Life Cycle Analysis

8803 Business and the Environment

Beril ToktayCollege of Management

Georgia Institute of Technology

What is a Product Life Cycle?

Raw materials

mining

Primary materials

production

Component

manufacture

Productassembly &distribution

Productuse &

maintenance

Product

disposal

ServiceSupply Chain

Product Life Cycle

The boxes are process groups called life cycle stages (system components).The arrows are economic material flows (relationships between system components)

Products interact with their environment in many ways

Production waste and emissions

Transport and distribution waste and emissions

Use and maintenance waste and emissions

End-of-life waste andemissions

Raw materials

mining

Primary materials

production

Component

manufacture

Finalproduct

assembly

Productuse and

maintenance

Product

disposal

Service

MaterialsEnergy

MaterialsEnergy

MaterialsEnergy

MaterialsEnergy

MaterialsEnergy

MaterialsEnergy

Cupuse

Landfill,recycling

Service

Harvesting

trees

logs

Woodyard

wood chips

Digester,washing,bleaching

steam,chlorine (?)

pulp

Forming

paper cup

adhesive,heat

Cupuse

Landfill,recycling

Service

Catalyticdehydro-genation

catalyst

styrene

Drilling

oil

oil, gas

gas

Poly-merization,

blowing

PS cup

solvent,Initiator,blowing agent (pentane or CO2, used to be CFC)

Refinery

ethyl benzene

catalyst

Example: Paper Cup vs. Polystyrene CupExample: Paper Cup vs. Polystyrene Cup

History and definition of LCADefinition of LCA according to ISO 14040:

LCA is a technique […]compiling an inventory of relevant inputs and outputs of a product system; evaluating the potential environmental impacts associated with those inputs and outputs;and interpreting the results of the inventory and impact phases in relation to the objectives of the study.

• Late 1960s, first Resource and Environmental Profile Analyses (REPAs) (e.g. in 1969 Coca Cola funds study on beverage containers)• Early 1970s, first LCAs (Sundström,1973,Sweden, Boustead,1972, UK, Basler & Hofmann,1974,Switzerland, Hunt et al.,1974 USA)• 1980s, numerous studies without common methodology with contradicting results • 1993, SETAC publishes Guidelines for Life-Cycle Assessment: A ‘Code of Practice’, (Consoli et al.)• 1997-2000, ISO publishes Standards 14040-43, defining the different LCA stages• 1998-2001, ISO publishes Standards and Technical Reports 14047-49• 2000, UNEP and SETAC create Life Cycle Initiative

Life Cycle Assessment Framework

Goal and scopedefinition

(ISO 14040)

Inventoryanalysis

(ISO 14041)

Impactassessment(ISO 14042)

Interpretation(ISO 14043)

Direct application:• product development and improvement• Strategic planning• Public policy making• Marketing • Other

Step 1 - Goal and Scope Definition It is important to establish beforehand what purpose the model

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

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

Thus, pay special attention to: Basis for evaluation (what and why) Temporal boundaries (time scale) Spatial boundaries (geographic)

Goal and Scope DefinitionExample for Goal Definition:Example for Goal Definition:

The goal of the LCA is to identify options for improving the environmental performance of the material polyethylene in disposable bread bags. The results of this LCA will be used for product and process development. The plastic bag manufacturer wants to be able to analyze the effects of changes in its processes, in terms of technology, inputs, and products composition, on the total environmental impact. This information, in turn, can be used to prioritize measures that can be taken to improve the environmental performance. This LCA does not aim at a public comparative assertion.

The study is conducted by Pro-Duct Consultancy Ltd, a medium-sized private engineering bureau. The commissioner is Bag-Away, a large producer of plastic disposable bags. Interested parties are mainly the plastics industry, bakeries and shops. A steering committee with representatives of the producer, the ministry of the environment and academia will be formed. Finally, an expert review will be carried out at NILCAR, the National Institute for LCA Research.

Goal and Scope DefinitionExample for Scope Definition:Example for Scope Definition:

A simplified LCA is carried out to compare three different end-of-life management options, namely landfill, recycling and reuse, for structural steel sections in the UK construction sector. The study and its data therefore intends to be representative of the current practices and technologies in the UK construction sector.

Initially, the only environmental intervention covered will be the energy requirementsof all processes, since this has shown to be an important environmental indicator for the construction industry, and the environmental impact of main interest is climate change.

The total size of the study is 8 person-months. A large portion of this time will be devoted to the studying and modeling of the product system, and the collection ofrepresentative data for the most important processes in production, use and end-of-life management.

What are functional units for the comparison of

Various paints?

Paper versus plastic bags in supermarkets?

20m2 of wall covering with a colored surface of 98% opacity and a lifetime of 5 yrs

Comfortable carrying of X kg and Y m3 of groceries

Goal and Scope DefinitionBe specific about the unit of analysis!

Step 2 - Inventory Analysis This means that the inputs and outputs of all life-cycle

processes have to be determined in terms of material and energy.

Start with making a process tree or a flow-chart classifying the events in a product’s life-cycle which are to be considered in the LCA, plus their interrelations.

Next, start collecting the relevant data for each event: the emissions from each process and the resources (back to raw materials) used.

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

Single Stage Flow Diagram The following diagram contains inputs and outputs to

be quantified in a single stage or unit operation see EPA Life-Cycle Design Guidance Manual, EPA Report

no. EPA/600/R-92/226, page 104

Single Stage or Unit Operation

Energy

Waste

Primary Product

Product Material Inputs (including reuse & recycle from another stage)

Reuse/ Recycle

Reuse/ Recycle

Useful Co-productFugitive & Untreated Waste

Process Materials, Reagents, Solvents & Catalysts (including reuse & recycle from another stage)

Example: Simplified Process Tree for a Coffee Machine’s Life-Cycle

assembly

poly- aluminium

extrusion

+ transport

disposal inmunicipalwaste

disposal of

in org. waste

use

paper

duction filter pro-

sheet steel

stampingforming

glas

forming

filters + coffee

coffee

roasting

packaging

water

injectionmoulding

bean styrene

electricity

assembly

poly- aluminium

extrusion

+ transport

disposal inmunicipalwaste

electricity

disposal of

in org. waste

use

paper

duction filter pro-

sheet steel

stampingforming

glas

forming

filters + coffee

coffee

roasting

packaging

water

injectionmoulding

bean styrene

7.3 kg 1 kg 0.1 kg 0.3 kg 0.4 kg

375 kWh

White boxes are not included in assessment/inventory

Example: Simplified Process Tree for a Coffee Machine’s Life-Cycle

Problems with Inventory Analysis The inventory phase usually takes a great deal of time and

effort and mistakes are easily made.

Allocation is an issue.

There exists published data on impacts of different materials (http://www.nrel.gov/lci/, http://www.ecoinvent.ch/, http://www.globalspine.com/, http://lca-net.com/spold/) However, the data is often inconsistent and not directly applicable due

to different goals and scope. It is expected that both the quantity and quality of data will improve in

the future.

Results are generalized improperly.

Step 3 - Impact Assessment The impact assessment focuses on characterizing the type

and severity of environmental impact more specifically.

Life Cycle Inventory results

Impact categories

Category indicator results

Environmental profile

Weighting

One-dimensional environmental score

Normalization

Characterization

Classification ISO 14042mandatory

ISO 14042optional

SO2

emissions

Acidrain

Acidifiedlake

Deadfish

Loss ofbiodiversity

Source Midpoint Endpoint

CFCemissions

Tropospheric OD

Stratospheric OD

UVBexposure

Humanhealth

A category indicatorcategory indicator, representing the amount of impact potential, can be located at any place between the LCI results and the category endpoints. There are currently two main Impact Assessment methods:

• Problem oriented IA methods stop quantitative modeling before the end of the impact pathway and link LCI results to so-defined midpoint categories (or environmental problems), like acidification and ozone depletion.

• Damage oriented IA methods, which model the cause-effect chain up to the endpoints or environmental damages, link LCI results to endpoint categories.

Impact categories

Human toxicity

Photochemical oxidant formation

Ozone depletion

Climate change

Acidification

Eutrophication

Ecotoxicity

Land use impacts

Species & organism dispersal

Abiotic resources depletion

Biotic resources depletion

LCIresults

Human Health

Biotic & abioticnatural environment

Biotic & abioticnatural resources

Biotic & abioticmanmade resources

Midpoint categories(environmental problems)

Endpoint categories(environmental damages)

Source: Int J of LCA 9(6) 2004

Impact categories proposed by UNEP/SETAC Life Cycle Initiative in 2003

LCI results

LCI results assigned toImpact category

Category indicator results

Category endpoint

Impact category

Example:

Acidification

Proton release(H+ aq)

Cd, CO2, NOX, SO2, etc.(kg/functional unit)

Acidifying emissionsNOX, SO2, etc.

(kg/functional unit)

In general:

- Forests- Fish populations- etc.

Characterization model

Source: ISO14042

Classification and characterization - Example

Impact category AcidificationLCI results Emissions of acidifying substances to the air (in kg)Characterization model RAINS10 model, developed by IIASA, describing the fate

and deposition of acidifying substances, adapted to LCACategory indicator Deposition/acidification critical loadCharacterization factor Acidification potential (AP) for each acidifying emission to

the air (in kg SO2 equivalents/kg emission)Unit of indicator result kg SO2 eq

Substance AP (in kg SO2 equivalents/kg emission)ammonia 1.88hydrogen chloride 0.88hydrogen fluoride 1.60hydrogen sulfide 1.88nitric acid 0.51Nitrogen dioxide 0.70Nitrogen monoxide 1.07Sulfur dioxide 1.00Sulphuric acid 0.65

Source: (Guinée et al., 2002)

Classification and characterization – Example

Plastic versus Paper Bag Classification

The paper bag causes more winter smog and acidification, but scores better on the other environmental effects.

The classification does not reveal which is the better bag. What is missing is the mutual weighting of the effects.

Classification / Characterisation

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

greenhouseeffect

ozone layerdepletionacidification

eutrophicationheavy metals carcinogens winter smog

summer smog

pesticides

Paper bag

LDPE bag

A Single Impact Figure Goal: Develop a single figure for comparison

purposes Several methods exist, but it is still a

controversial issue and no singular widely accepted method exists.

Three well-documented and used methods are: The Eco-Points method The Environmental Priority System The Eco-Indicator

Eco-Points Method The eco-points method was developed in Switzerland and is

based on the use of national government policy objectives. The evaluation principle is the distance to target principle, or

the difference between the total impact in a specific area and the target value. The target values in the original Ecopunkten method were derived

from target values of the Swiss government. There is a Dutch variant.

The use of policy objectives is controversial given that a policy does not express the true seriousness of a problem. Various political, economic, and social considerations also play a

role when formulating these objectives.

The Environmental Priority System

The EPS system was used first for Volvo in Sweden. It is not based on governmental policy, but on

estimated financial consequences of environmental problems.

It attempts to translate environmental impact into a sort of social expenditure. The first step is to establish the damage caused to a number

of “safeguard objects” - objects that a community considers valuable.

The next step is to identify how much the community is prepared to pay for these things, i.e., the social costs of the safeguard objects are established.

The resulting costs are added up to a single figure.

The Eco-Indicator (95 and 99) The Eco-Indicator 95 was developed in a joint project carried out by

companies, research institutes and the Dutch government. Aim: develop an easy-to-use tool for product designers Outcome: A list of 100 indicators for the most significant materials

and processes. By using these indicators a designer can easily make combinations and

carry out his/her own LCA. No outside expert or software are needed. Indicators have been drawn up for all life-cycle phases

the production of materials such as steel, aluminum, thermo-plastics, paper, glass

production processes, such as injection molding, rolling, turning, welding transport by road, rail, and sea energy generating processes waste processing processes, such as incineration, dumping, recycling.

The most recent revised version is called Eco-Indicator 99.

Life Cycle Assessment Framework

Goal and scopedefinition

(ISO 14040)

Inventoryanalysis

(ISO 14041)

Impactassessment(ISO 14042)

Interpretation(ISO 14043)

Direct application:• product development and improvement• Strategic planning• Public policy making• Marketing • Other

Case: Disposable versus reusable diapers

Background:

• P&G launched Pampers disposable diapers in the 1960s.

• By the early 1990s, Pampers contributed over 18% to annual revenues.

• Became symbol of the ‘throw-away’ society and was targeted by NGOs.

• P&G commissioned Arthur D. Little in 1990 to conduct an LCA

The Life Cycle Analysis:

Arthur D. Little made the following simplifying assumptions among others:

• The number of daily diaper changes is the same for both types of diapers.

• 90% of all reusable diapers are laundered at home.

Response:

• As a response to the results, Greenpeace commissioned its own LCA.

Results from Study A

0

20

40

60

80

100

120

140

160

Rawmaterials

(lbs)

Energy(1000Btu)

Water (gal) Emissionsto Air

(lbs/100)

Wastewater

effluents(lbs/100)

Processwaste (lbs)

Post-consumer

waste (lbs)

Disposable

Reusable

Functional unit: Weekly diaper needsFunctional unit: Weekly diaper needs

Case: Disposable versus reusable diapers

Results from Study B

0

5

10

15

20

25

30

Rawmaterials

(lbs)

Energy(10,000Btu)

Water(10gal)

Emissions to Air

(lbs/10)

Waste watereffluents(lbs/100)

Processwaste (lbs)

Post-consumer

waste (lbs)

Disposable

Reusable

Functional unit: Weekly diaper needsFunctional unit: Weekly diaper needs

Case: Disposable versus reusable diapers

Which study do you attribute to each organization?

What do you think now about disposable vs. reusable diapers?

Case: Disposable versus reusable diapers

The Arthur D. Little study was only one of many LCAs that were performed to compare disposable and reusable diapers.

Their conflicting results due to different inventory data, model assumptions, boundary choices and calculation methods have prevented a generally accepted conclusion.

This graph compares from two different sources, Allen et al. (1992) which report data from a Franklin Associates Study (1992) and the World Resources Institute (WRI, 1994) which reports data from the Arthur D. Little study (1990):

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Energy(million Btu)

Water (1000 gal)

Enissions toair (lbs)

Emission towater (lbs)

Solid waste(cubic feet/

lbs)

ALLEN DATA Disposable

WRI DATA Disposable

ALLEN DATA Reusable (10/90)

WRI DATA Reusable (10/90)

Case: Disposable versus reusable diapers

Case: Disposable versus reusable diapers

The data from Allen et al. is almost consistently higher than the data from the WRI, up to a factor of 6.

The ratios between disposable and reusable diaper data is consistently smaller in the Allen et al. data compared to the WRI data.

However, the general directions of the results are identical: Reusable diapers

consume more energy and more water Consume less raw materials Generate more emissions to air and water Generate less waste

Who are the users?

What are the uses?

LCA:• Goal & Scope• Life Cycle Inventory• Impact Assessment• Interpretation

The Use of LCA

• Companies: Especially in Scandinavian countries, Japan, Holland, Germany, Switzerland (e.g. Volvo, Electrolux, Honda, Toyota, Proctor & Gamble, Unilever, Corus, Arcelor, Alcan, etc.) Through in-house experts, LCA consultancies or universities.

• NGOs: Mostly commissioned to external LCA consultancies or universities.

• Trade associations: Especially for material commodities (e.g. plastics, steel, aluminum, concrete, etc.) Through the experts of their member companies, LCA consultancies or universities.

• Government agencies: Especially in Scandinavian countries, Japan, Holland, Germany, Switzerland, EU Through in-house experts, LCA consultancies or universities.

• Business analysts: Typically analyze externally created LCA information on business and sectors.

Users of LCA

• NGOs: To create scientific foundations of campaigns or investigate claims by industry

• Companies: Originally intended for external use, e.g. marketing. However, currently mainly for internal use due to bad initial experiences of external uses. Currently mainly retrospective and for learning proposes, instead of prospective use for decision making purposes. Currently, decisions based on LCA results are more operational than strategic.

• Trade associations: Trade associations of material commodities producers more frequently use LCA for external purposes (e.g. marketing, policy process).

• Government agencies: To analyze and design environmental policies and regulations (especially by the EPAs of European countries). EUs Integrated Product Policy recommends LCA.

• Business analysts: To analyze and forecast trends of individual companies and industry sectors.

Uses of LCA

Most companies currently use LCA for internal purposes.

Internal uses are:

• Hotspot analysis of existing or planed products

• Compare existing products with products under development

• Product/process design (short-term, operational)

• Product/process development (long-term, strategic)

As LCA methodology matures, so do the number & scope of external uses.

External uses are:

• Marketing, especially final product comparisons (credibility)

• Lobbying, especially commodity comparisons

• Providing information and education to customers and other stakeholders

• Eco-labeling (also called environmental product declarations – EPDs)

Internal vs. External Use

Issues with LCA Complex and a lot of effort is required Life Cycle Analyses have problems and are difficult

to use: What is the functional unit? What if your process does not match the unit process in

the LCA database? Impact categorization is difficult No national/worldwide standardized system

Without common methodology LCA results are very difficult to reproduce

Need to do LCA for every product in company

Issues with LCA Designers and manufacturing engineers find it almost

impossible to practically work with LCAs because of the consistent lack of solid data about all aspects of a products

life cycle, the nearly infinite amount of decisions to make and data to deal

with, the lack of standardization resulting in numerous conversions

and interpretations, the lack of a standard evaluation scheme caused by and

resulting in different views on what is environmentally correct, the approach is currently only suitable for design analysis /

evaluation rather than design synthesis. LCAs are "static" and only deal with a snapshot of material and energy inputs and outputs in a dynamic system.

Value of LCA

Many environmental choices are about trade-offs between different types of burdens

Without impact assessment these burdens are very difficult to compare

LCA methodology has come a long way since the early 1990s