically resolved Technology scales considered Impact on atmospheric pollutant concentrations Most (if not all) focused on certain life cycle stage(s), e.g., emissions from vehicle engine combustion

CMAS Conference, Chapel Hill7Oct 16-18, 2006 The lcAQM concept lcAQM: life cycle-based Air Quality Modelling –a natural advance of the current AQM practice with life cycle thinking –integrate the LCA framework defined by ISO with the current AQM approach Example to illustrate the concept and considerations The potential impact of large scale production and application of SunDiesel as a transportation fuel on air quality in Canada and the U.S. from a whole life cycle perspective. The results are to be used to support policy decisions regarding biofuel development.

An operational lcAQM framework

CMAS Conference, Chapel Hill9Oct 16-18, 2006 Technical consideration: System boundary definition Chemical, physical, and engineering processes in different life cycle stages to be included in the analysis SunDiesel: –Introduced by Choren Industries in Germany –Can be used directly to replace petroleum diesel –Made from cellulose, hemicellulose, and lignin, which are major components of a wide variety of biomasses –Produced through two major chemical processes biomass gasification  syngas (CO, H 2, CO 2, etc) Fisher-Tropsch synthesis: syngas  SunDiesel

CMAS Conference, Chapel Hill10Oct 16-18, 2006 Life cycle of SunDiesel as a transportation fuel

CMAS Conference, Chapel Hill11Oct 16-18, 2006 The biomass production stage

The SunDiesel production stage

CMAS Conference, Chapel Hill13Oct 16-18, 2006 SunDiesel production: an energy self-sufficient model

CMAS Conference, Chapel Hill14Oct 16-18, 2006 Technical consideration: Modelling scenario definition/design (1) Possible locations and timing of industrial and agricultural operations in different life cycle stages Technology application scales and penetration levels Uncertainties in assumptions: sensitivity tests SunDiesel: –Canada and continental US –Full year of 2050: substantial displacement of petroleum oil by bio-fuels (?)

CMAS Conference, Chapel Hill15Oct 16-18, 2006 –Biomass-growing locations: Land-use coverage in Canada and US Forest logging site  logging wood residues Agriculture and other suitable land  energy crops Energy crop yields Conversion efficiencies of biomass  SunDiesel Needs of food crops, animal feed, and energy crops –SunDiesel production plant locations: Close to the biomass growth or collection sites Competing factors of plant sizes and distances from the biomass sites Technical consideration: Modelling scenario definition/design (2)

CMAS Conference, Chapel Hill16Oct 16-18, 2006 Technical consideration: Emissions (1) Life cycle emissions data: scarce, a major barrier, and require significant efforts Life cycle thinking in E.I. development: –Cross-checking emissions between different life cycle stages –Ensure completeness and self-consistency among life cycle stages E.I. used in AQM + LCI (life cycle inventory) used in LCA: emissions data in GaBi, SimaPro, EcoInvent, etc. Spatial surrogate/ratios, temporal factors: based on scenario definition/design assumptions and to be studied through sensitivity tests

CMAS Conference, Chapel Hill17Oct 16-18, 2006 Removal of old-technology emissions: analysis of SIC & SCC codes, and emis. source descriptions SunDiesel: –Emissions from some life cycle stages can be assembled or derived: GaBi: Functional unit-based NOx, VOC, SO 2, PM, and heavy metal emissions for various processes related to different fertilizers, fuels, and power Analysis of fertilizer and energy needs for biomass growth, and transportation, storage, and dispensing Speciated VOC emissions  VOC speciation profiles for some life cycle stages Technical consideration: Emissions (2)

CMAS Conference, Chapel Hill18Oct 16-18, 2006 –Measured emissions from SunDiesel production not publicly available  a major challenge for the SunDiesel lcAQM. Effort in estimating the emissions with great uncertainties Need emissions data: Choren or other FT processes, flash gas combustion –Spatial surrogate ratios: reflect assumed spatial distributions of agricultural & industrial sources within life cycle stages –Temporal factors: reflect seasonality of agriculture and industrial operational schedules –Emissions from petroleum diesel life cycle: to be partially removed to reflect displacement of the fuel by SunDiesel Technical consideration: Emissions (3)

CMAS Conference, Chapel Hill19Oct 16-18, 2006 Technical consideration: Model implementation and result analysis Emissions grouped by major life cycle stages: e.g., feedstock generation, fuel production, fuel transportation, storage, and dispensing, and fuel usage for transportation purposes, etc. Model runs with all the emissions, and sensitivity runs with or without emissions from certain life cycle stages  the air quality impact of individual life cycle stages or whole life cycle

CMAS Conference, Chapel Hill20Oct 16-18, 2006 Summary and discussions lcAQM = 3-D AQM practice with life cycle thinking for analysing technology impact on air quality. Special considerations: –System boundary definition: lcAQM foundation –Modelling scenario design: lcAQM foundation –Emissions data collection, estimation, and analysis: Data availability Life cycle thinking in E.I. development for AQM AQM E.I. + LCI Spatial and temporal information associated with life cycle stages –Model runs and analysis: Based on the whole life cycle or individual life cycle stages

CMAS Conference, Chapel Hill21Oct 16-18, 2006 Acknowledgements Helmut Roth and Albert Chan, ICPET/NRC: Review and comments Natural Resources Canada: Funding for SunDiesel analysis

CMAS Conference, Chapel Hill22Oct 16-18, 2006