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| 2. |
- Persson, Urban, 1961-
(författare)
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Realise the Potential! : Cost Effective and Energy Efficient District Heating in European Urban Areas
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Member States of EU27 need to accelerate the integration of energy efficient technology solutions to reach the 20% energy efficiency target set for 2020. At current pace, projections indicate that only half of expected primary energy reductions will be reached. To meet the energy demands of growing populations and a vibrant economy, while simultaneously reducing primary energy supplies, the European continent faces a new kind of challenge never previously encountered. The identification and application of feasible, competitive, and comprehensive solutions to this problem are of highest priority if the remaining gap is to be closed in time. How is this multi-dimensional and complex dilemma to be dissolved? In this work, expanded use of district heating technology is conceived as a possible solution to substantially reduce future primary energy demands in Europe. By extended recovery and utilisation of vast volumes of currently disregarded excess heat from energy and industry sector fuel transformation processes, district heating systems and combined generation of heat and power can improve the general efficiency of the European energy balance. To investigate the possible range of this solution, this thesis introduces a set of methodologies, theoretical concepts, and model tools, by which a plausible future excess heat utilisation potential, by means of district heat deliveries to residential and service sectors, is estimated. At current conditions and compared to current levels, this potential correspond to a threefold expansion possibility for directly feasible district heating systems in European urban areas and a fourfold increase of European excess heat utilisation.
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| 3. |
- Bhatti, Harrison John, et al.
(författare)
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Multidimensional Readiness Index for Electrification of Transportation System in China, Norway, and Sweden
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The main objective of this paper is to develop a readiness index model that can serve as an analytical tool for exploring the achievements of electrification of transportation systems. We have applied this readiness index model to evaluate the readiness positioning of China, Norway, and Sweden towards transport electrification. We have chosen these three countries as they represent diversity among countries that are in the process of adopting electrified transport system solutions. Our developed readiness index model has four key dimensions, technological readiness, political readiness, societal readiness, and economic readiness. The embeddedness of all four dimensions in one model provides a multi-perspective way of analyzing and evaluating the readiness levels of countries moving towards transforming the transportation system. Therefore, we named the model a“multidimensional readiness index.”Our main conclusions are that the political processes and political decisiveness involved are the most important factors followed by the societal needs and economic ability, with the current technology available as the fourth. Without the participation of dedicated and determined political decision-makers being involved, the other three factors are challenging to obtain. Political decision-makers need to facilitate the use of economic means to support the transformation in the society and affected industries to balance the initial economic disadvantages of the electrically-powered systems until they pass the cost disadvantage turning point. The development of the relevant technology is no longer a great barrier as it was at the beginning of this transformation, about 20 years ago. The technology for electrically powered transportation systems and devices is widely available now, although it is continuously evolving and being improved. Associated industries cannot be expected to initiate, finance, take the risk, and take the lead in this global societal transformation without clear and strong political support.Based on our multidimensional readiness index analysis, China is being positioned as the leading country in the world in the electrification of its transportation systems. This is mainly so because of the strong technology advancements, control of the entire value chain of research, development (R&D), and manufacturing of EVs, strong government decisiveness, and execution power in developing and implementing favorable electric vehicle (EV) policies. The willingness of China’s public sector to take the lead and their citizen’s support to adopt clean technology are additional factors facilitating this advancement. Norway has rapidly become one of the newcomers in electrification with large numbers of registered electric vehicles, despite lacking manufacturing industries of electric vehicles. Sweden is a rapidly developing country in the electrification of transport, with three vehicle manufacturers introducing EVs in 2021. The government has been committed to building demonstration sites for electric roads systems for more than ten years. Sweden is also working on establishing battery manufacturing facilities dedicated to the needs of electrified transportation equipment and systems.
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| 4. |
- Magnusson, Thomas, 1970-, et al.
(författare)
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Sustainability transitions in tourism : on the transformation of a fragmented sector
- 2024
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Ingår i: Tourism Geographies. - Abingdon, Oxon : Routledge. - 1461-6688 .- 1470-1340.
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Tidskriftsartikel (refereegranskat)abstract
- This conceptual paper argues that there are unrealized benefits from a cross-fertilization between research on sustainable tourism and sustainability transitions studies. With the aim to stimulate such cross-fertilization, the paper identifies three contemporary streams in sustainability transitions studies that are particularly relevant for sustainable tourism: deep transitions, transitions in practice, and the geography of transitions. These three streams present complementary perspectives, which can help reach a more nuanced understanding of transition processes in the tourism sector. The paper concludes that while research on sustainable tourism can benefit from theories, concepts, and frameworks from research on sustainability transitions, research on sustainable tourism can support further conceptual developments in sustainability transitions studies.
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| 5. |
- Egeskog, Andrea, 1981, et al.
(författare)
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Co-generation of biofuels for transportation and heat for district heating systems – an assessment of the national possibilities in the EU
- 2009
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Ingår i: Energy Policy. - Amsterdam : Elsevier BV. - 0301-4215 .- 1873-6777. ; 37:12, s. 5260-5272
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Tidskriftsartikel (refereegranskat)abstract
- Biomass gasification with subsequent synthesis to liquid or gaseous biofuels generates heat possible to use in district heating (DH) systems. The purpose here is to estimate the heat sink capacity of DH systems in the individual EU nations and assess the possibilities for biomass-gasification-based co-generation of synthetic biofuels for transportation and heat (CBH) for DH systems in the EU countries. The possibilities are assessed (i) assuming different levels of competiveness relative to other heat supply options of CBH corresponding to the EU target for renewable energy for transportation for 2020 and (ii) assuming that the potential expansion of the DH systems by 2020 is met with CBH. In general, the size of the DH heat sinks represented by the existing national aggregated DH systems can accommodate CBH at a scale that is significant compared to the 2020 renewable transportation target. The possibilities for CBH also depend on its cost-competitiveness compared to, e.g., fossil-fuel-based CHP. The possible expansion of the DH systems by 2020 represents an important opportunity for CBH and is also influenced by the potential increase in the use of other heat supply options, such as, industrial waste heat, waste incineration, and CHP.
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| 6. |
- Braun, Greta, 1995, et al.
(författare)
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Ingenjör4.0 – A National Upskilling Programme to Bridge Industry’s Skill Gap
- 2023
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Ingår i: Procedia CIRP. - Amsterdam : Elsevier. - 2212-8271. ; 120, s. 1286-1291, s. 1286-1291
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Konferensbidrag (refereegranskat)abstract
- Manufacturing industry needs major transformation to meet disruptive environmental, social, and economic challenges, thus requiring a highly skilled workforce. This paper presents key functionalities, results, and best-practices for the launch and operation of a national upskilling platform. The Swedish upskilling programme Ingenjör 4.0's operations have been constantly user-monitored through participant surveys measuring appreciation for training content from the participants and identifying areas with potential for improvement. Thematic analysis of 137 survey responses identified dimensions relevant for an upskilling programme's success. Results show that success factors and hurdles typically lie within the following dimensions: relevance, organization and structure, working life competencies, support from teachers, and collaboration with other learners. The paper concludes that national programmes like Ingenjör4.0 can, in a short time, have deep impact on skill levels for manufacturing industries in areas such as industrial digitalization. Highlighted success factors are: participant appreciation of highly relevant content, collaboration with other participants, highly competent teachers, and the collaboration between universities. Obstacles for the learners are feelings of mismatch in challenges and prior knowledge, lack of feedback and applicable working life examples in the teaching, and the need for increased collaboration with other participants.
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| 7. |
- Byttner, Stefan
(författare)
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Real-time control of an SI engine using ion current based algorithms
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Reducing emissions and improving fuel efficiency in automobiles are today important issues. New sensor techniques are developed to extract detailed combustion information to enable closed loop engine control. This thesis is about a virtual sensor; measuring an ion current inside the cylinder by using the already existing spark plug, followed by signal processing for estimation of combustion parameters. First, the thesis aims to show that the ion current signal can be used for closed loop control of Exhaust Gas Recirculation (EGR). Use of EGR is very common in modern automobiles because of the potential reduction of NOx emissions and fuel consumption, but using too much EGR can have the reverse effect (e.g. increased fuel consumption and driveability problems). Algorithms for estimating combustion variability are proposed and a closed loop scheme for controlling an EGR valve is demonstrated for driving on the highway in a SAAB 9000. Estimation of the pressure peak position is treated for closed loop control of ignition timing. Such estimation can be performed with the ion current but may not work if a fuel additive is used. Different methods are compared and it is shown that using a fuel additive may even improve the estimation accuracy of the pressure peak position with about 25%. An algorithm is also proposed to estimate the pressure peak position even in presence of EGR. Strategies for transient control of the air-fuel ratio are also compared. Air-fuel ratio control is important because even small deviations from the stoichiometric value can result in significantly increased emissions. It is found that a neural network based controller had the best performance with approximately 23% lower RMS error than the adapted standard control module.
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| 8. |
- Johansen, Katinka, et al.
(författare)
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Something is sustainable in the state of Denmark : A review of the Danish district heating sector
- 2022
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Ingår i: Renewable & sustainable energy reviews. - Oxford : Elsevier. - 1364-0321 .- 1879-0690. ; 158
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Forskningsöversikt (refereegranskat)abstract
- This paper provides a coherent review of district heating in Denmark, exploring past, present and future perspectives. Danish district heating is known as unique internationally in terms of heat planning strategies, technical solutions and combinations, energy efficiency and sustainability, ownership models and financing, and it has captured the attention of district heating communities and stakeholders worldwide from the early days. Historically, a ban on landfills incentivised waste incineration, and the strategic integration of combined heat and power plants and recycling of waste heat from industry all increased energy efficiency in the energy system. Ultimately, this contributed to the top World Energy Council ranking of the Danish energy system according to the energy trilemma criteria. A cooperative mind-set, welfare state values and the notions of energy efficiency-, availability-, independency- and sustainability were all pivotal for the evolution of the district heating networks throughout Denmark. Other unique features of the Danish district heating sector include large-scale collective heat planning, the mandatory connection, the non-profit principle, the same approximate price for customers irrespective of heat density, and the relatively high average price of district heating. Moreover, district heating knowledge hubs have led to world-wide exports of district heating technologies and know-how. Future challenges for the Danish district heating sector include increasing biomass import dependency, the changing role of combined heat and power plants in the energy system, transitions to non-combustion heat supplies, and competition from individual heat pumps in single-family houses. However, future ‘smart’ thermal grids will increasingly facilitate sector coupling processes as more renewable energy resources are integrated into the energy system in Denmark and internationally. © 2022 The Authors. Published by Elsevier Ltd.
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| 9. |
- Viktorelius, Martin, et al.
(författare)
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Automation and the imbrication of human and material agency : A sociomaterial perspective
- 2021
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Ingår i: International journal of human-computer studies. - London : Elsevier. - 1071-5819 .- 1095-9300. ; 145, s. 1-11
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Tidskriftsartikel (refereegranskat)abstract
- Automation is projected to transform many industries and work domains and enable both increased levels of safety and efficiency by reallocating many of the functions traditionally performed by operators. However, research on the relation between automation and work practice is lagging and needs to be further explored in order to ground the debate and design of automated work on a sound empirical basis reflecting work in actual organizational settings. In particular, research is needed that offers rich naturalistic representations of human automation interaction that accounts for the mutual shaping of human and material agency over time. The ethnographic workplace study reported in this paper draws on the sociomaterial practice perspective and on the theory of imbrication to analyze a case in which an automatic speed regulation system was installed onboard five large passenger ferries in order to improve the energy efficiency of the execution of voyages. The results show how the adoption, appropriation and use of automated technologies is inextricable from the local patterns of social interaction and collaboration. The study contributes with a deeper understanding of the relation and entanglement of the social and technological elements in human automation interaction.
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| 10. |
- Bhatti, Harrison John, 1979-, et al.
(författare)
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A System Approach to Electrification of Transportation – An International Comparison
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Globally, the transportation system is transforming from a fossil-based to an electrification system. Some countries are leading in the transformation process. Some countries are rapidly catching up to become market leaders in developing and introducing new techniques and equipment that support the transformation process in their countries. In contrast, others are still relying on their old fossil-based system or could not have enough understanding of how to deal with this complex transformation of the transportation system.The electrification of the transportation system is not an isolated system that can be handled as a single technological element. It is a group of multiple technologies, political, societal, and economic sub-systems each of these sub-systems is embedded in each other, forming the whole system. Therefore, it is important to see and manage the system from a holistic perspective to transform the transportation electrification system efficiently. We have selected eight countries from three different continents – Asia (China, India), Australia, which is a country and continent, and Europe (Germany, Norway, Slovenia, Sweden, and the UK) to explore the transformational process of transportation electrification based on each countries’ conditions. We have chosen these continents as they are diversified in adopting transportation electrification system solutions.Our main conclusions are that the political processes and political decisiveness are the most important, followed by the societal and economic, with technology as the fourth. The other three are difficult to obtain without dedicated and determined political decision-makers. Political decision-makers need to use economic means to support the transformation in society and industry to balance the economic disadvantage of electric systems until they pass the cost disadvantage turning point. Technology is no longer a significant barrier as it was about 20 years ago. Now, technology is available, although it can be improved. The important part is to understand how to utilize the existing technology efficiently to transform the old fossil-based transportation system into new electrification of the transportation system. Without clear and strong political support, the industry cannot be expected to initiate, finance, take risks, and take the lead in this global societal transformation.Our analysis shows that China is being positioned as the leading country in the world in the electrification of the transportation system because of the strong technological advancements, control of the entire value chain, strong government decisiveness, and execution power in developing and implementing favorable electric vehicle (EV) policies, the willingness of the public sector to take the lead and citizens support to adopt clean technology. Norway has rapidly become one of the newcomers with large numbers of registered electric vehicles according to its population size within a few years, despite lacking manufacturing electric vehicles (EVs) and equipment for transportation electrification. Germany is leading in the technological sector of transportation electrification within Europe with its prestigious top-selling electric vehicle brands in Germany, such as Volkswagen, Mercedes Benz, BMW, Smart, and Audi, and establishing a battery Gigafactory with an annual potential production capacity of 60 GWh. However, Germany is still lagging behind from the societal perspective of not having enough sales of electric vehicles compared to gasoline-based vehicles. Sweden is a rapidly growing country in the electrification of transport, with three vehicle manufacturers introducing EVs in 2021 and developing electric roads system for more than ten years. Sweden is also working on establishing a new 50 GWh battery manufacturing plant in Gothenburg, Sweden. The UK is also catching up with its other European countries in transforming the transportation system with its strong government support. The British government has kept transportation electrification on its national agenda and considering building a Gigafactory to obtain a position as a future battery leader. However, the UK's adoption rate of electric vehicles is still slow compared to fossil-based vehicles. India, Australia, and Slovenia are far behind in the process of transportation transformation than China, Norway, Germany, Sweden, and the UK. One of the common reasons in all these countries is their governments' baby steps even though they have high ambitions. Their governments require a revolutionized and systems approach to enable remarkable change in the transformation process.
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