| 1. |
- Finnveden, Göran, et al.
(författare)
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Policy Instruments towards a sustainable waste management
- 2016
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Ingår i: Solid waste management: Policy and planning for a sustainable society. - : Apple Academic Press. - 9781771883740 - 9780429091650 ; , s. 185-246, s. 185-246
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 2. |
- Brandao, Miguel, et al.
(författare)
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RED, PEF, and EPD: Conflicting rules for determining the carbon footprint of biofuels give unclear signals to fuel producers and customers
- 2022
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Ingår i: Frontiers in Climate. - : Frontiers Media SA. - 2624-9553. ; 4
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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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| 3. |
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| 4. |
- Ekvall, Tomas, 1963, et al.
(författare)
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Incentives for recycling and incineration in LCA: Polymers in Product Environmental Footprints
- 2021
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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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| 5. |
- Ekvall, Tomas, 1963, et al.
(författare)
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Modelling incineration for more accurate comparisons to recycling in PEF and LCA
- 2021
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Ingår i: Waste Management. - : Elsevier BV. - 0956-053X .- 1879-2456. ; 136, s. 153-161
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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. |
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| 7. |
- Finnveden, Göran, et al.
(författare)
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Policy instruments towards a sustainable waste management
- 2013
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Ingår i: Sustainability. - Basel : MDPI AG. - 2071-1050. ; 5:3, s. 841-881
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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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| 8. |
- Poulikidou, Sofia, 1984, et al.
(författare)
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Impacts on fuel producers and customers of conflicting rules for life cycle assessment
- 2022
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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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| 9. |
- Tillman, Anne-Marie, 1958, et al.
(författare)
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Choice of system boundaries in life cycle assessment
- 1994
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Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526. ; 2:1, s. 21-29
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Tidskriftsartikel (refereegranskat)abstract
- System boundaries in life cycle assessments (LCA) must be specified in several dimensions: boundaries between the technological system and nature, delimitations of the geographical area and time horizon considered, boundaries between production and production of capital goods and boundaries between the life cycle of the product studied and related life cycles of other products. Principles for choice of system boundaries are discussed, especially concerning the last dimension. Three methods for defining the contents of the analysed system in this respect are described: process tree, technological whole system and socio-economic whole system. The methods are described in the application's multi-output processes and cascade recycling, and examples are discussed. It is concluded that system boundaries must be relevant in relation to the purpose of an LCA, that processes outside the process tree in many cases have more influence on the result than details within the process tree, and that the different methods need to be further compared in practice and evaluated with respect to both relevance, feasibility and uncertainty.
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| 10. |
- Ahlgren, Erik, 1962, et al.
(författare)
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Assessing long-term sustainability of district heating systems
- 2012
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Ingår i: Proceedings EcoBalance Yokohama Nov 20-23 2012.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Biomass has become the main fuel for district heating (DH) systems in Sweden, and the substitution of biomass for oil during the last decades has led to considerably reduced CO2 emissions within the DH systems. Today, biomass is used both in heat- only boilers and, increasingly, in combined heat-and-power plants. District heating contributes also to increased sustainability through the utilization of industrial waste heat, which substitutes for primary energy use.With increasing pressure on constrained biomass resources and due to the geographical distribution of waste-heat sources, the municipal DH systems need to look for new solutions in order to further reduce their dependency on primary energy sources and enhance their sustainability. An integration of local systems into a regional heat system would allow for utilization of an increasing amount of waste heat, to capture scale effects of biomass combined heat and power plants and also to compensate for load profile differences between the local systems. DH systems are in addition being increasingly integrated with the power system and also with biorefineries through the production of bio transport fuels. Thus, the role of DH systems is becoming increasingly complex. This calls for new tools and methods to assess the sustainability of various possible future options and developments.The aim of the study is to assess the long-term sustainability of different DH developments with a focus on possibilities for integration of local DH systems into a regional system. In order to assess the sustainability in a long-term perspective of future DH options, we combine methods such as energy systems modeling and life cycle assessment in a procedural framework called life cycle sustainability assessment. The energy systems model applied is an optimizing bottom-up model. The study concerns the Vastra Gotaland region of Sweden and our model represents all the municipal DH systems at a detailed level. This presentation will mainly focus on the methodological aspects of the work: on how the different methods can be integrated and applied in a sustainability assessment of future district heating.
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| 11. |
- Ahlgren, Serina, et al.
(författare)
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Review of methodological choices in LCA of biorefinery systems - key issues and recommendations
- 2015
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Ingår i: Biofuels, Bioproducts and Biorefining. - : Wiley. - 1932-1031 .- 1932-104X. ; 9:5, s. 606-619
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Forskningsöversikt (refereegranskat)abstract
- The current trend in biomass conversion technologies is toward more efficient utilization of biomass feedstock in multiproduct biorefineries. Many life-cycle assessment (LCA) studies of biorefinery systems have been performed but differ in how they use the LCA methodology. Based on a review of existing LCA standards and guidelines, this paper provides recommendations on how to handle key methodological issues when performing LCA studies of biorefinery systems. Six key issues were identified: (i) goal definition, (ii) functional unit, (iii) allocation of biorefinery outputs, (iv) allocation of biomass feedstock, (v) land use, and (vi) biogenic carbon and timing of emissions. Many of the standards and guidelines reviewed here provide only general methodological recommendations. Some make more specific methodological recommendations, but these often differ between standards. In this paper we present some clarifications (e.g. examples of research questions and suitable functional units) and methodological recommendations (e.g. on allocation).
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| 12. |
- Andrae, Anders, 1973, et al.
(författare)
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The shift to lead-free solders - assessed through attributional and consequential life cycle inventory
- 2004
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Ingår i: InLCA/LCM Internet conference.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Electronics packaging is a research field that deals with everything in electronics, from the chip to the complete system, including the solder interconnection materials. As of July 1st of 2006, lead will not be allowed in solder pastes. This has called for evaluations of alternatives to tin-lead solders, and especially the environmental consequences of the shift from tin-lead solder paste (TL) to lead-free solder paste (LF). In 2003 a life cycle assessment (LCA) was initiated, having two aims: (i) to compare an TL (62% tin, 36% lead, 2% silver) to an LF (95.5% tin, 3.8% silver, 0.7% copper); both pastes assumed to include 10% flux, and (ii) to compare attributional and consequential LCA methodologies. The attributional LCA describes the environmental burdens of the solder life cycle. It describes, for example, the obvious fact that the shift from TL to LF means that lead is essentially eliminated from the solder life cycle. Our attributional LCA is largely based on literature data. Lacking environmental data for flux production, we used the economic input-output model from Carnegie Mellon to obtain approximate values . Preliminary results from the attributional LCA, indicate that LF contributes 10% more to the global warming potential (GWP) than TL. 60% of the difference, can be related to an increased reflow energy consumption, and 40% to an increased tin production. The production of flux contributed to about 5 % of the total GWP results for both solders. We have recently started the consequential LCA. It aims at describing how the environmental burdens of the technosphere are affected by a shift from TL to LF. It will describe, for example, to what extent the shift means that the total use of lead is reduced, and to what extent it means that the use of lead will increase in other life cycles. We do not expect the consequential LCA to include all inputs to the solder, because, for each input in the analysis, we need to investigate the supply curve as well as the demand curve, identifying price elasticities, marginal production, and marginal consumption.
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| 13. |
- Andreasi Bassi, Susanna, et al.
(författare)
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A life cycle assessment framework for large-scale changes in material circularity
- 2021
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Ingår i: Waste Management. - : Elsevier BV. - 0956-053X .- 1879-2456. ; 135, s. 360-371
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Tidskriftsartikel (refereegranskat)abstract
- Increasing material circularity is high on the agenda of the European Union in order to decouple environmental impacts and economic growth. While life cycle assessment (LCA) is useful for quantifying the associated environmental impacts, consistent LCA modeling of the large-scale changes arising from policy targets addressing material circularity (i.e., recycled content and recycling rate) is challenging. In response to this, we propose an assessment framework addressing key steps in LCA, namely, goal definition, functional unit, baseline versus alternative scenario definition, and modeling of system responses. Regulatory and economic aspects (e.g., trends in consumption patterns, market responses, market saturation, and legislative side-policies affecting waste management) are emphasized as critical for the identification of potential system responses and for supporting regulatory interventions required to reach the intended environmental benefits. The framework is recommended for LCA studies focusing on system-wide consequences where allocation between product life cycles is not relevant; however, the framework can be adapted to include allocation. The application of the framework was illustrated by an example of implementing a policy target for 2025 of 70% recycled content in PET trays in EU27+1. It was demonstrated that neglecting large-scale market responses and saturation lead to an overestimation of the environmental benefits from the policy target and that supplementary initiatives are required to achieve the full benefits at system level.
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| 14. |
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| 15. |
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Ekvall, Tomas, 1963
(författare)
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Attributional and consequential life cycle assessment
- 2020
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Ingår i: Sustainability Assessment at the 21st century. - : IntechOpen. ; , s. 42-62
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- An attributional life cycle assessment (ALCA) estimates what share of the global environmental burdens belongs to a product. A consequential LCA (CLCA) gives an estimate of how the global environmental burdens are affected by the production and use of the product. The distinction arose to resolve debates on what input data to use in an LCA and how to deal with allocation problems. An ALCA is based on average data, and allocation is performed by partitioning environmental burdens of a process between the life cycles served by this process. A CLCA ideally uses marginal data in many parts of the life cycle and avoids allocation through system expansion. This chapter aims to discuss and clarify the key concepts. It also discusses pros and cons of different methodological options, based on criteria derived from the starting point that environmental systems analysis should contribute to reducing the negative environmental impacts of humankind or at least reduce the impacts per functional unit: the method should be feasible and generate results that are accurate, comprehensible, inspiring, and robust. The CLCA is more accurate, but ALCA has other advantages. The decision to make an ALCA or a CLCA should ideally be taken by the LCA practitioner after discussions with the client and possibly with other stakeholders and colleagues.
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| 20. |
- Ekvall, Tomas, 1963, et al.
(författare)
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Avfall som bränsle
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- SammanfattningBakgrundAvfallet blir ett allt viktigare bränsle för fjärrvärmeproduktionen. Det är en följd av förbudet mot att deponera brännbart avfall. En framtida, stor import av avfall förstärker den effekten. Avfallsförbränningen påverkar också elsystemet. Fjärrvärme från avfall konkurrerar å ena sidan ut elbaserad fjärrvärme. Å andra sidan konkurrerar konventionell avfallsförbränning också ut annan, mer effektiv kraftvärmeproduktion. Forskningens inriktningSedan 1987 har Energisystemteknik arbetat med systemstudier av lokala, regionala och nationella avfallshanteringssystem. Vår huvudinriktning är att analysera och utveckla metoder och modeller för att analysera det övergripande avfallshanteringssystemet med fokus på energirelaterade frågor. Under treårsperioden 2001-2003 inriktades forskningsverksamheten vid avfallsgruppen framförallt på fyra delprojekt:Avfallsförbränning i de framtida fjärrvärmesystemen. Avfallsförbränningen i Sverige kommer att nästan fördubblas under de närmaste åren. Det har givit upphov till många känslor och åsikter, inte bara inom avfallsområdet, utan även hos fjärrvärmeaktörerna. I detta delprojekt studerade vi vilka bränslen avfallet konkurrerar med i fjärrvärmesektorn, och hur kraftvärmeproduktionen påverkas av utbyggnaden.Import av avfallsbränslen. Under de senaste tio åren har avfallsbranschen fört åtskilliga diskussioner kring frågor om import av avfallsbaserade bränslen. Kärnfrågan har varit om man ska förhindra, acceptera eller till och med förorda avfallshandel mellan länderna inom Norden och EU. I detta delprojekt studerar vi drivkrafterna för avfallsimport, och hur dessa drivkrafter kan utvecklas i framtiden.Slam som bränsle och näringsämne. På grund av tungmetallhalter och larmrapporter rörande t ex risken för spridning av sjukdomar och bromerade flamskyddsmedel, har det blivit svårt att få avsättning för slam på åkermark. År 2005 införs dessutom ett förbud mot deponering av organiskt avfall vilket även kommer att gälla för slam. Mot denna bakgrund växer nya tekniker och metoder fram för att behandla slammet och utvinna energi och/eller näringsämnen ur det. Vi har studerat de effekter framväxande teknikerna ger upphov till i avfallshanteringssystemet, energisystemet och vatten- och avloppsreningssystemet.Ny avfallsteknik. En trolig följd av att allt mer avfall styrs mot förbränning är att mottagningsavgifterna till avfallsförbränning stiger kraftigt. Då ökar incitamenten för andra aktörer att utveckla ny teknik som har andra egenskaper än avfallsförbränning, t ex en större elproduktion eller en mer stabil restprodukt. I detta delprojekt fokuserar vi på pyrolys och annan förgasning av avfallet. Vi jämför dessa mot konventionell avfallsförbränning. ResultatSom en följd av deponiförbudet för brännbart avfall planerar fjärrvärmeföretagen i Sverige att nästan fördubbla avfallsförbränningen. Det kommer att påverka fjärrvärmeproduktionen olika i olika kommuner. Sett över hela landet kommer mängden fjärrvärme från avfall att öka med 6,6 TWh/år. Den totala mängden fjärrvärme blir dock bara 0,9 TWh/år större. Det betyder att 5,7 TWh/år av annan fjärrvärmeproduktion konkurreras ut. Det är framförallt fjärrvärmeproduktion baserad på biobränsle (3,3 TWh/år), men även fjärrvärme som produceras med olja (0,6 TWh/år), naturgas (0,5 TWh/år), spillvärme (0,4 TWh/år), värmepumpar (0,3 TWh/år) mm. I teorin kan avfall användas för att minska användningen av fossila bränslen. Våra resultat visar att avfallet i praktiken snarare konkurrerar ut biobränslen från fjärrvärmeproduktionen. Om syftet är att minimera den totala användningen av fossila bränslen, behöver det biobränsle som konkurreras ut från fjärrvärmesektorn hitta andra marknader.Mottagningsavgifterna till avfallsförbränning är betydligt lägre i Sverige än i Tyskland, Norge, Holland och Danmark. En viktig förutsättning för att kunna hålla ned kostnaderna vid avfallsförbränning är att det finns avsättning för den utvunna energin. I detta avseende har Sverige en gynnsam position i jämförelse med Norge, Holland och Tyskland. I Sverige liksom i Danmark är fjärrvärmen väl utbyggd, vilket innebär stora marknader för den utvunna energin. Svensk avfallsförbränning gynnas också av energi- och koldioxidskatterna som utgår på förbränning av fossila bränslen. Dessa skatter har drivit upp produktionskostnaderna för fjärrvärmeproduktion vilket innebär att värdet på värmen som framställs från avfallet har ökat. Deponiförbud och höga deponiskatter i Danmark, Norge och Holland samt skatt på avfallsförbränning i Danmark och Norge ger också ekonomiska incitament till att transportera avfallet till förbränning i Sverige. Återföring av slam till åkermark har lägre kostnader men större miljöpåverkan än de övriga alternativ för slamhantering som vi studerat: samförbränning av slam och avfall, BioCon-processen och Cambi-KREPRO-processen. Samförbränning har högst kostnader men minst miljöpåverkan. De två andra teknikerna, som syftar till att både utvinna fosfor och energi ur slammet, är nya och oprövade i kommersiella sammanhang. Data över dessa tekniker är därmed behäftade med stora osäkerheter. Skillnaderna mellan de två nya teknikerna är dock relativt liten. Resultaten gäller specifikt för Göteborg. För att generalisera dem till hela Sverige krävs en analys av effekterna i de lokala fjärrvärmesystem som berörs.Det är svårt att producera elenergi effektivt med avfall som bränsle. Därför kommer den planerade utbyggnaden av avfallsförbränning att leda till att potentialen för elproduktion i kraftvärmeverk minskar med ca 0,4 TWh/år. En större mängd elenergi skulle kunna produceras från avfallet om det förgasas eller pyrolyseras och man eldar den bildade gasen. Pyrolys eller förgasning har också fördelen att askan kan bli mindre farlig än vid vanlig avfallsförbränning. Det verkar dock vara svårt att göra dessa tekniker kommersiellt konkurrenskraftiga.
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| 25. |
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| 26. |
- Ekvall, Tomas, 1963
(författare)
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Economists wanted in life cycle assessment
- 2002
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Ingår i: 10th International Conference of the Greening of Industry Network, Gothenburg, Sweden, June 2002.
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Konferensbidrag (refereegranskat)
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| 27. |
- Ekvall, Tomas, 1963
(författare)
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Energisystemforskarnas roller i beslutsprocessen
- 2004
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Ingår i: Sveriges Energiting 2004 - Referat från den 9:e mars, Swedish Energy Agency, Eskilstuna, Sweden. ; , s. p. 106-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 35. |
- Ekvall, Tomas, 1963, et al.
(författare)
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Modelling material recycling in life cycle assessment: how sensitive are results to the available methods?
- 2020
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Ingår i: Handbook of the Circular Economy. - : Edward Elgar Publishing. - 9781788972727 ; , s. 116-136
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In open-loop recycling, material is recycled from one product into another. Life cycle assessment quantifies the environmental impacts of a single product. This requires understanding to what extent the primary production, the recycling, and the waste management activities belong to or affect the two product systems involved: the product that provides the material for recycling or the product produced from recycled material. The challenge is to identify how much each of the products contribute to the environmental benefit of recycling, i.e., to the avoided primary production and waste management. We describe and review many of the available methods for modelling material recycling and conclude that results can be very sensitive to the method adopted. More research is required to decide what method is the most accurate. There is also a trade-off between feasibility and accurate representation of the consequences of recycling. This implies that different methods can be applicable depending on the importance of the material recycling.
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| 36. |
- Ekvall, Tomas, 1963, et al.
(författare)
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Normative ethics and methodology for life cycle assessment
- 2005
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Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526. ; 13:13-14, s. 1225-1234
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Tidskriftsartikel (refereegranskat)abstract
- Prospective life cycle assessment (LCA) provides information on the environmental consequences of individual actions. Retrospective LCA provides information about the environmental properties of the life cycle investigated and of its subsystems. In this paper we analyse the links between the choice of methodology and different theories of normative moral philosophy. The choice of electricity data in an LCA of a conference site with local hydropower production is discussed as an illustration. The two types of LCA can be related to different theories on the characteristics of a good action. Each type of LCA, as well as each of the moral theories, can be criticised from the alternative point of departure. Decisions based on retrospective LCA can have environmentally undesirable consequences. On the other hand, prospective LCA can appear unfair and result in environmentally sub-optimised systems. Both types of LCA also have methodological limitations. We cannot conclude that one type is superior to the other, but the choice of methodology should be consistent with the information sought in the LCA.
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| 37. |
- Ekvall, Tomas, 1963, et al.
(författare)
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Open-Loop Recycling: Criteria for Allocation Procedures
- 1997
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Ingår i: The International Journal of Life Cycle Assessment. ; 2:3, s. 155-162
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Tidskriftsartikel (refereegranskat)abstract
- If the aim of an LCA is to support decisions or to generate and evaluate ideas for future decisions, the allocation procedure should generally be effect-oriented rather than cause-oriented. It is important that the procedure be acceptable to decision makers expected to use the LCA results. It is also an advantage if the procedure is easy to apply. Applicability appears to be in conflict with accurate reflection of effect-oriented causalities. To make LCA a more efficient tool for decision support, a range of feasible allocation procedures that reflect the consequences of inflows and outflows of cascade materials is required.
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| 38. |
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| 39. |
- Ekvall, Tomas, 1963
(författare)
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SETAC summaries
- 2005
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Ingår i: Journal of Cleaner Production. ; 13:13-14, s. 1351-1358
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 40. |
- Ekvall, Tomas, 1963, et al.
(författare)
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Swedish waste incineration and electricity production
- 2001
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Ingår i: Waste Management System Studies; Proceedings from workshop on system studies of integrated solid waste management in Stockholm 2-3 april 2001/ Jan-Olov Sundqvist, Göran Finnveden, Johan Sundberg.
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Konferensbidrag (refereegranskat)
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| 41. |
- Ekvall, Tomas, 1963, et al.
(författare)
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System Boundaries and Input Data in Consequential Life Cycle Inventory Analysis
- 2004
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Ingår i: International Journal LCA. ; 9:3, s. 161-171
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Tidskriftsartikel (refereegranskat)abstract
- AbstractGoal, Scope and Background. A consequential life cycle assessment (LCA) is designed to generate information on the consequences of decisions. This paper includes a comprehensive presentation of the consequential approach to system boundaries, allocation and data selection. It is based on a text produced within the SETAC-Europe working group on scenarios in LCA. For most of the methodological problems, we describe ideal methodological solutions as well as simplifications intended to make the method feasible in practice.Method. We compile, summarize and refine descriptions of consequential methodology elements that have been presented in separate papers, in addition to methodological elements that have not previously been published as well as general conclusions.Results and conclusions. A consequential LCA ideally includes activities within and outside the life cycle that are affected by a change within the life cycle of the product under investigation. In many cases this implies the use of marginal data and that allocation is typically avoided through system expansion. The consequential LCI model also includes the alternative use of constrained production factors as well as the marginal supply and demand on affected markets. As a result, the consequential LCI model does not resemble the traditional LCI model, where the main material flows are described from raw material extraction to waste management. Instead, it is a model of causal relationships originating in the decision at hand or the decision-maker that the LCI is intended to inform.
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| 42. |
- Ekvall, Tomas, 1963
(författare)
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System Expansion and Allocation in Life Cycle Assessment With Implications for Wastepaper Management
- 1999
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The choice of system boundaries and allocation methods can have decisive effects on the results and conclusions of a life cycle assessment (LCA). System expansion makes it possible to model the indirect effects of a decision; however, this modelling is often based on inaccurate assumptions. Subdivision and/or allocation based on physical, causal relationships model the consequences of a decision that affects the internally used functions but not the exported functions of a multi-function process. Allocation based on gross sales value model the causes of environmental burdens. System expansion and marginal data can be used in most LCA applications. It can be expected to contribute to individual decisions and actions that result in a lower level of environmental burdens per functional unit than would have been the case without the LCA; however, the modelling of indirect and marginal effects may be restricted by other methodological requirements, such as acceptability, feasibility, and, in some applications, the need for a detailed methodological standard. This thesis includes a new approach to the allocation problem in open-loop recycling. This approach models the indirect effects of a change in the supply of, or demand for, the recycled material. It can be used for system expansion as well as for allocation. It takes important mechanisms into account, but the precision in the model can be poor. The 50/50 allocation method presented in an earlier paper can be regarded as an approximation of the new approach. Important methodological issues in the environmental comparison between recycling and waste incineration of wastepaper, old corrugated board, etc. include the modelling of indirect effects and the choice of data for electricity production. The indirect effects depend on which energy source competes with energy from wastepaper incineration, on which material is replaced by the recycled paper, and on the alternative use of forest resources that are not required for pulpwood production. All of these, as well as the marginal electricity production, depend on the time-perspective and on other waste management, forestry, and energy policies.
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| 46. |
- Eriksson, Ola, et al.
(författare)
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Life cycle assessment of fuels for district heating : A comparison of waste incineration, biomass- and natural gas combustion
- 2007
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Ingår i: Energy Policy. - : Elsevier BV. - 0301-4215 .- 1873-6777. ; 35:2, s. 1346-1362
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this consequential life cycle assessment (LCA) is to compare district heating based on waste incineration with combustion of biomass or natural gas. The study comprises two options for energy recovery (combined heat and power (CHP) or heat only), two alternatives for external, marginal electricity generation (fossil lean or intense), and two alternatives for the alternative waste management (landfill disposal or material recovery). A secondary objective was to test a combination of dynamic energy system modelling and LCA by combining the concept of complex marginal electricity production in a static, environmental systems analysis. Furthermore, we wanted to increase the methodological knowledge about how waste can be environmentally compared to other fuels in district-heat production. The results indicate that combustion of biofuel in a CHP is environmentally favourable and robust with respect to the avoided type of electricity and waste management. Waste incineration is often (but not always) the preferable choice when incineration substitutes landfill disposal of waste. It is however, never the best choice (and often the worst) when incineration substitutes recycling. A natural gas fired CHP is an alternative of interest if marginal electricity has a high fossil content. However, if the marginal electricity is mainly based on non-fossil sources, natural gas is in general worse than biofuels.
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| 47. |
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| 48. |
- Fahlén, Elsa, 1981, et al.
(författare)
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Internalisation of external costs in studies of local district-heating based energy systems
- 2008
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Ingår i: Proceedings of 11th International Symposium on District Heating and Cooling, Reykjavik, Iceland. ; , s. 233-240
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Konferensbidrag (refereegranskat)abstract
- This study aims to investigate how external costs can be internalised in an energy systems study of local district-heating aiming to assess the socio-economic cost-effectiveness of the district heating system’s operation. It shows that current Swedish energy policy instruments lead to a socio-economic suboptimal operation on the marginal production of heat in the studied district heating system of Göteborg.
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| 49. |
- Fakhri, Akram, 1976, et al.
(författare)
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LARGE-SCALE UTILISATION OF EXCESS HEAT - ASSESSMENT THROUGH REGIONAL MODELLING
- 2014
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Ingår i: The 14th International Symposium on District Heating and Cooling.
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Konferensbidrag (refereegranskat)abstract
- The use of excess heat (EH) in district heating (DH) may contribute to increased sustainability through reduced use of primary energy. In Sweden biomass has become an important DH fuel during the last decades. Currently, there is a strong focus not only on use of biomass in heat and power generation but also for the transport sector. Competition for biomass, as a limited source, is thus likely to lead to higher demand and increasing prices of biomass. This study addresses the long-term system effects and connecting costs of three DH systems though a transmission pipeline that enables an increased use of EH from a large chemical cluster. The assessment is carried out with the optimising energy systems model MARKAL_WS, in which DH systems in the Västra Götaland region of Sweden are represented individually. Options for the production of transport biofuel as one potential competitor for biomass use are also included. The results show that the investment in the pipeline is cost-efficient when our energy system optimization takes both the DH systems and the transport sector into account, resulting in reduced total system cost.
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| 50. |
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