17,039 research outputs found
Northern Lights: Four Energy Futures of the North
No full textFunder: Arctic Center of Energy (ACE);Full text license: CC BY-NC-SAEnergy Futures of Northern Swede
National Energy System Modelling for Supporting Energy and Climate Policy Decision-making: The Case of Sweden
No full textEnergy system models can contribute in evaluating impacts of energy and climate policies. The process of working with energy system models assists the understanding of the quantita-tive relationships between different parts of the energy system and between different time periods, under various assumptions. With the aim of improving the ability of national energy system models to provide robust and transparent input to the decision-making process, a three-step energy modelling process is introduced based on the literature on system analysis and energy modelling. This process is then used to address five different research questions, which are based on (but not identical to) six embedded papers. In the first step (step 1) the ‘real’ system is simplified and conceptualised into a model, where the main components and parameters of a problem are represented. In order to attain robust results, it is important to focus not only on what needs to be included in the model, but also on what can be left out. In order not to add noise to the analysis, there is a trade-off between what is desired and what can be included in terms of data. In the second step (step 2), all assumptions are sorted within a mathematical model and the algorithms solved. The structure of the model is found crucial for the possibility to trace the results back to the assumptions (transparency). In the last step (step 3), the model results are interpreted together with aspects not captured in the model (e.g. non-economic preferences, institutional barriers), and discussed in relation to the direct assumptions provided to the model (step 1) and to the implicit assumptions due to the choice of model (step 2). All three steps are essential in order to achieve robust and transparent policy analyses, and all three steps contribute to the learning about the ‘real’ system.
The embedded papers (Paper I-VI) deal with issues of particular relevance for long-term analysis of the Swedish energy system. The results of Paper I illustrate the importance of capturing the seasonal and daily variations when representing cross-border trade of electricity in national models; a too simplified representation will make the model overestimate the need for installed power capacity in Sweden. Paper II presents a methodology for estimating the ‘useful demand’ for heating and cooling based on national statistics, which is useful as most energy system models are driven by ‘useful demand’, while national statistics are based on the measurable ‘final energy consumption’. Paper III compares the technical potential of com¬bined heat and power (CHP) from different approaches and calculates the economic potential of CHP using a European energy system model (EU-TIMES). The comparison the technical potential of the different approaches reveals differences in definitions of the potential as well as in the system boundary. The resulting economic potential of CHP in year 2030 is shown to be significantly higher compared to today’s level, even though conservative assumptions regarding district heating were used. Paper IV assesses the impacts of district heating on the future Swedish energy system, first by a quantitative analysis using TIMES-Sweden and then by discussing aspects that cannot be captured by the model. Paper V compares different climate target scenarios and examines the impacts on the resulting total system cost with and without the addition of ancillary benefits of reductions in domestic air-pollution. The results reflect the fact that carbon dioxide emission reductions abroad imply a lost opportunity of achieving substantial domestic welfare gains from the reductions of regional and local environmental pollutants. Paper VI presents and discusses an iteration procedure for soft-linking a national energy system model (TIMES-Sweden) with a national CGE model (EMEC). Some aspects of the way in which we perform the soft-linking are not standard in the literature (e.g., the use of direction-specific connection points). By applying the iteration process, the resulting carbon emissions were found to be lower than when the models are used separately
Rapid and simultaneous detection of multiple mutations by pooled and multiplex single nucleotide primer extension: Application to the study of insulin-responsive glucose transporter and insulin receptor mutations in non-insulindependent diabetes
No full textThe application of molecular scanning techniques to the detection of potentially pathogenic mutations in candidate genes in patients with non-insulin-dependent diabetes has revealed a number of molecular variants of uncertain pathophysiologic significance. The determination of the significance of such variants requires large-scale population studies of the prevalence of the mutant in affected and control groups. Herein, we describe two adaptations of the technique of single nucleotide primer extension (SNuPE) which allow the simultaneous examination of large numbers of alleles at multiple loci. The usefulness of these adaptations is illustrated by their application to the simultaneous detection of three point mutations, two in the tyrosine kinase domain of the insulin receptor and one in the insulin-responsive glucose transporter(GLUT4)in a highly insulin-resistant NIDDM population. By pooling genomic or amplified DNA and performing the SNuPE reactions with three primers of different length we could readily examine 300 alleles on a single 20 lane gel. Using pooled SNuPE, we also examined a large British Caucasian control population for the prevalence of GLUT4II e 383, a variant which has previously been reported only in NIDDM. GLUT4 II e 383 was detected in 2/42 of the highly insulin-resistant NIDDM subjects and 4/240 middleaged blood donors. Family studies and examination of the expressed mutant transporter will be necessary to establish whether this mutation is of functional significance. Pooled and multiplex SNuPE are powerful techniques with wide applicability to population genetic studies of specific mutaitions.</p
Energy System Models for City Climate Mitigation Plans—Challenges and Recommendations
No full textMany cities around the world have adopted climate neutrality targets, and, to reduce their greenhouse gas emissions, they need climate action plans. Energy system optimization models (ESOMs) can be used as tools to support their energy transitions. ESOMs have been in use at the national level for several years and also have recently been used at the city level. Even though several researchers have focused on how city ESOMs can be developed, the literature lacks a discussion of the challenges that are faced in data collection during model development. In this paper, we share the challenges encountered in the model development, as well as in the scenario development and recommend practical solutions for overcoming these challenges. The following three challenges were identified and discussed in the model development process: (a) data availability and quality; (b) communication; and (c) knowledge and background of civil servants and researchers. The main challenges in the scenario development were: (a) parameter selection and (b) complexity. It was found that explanation of the terminology used in ESOMs, presentation of the model structure and preliminary base-year results were crucial actions for overcoming challenges during model development. During the scenario development, collaboration between modelers and civil servants when reviewing parameter combinations and working with preliminary scenario results were decisive strategies for improving the civil servants’ understanding of ESOMs. Complementarily, it was found that continuous communication between the researcher and the civil servant and good comprehension of the model on the municipality's side helped improve the usefulness of ESOMs in cities’ energy transitions.</p
Net-Zero CO2-Emission Pathways for Sweden by Cost-Efficient Use of Forestry Residues
No full textSweden has committed to reducing its domestic greenhouse gases by 85% by 2045, compared with 1990 levels. Due to the challenge of reducing other greenhouse gases, this commitment is regarded as a net zero CO2 emission target. Biomass is today an important part of the Swedish energy supply and has the potential to increase even further, mainly through utilization of forest residues. To explore different net zero emission pathways with an emphasis on where domestic biomass resources could be used most cost-efficiently, we employed the energy system optimisation model TIMES-Sweden. The results of our study show that biomass is used throughout the energy system. Stringent climate targets and district heating encourage the use of waste heat from biofuel production that results in a more resource efficient use of biomass. Finally, the findings also show that a significant reduction of CO2 emission is difficult to achieve for freight transportation and energy-intensive industry without an increased use of forestry residues.</p
Accounting for carbon flows into and from (bio)plastic in a national climate inventory
No full textDespite the time-dependent behavior of carbon stored in plastic materials, literature assessing carbon flows into and from plastic typically applies a static approach. To better understand the climate impacts of such storage, this study explores how carbon stored in plastics can contribute over time to the national climate inventory with various emphasis on recycling. This is accomplished by implementing material stock change estimations for carbon in plastic materials that follow first-order decay and include impacts from recycling rates in the Integrated MARKAL-EFOM System model generator for Sweden (TIMES-Sweden). Thereafter, three approaches to how carbon released from the plastic material stock is accounted for in the national climate inventory were applied to determine how each approach affects resulting emission and net-zero pathways in different recycling rate scenarios. An accounting approach that follows the first-order decay pattern of material stocks was found to be important for capturing the impacts of recycling and for neither over- nor underestimating the emission impact from carbon stored in plastics. Accounting for carbon stored in plastics may provide important incentives for producing renewable plastics and reducing dependence on carbon removal technologies. Because of its synergies with recycling, the carbon storage potential of plastic products is well worth recognizing and promoting in a policy setting that aims for circularity. For Sweden, this reduces the need for bioenergy carbon capture and storage and makes more biomass-based carbon and electricity available for use elsewhere in the energy system.Validerad;2023;Nivå 2;2023-02-10 (joosat);This article has previously appeared as a manuscript in a thesis.Licens fulltext: CC BY License</p
Recoupling Climate Change and Air Quality: Exploring Low-Emission Options in Urban Transportation Using the TIMES-City Model
No full textFossil fuels in transportation are a significant source of local emissions in and around cities; thus, decarbonising transportation can reduce both greenhouse gases (GHGs) and air pollutants (APs). However, the degree of these reductions depends on what replaces fossil fuels. Today, GHG and AP mitigation strategies are typically ‘decoupled’ as they have different motivations and responsibilities. This study investigates the ancillary benefits on (a) APs if the transport sector is decarbonised, and (b) GHGs if APs are drastically cut and (c) the possible co-benefits from targeting APs and GHGs in parallel, using an energy-system optimisation model with a detailed and consistent representation of technology and fuel choices. While biofuels are the most cost-efficient option for meeting ambitious climate-change-mitigation targets, they have a very limited effect on reducing APs. Single-handed deep cuts in APs require a shift to zero-emission battery electric and hydrogen fuel cell vehicles (BEVs, HFCVs), which can result in significant upstream GHG emissions from electricity and hydrogen production. BEVs powered by ‘green’ electricity are identified as the most cost-efficient option for substantially cutting both GHGs and APs. A firm understanding of these empirical relationships is needed to support comprehensive mitigation strategies that tackle the range of sustainability challenges facing cities
National Energy System Modelling for Supporting Energy and Climate Policy Decision-making: The Case of Sweden
No full textEnergy system models can contribute in evaluating impacts of energy and climate policies. The process of working with energy system models assists the understanding of the quantita-tive relationships between different parts of the energy system and between different time periods, under various assumptions. With the aim of improving the ability of national energy system models to provide robust and transparent input to the decision-making process, a three-step energy modelling process is introduced based on the literature on system analysis and energy modelling. This process is then used to address five different research questions, which are based on (but not identical to) six embedded papers. In the first step (step 1) the ‘real’ system is simplified and conceptualised into a model, where the main components and parameters of a problem are represented. In order to attain robust results, it is important to focus not only on what needs to be included in the model, but also on what can be left out. In order not to add noise to the analysis, there is a trade-off between what is desired and what can be included in terms of data. In the second step (step 2), all assumptions are sorted within a mathematical model and the algorithms solved. The structure of the model is found crucial for the possibility to trace the results back to the assumptions (transparency). In the last step (step 3), the model results are interpreted together with aspects not captured in the model (e.g. non-economic preferences, institutional barriers), and discussed in relation to the direct assumptions provided to the model (step 1) and to the implicit assumptions due to the choice of model (step 2). All three steps are essential in order to achieve robust and transparent policy analyses, and all three steps contribute to the learning about the ‘real’ system.The embedded papers (Paper I-VI) deal with issues of particular relevance for long-term analysis of the Swedish energy system. The results of Paper I illustrate the importance of capturing the seasonal and daily variations when representing cross-border trade of electricity in national models; a too simplified representation will make the model overestimate the need for installed power capacity in Sweden. Paper II presents a methodology for estimating the ‘useful demand’ for heating and cooling based on national statistics, which is useful as most energy system models are driven by ‘useful demand’, while national statistics are based on the measurable ‘final energy consumption’. Paper III compares the technical potential of com¬bined heat and power (CHP) from different approaches and calculates the economic potential of CHP using a European energy system model (EU-TIMES). The comparison the technical potential of the different approaches reveals differences in definitions of the potential as well as in the system boundary. The resulting economic potential of CHP in year 2030 is shown to be significantly higher compared to today’s level, even though conservative assumptions regarding district heating were used. Paper IV assesses the impacts of district heating on the future Swedish energy system, first by a quantitative analysis using TIMES-Sweden and then by discussing aspects that cannot be captured by the model. Paper V compares different climate target scenarios and examines the impacts on the resulting total system cost with and without the addition of ancillary benefits of reductions in domestic air-pollution. The results reflect the fact that carbon dioxide emission reductions abroad imply a lost opportunity of achieving substantial domestic welfare gains from the reductions of regional and local environmental pollutants. Paper VI presents and discusses an iteration procedure for soft-linking a national energy system model (TIMES-Sweden) with a national CGE model (EMEC). Some aspects of the way in which we perform the soft-linking are not standard in the literature (e.g., the use of direction-specific connection points). By applying the iteration process, the resulting carbon emissions were found to be lower than when the models are used separately
Assessing Sustainability of Regional Climate and Energy Targets at Local Level for Supporting Municipalities in Navigating the Green Transition
No full textThe European Union has implemented targets to address climate change, air pollution and increase the share of renewable energy. Local governments play a significant role in executing actions to contribute to these targets while meeting local sustainability targets. This research aims to guide the local governance by assessing the impact of implementing key energy targets from the European Union at the local level from a sustainability perspective using indicators based on sustainable development goals. An energy system optimization model is used to assess the case study of Gällivare, a municipality in Northern Sweden. The results show that localized climate and air quality targets effectively support the integration of renewable energy, improvements in energy efficiency, and reductions in final energy consumption. Air quality targets correspond carbon reduction targets and subsequently leading to the net zero emission. However, while air pollution targets help achieve 100% carbon dioxide reduction by 2050, achieving 100% reduction in air pollution requires specific air pollution targets.Godkänd;2025;Nivå 0;2025-06-19 (u2);Full text license: CC BY</p
Energisystem och klimatförändringar: Vad kan vi påverka och vad ska vi styra? Hur systemanalys kan stödja politiska beslut kring energiomställningen [Elektronisk resurs]
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