The Materials Life CycleThe Materials Life Cycle

Life Cycle AssessmentLife Cycle Assessment

LCA traces the cycle of materials and processesLCA traces the cycle of materials and processes

Documents resources consumed, emissions excretedDocuments resources consumed, emissions excreted

Life Cycle AssessmentLife Cycle Assessment

Different levels are appropriate:Different levels are appropriate:

Full LCA scrutinizing every aspect (tedious, expensive)Full LCA scrutinizing every aspect (tedious, expensive)

A Sketch-like overviewA Sketch-like overview

ApproximateApproximate

anything in betweenanything in between

NaturalNaturalResourcesResources

MaterialMaterialProductionProduction

ProductProductManufactureManufacture

ProductProductUseUse

ProductProductDisposalDisposalEmissionsEmissions::

COCO22, NO, NOxx, SO, SOxx

ParticulatesParticulatesToxic wasteToxic waste

Low grade heatLow grade heat

EnergyEnergy

FeedstockFeedstock

TransportationTransportation

EmissionsEmissions

There is a wide range of emissions:There is a wide range of emissions:

Carbon dioxide, sulfur oxides, nitrous oxides, low grade Carbon dioxide, sulfur oxides, nitrous oxides, low grade heat, gas, liquid and solid wasteheat, gas, liquid and solid waste

In low concentrations, most of these are harmless. But in In low concentrations, most of these are harmless. But in high concentrations they can be damaging.high concentrations they can be damaging.

The sum of these unwanted by products often exceeds the The sum of these unwanted by products often exceeds the capacity of the environment to handle them.capacity of the environment to handle them.

Emissions damageEmissions damage

If the damage is local and the responsible agent deals with If the damage is local and the responsible agent deals with the cost of containing and remediating, we say the the cost of containing and remediating, we say the environmental cost is environmental cost is internalizedinternalized..

If the damage is global and the agent is not held If the damage is global and the agent is not held responsible, the cost is spread over society and we say the responsible, the cost is spread over society and we say the environmental cost is environmental cost is externalizedexternalized..

Which is greener?Which is greener?

Life-cycle analysis is a method in which the energy and raw Life-cycle analysis is a method in which the energy and raw material consumption, emissions and other factors are material consumption, emissions and other factors are measured, analyzed and evaluated over the product’s measured, analyzed and evaluated over the product’s entire life. entire life.

Life-Cycle Analysis attempts to measure the “cradle to Life-Cycle Analysis attempts to measure the “cradle to grave” impact on the ecosystem.grave” impact on the ecosystem.

LCAs started in the early 1970s, initially to investigate the LCAs started in the early 1970s, initially to investigate the energy requirements for different processes.energy requirements for different processes.

Emissions and raw materials were added later.Emissions and raw materials were added later.

LCAs are considered to be the most comprehensive LCAs are considered to be the most comprehensive approach to assessing environmental impact.approach to assessing environmental impact.

cloth vs. disposable diaperscloth vs. disposable diapers

1990 –The American Paper Institute finds disposable diapers to 1990 –The American Paper Institute finds disposable diapers to be preferable. be preferable.

1991 – The National Association of Diaper Services concludes 1991 – The National Association of Diaper Services concludes the opposite.the opposite.

1992 – Procter & Gamble reverses the conclusion once more.1992 – Procter & Gamble reverses the conclusion once more.

Each time, additional considerations were brought in: -indirect of paper Each time, additional considerations were brought in: -indirect of paper production (increasing impacts of disposables) -production of detergents production (increasing impacts of disposables) -production of detergents (increasing impacts of washing cloth) (increasing impacts of washing cloth)

1992 – New study by Franklin Associates, concluding that the 1992 – New study by Franklin Associates, concluding that the answer depends on whether one looks at energy or water or answer depends on whether one looks at energy or water or solid waste. solid waste.

Franklin and AssociatesFranklin and Associates

Total energy used by each diaper type in one year. Total energy used by each diaper type in one year.

Feedstock and process energy includes energy used Feedstock and process energy includes energy used through cotton growing, material processing and diaper through cotton growing, material processing and diaper manufacture. manufacture.

It also includes energy used and embodied in bleach and It also includes energy used and embodied in bleach and detergent. detergent.

Franklin and AssociatesFranklin and Associates

Volume of solid waste per year. Volume of solid waste per year.

includes waste used to produce the diaper such as raw includes waste used to produce the diaper such as raw material production and process, manufacture trimmings, material production and process, manufacture trimmings, and ash from electricity generation. and ash from electricity generation.

Post consumer waste refers to substances thrown out: the Post consumer waste refers to substances thrown out: the diaper itself, child waste, and packaging. diaper itself, child waste, and packaging.

Franklin & Assoc.Franklin & Assoc.

Franklin & Assoc.Franklin & Assoc.

What is the conclusion?What is the conclusion?

Is energy or waste more important?Is energy or waste more important?

Other factors possibly involved as wellOther factors possibly involved as well

When conclusions are easily reversed, probably too close to When conclusions are easily reversed, probably too close to call?call?

MethodologiesMethodologies

Initially, numerous variants of LCA “methods” were Initially, numerous variants of LCA “methods” were developed/investigated, but today there is consensus that developed/investigated, but today there is consensus that there is only one basic method with a large number of there is only one basic method with a large number of variantsvariants

Currently IS0 14040-14043 is considered to be the LCA Currently IS0 14040-14043 is considered to be the LCA standard.standard.

Four steps of LCAFour steps of LCA1.1. Goal definition (ISO 14040)Goal definition (ISO 14040)The basis and scope of the evaluation are defined.The basis and scope of the evaluation are defined.

2.2. Inventory Analysis (ISO 14041)Inventory Analysis (ISO 14041)Process tree for raw material to wasteProcess tree for raw material to wasteMass and energy balances are computedMass and energy balances are computedAll emissions and consumptions are accountedAll emissions and consumptions are accounted

3.3. Impact Assessment (ISO 14042)Impact Assessment (ISO 14042)Emissions and consumptions are translated into environmental effects.Emissions and consumptions are translated into environmental effects.The environmental effects are grouped and weighted. The environmental effects are grouped and weighted.

4.4. Interpretation/Assessment (ISO 14043)Interpretation/Assessment (ISO 14043)Areas for improvement are identified.Areas for improvement are identified.

1. Goal definition1. Goal definition

establish establish beforehand beforehand what purpose the model is to serve, what purpose the model is to serve, what one wishes to study, what depth and degree of what one wishes to study, what depth and degree of accuracy are required, and what will ultimately become the accuracy are required, and what will ultimately become the decision criteria.decision criteria.

In addition, the system boundaries - for both time and place In addition, the system boundaries - for both time and place - should be determined.- should be determined.

2. Inventory Analysis2. Inventory Analysis

inputs and outputs of all processes in terms of material and inputs and outputs of all processes in terms of material and energy.energy.

process tree showing events in a product’s life-cycle and process tree showing events in a product’s life-cycle and their interrelations.their interrelations.

the emissions from each process and the resources (raw the emissions from each process and the resources (raw materials) used for each eventmaterials) used for each event

establish (correct) material and energy balance for each establish (correct) material and energy balance for each process stage and event.process stage and event.

Raw Materials AcquisitionRaw Materials Acquisition

ManufacturingManufacturing

Use / Re-use / MaintenanceUse / Re-use / Maintenance

Recycling / Waste Mgmt.Recycling / Waste Mgmt.

Inputs:Inputs:

Raw MaterialsRaw Materials

EnergyEnergy

Outputs:Outputs:

Atmospheric Atmospheric EmissionsEmissions

Waterborne WasteWaterborne Waste

Solid WasteSolid WasteCo-ProductsCo-Products

Other ReleasesOther Releases

System BoundarySystem Boundary

Processes:Processes:

Coffee machine (simplified)Coffee machine (simplified)

Coffee machine LCICoffee machine LCI

Problems with LCIProblems with LCI

The inventory phase usually takes a great deal of time and The inventory phase usually takes a great deal of time and effort and mistakes are easily made.effort and mistakes are easily made.

There is data on impact of different materialsThere is data on impact of different materials

the data is often inconsistent and not directly applicable the data is often inconsistent and not directly applicable due to different goals and scope.due to different goals and scope.

hoped that the quantity and quality of data will improve hoped that the quantity and quality of data will improve in the future.in the future.

Results are generalized improperly.Results are generalized improperly.

3. Impact Assessment3. Impact Assessment

The impact assessment focuses on characterizing the type The impact assessment focuses on characterizing the type and severity of environmental impact more specifically.and severity of environmental impact more specifically.

There are different ways to weight and assess impacts.There are different ways to weight and assess impacts.

EPA 10 most wantedEPA 10 most wanted

Impact:Impact:

Global Warming Potential (GWP)Global Warming Potential (GWP)

Ozone Depletion Potential (ODP)Ozone Depletion Potential (ODP)

Photochemical Oxidant Potential (PCOP)Photochemical Oxidant Potential (PCOP)

Acidification PotentialAcidification Potential

EutrificationEutrification

Health Toxicity (Cancer)Health Toxicity (Cancer)

Health Toxicity (Non-Cancer)Health Toxicity (Non-Cancer)

Health Toxicity (Air Pollutants)Health Toxicity (Air Pollutants)

Eco-Toxicity PotentialEco-Toxicity Potential

Fossil Fuel UseFossil Fuel Use

Measure:Measure:

kg COkg CO22 Equivalent Equivalent

kg CFC Equivalentkg CFC Equivalent

kg NOkg NOXX Equivalent Equivalent

H+ Moles EquivalentH+ Moles Equivalent

kg Nitrogen Equivalentkg Nitrogen Equivalent

kg Benzene Equivalentkg Benzene Equivalent

kg Toluene Equivalentkg Toluene Equivalent

kg: DALYs Equivalentkg: DALYs Equivalent

kg 2,4-D Equivalentkg 2,4-D Equivalent

MJ SurplusMJ Surplus//Extracted EnergyExtracted Energy

Environmental effectEnvironmental effectMaterial/impactMaterial/impact

greenhouse effectgreenhouse effectgreenhouse effectgreenhouse effect

ozone layer depletionozone layer depletionozone layer depletionozone layer depletion

eutrophicationeutrophicationeutrophicationeutrophication

depletion of abiotic resourcesdepletion of abiotic resourcesdepletion of abiotic resourcesdepletion of abiotic resources

(summer) smog(summer) smog(summer) smog(summer) smog

acidificationacidificationacidificationacidification

coppercopperCOCO22

CFCCFCSOSO22

NONOxx

PhosphorousPhosphorousVOCsVOCs

heavy metalsheavy metalsPCBPCB

pesticidespesticidesstyrenestyrene

coppercopperCOCO22

CFCCFCSOSO22

NONOxx

PhosphorousPhosphorousVOCsVOCs

heavy metalsheavy metalsPCBPCB

pesticidespesticidesstyrenestyrene

eco-toxicityeco-toxicityeco-toxicityeco-toxicity

depletion of biotic resourcesdepletion of biotic resourcesdepletion of biotic resourcesdepletion of biotic resources

human toxicityhuman toxicityhuman toxicityhuman toxicity

odorodorodorodor

4. Interpretation4. Interpretation

The final step in Life-Cycle Analysis is to identify areas for improvement.The final step in Life-Cycle Analysis is to identify areas for improvement.

Consult the original goal definition for the purpose of the analysis and the Consult the original goal definition for the purpose of the analysis and the target group.target group.

Life-cycle areas/processes/events with large impacts (i.e., high numerical Life-cycle areas/processes/events with large impacts (i.e., high numerical values) are clearly the most obvious candidatesvalues) are clearly the most obvious candidates

However, what are the resources required and risk involved?However, what are the resources required and risk involved?

Good areas of improvement are those where large improvements can be made with Good areas of improvement are those where large improvements can be made with minimal (corporate) resource expenditure and low risk.minimal (corporate) resource expenditure and low risk.

Paper or plastic?Paper or plastic?

Goal?Goal?

Inventory AnalysisInventory Analysis

Impact assessmentImpact assessment

AnalysisAnalysis

InventoryInventory

Materials: Paper and polyethylene + additives, colorants, Materials: Paper and polyethylene + additives, colorants, etc.etc.

Processes: film blow, paper forming, printing, etc.Processes: film blow, paper forming, printing, etc.

1.5 plastic bags = 1.0 paper bags 1.5 plastic bags = 1.0 paper bags

Waste water, green house gassesWaste water, green house gasses

Recycling? Composting?Recycling? Composting?

How to account for human variability?How to account for human variability?

Plastic BagsPlastic Bags

Paper BagsPaper Bags

Paper or plastic?Paper or plastic?

  Paper PlasticRaw materials Wood OilEnergy to make (MJ) 1.7 1.5Solid waste (g) 50 14Total emissions to air (kg) 2.6 1.1CO2 equivalents (kg) 0.23 0.53

Plastic bags generate 39% less greenhouse gas emissions Plastic bags generate 39% less greenhouse gas emissions than uncomposted paper bags, and 68% less greenhouse than uncomposted paper bags, and 68% less greenhouse gas emissions than composted paper bags. gas emissions than composted paper bags.

Plastic bags consume less than 6% of the water needed Plastic bags consume less than 6% of the water needed to make paper bagsto make paper bags

Plastic grocery bags consume 71% less energy during Plastic grocery bags consume 71% less energy during production than paper bags.production than paper bags.

total non-renewable energy consumed in plastic bag life total non-renewable energy consumed in plastic bag life is 36% less than paper bags, and up to 64% less than is 36% less than paper bags, and up to 64% less than that consumed by biodegradable plastic bags.that consumed by biodegradable plastic bags.

Using paper sacks generates almost five times more solid Using paper sacks generates almost five times more solid waste than using plastic bags.waste than using plastic bags.

After three uses, reusable plastic bags are superior to all After three uses, reusable plastic bags are superior to all other types of disposable bagsother types of disposable bags

ManufacturingManufacturing

Paper consumes twice as much water and emits about 60% Paper consumes twice as much water and emits about 60% more greenhouse gases than plastic.more greenhouse gases than plastic.

biodegradable plastic bags generate higher levels of biodegradable plastic bags generate higher levels of greenhouse gas emissions, atmospheric acidification and greenhouse gas emissions, atmospheric acidification and eutrophificationeutrophification

Paper or plastic?Paper or plastic?