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• Insights from transportation research used to improve comprehensive ESOM. • Capturing underlying heterogeneities by increasing contextual model resolution. • The setup underpins importance of tailoring climate strategies to specific settings. • Behavioural shifts have different implications depending on the contextual setting. • Failing to address key cost barriers delays car fleet electrification by five years. Meeting ambitious climate targets requires deep cuts in emissions from passenger transportation. Many studies point to electrification and behavioural shifts as key measures. Spatial, demographic, economic, and transport-sector-related factors shape the opportunities and preferences for change, thus setting the direction and pace of the transition. These factors typically differ between urban, suburban and low-population-density settings, a fact that is generally overlooked in comprehensive energy system optimisation models (ESOM). This study introduces a novel contextual representation of passenger transportation within a national ESOM (TIMES-Sweden). When testing the new approach, different cost barriers to electrification are found across various settings, signalling a need for different policy responses. Further, opportunities for – and impact from – shifts in travel behaviours vary significantly across settings. These results highlight the need for climate change mitigation strategies in passenger transportation which are better tailored to specific contexts. [ABSTRACT FROM AUTHOR]

We argue in this study that higher electricity expenditures increase voter support for the radical right because these parties oppose costly climate mitigation policies. We use data from Sweden, which experiences extremely high demand for heating energy during winter months. The demand for electricity differs greatly between geographical regions due to large temperature differences, from 0 in the southern regions to −50 Celsius in the north. We create our independent variable of electric grievances based on this variation, which increases faster with the spot price of electricity in neighborhoods with a low disposable income relative to the average electricity bill in that area. Using this setup, we find that electric grievances are associated with increased support for the radical right. We argue that soaring electricity prices tend to hurt parties with a mainstream profile since voters associate them them with more ambitious decarbonization policies, while the radical right gain support, since they tend to oppose costly solutions. Our results suggests that the transition to renewable energy can grind to a halt when electricity prices rise higher because voters may abandon the parties who push for the green transition. [ABSTRACT FROM AUTHOR]

• Below 200 g CO 2 eq./kWh, chargeable bus emissions lower than HVO-biodiesel hybrids. • Above 750 g CO 2 eq./kWh, diesel hybrids preferable to plug-in/all-electric buses. • Excluding operation, chassis, frame and body dominate load in all buses. • All-electric buses best for reducing local air pollution and regional impact. This study explores life cycle environmental impacts of city buses, depending on the: (1) degree of electrification; (2) electricity supply mix, for chargeable options; and (3) choice of diesel or hydrogenated vegetable oil (HVO), a biodiesel, for options with combustion engine. It is a case study, which uses industry data to investigate the impact on climate change, a key driver for electrification, and a wider set of impacts, for average operation in Sweden, the European Union and the United States of America. The results show that non-chargeable hybrid electric vehicles provide clear climate change mitigation potential compared to conventional buses, regardless of the available fuel being diesel or HVO. When fueling with HVO, plug-in hybrid and all-electric buses provide further benefits for grid intensities below 200 g CO 2 eq./kWh. For diesel, the all-electric option is preferable up to 750 g CO 2 eq./kWh. This is the case despite batteries and other electric powertrain parts causing an increase of CO 2 emissions from vehicle production. However, material processing to make common parts, i.e. chassis, frame and body, dominates the production load for all models. Consequently, city buses differ from passenger cars, where the battery packs play a larger role. In regard to other airborne pollutants, the all-electric bus has the best potential to reduce impacts overall, but the results depend on the amount of fossil fuels and combustion processes in the electricity production. For toxic emissions and resource use, the extraction of metals and fossil fuels calls for attention. [ABSTRACT FROM AUTHOR]

Multi-family housing construction (MFHC) with wood instead of concrete as frame material results in lower greenhouse gas emissions. Hence, substituting wood for concrete in MFHC in Sweden until 2030, and onwards to 2070, could be a promising climate change mitigation option. But to what extent, and how would it impact Sweden's forests? Here we assess climate and biodiversity implications - in terms of the area of old forest - of a completely wood-based future MFHC in Sweden. The wood required is assumed to be exclusively sourced as additional fellings in Swedish forests, thus carbon leakage from wood imports as well as displacement of other wood uses can be disregarded. Different types of timber frame systems and the role of varying future dwelling sizes are considered. We find that the wood needed for a complete substitution of concrete would result in very minor increases in harvests. We further register slight net additional climate change mitigation, irrespective of the wood construction system. There is a small tradeoff between climate change mitigation and biodiversity, as the area of old forest reduces slightly. The largest climate benefit, and lowest impact on Swedish forests, is provided when using timber-light frame combined with reduced dwelling size. [ABSTRACT FROM AUTHOR]

• Impact of future climate in mitigation and economic feasibility of retrofitting. • Impact of uncertainties as location, energy system and household energy prices. • Five climate scenarios, four Swedish cities, thirteen retrofitting measures. • Decisions relying purely on cost-effectiveness will hinder energy retrofitting. • Cost definitions and policies for buildings sector need to be revised. Deep and rapid decarbonization of the building sector requires energy demand reductions and the incorporation of renewable-energy sources. Energy retrofitting of existing buildings is a central strategy in climate mitigation and has often been highlighted as a cost-effective strategy. However, decisions on these strategies are often hampered by modeling assessments that are limited by contextual, methodological, parametric, input, or output constraints. Here, we present a novel methodology to investigate the solid economic feasibility in building retrofit evaluations with mitigation measures. We first calculate the variations in the energy saving potentials and costs for 13 energy saving measures and five climate change scenarios. We then compare the obtained uncertainty due to a changing climate to other uncertainties, such as the boundaries for emission inventories and energy system development. Four cities in Sweden are modeled, which are responsible for half of the country's residential energy use. We find that the profitability of the retrofitting actions is primarily determined based on the annualized investments and energy saving potentials. Future climate has a less determinant role, with uncertainties similar to those of future consumer price development and fuel emission factors. Retrofits that only affect the energy need for space heating are more robust than changes in electricity usage. We conclude that strategies for building retrofitting should focus on prioritizing energy savings and mobilizing investments that may not be profitable based on the current techno-economic perspective. [ABSTRACT FROM AUTHOR]

A variety of climate mitigation strategies is available to mitigate climate impacts of buildings. Several studies evaluating the effectiveness of these strategies have been performed at the building stock level, but do not consider the technological change in building material manufacturing. The objective of this study is to evaluate the climate mitigation effects of increasing the use of biobased materials in the construction of new residential dwellings in Sweden under future scenarios related to technological change. A model to estimate the climate impact from Swedish new dwellings has been proposed combining official statistics and life cycle assessment data of seven different dwelling typologies. Eight future scenarios for increased use of harvested wood products are explored under different pathways for changes in the market share of typologies and in energy generation. The results show that an increased use of harvested wood products results in lower climate impacts in all scenarios evaluated, but reductions decrease if the use of low-impact concrete expands more rapidly or under optimistic energy scenarios. Results are highly sensitive to the choice of climate impact metric. The Swedish construction sector can only reach maximum climate change mitigation scenarios if the low-impact building typologies are implemented together and rapidly. [ABSTRACT FROM AUTHOR]

More cities have started trajectories to become climate neutral, especially for their territorial emissions. However, while cities are also targeting consumption-based emissions, whether their plans are sufficient to become climate neutral from both a territorial and a consumption-based perspective remains unclear. We designed a conceptual framework based on a literature review of urban climate mitigation and reviewed mitigation–related documents from nine Swedish cities. We found a strong political will and solid targets but gaps in the plans and actions mostly related to transport, construction and food. Municipal governments use "soft" policy instruments to meet climate targets; at times, economic instruments contradict the vision. Our evaluation indicates a disconnect between intent and outcomes. More regulatory instruments must be deployed to become climate-neutral, and economic incentives must be aligned with the vision. Understanding how climate mitigation strategies affect resources within the city will be necessary to ensure the acceptance and uptake of climate action plans. Collaboration with superordinate governments, within and outside national borders, will be essential to align on policy and policy instruments. What is known? • Cities play a pivotal role in reducing emissions and achieving climate neutrality, yet in our sample of nine Swedish cities, territorial and consumption-based emissions have decreased little since 2014. What are the new findings? • Our review of the cities' environmental plans against our conceptual framework shows high political commitment to achieving climate neutrality. Still, it reveals gaps in strategies and actions, especially for transport and household consumption. Economic instruments are not always in line with reducing climate emissions. • Furthermore, collaborating with superordinate governments is essential to achieving targets, but this is insufficiently addressed within the municipal governments' plans. What do the new findings imply? • Regulatory instruments will be required to support "modal shifts" in behaviour and meet consumption-based climate targets. Understanding the financial consequences of climate mitigation strategies will also be essential to assess the feasibility and societal acceptance of these strategies at a city level. [ABSTRACT FROM AUTHOR]

In order to tap the energy saving and climate mitigation potential of buildings, transaction costs of implementing energy efficient technologies need to be better understood and ultimately reduced. The objective of this paper is to identify and analyze the nature and scale of transaction costs resulting from the application of the passive house concept in energy efficient renovations. Related conceptual choices are also discussed. This study explores learning strategies as a potential to reduce transaction costs. It focuses on transaction costs borne by building owners and building developers in the planning and implementation phases of a passive house-oriented renovation in Sweden. Results reveal three main sources of transaction costs: due diligence, negotiations and monitoring. The analysis shows that transaction costs are non-negligible and for individual cost sources the scale can be three times higher than for conventional renovations. To reduce transaction costs, various learning strategies such as study visits, demonstration projects, new forms of meetings and new channels of (written) information were found. These strategies have the potential to half transaction costs of future renovation projects. [ABSTRACT FROM AUTHOR]

Reducing greenhouse gas (GHG) emissions is an urgent challenge for mankind. However, as aggregate emissions continue to rise, necessary changes in industrial practices are lagging behind. The article addresses this discrepancy by exploring how the issue of GHG reduction is channeled from policy to industry, in one of the more GHG intensive sectors, agriculture. We adopt the translation perspective to analyze and discuss how the climate issue travels between contexts. Our study explores the activities involved as advisors, functioning as translating agents within Swedish agri-policy, inform producers about the issue of GHG reduction. The study sheds new light on the effectiveness of mitigation policy in promoting practice change and illustrates how translation is an analytical framework suitable for studying this within different industries. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a life cycle perspective is used to analyse Europabanan, a proposed high-speed rail track in Sweden. The life cycle emissions reductions are found to be 550,000tons of CO2-equivalents per annum by 2025/2030 with almost 60% of this coming from a shift from truck to rail freight and 40% from a shift from air and road travel to high-speed rail travel. In contexts similar to Sweden, it is thus an important issue whether a large increase is required in freight rail capacity anyway, since high-speed rail investments may not be justified for the passenger markets alone. The study also indicates that a substantial share of emissions due to construction of the new railway could be counterbalanced through the reduced need for building and maintaining roads and airports, and for manufacturing cars. [Copyright &y& Elsevier]

• Ecosystem services have synergies and trade-offs between sustainability dimensions. • The complex nature of ecosystem model output make communicating findings difficult. • We developed modeled based CIs to evaluate forest management strategies. • Composites were systematically evaluated across three regions and climate periods. Forests provide a wide range of ecosystem services, and ecosystem models can be applied to assess the contribution of different forest management strategies to climate mitigation and adaptation. Complex model output and trade-offs between environmental, economic, and social sustainability dimensions are difficult to convey. To facilitate stakeholder communication, we developed composite indicators based on ten ecosystem service indicators obtained from ecosystem model simulations representing 19 forestry management strategies across three ecoregions and climate scenario projections in Sweden. Eight alternative composites were generated around a central framework addressing sustainability aspects in terms of wood production, preservation of biodiversity, climate change mitigation and adaptation (risk management). A combination of principal component analysis, exploratory factor analysis, Cronbach's coefficient alpha, and hierarchical cluster analysis was applied to account for the statistical relationships between indicators. Z-score normalization was superior to min-max normalization in capturing differences among management strategies. Two weighting schemes were applied, based on policy prioritizations between sub-components that reflected 1) current policy with an equal emphasis on production and biodiversity, and 2) a stronger focus on nature protection. Equal emphasis generated a larger range of scores (76.0 ± 21.2) than the focus on nature protection (32.0 ± 5.8), as the latter would provide less production benefits and thereby fewer trade-offs between production and other aspects. The final scores of the 19 management strategies fell within a variance boundary of each other, showing their contribution to different policy targets and the usefulness of combining strategies at the landscape level. The composites displayed agreement across regions and scenarios. They indicated that a shift from even-aged conifer monocultures towards a combination of continuous cover, broadleaf-mixture, and unmanaged would work well for balancing goals under changing climate conditions. [ABSTRACT FROM AUTHOR]

• Banning new internal combustion engine cars reduce tailpipe CO 2 emissions. • A ban in 2030 is not sufficient for reaching Swedish climate targets for 2030. • An earlier ban year or increased biofuel use is needed to reach targets. • Regulation of carbon footprints for new vehicles and/or batteries may be motivated. • Prospective lifecycle assessment and vehicle fleet turnover simulations are used. Banning sales of passenger cars with internal combustion engines is becoming a common climate change mitigation policy. This study analyzes the effects of such a ban on the carbon footprints of passenger car travel in Sweden using a novel vehicle turnover model and prospective lifecycle assessment, with scenarios for decarbonization of supply chains. A ban on internal combustion engines results in significantly decreased carbon footprints primarily due to reduced tailpipe CO 2 emissions. The full effect of a ban is delayed due to fleet inertia. Increasing the pace of electrification is beneficial for the carbon footprint regardless of global manufacturing decarbonization pathways. A ban in 2030 is not sufficient to reach national policy targets for the transport sector, requiring either an earlier ban (i.e., 2025) or increased biofuel use. Risks of carbon leakage may motivate extending current regulations of vehicle-specific tailpipe emissions to also cover carbon footprints for new cars. [ABSTRACT FROM AUTHOR]

Forests can help mitigate climate change in different ways, such as by storing carbon in forest ecosystems, and by producing a renewable supply of material and energy products. We analyse the climate implications of different scenarios for forestry, bioenergy and wood construction. We consider three main forestry scenarios for Kronoberg County in Sweden, over a 201-year period. The Business-as-usual scenario mirrors today's forestry while in the Production scenario the forest productivity is increased by 40% through more intensive forestry. In the Set-aside scenario 50% of forest land is set-aside for conservation. The Production scenario results in less net carbon dioxide emissions and cumulative radiative forcing compared to the other scenarios, after an initial period of 30–35 years during which the Set-aside scenario has less emissions. In the end of the analysed period, the Production scenario yields strong emission reductions, about ten times greater than the initial reduction in the Set-aside scenario. Also, the Set-aside scenario has higher emissions than Business-as-usual after about 80 years. Increasing the harvest level of slash and stumps results in climate benefits, due to replacement of more fossil fuel. Greatest emission reduction is achieved when biomass replaces coal, and when modular timber buildings are used. In the long run, active forestry with high harvest and efficient utilisation of biomass for replacement of carbon-intensive non-wood products and fuels provides significant climate mitigation, in contrast to setting aside forest land to store more carbon in the forest and reduce the harvest of biomass. • Most climate benefit from active forestry with high harvest and efficient utilisation of biomass. • Renewable biomass replaces carbon-intensive non-wood products and fuels. • Less climate benefit from setting aside forest land to store more carbon in the ecosystem. [ABSTRACT FROM AUTHOR]

Sweden and Finland have national goals to reach net negative greenhouse gas emissions before mid-century. Achieving these ambitious goals could employ negative emission technologies, such as bioenergy with carbon capture and storage, but it is unclear how this technology could be realized in an energy transition. Sweden and Finland stand out for having a large share of substantial point source emissions of biogenic carbon dioxide, in the production of pulp, heat and power. In the European Pollutant Release and Transfer Register, Sweden and Finland reported 64% and 51% biogenic emissions, respectively, in facilities emitting over 100 kt of carbon dioxide in 2017, while the corresponding collective figure for all European states in the database is 6%. This qualitative study highlights company actors' perspectives on bioenergy with carbon capture and storage within a Nordic regional context and explores their perspective on emerging tensions in the energy transition. Semi-structured interviews were conducted with 20 of the 24 companies with the largest point sources of biogenic emissions. The results are framed around four emerging tensions regarding bioenergy with carbon capture and storage from companies' perspectives in this study: (1) absence of reliable long-term policies; (2) limits to companies' climate change responsibility; (3) technical trade-offs of carbon capture; and (4) lack of customer demands for negative emissions. According to most of the companies, it is technically feasible to capture carbon dioxide, but it could be a challenge to determine who is responsible to create a financially viable business case, to enact supporting policies, and to build transport and storage infrastructure. Company representatives argue that they already contribute to a sustainable society, therefore bioenergy with carbon capture and storage is not their priority without government collaboration. However, they are willing to contribute more and could have an increasing role towards an energy transition in an international context. • BECCS discussions are on the horizon, but few companies are first movers. • Large-scale deployment of BECCS would require political and financial support. • Swedish and Finnish companies lack customer demand for negative emissions. • There are trade-offs between energy efficiency and carbon capture. • Companies consider BECCS as one of many climate change mitigation measures. [ABSTRACT FROM AUTHOR]

The demand for wood-based energy is foreseen to grow as energy and climate policies around the world promote the use of bioenergy for climate change mitigation. However, the carbon impacts of forest bioenergy range widely in the literature. The value-choices made on the response of forest management to bioenergy demand have a major influence on the results obtained from modeling exercises and may actually change the contribution of forest bioenergy from climate worsening to climate change mitigation. Despite their relevance, there is very little information, or transparency, as to the empirical basis by which these assumptions are chosen and evaluated against. This study aims to fill in this crucial knowledge gap through a mix of critical review, analysis of historical statistical data, and expert judgement. Several prominent studies reporting climate change mitigation from forest bioenergy in three countries are reviewed: Canada, Sweden, and Southeast USA. This analysis shows that the studies rely on assumptions that bioenergy demand will spur supply responses aimed at more efficient forest management and/or relative increases in forest area. Confronting literature assumptions with trends in historical data, we present the most extensive reality-check of bioenergy literature assumptions to date. We find that studies projecting a large role of forest bioenergy in climate change mitigation rely on assumptions that are too optimistic, at times outright unrealistic. We believe scientists could avoid the misinterpretation of their results and improve the policy relevance of their work by more transparent reporting of: i) value-laden assumptions, ii) their influence on the results, iii) the process and rationale behind such assumptions, especially distinguishing between assumptions that reflect incremental changes in management from assumptions requiring transformational change in several industrial sectors. • Accounted carbon benefits of forest bioenergy depend on underlying assumptions. • Forest bioenergy mitigates climate change only when additional biomass is produced. • Forest management responses assumed in the literature are overly optimistic. • Post Normal Science tools can help scientists avoid misinterpretation of results. • Scientists should better convey that model results are contingent on value-choices. [ABSTRACT FROM AUTHOR]

Transitioning from a fossil economy to a bio-economy will inevitably increase the demand for biomass production. One strategy to meet the demand is to re-cultivate set-aside arable land. This study investigated the climate impact and energy potential of grass-based biogas produced using fallow land in Uppsala municipality, Sweden. The assessment was performed on regional level for more than 1000 individual sites, using the agro-ecosystem model DeNitrification DeComposition (DNDC) in combination with time-dynamic life cycle assessment methodology. The results showed that the system could significantly increase biogas production within the region, which would reduce the climate impact by 9950 Mg CO 2 -eq per year. Compared with diesel fuel, the grass-based biogas gave a GWP reduction of 85%. However, the site-specific GWP reduction showed large spatial variability, ranging between 102 and 79% compared with diesel fuel, depending on where in the region the grass was cultivated. Two alternative scenarios were investigated, increased mineral N fertilisation and inclusion of N-fixing crops in the feedstock mixture. The highest mitigation per biogas energy produced was found for the N-fixing scenario but, because of lower yields, this scenario had lower total mitigation potential for the region than the increased fertilisation scenario. The increased fertilisation scenario had a lower climate mitigation effect per biogas energy produced, but the highest mitigation potential when the whole region was considered, because of the increased biogas production. The method applied in this study can guide land-use planning of local energy production from arable land, also for other regions. • The grass-based biogas production significantly reduced the regional climate impact. • The climate impact showed large spatial variation within the region. • The most suitable locations, from a mitigation perspective, were identified. • Increasing fertilisation intensity increased total mitigation for the region. • N fixing feedstock resulted in the highest mitigation per MJ. [ABSTRACT FROM AUTHOR]

• The life cycle climate change impact of a solar microgrid in Sweden was estimated. • Average and marginal emission factors were estimated with explicit system boundaries. • Average and marginal emission factors of electricity use in Sweden differ. • Integration of a solar microgrid into the main grid may contribute to climate change. • The environmental performance of a solar microgrid depends strongly on the context. Microgrids are small-scale electricity networks that integrate distributed electricity generation with consumers and, potentially, with storage devices. There is growing interest in these systems, as they can offer solutions for electrification of remote areas, deployment of distributed renewable energy resources, and decarbonization of electricity supply. However, the potential benefits of microgrids in terms of climate change mitigation have not yet been thoroughly assessed. In this study, Life Cycle Assessment was performed to determine the climate change impact of integrating a solar microgrid system in western Sweden into the Swedish electricity grid. To determine whether replacement of grid electricity with electricity from the microgrid can lower greenhouse gas (GHG) emissions, average and marginal GHG emission factors (EFs) for electricity use were estimated with explicit spatial and temporal resolution, using historical data on electricity generation and trade, and life cycle EFs for electricity generation technologies. The assessment, with both marginal and average EFs, showed that integration of the microgrid into the Swedish electricity grid did not provide GHG emissions abatements, as the electricity from the microgrid displaced grid electricity with lower carbon intensity. It was found that a microgrid without batteries would have lower climate change impact, but would still fail to lower overall GHG emissions. Moreover, it was demonstrated that the methodological approach used for estimation of EFs and the definition of spatial boundaries could influence the obtained results. [ABSTRACT FROM AUTHOR]

• High temperature heat pump integration into district heating network is proposed. • District heating network is studied as a heat sink and source. • Alternative refrigerant assessment is performed to replace HFC-134a and HFC-245fa. • The proposed system shows promising energy and economic performance. • The proposed integration system significantly reduces the equivalent CO 2 emission. This study illustrates the potential of high temperature heat pumps (HTHPs) integration into district heating network (DHN) through a twofold approach, using DHN as a heat sink and source. It is used as a heat sink of HTHP that uses waste heat from the supermarket's refrigeration system as a heat source whereas it is used as a heat source to HTHP that provides heat to industrial applications. When the DHN acts as the heat sink, the integrated system provides a coefficient of performance (COP) of the waste heat recovery (WHR) system between 3.2 and 5.4, reducing the operating costs between 50% and 100% with an average price ratio of 2.25 compared with the standard CO 2 refrigeration system. If the DHN is the heat source, the integrated system provides a COP from 2.8 to 5.7 for a heat sink of 110 °C. The alternative low-GWP refrigerants assessment illustrates that HC-290, HFO-1234ze(E) and HFO-1234yf were considered the ideal candidates to replace the HFC-134a, whereas HCFO-1233zd(E) and HCFO-1224yd(Z) were the most promising low-GWP refrigerants to replace HFC-245fa. Finally, the environmental results showed that the utilisation of the DHN as the heat sink in the integrated system solution produces about 60% lower equivalent CO 2 emissions than the DHN generation mix. Moreover, using DHN as the heat source, the equivalent CO 2 emissions can be reduced up to 98% in Sweden compared to conventional natural gas boilers. Hence, the combination of HTHPs and the DHN represents a step forward in the mitigation of climate change through the utilisation of sustainable energy conversion technologies. [ABSTRACT FROM AUTHOR]