Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Exploring the relevance of uncertainty in the life cycle assessment of forest products
Umeå University, Faculty of Science and Technology, Department of Chemistry. SP Technical Research Institute of Sweden.
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The role of forest biomass as a replacement for fossil fuels and products is becoming increasingly prominent as a means to mitigate climate change. To guide a sustainable transition towards a forest-based bio-economy, it is important that advantages and disadvantages of forest products are assessed, to ensure that the products deliver environmental impact reduction. Life Cycle Assessment (LCA) has become heavily relied upon for assessing the environmental impact of bio-based products. However, LCAs of similar product systems can lead to results that differ considerably, and the method is, thus, associated with uncertainties. It is, therefore, necessary to explore the relevance of uncertainties, to build knowledge about enablers and challenges in using LCA for assessing forest products.

Three important challenges in the context of uncertainty in LCA are the focus of this thesis: 1) system boundaries, 2) climate impact assessment practice, and 3) allocation. More specifically, the relevance of a) including and excluding life cycle phases, b) potentially important climate aspects, and c) applying different allocation methods, was assessed. Case studies involved a chemical industry cluster, a biorefinery, and single product value chains for a plastic box, a fuel, and a building.

In summary, the thesis demonstrates that:

  • A major share of the environmental impact related to the production of an industry cluster can occur outside the cluster gates, so when strategies involving a transition to forest biomass feedstock are developed and evaluated, a life cycle perspective reveals the full environmental impact reduction potential.
  • For bio-based products differing in functional properties from the fossil products they are meant to replace, material deterioration in the use phase can contribute substantially to overall environmental performance. This is acknowledged if all life cycle phases are regarded.
  • As climate aspects commonly not assessed in forest product LCAs could influence results greatly, and even affect the outcome of comparisons between forest and non-forest products, the climate impact of forest products is uncertain. It is, therefore, important that this uncertainty is acknowledged and communicated, and that appropriate methods and guidelines are developed.
  • The choice of allocation method in the LCA of biorefinery products can have a major influence on results, especially for physically non-dominant products and in consequential studies. In these cases, scenario analysis is especially valuable to show the possible range of results.

LCA provides useful guidance for forest product development and production as the life cycle approach reveals causes of environmental impact throughout the product value chain. Proper identification, estimation, and management of uncertainties strengthen the provision of reliable decision support.

Abstract [sv]

Att ersätta fossila bränslen och produkter med skogsbiomassa blir ett allt viktigare sätt att försöka minska klimatförändringen. För att säkerställa en hållbar övergång till en skogsbaserad bioekonomi är det viktigt att fördelarna och nackdelarna med skogsprodukter bedöms, för att klargöra att de faktiskt ger minskad miljöpåverkan. Livscykelanalys (LCA) är en flitigt använd metod för att bedöma miljöpåverkan från biobaserade produkter. Dock kan LCA:er på snarlika produktsystem komma fram till resultat som skiljer sig avsevärt. Metoden är således förknippad med osäkerheter. Det är därför nödvändigt att undersöka betydelsen av osäkerheter och därigenom bygga upp kunskap om förutsättningar för och utmaningar i användningen av LCA för bedömning av skogsprodukters miljöprestanda.

Avhandlingen fokuserar på tre viktiga utmaningar som alla rör osäkerheter i LCA: 1) systemgränser, 2) praxis vid bedömning av klimatpåverkan, och 3) allokering. Närmare bestämt bedöms betydelsen av a) inkluderandet och exkluderandet av livscykelfaser, b) potentiellt viktiga klimataspekter och c) olika allokeringsmetoder. Fallstudier har gjorts på ett kemiskt industrikluster, ett bioraffinaderi och produktvärdekedjorna för en plastlåda, ett fordonsbränsle samt en byggnad.

Sammanfattningsvis visar avhandlingen att:

  • En stor del av miljöpåverkan relaterad till ett industriklusters produktion kan uppstå utanför klustrets grindar. När strategier som innebär en övergång till skogsbasserat råmaterial utvecklas och utvärderas är det således viktigt att använda ett livscykelperspektiv, så att den fulla potentialen för minskad miljöpåverkan synliggörs.
  • För biobaserade produkter som skiljer sig i funktionella egenskaper från de fossila produkter de är avsedda att ersätta riskerar materialförsämring i användningsfasen att väsentligt minska den övergripande miljöprestandan. Om detta är fallet framgår tydligt om alla livscykelfaser beaktas.
  • Klimataspekter som vanligtvis inte bedöms i LCA-studier på skogsprodukter kan påverka resultatet kraftigt och även påverka resultatet av jämförelser mellan skogs och icke-skogsprodukter. Således är den faktiska klimatpåverkan av skogsprodukter osäker. Det är därför viktigt att osäkerheten uppmärksammas och kommuniceras samt att lämpliga metoder och riktlinjer för bedömning av klimatpåverkan från skogsprodukter utvecklas.
  • I LCA av bioraffinaderiprodukter kan val av allokeringsmetod ha en stor inverkan på resultaten. Detta gäller särskilt för fysiskt icke-dominanta produkter och i konsekvensanalyser. I dessa fall är scenarioanalys speciellt värdefullt att använda för att visa möjliga skillnader i resultat.

LCA ger värdefull vägledning för utveckling och produktion av skogsprodukter, då livscykeltänkandet beaktar orsakerna till miljöpåverkan i produkternas hela värdekedjor. Korrekt identifiering, uppskattning och hantering av osäkerheter stärker tillförlitligheten av beslutsunderlaget.

Place, publisher, year, edition, pages
Umeå: Umeå University , 2016. , 73 p.
Keyword [en]
LCA, wood, forestry, uncertainty, biorefinery, industrial symbiosis, allocation, system boundaries, bio-economy
Keyword [sv]
LCA, trä, skogsbruk, osäkerhet, bioraffinaderi, industriell symbios, allokering, systemgränser, bioekonomi
National Category
Environmental Sciences
Identifiers
URN: urn:nbn:se:umu:diva-118537ISBN: 978-91-7601-455-4 (print)OAI: oai:DiVA.org:umu-118537DiVA: diva2:915768
Public defence
2016-04-22, KB3B1, KBC-huset, 10:00 (English)
Opponent
Supervisors
Funder
Bio4Energy
Available from: 2016-04-01 Created: 2016-03-22 Last updated: 2016-04-20Bibliographically approved
List of papers
1. Life cycle perspective in environmental strategy development on the industry cluster level: a case study of five chemical companies
Open this publication in new window or tab >>Life cycle perspective in environmental strategy development on the industry cluster level: a case study of five chemical companies
2015 (English)In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 86, 125-131 p.Article in journal (Refereed) Published
Abstract [en]

The scale of industry clusters and their significant environmental impact make addressing environmental strategies on the cluster level an intriguing task. Although several studies indicate that upstream processes contribute significantly to the total environmental impact of the system, few studies assess how environmental strategy development can be approached from a life cycle perspective. The aim of this paper was to investigate the practical significance of life cycle-based environmental strategy development using a chemical industry cluster in Sweden as the case study. To assess the environmental impact, a cradle-to-gate life cycle assessment (LCA) was chosen as the method, with the total annual production of the cluster in 2011 as the functional unit. To cover the whole value chain, the global warming potential for downstream processes was also estimated. The findings were linked to the cluster vision, which aims to reduce environmental impact by 2030. The results indicate that the cluster must focus on the whole value chain when pursuing the aim of producing sustainable products as environmental impact both upstream and downstream of the cluster accounts for a larger share than on-site processes. The assessment also enables distribution of environmental impact among incoming material streams, thus providing the cluster with decision support when introducing renewable and recycled materials. Additionally, the assessment supports strategy comparison and serves as a base case against which strategy opportunities can be evaluated. This study demonstrates that the life cycle approach has interesting potential to support industry cluster companies in their mutual effort to improve environmental performance.

Keyword
LCA, Industry cluster, Chemicals, Industrial symbiosis, Environmental strategy
National Category
Chemical Sciences
Identifiers
urn:nbn:se:umu:diva-99780 (URN)10.1016/j.jclepro.2014.08.016 (DOI)000347501000015 ()
Available from: 2015-02-16 Created: 2015-02-12 Last updated: 2017-12-04Bibliographically approved
2. Environmental evaluation of industry cluster strategies with a life cycle perspective: replacing fossil feedstock with forest-based feedstock and increasing thermal energy integration
Open this publication in new window or tab >>Environmental evaluation of industry cluster strategies with a life cycle perspective: replacing fossil feedstock with forest-based feedstock and increasing thermal energy integration
2015 (English)In: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290Article in journal (Refereed) Submitted
National Category
Chemical Sciences
Identifiers
urn:nbn:se:umu:diva-118737 (URN)
Available from: 2016-03-31 Created: 2016-03-31 Last updated: 2017-11-30
3. Climate impact assessment in life cycle assessments of forest products: implications of method choice for results and decision making
Open this publication in new window or tab >>Climate impact assessment in life cycle assessments of forest products: implications of method choice for results and decision making
Show others...
2016 (English)In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 116, 90-99 p.Article in journal (Refereed) Published
Abstract [en]

As life cycle assessments are often conducted to provide decision support, it is important that impact assessment methodology is consistent with the intended decision context. The currently most used climate impact assessment metric, the global warming potential, and how it is applied in life cycle assessments, has for example been criticised for insufficiently accounting for carbon sequestration, carbon stored in long-lived products and timing of emission. The aim of this study is to evaluate how practitioners assess the climate impact of forest products and the implications of method choice for results and decision-making. To identify current common practices, we reviewed climate impact assessment practices in 101 life cycle assessments of forest products. We then applied identified common practices in case studies comparing the climate impact of a forest-based and a non-forest-based fuel and building, respectively, and compared the outcomes with outcomes of applying alternative, non-established practices. Results indicate that current common practices exclude most of the dynamic features of carbon uptake and storage as well as the climate impact from indirect land use change, aerosols and changed albedo. The case studies demonstrate that the inclusion of such aspects could influence results considerably, both positively and negatively. Ignoring aspects could thus have important implications for the decision support. The product life cycle stages with greatest climate impact reduction potential might not be identified, product comparisons might favour the less preferable product and policy instruments might support the development and use of inefficient climate impact reduction strategies.

Keyword
LCA, Wood, Global warming, Carbon, Fuel, Building
National Category
Environmental Sciences
Identifiers
urn:nbn:se:umu:diva-118735 (URN)10.1016/j.jclepro.2016.01.009 (DOI)000370885800010 ()
Available from: 2016-03-31 Created: 2016-03-31 Last updated: 2017-11-30Bibliographically approved
4. Allocation in LCAs of biorefinery products: implications for results and decision-making
Open this publication in new window or tab >>Allocation in LCAs of biorefinery products: implications for results and decision-making
Show others...
2015 (English)In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 93, 213-221 p.Article in journal (Refereed) Published
Abstract [en]

Abstract In Life Cycle Assessments (LCAs) of biorefinery products, a common challenge is the choice of method for allocating environmental burdens of multifunctional processes (feedstock cultivation and biorefinery processes), a choice which can substantially influence LCA results and hence decision-making. The aim of this paper is to explore how this choice influences results and in which decision contexts the choice is particularly important. To do this, we tested six allocation methods in a case study of a biorefinery using pulpwood as feedstock. Tested methods included: main product bears all burden, substitution, traditional partitioning methods (based on economic value and exergy), a hybrid method combining elements of substitution and partitioning, and an alternative hybrid method developed by us, which allocates less environmental burden to co-products with a high potential to mitigate environmental burdens. The methods were tested in relation to decision contexts and LCA questions of relevance for biorefineries. The results indicate that the choice of allocation method deserves careful attention, particularly in consequential studies and in studies focussed on co-products representing relatively small flows. Furthermore, the alternative hybrid allocation method is based on a logical rationale – favouring products with higher substitution potential – and has some other potential benefits. However, in cases where the scales of co-product flows are of different orders of magnitude, the method yields extreme results that could be difficult to interpret. Results also show that it can be important with consistent allocation for both cultivation and biorefinery processes, particularly when substitution is applied.

Place, publisher, year, edition, pages
Elsevier, 2015
Keyword
Life cycle assessment, Multifunctional, Forest, Forestry, Bio-based, Hybrid allocation
National Category
Organic Chemistry
Identifiers
urn:nbn:se:umu:diva-100342 (URN)10.1016/j.jclepro.2015.01.013 (DOI)000353095100024 ()
Available from: 2015-03-01 Created: 2015-03-01 Last updated: 2017-12-04Bibliographically approved
5. The importance of including service life in the climate impact comparison of bioplastics and fossil-based plastics
Open this publication in new window or tab >>The importance of including service life in the climate impact comparison of bioplastics and fossil-based plastics
2016 (English)In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502Article in journal (Refereed) Submitted
National Category
Chemical Sciences
Identifiers
urn:nbn:se:umu:diva-118738 (URN)
Available from: 2016-03-31 Created: 2016-03-31 Last updated: 2017-11-30

Open Access in DiVA

fulltext(1242 kB)224 downloads
File information
File name FULLTEXT01.pdfFile size 1242 kBChecksum SHA-512
bedb4c34acb07c63de0d119a2f3dbccb83db05484bc9030b7a6e4e68c438d619931c4e3dba262811c6339c8005a1640d0d3bb794d535399f4837994e0fad8385
Type fulltextMimetype application/pdf
spikblad(57 kB)18 downloads
File information
File name SPIKBLAD01.pdfFile size 57 kBChecksum SHA-512
753f32dc3aede8bdde80d75cd68d1a51ea755708fdd2f13d82a0169c701a117461ca3dcc85dab3187f2b5f2aa21283e923652a1a7c4a15056c9841bd3c955fb4
Type spikbladMimetype application/pdf

Authority records BETA

Røyne, Frida

Search in DiVA

By author/editor
Røyne, Frida
By organisation
Department of Chemistry
Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 224 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 1781 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf