Presentation on theme: "Life Cycle Assessment: Laying the Foundation for a Transparent Supply Chain Shopping Bag Case Study September 26, 2013 Dr. Anahita Williamson Director."— Presentation transcript:
1 Life Cycle Assessment: Laying the Foundation for a Transparent Supply Chain Shopping Bag Case Study September 26, Dr. Anahita Williamson Director Kate Winnebeck LCACP, Senior EHS Specialist New York State Pollution Prevention Institute at RIT
2 Life Cycle AssessmentLife Cycle Assessment (LCA) is a technique used to quantify the environmental impact of a product from raw material acquisition through end of life disposition (cradle-to-grave)Material ExtractionProcessingComponent FabricationProduct AssemblyPackaging & DistributionUseEnd of Use ProcessingReuseRemanufactureHelps identify the environmental impact of processes in product design decisionsCommonly used to quantify the environmental impacts of products to enable comparisons between different products performing the same functionRecycleWaste Treatment
3 LCA MethodologyA Life Cycle Assessment is carried out in four distinct phases: (ISO 14040, 14044)Step 1: Goal definition and scoping. Identify the LCA's purpose, the products of the study, and determine the boundaries. (what is and is not included in the study)Step 2: Life-cycle inventory. Quantify the energy and raw material inputs and environmental releases associated with each life cycle phase.Step 3: Impact analysis. Assess the impacts on human health and the environment.Step 4: Report results. Evaluate opportunities to reduce energy, material inputs, or environmental impacts at each stage of the product life-cycle.
4 Step 1: Goal Definition and Scoping Define the goal:Intended application of the studyIntended audienceDefine the scope:Identify the product system to be studiedDefine the functional unitDefine the boundaries of the product systemIdentify assumptions and limitations of the studySelect impact categories to be included
5 Today’s ExampleYou own a grocery store and customers are starting to request that you sell reusable shopping bags. You are curious which type of bag has the lowest environmental impact. In order to quantify and compare the bag options, a streamlined LCA is performed.Goal:Determine which grocery bag – single use paper, single use plastic, reusable plastic, or reusable cotton – has the lowest environmental impactSingle use plastic – HDPEReusable –polypropylene – Wegman’s tote (woven bag)Sustainability Victoria, Comparison of existing life cycle analysis of shopping bag alternatives, Apr07.
6 Draw the System Boundaries Assumptions:All bags are manufactured 100km from the customerAll bags travel 10km from the customer to the end of lifeHalf of paper bags are recycled at end of life, half go to landfillPlastic & cotton bags go to landfill at end of lifeAs a group, draw the boundaries or process flow of the system
7 System Boundaries Material Extraction Processing Bag Manufacture Packaging & DistributionUseEnd of LifeSingle use & reusable plastic bagExtracting petroleumTransform petroleum into plasticForm plastic into bagsPackaging & DistributionUseLandfillPaper bagCutting down treesTransform trees into paperForm paper into bagsPackaging & DistributionUse50/50 to Landfill & Recycling
8 Functional UnitThe functional unit is a measure of the function of the studied systemProvides a reference to which the inputs and outputs can be relatedEnables comparison of two essentially different systemsExamplesThe functional unit for a paint system may be defined as the unit surface protected for 10 yearsThe functional unit for a printer may be defined as the number of printed pages of an acceptable print qualityThe functional unit for power generation systems may be defined as 1kWh of electricity
9 Functional UnitThe amount of shopping bags consumed by a household to carry 70 grocery items home from the supermarket each week for 52 weeksBag TypeSingle use plasticSingle use paperReusable plasticReusable cottonMaterialHDPEUnbleached Kraft paperPolypropyleneCottonMass per bag7g42.6g95g85gRelative Capacity10.91.1Bags per Year5205784.55Mass bags per year3640gg432.25g386.75g
10 Step 2: Life Cycle Inventory Highly data intensiveDetailed mass & energy balances performed over life-cycleAdvantages: measure data & define baseline metrics of life-cycle processesChallenges: Assumptions made when data unavailable
11 Step 2: Life Cycle Inventory End of use processingCustomer useDistributionManufacturingMaterialsInventory collected from multiple sourcesInputsEnergyRawMaterialsOutputsProductsAir, Water andSolid Emissionsdatabase
12 Toner Life-cycle Inventory Looking at final systemRef: A.Ahmadi,et.al, J.Clean.Prod., 2003
13 Toner Life-cycle Inventory Toner Manuf. really does not have major impact on overall life-cycle of the tonerShows how the different sections of the system compare to one anotherThe post-production processes dominate the categoriesLink between air emissions and energy use, which results from the much larger quantities of energy related air emissions in relation to manufacturing process air emissionsCustomer use is the most energy intensive process of the system energy required to transfer the metric ton of toner onto the paperEnd of use Processing also has a significant impact mainly from the removal of the toner from the paper that is recycled (de-inking process); De-inking also accounts for large amount of wastewater and solid waste (toner that is removed from paper; note: waste paper not included in analysis)Toner manuf. Process impacts small compared to post-consumer processesRef: A.Ahmadi,et.al, J.Clean.Prod., 2003
14 Impact Assessment Results Impact assessment converts the inventory into impact categories or end points which details the human health and environmental effects.
15 High Density Polyethylene Inventory Peer reviewed datasets imbedded in softwareData has been collected by others and represents actual operationsInclude:Known inputsEmissions to airEmissions to waterEmissions to soilWastes and emissions sent to treatmentAbility to modify datasets based on your own data2. As a group, choose one of the four bags and list the processes that are included in the inventory
16 Life Cycle Inventory Single Use Plastic Bag Polyethylene, HDPE, granulate3640gStretch blow mouldingTransport, 100km manufacturing to customer0.364tkmTransport, municipal waste collection, 10km customer to landfill0.0364tkmDisposal, polyethylene, 0.4% water, to sanitary landfillSingle Use Paper BagKraft paper, unbleached, at plantgProduction of paper bags2.4623tkmTransport, municipal waste collection, 10km customer to landfill/recyclingtkmDisposal, packaging paper, to sanitary landfill12311gRecycling paperReusable Plastic BagPolypropylene, granulate432.25gExtrusion, plastic filmTransport, 100km manufacturing to customertkmTransport, municipal waste collection, 10km customer to landfilltkmDisposal, polypropylene, to sanitary landfillReusable Cotton BagTextile, woven cotton, at plant386.75gtkmtkmDisposal, inert material, to sanitary landfill
17 Step 3: Impact Assessment Converts the inventory into impact categories or mid/end points which explain the environmental effectImpact categories may include: carcinogens, respiratory organics and inorganics, climate change, radiation, ozone layer, ecotoxicity, acidification/eutrophication, land use, minerals, fossil fuelsCan apply weights to impact categories
18 Single Score Indicator Impact AssessmentLife Cycle InventoryNOxSOxPesticidesHeavy metalsCO2VOCsParticulatesChemicalsImpact CategoriesConcentration in air, water, foodConcentration greenhouse gasesChanged pH and nutrient availabilityChange in habitatFossil fuel availabilityCategory IndicatorsLocal effects on speciesClimate changeOzone layer depletionRadiationRespiratory effectsCancer cases and typesSurplus energyDamage CategoriesSingle Score IndicatorHuman HealthEcosystem QualityMineral & Fossil ResourcesFATE ANALYSIS – when a chemical is released, it may end up in the air, water, or soilThis step looks at the properties of the substance to determine where it will end up – ie. water soluble substance will have a higher concentration in waterAlso considers degradability of the substanceModels transfer of the chemical between environmental compartments and degradation of the chemical – result is the concentration of the substance in air, water, soil, & foodEXPOSURE ANALYSIS – determine how much of a substance is taken in by people & the environmentEFFECT ANALYSIS – predict the types and frequencies of effects based on the amount taken in by people & the environment in the exposure analysisDAMAGE ANALYSIS – predicted diseases/effects are translated to one unitIe. EcoIndicator 99:Human Health = DALY = disability adjusted life yearEcosystem Quality = loss of species over a certain areaResources = surplus energy needed for future extraction of minerals and fossil fuelsNormalization & Weighting – determine the importance of effects and weigh them appropriatelyCan use weighting factors built into impact assessment models or can modify models to apply your own weightingIe. EcoIndicator 99 – human health & ecosystem are equivalent, resources is ½ as important, determined by panel of scientific expertsFate analysisExposure & effect analysisDamage analysisNormalization & weighting
21 Step 4: Report ResultsLife cycle interpretation: findings of the inventory analysis or impact assessment are evaluated in relation to the goal and scope of the study to reach conclusions and recommendationsIdentify significant issuesEvaluate results for completeness, consistency, and sensitivity of the dataDraw conclusions & make recommendations consistent with the goal & scope of the study
22 Interpreting ResultsWhich bag has the lowest environmental impact? Which bag has the highest?Let’s consider cost of the bags.As the store owner, does the cost information change which type of bag you would promote? How? As a shopper, does the cost information change which type of bag you would use? How?Bag TypeSingle use plasticSingle use paperReusable plasticReusable cottonMaterialHDPEUnbleached Kraft paperPolypropyleneCottonCost per bag$0.02$0.07$1$6Cost per year$10.40$40.46$4.55$27.30
23 Anahita Williamson, PhD DirectorPhone:Kate Winnebeck, LCACP Sr. Environmental Health & Safety SpecialistPhone:New York State Pollution Prevention Institute