Because life-cycle analysis provides a holistic account of the environmen-tal impacts of a product throughout its life, it is a very powerful aid to decision-making. By its nature, it is also a very inclusive technique, with scope for major stakeholders to be involved in planning the study and interpretation of its results. It is suited for application to contro-versial cases, where environmental benefits and disbenefits of a product are strongly debated, or where the relative merits of alternative pro-ducts need to be evaluated.

It should be used sparingly. Large amounts of information need to be processed by a multidisciplinary team. The amount of effort required

and the level of expertise of the resear-chers will need to be correspondingly high, leading to high costs. For simi-lar reasons it is not a rapid technique, and is unsuitable when fast answers are needed.

Life-cycle analysis can be applied to any system that has impact on the environment. It can be used to assess manufactured products, from nano-scale electronics to buildings and beyond. It is applicable to industrial, agricultural or waste disposal proces-ses, the provision of energy or other utilities, environmental protection measures, services, transport modes, and so on. The term “product” used in this leaflet can be interpreted very broadly.

O n e Wo r l d , D o n’ t Wa s t e I t

When to use life-cycle analysis

Stakeholder consultation

Consulting stakeholders is anintegralcomponentoflife-cycleanalysis.Itservestwopurposes:it maximises the amount of in-formationabouttheproductandits impacts that is available tothestudy;anditincreasestrans-parency, improvingthechancesthatstakeholderswillaccepttheresults of the study. This latterreasonisparticularlyimportantincontroversialcases.

Thereareseveralwaystoconsult,and the choice of methodologywilldependon thenatureof theissue and the relevant stakehol-ders.Amethodthathasbeenusedsuccessfullyistoholdaseriesofopen workshops, typically oneat the start of the study, one toannounce the results and one or

moreasthestudyisprogressing.The early workshop allows sta-keholders to influence the design of thestudy,and inparticular toparticipateinsettingthebounda-ries.Intermediateworkshopswillpresentemergingresultsandseekviewsonwhether,inthelightofthoseresults,thestudyplanneedstobeamended.Finallytheresultsshouldbeannouncedataworks-hop where their significance can bediscussedwithstakeholders.

w w w. b a s e l . i n t

Stocksoftoxicwaste-PhotoStillpictures

Boundaries

Settingtheboundariesorscopeoftheanalysisisacriticalandearly step. The objective is tolimitthestudyinawaythatba-lancestheneedforpracticalityintermsofsizeandcostagainstthe importance of capturingsufficient of the product’s im-pacts. A fully holistic studywouldnotbefeasible–societalactivities, especially industrialactivities, are too interconnec-tedforsimpleboundariestobedrawnaroundasingleproductwithoutsomelossofprecision.Carefulselectionofboundaries

will reduce the inaccuracy toinsignificance.

For example, in a full life-cycleanalysisof aproductmade frommetal, the upstream limit mightbe the extraction of metal ore.Typically,theenergyrequiredforthis extraction and the damagecausedtotheenvironmentbytheminingoperationwouldbeinclu-ded in the environmental costs,but environmental impacts asso-ciated with the construction anddisposaloftheminingequipmentwould be excluded. Thus in this

O n e Wo r l d , D o n’ t Wa s t e I t

A sse s s ing the impac t s

The assessment of environmen-tal impacts for the purposes of alife-cycle analysis involves com-pilinganinventoryofenergyandmaterial inputsand releases,eva-luatingtheenvironmentalimpactsassociated with identified inputs and releases, and interpreting theresults. This process must spaneachstageofthelife-cycleoftheproduct within the scope of theanalysis.

Theimpactsfromproduction,useanddisposal are likely to be suf-ficiently different to require sepa-rate analyses. A range of scientific and technical expertise will needto be applied to the study andthis implies the establishment ofan interdisciplinary team. life-cycle analysis is not a techniquefor non-professionals, but it doesreadilylenditselftocollaborativeendeavour.

In drawing up the inventory ofimpacts, input from stakeholderswill be valuable to capture thoseeffectsthattheexpertshaveover-looked.Impactsmaythenusefullybegroupedintocategoriessuchas,forexample:depletionofnon-re-newablerawmaterials; landscapedamage;toxicreleases;impactsoftransportandenergyuse;andwas-te disposal impacts. Finally, theirimplicationsintermsofscaleandnatureareanalysed–thisisastepthat will normally be carried outby experts in the particular typeofimpacts:forexample,environ-mental chemistry and toxicology

toassess the impacts fromhazar-doussubstances.

Someimpactswillbeofmarginalrelevance, for example becausethey are small or because theyspan the boundary of the study,and in these cases executive de-cisions, informed by stakehol-der opinion, will be needed onwhether or not to include them.It will always be important to berobust, even against stakeholderopinion, where the inclusion ofa marginal impact would have adisproportionateeffectonthecostoftheproject,andhereapolicyoftransparency will be particularlyvaluableindefendingtheintegrityofthestudy.

It is important to recall that pro-ductscanhavepositive,aswellasnegative impacts on the environ-ment,andallshouldbetakeninto

example the boundary has beenset between the immediate envi-ronmentalcostsoftheproductun-der study and the environmentalcostsofassociatedproducts.

InthecontextoftheBaselConven-tion,alimitedlife-cycleanalysismighthaveanupperboundaryatthepointwhere theproductbeco-mes waste. Depending on the is-suesbeingaddressedbythestudy,a strict adherence to the legal defi-nitionofwastewouldnotbeneces-sary.Also the term “product” canbe used flexibly to meet the needs of the study. For example, life-cycle analysis techniques havebeenusedtocomparetherelativeenvironmental costs of landfilling

andincineratingmunicipalwastes.Here,theupperboundarywaschosenas thepointatwhich thewastestreamsdiverged–headingeither to the landfill or to the in-cinerator–andthe“products”un-deranalysiswerethetwodisposaloptions.

Thepositionoftheboundariesde-fines what is included in the study and what is excluded. It can, the-refore,affecttheresultinganalysisconsiderably, and could becomecontroversial. Take, for example,aproductmadefromPVC.Shouldthe environmental impacts of themercury used in chlorine produc-tionplantsbetakenintoaccount?

Thatisadecisionthatdependsonthe reason for which the study isbeing carried out, but will inevi-tablygiverisetocontroversyandmay well need a political deci-sion.Settingboundariesisoneofthekey aspects of any life-cycleanalysis on which stakeholderconsultationisessential.

w w w. b a s e l . i n t

Pilesofusedbatteries-PhotoSBC

For some purposes, a detailed sta-tement of the impacts of the pro-duct over the scope of the study will be sufficient. More usually, though, an element of quantifica-tion will be required. For exam-ple, a qualitative life-cycle analy-sis comparing one-trip packaging with a re-usable alternative will be able to describe the impacts of both but will not be able to show which has the lower impact on the environment. A package made of glass, which is returned, cleaned and re-used 100 times during its life, may show much lower im-pacts in terms of raw material usage and volume of waste gene-rated than its one-trip plastic al-

ternative, but much higher energy and transport impacts. Where does the balance lie? Only through an element of quantification may we start to answer this.

In a quantitative study, the impacts will need to be evaluated, converted into common units and normalised to a standard output. For example: if the product is an item with finite life the impacts might be normalised to a product-year; for re-usable items the impacts per use might be appro-priate; for a fuel, the impacts per unit of energy output could be used.

Economic currency units are often chosen as the medium for quantifi-

O n e Wo r l d , D o n’ t Wa s t e I t

Quantifying the impacts

cation. This has the advantage that many environmental impacts have a real or hypothetical economic cost associated with them that can be used directly. For example, to quan-tify pollution of potable water, the cost of cleaning the water supply to a suitable quality can be used as a measure of the impact. Where the threat is to natural resources such as wildlife or landscape, the cost of pro-tecting the resource might be used.

In situations where such costs are not available, for example because there is no feasible method of pro-tecting a natural resource or the damage has already been incurred, then some monetary value has to be placed on the resource. This is difficult and controversial, though techniques do exists and for this sort of exercise it will be necessary to include expertise in environmen-tal economics on the study team.

The use of monetary units in this way has the further advantage of

making the results more accessi-ble to non-technical stakeholders. However there is a disadvantage at the policy-making stage. A life-cycle analysis that expresses its result in terms of money can easily be mis-taken for cost-benefit analysis, but cost-benefit analyses are not always appropriate in this context. This is because the economic benefits of a product are not always fully ac-crued to those who suffer the envi-ronmental costs, and there could be serious issues of environmental jus-tice that would need somehow to be taken into account. It is important always to emphasise the disjunction between beneficiaries and the disad-vantaged in presenting results in mo-netary terms.

This problem could be avoided if other units were used. For some stu-dies, for example, energy units might provide better media for compari-son. But usually the disadvantages of using currency units are outweighed by the advantages.

account.Forexample,inalife-cy-cleanalysisofcoppicedwoodusedasafuel,thevalueofacoppiceasa wildlife refuge would offset tosomeextent thenegative impactssuchaswateruseand transporta-

tion costs. For some purposes, itmightalsobevaluabletotakeac-countofthepositiveandnegativesocietalimpactsoftheproduct.Insuch cases a strong stakeholderinputisneeded.

w w w. b a s e l . i n t

A life-cycle analysis study will normally require diverse expertise, stakeholder involvement, resources and time, and this can be a serious barrier to widespread adoption of the technique. The answer may be through the formation of partnerships. Many products are traded inter-nationally, and there is, consequently, scope for international colla-boration in this sort of study. Not all of the identified impacts will be relevant in all regions but in many cases there will be sufficient commonality to justify a multinational approach.

A central resource, to facilitate the identification of potential partners and serve as a clearinghouse for studies and the dissemination of their results, would stimulate such international cooperation. As yet, such a facility does not exist.

Scope for cooperation