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Sökning: WFRF:(Ekvall Tomas) > Engelska

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1.
  • Brandao, Miguel, et al. (författare)
  • RED, PEF, and EPD: Conflicting rules for determining the carbon footprint of biofuels give unclear signals to fuel producers and customers
  • 2022
  • Ingår i: Frontiers in Climate. - : Frontiers Media SA. - 2624-9553. ; 4
  • Tidskriftsartikel (refereegranskat)abstract
    • Biofuel producers and other commodity suppliers are increasingly affected by conflicting rules for life cycle assessment (LCA). They may get multiple requests for LCAs to be used in various contexts, which require the application of different methodological approaches that vary in scope, system boundaries, data demand, and more. This results in increased cost and competence requirements for producers, as well as confusion among other actors including their customers. Differences in methodologies might also lead to various outcomes, conclusions and conflicting guidance regarding which fuels to prioritize or develop. We have analyzed the actual differences when applying three different frameworks: the EU Renewable Energy Directive (RED), the EU framework for Product Environmental Footprints (PEF), and the framework of Environmental Product Declarations (EPD), which have different modeling requirements. We analyzed the methods from a conceptual point of view and also applied the methods to estimate the carbon footprint on a wide range of biofuel production pathways: (i) ethanol from corn, (ii) fatty acid methyl ester (FAME) from rapeseed oil, (iii) biogas from food waste, (iv) hydrogenated vegetable oil (HVO) from rapeseed oil, and (v) HVO from used cooking oil. Results obtained for a specific fuel could differ substantially depending on the framework applied and the assumptions and interpretations made when applying the different frameworks. Particularly, the results are very sensitive to the modeling of waste management when biofuel is produced from waste. Our results indicate a much higher climate impact for, e.g., biogas and HVO produced from used cooking oil when assessed with the PEF framework compared to the other frameworks. This is because PEF assigns at least part of the production of primary materials and energy to the use of recycled material and recovered energy. Developing Category Rules for biofuels for PEF and EPD ought to help clarifying remaining ambiguities.
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2.
  • Ekvall, Tomas, et al. (författare)
  • Attributional and consequential LCA in the ILCD handbook
  • 2016
  • Ingår i: The International Journal of Life Cycle Assessment. - : Springer. - 0948-3349 .- 1614-7502. ; 21:3, s. 293-296
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • This discussion article aims to highlight two problematic aspects in the International Reference Life Cycle Data System (ILCD) Handbook: its guidance to the choice between attributional and consequential modeling and to the choice between average and marginal data as input to the life cycle inventory (LCI) analysis. We analyze the ILCD guidance by comparing different statements in the handbook with each other and with previous research in this area. We find that the ILCD handbook is internally inconsistent when it comes to recommendations on how to choose between attributional and consequential modeling. We also find that the handbook is inconsistent with much of previous research in this matter, and also in the recommendations on how to choose between average and marginal data in the LCI. Because of the inconsistencies in the ILCD handbook, we recommend that the handbook be revised.
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3.
  • Ekvall, Tomas, 1963, et al. (författare)
  • Incentives for recycling and incineration in LCA: Polymers in Product Environmental Footprints
  • 2021
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • For material recycling to occur, waste material from a product life cycle must be made available for recycling and then used in the production of a new product. When recycling is beneficial for the environment, the LCA results should give incentives to collection for recycling and also to the use of recycled material in new products. However, most established methods for modelling recycling in LCA risk giving little or even wrong incentives. Many methods, such as the Circular Footprint Formula (CFF) in a Product Environmental Footprint (PEF), assign some of the environmental benefits of recycling to the product that uses recycled materials. This means that the incentive to send used products for recycling will be lower. If energy recovery also provides an environmental benefit, because the energy recovered substitutes energy supplied with a greater environmental impact, the LCA results may indicate that the waste should instead be sent to incineration – even when recycling is the environmentally preferable option for the society. This study aims to increase the knowledge on the extent to which PEF results, and LCA results in general, risk giving incorrect incentives for energy recovery from plastic waste. Our calculations focus on the climate impact of the recycling and incineration of LDPE waste generated in Sweden. Since this is a pilot study, we use easily available input data only. We estimate the net climate benefit through simple substitution, where recycled material is assumed to replace virgin material and where energy recovered from LDPE waste is assumed to replace average Swedish district heat and electricity. We then apply the CFF to find whether a PEF would give the same indications. Our results show no risk of a PEF or LCA giving incorrect climate incentives for incineration of fossil LDPE. However, an LCA can wrongly indicate that renewable LDPE should be incinerated rather than recycled. Our results indicate this can happen in a PEF when the heat and electricity substituted by incineration has 40-200% more climate impact than the Swedish average district heat and electricity. Our study also aims to increase knowledge about the extent to which correct incentives can be obtained through a more thorough analysis of incineration with energy recovery – specifically, through:     1. a deeper understanding of Factor B, which in the CFF can be used to assign part of the burdens and benefits of energy recovery to the energy instead of the product investigated, but which in the PEF guidelines by default is set to 0, or     2. a broader systems perspective that accounts for the effects of energy recovery on waste imports and thus waste management in other countries. We estimate Factor B based on the observation that waste incineration can be described as a process with multiple jointly determining functions. Waste treatment and energy recovery both contribute to driving investments in incineration. This, in turn, defines the volume of waste incinerated, the quantity of energy recovered, and the quantity of energy substituted. We propose that expected revenues from gate fees and energy are an appropriate basis for calculating Factor B. Up-to-date estimates of the expected revenues in the relevant region should ideally be used for the calculations. Lacking such data,we suggest the value B=0.6 can be used in the CFF when modelling waste incineration in Sweden. Our PEF calculations with Factor B=0.6 indicate such a PEF will identify the environmentally best option for plastic waste management in almost all cases. However, this is at least in part luck: Factor B will vary over time and between locations, and other parts of the CFF varies between materials. To account for the broader systems perspective, we develop two scenarios based on different assumptions on whether change in Swedish waste imports affects the incineration or landfilling in other European countries. The scenarios bring a large uncertainty into the results. This uncertainty is real in the sense that it is difficult to know how a change in Swedish waste imports in the end will affect waste management in other countries. The uncertainty still makes it difficult to draw conclusions on whether renewable LDPE should be recycled or incinerated. Our suggestions for Factor B and European scenarios both make the CFF more balanced and consistent: it now recognizes that not only recycling but alsoenergy recovery depends on more than the flow of waste from the life cycle investigated. However, neither Factor B nor the broader systems perspective amends the fact that LCA tends to focus on one product at a time. This might not be enough to guide a development that requires coordinated or concerted actions between actors in different life cycles – such as increased recycling or energy recovery. Assessing decisions in one product life cycle at a time might in this context be compared to independently assessing the action of clapping one hand. This will most probably not result in an applaud. Besides a more thorough assessment of energy recovery, we also discuss the option to give correct incentives for recycling from LCA by assigning the full environmental benefit of recycling to the product that generates waste for recycling but also to the product where the recycled material is used. We find that this 100/100 approach can give negative LCA results for products produced from recycled material and recycled to a high degree after recycling, because the benefits of recycling are counted twice. The LCA results would indicate that you save material resources by producing and recycling such products without ever using them. The 100/100 approach also lacks additivity, does not model foreseeable consequences, and does not assign a well-defined environmental value to the recovered secondary material. To guide concerted actions, like recycling or energy recovery, it seems systems analysis should ideally assess the necessary actions in combination. Many situations require the environmental impacts to be estimated for a specific product or a specific action. In some cases, however, the LCA results can be calculated and presented with, for example, the following introduction: “When the material is sent to recycling, you will, together with the recycler and the actor using the recycled material, jointly achieve this net environmental benefit: …” Such joint assessment of supply and demand for secondary materials means the allocation problem is avoided. It is also consistent with the recommendation in the old SETAC “Code of Practice” to assess life cycles with recycling by studying the inputs and outputs from the total linked system.
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4.
  • Ekvall, Tomas, 1963, et al. (författare)
  • Modelling incineration for more accurate comparisons to recycling in PEF and LCA
  • 2021
  • Ingår i: Waste Management. - : Elsevier BV. - 0956-053X .- 1879-2456. ; 136, s. 153-161
  • Tidskriftsartikel (refereegranskat)abstract
    • When recycling is beneficial for the environment, results from a life cycle assessment (LCA) should give incentives to collection for recycling and also to the use of recycled material in new products. Many approaches for modeling recycling in LCA assign part of the environmental benefits of recycling to the product where the recycled material is used. For example, the Circular Footprint Formula in the framework for Product Environmental Footprints (PEF) assigns less than 45% of the benefits of recycling to a polymer product sent to recycling. Our calculations indicate that this creates an incorrect climate incentive for incineration of renewable LDPE, when the recovered energy substitutes energy sources with 100–300% more climate impact than the Swedish average district heat and electricity. The risk of incorrect incentives can be reduced through allocating part of the net benefits of energy recovery to the life cycle where the energy is used; we propose this part can be 60% for Sweden, but probably less in countries without a district-heating network. Alternatively, the LCA can include the alternative treatment of waste that is displaced at the incinerator by waste from the investigated product. These solutions both make the LCA more balanced and consistent. The allocation factor 0.6 at incineration almost eliminates the risk of incorrect incentives in a PEF of renewable polymers. However, the focus of LCA on one product at a time might still make it insufficient to guide recycling, which requires concerted actions between actors in different life cycles.
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6.
  • Finnveden, Göran, et al. (författare)
  • Policy instruments towards a sustainable waste management
  • 2013
  • Ingår i: Sustainability. - Basel : MDPI AG. - 2071-1050. ; 5:3, s. 841-881
  • Tidskriftsartikel (refereegranskat)abstract
    • The aim of this paper is to suggest and discuss policy instruments that could lead towards a more sustainable waste management. The paper is based on evaluations from a large scale multi-disciplinary Swedish research program. The evaluations focus on environmental and economic impacts as well as social acceptance. The focus is on the Swedish waste management system but the results should be relevant also for other countries. Through the assessments and lessons learned during the research program we conclude that several policy instruments can be effective and possible to implement. Particularly, we put forward the following policy instruments: “Information”; “Compulsory recycling of recyclable materials”; “Weight-based waste fee in combination with information and developed recycling systems”; “Mandatory labeling of products containing hazardous chemicals”, “Advertisements on request only and other waste minimization measures”; and “Differentiated VAT and subsidies for some services”. Compulsory recycling of recyclable materials is the policy instrument that has the largest potential for decreasing the environmental impacts with the configurations studied here. The effects of the other policy instruments studied may be more limited and they typically need to be implemented in combination in order to have more significant impacts. Furthermore, policy makers need to take into account market and international aspects when implementing new instruments. In the more long term perspective, the above set of policy instruments may also need to be complemented with more transformational policy instruments that can significantly decrease the generation of waste.
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7.
  • Finnveden, Göran, et al. (författare)
  • Policy Instruments towards a sustainable waste management
  • 2016
  • Ingår i: Solid waste management: Policy and planning for a sustainable society. - : Apple Academic Press. - 9781771883740 - 9780429091650 ; , s. 185-246, s. 185-246
  • Bokkapitel (övrigt vetenskapligt/konstnärligt)
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8.
  • Hagberg, Linus, et al. (författare)
  • LCA calculations on Swedish wood pellet production chains - according to the Renewable Energy Directive
  • 2009
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • The study includes calculations of typical life cycle emissions of greenhouse gases for representative Swedish pellet production chains in accordance with the calculation rules in RED (Directive 2009/28/EC). The study also intends to analyse how the directive is applicable on solid biofuels in general and on wood pellet production in particular, and to identify such aspects of the methodology in RED that are associated with obscurities, problems or lead to misleading results compared to other life cycle analysis principles. The report includes a large number of alternative calculations to show how different facts, assumptions and methodological choices affect the results. This includes the effect of what fuels are used for drying, different transport distances, assumed fuel mix for purchased electricity, the variance in efficiency between the investigated plants as well as the effect of different interpretations of the RED methodology for greenhouse gas calculations.
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9.
  • Lindfors, Lars-Gunnar, et al. (författare)
  • The ILCD Handbook in a NUTSHELL - A brief analysis of the ILCD Handbook and the Draft Guidance on Product Environmental Footprint
  • 2012
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • ILCD står för International Reference Life Cycle Data System Handbook. Syftet med vår rapport är att beskriva uppkomsten och innehållet i ILCD-handboken och jämföra de rekommenderar som ges jämfört med god praxis inom livscykelanalys (LCA). Vi fångar också upp den första tillämpningen av handboken som är preliminära riktlinjer för "Environmental Footprints", och då speciellt "Product Environmental Footprints" (PEF). Riktlinjer för dessa Footprints finns i en preliminär "PEF Guide". Rapporten tar i första hand upp metodfrågor, krav och riktlinjer för miljöprofiler/footprints för produkter, men det finns även motsvarande riktlinjer för organisationer. ILCD-handboken är skriven för LCA-experter. För att branschföreningar, företag och myndigheter ska kunna utnyttja den här rapporten i sin pågående dialog med EU-kommissionen kring PEF-guiden har den skrivits för läsare som har en god kunskap eller åtminstone baskunskap om LCA-metodiken.
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10.
  • Poulikidou, Sofia, 1984, et al. (författare)
  • Impacts on fuel producers and customers of conflicting rules for life cycle assessment
  • 2022
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • The use of life cycle assessment (LCA) as a tool for estimating the environmental performance of a product or service in a holistic and systematic manner is increasing. Fuel producers may need to apply different methodological frameworks to be used in different contexts; internally for product development activities as well as externally for communication with customers or authorities. Different LCA frameworks may vary in scope, system boundaries (i.e. life cycle stages to be considered) or modelling requirements (such as data demands but also more detailed methodological features). They may also vary in terms of information they can provide in relation to the environmental performance of the product. Those variations could lead to conflicting outcomes and conclusions and may also increase complexity for the LCA practitioner leading to high competence and resource requirements. Within the research project: Impacts on fuel producers and customers of conflicting rules for LCA , the requirements of different LCA frameworks and their implications to fuel producers are investigated. Focus has been given on three specific frameworks that are identified as relevant or potentially relevant for fuel producers, namely: the recast of the EU Renewable Energy Directive (referred to here as RED II), the EU framework for Product Environmental Footprint (PEF), and the framework of Environmental Product Declaration (EPD). The aim of the project is to increase understanding on the different LCA frameworks available and identify whether the multitude of such frameworks gives conflicting recommendations for environmental improvements and fuel choices.   The three LCA frameworks listed above were applied in case studies. To illustrate the potential differences that the different frameworks may lead to, a variation of production pathways and feedstocks were selected including first generation as well as advanced biofuels. Based on the results obtained it can be concluded that applying all three frameworks is not a straightforward task. The methods contain fundamental differences and are at different levels of development, maturity, and adoption. In certain situations, they can lead to diverging conclusions as a result of different quantitative outcomes for a specific production pathway, thus influencing decision making processes in different directions. Understanding those differences and underlying assumptions is important for understanding the variations in outcome. The result for a specific fuel could differ substantially depending on the framework applied and the assumptions and interpretations made when applying this framework. Certain methodological parameters were identified to have a greater impact on the results than others: • The three frameworks diverge in the methods applied for modelling waste management, which can be very important for the results when the biofuel is produced from waste. • The frameworks diverge in what approaches are allowed for modelling processes with multiple products. This can be very important for the results when the fuel is co-produced with other products. • The frameworks also diverge in how the electricity supply is modelled. This is not very important for the results in most of our case studies, because the production of these biofuels does not require a lot of electricity. The study confirms that applying a framework like EPD or PEF in addition to RED II would require significant supplementary efforts. Not only because of different rules which were often contradicting or difficult to interpret but also because of additional data and reporting requirements. The need for expertise and resources is increasing for fuel producers to be able to provide EPD and PEF compliant assessments. To enhance the development and harmonization of LCA approaches this project stresses the need for product specific rules (in the form of Product Environmental Category Rules (PEFCR) and Product Category Rules (PCR)) for renewable fuels. Future versions of all three studied frameworks should be clearer on how specific methodological choices are to be applied (e.g., when it comes to allocation and multifunctional processes) as well as when it comes to model electricity supply. RED for example shall be clearer on how to define the electricity region while EPD guidelines on how to define the electricity market. Although it is not realistic to aim for a single unified LCA framework, the biofuel PCR and PEFCR can be developed with RED in mind. Some aspects of the PEF methodology can perhaps also be integrated into RED III that is currently under development. This would enhance the broader adoption of the frameworks among fuel producers. Finally, the involvement and engagement of the industry, and fuel producers themselves is very important. Industry initiatives are essential for the development of biofuel PCR and PEFCR while the general development of the three frameworks can also be influenced. In this study, we also investigated the relationship between the LCA frameworks and schemes for chain of custody certification (CoCC), in particular schemes for mass balance certifications (MBC) to investigate to what extent these schemes complement or overlap with LCA. The purpose of MBC schemes and LCA are different, in the sense that the first aim at verifying the sources and sustainability of total amounts of raw materials used by tracking them throughout the value chain, while the second at quantifying specific environmental impact. The system boundaries are similar, since both cover the entire value chain, but may be applied differently depending on the detailed frameworks applied and choices made in applying the MBC schemes. By identifying and clearly illustrating the variations among the studied frameworks the study enhances application, development, and harmonization of LCA, in a broader perspective, informs LCA practitioners but also decision makers and provides insights on how the identified challenges can be addressed.
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