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  • 151. Andersson, Agnes
    Battery energy storage systems in Sweden: A national market analysis and a case study of Behrn sport arena2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The renewable energy sources increase the volatility on theelectricity market. To manage the quick variations battery energystorage systems (BESS), together with other storing solutions, willbe required in the future. Depending on which level in the grid thebattery is placed, it can serve different purposes. In this report amarket analysis is conducted, which examine the performance ofbattery storages installed in Sweden. Further on, a simulation, withPV-panels and a battery, was performed at Behrn Arena in Örebro.

    From the market analysis it was shown that the majority of therespondents had used, or will use, their battery for peak shaving.This function is particularly meaningful for customers with a powertariff, which is the case for Behrn Arena. The simulated systemdecreased their yearly cost due to the power tariff with 70 000 SEKand the total electricity bill decreased with 155 000 SEK.

    For the batteries to be more profitable in the future, the batteryprice needs to decrease or the number of revenue streams need toincrease. One revenue with great potential is frequency regulation,which has proven its efficiency in other countries.

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  • 152.
    Andersson, Carl
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Olausson, Linus
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Identifiering av mervärden i EPC-projekt2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this report a study is carried out with the aim to identify added values of EPC projects implemented in schools in order to increase the interest of EPC projects on the market. The report examines how the planned maintenance, supervision, maintenance and corrective maintenance is affected, how insurance premiums and terms are affected, the indoor environment and how the tasks of the operating staff is changing. A literature study of energy savings, energy use in schools, maintenance and insurance as well as how energy efficiency improvements are related to the Swedish environmental objectives has been made. Visits were carried out in Ludvika, interviews were also carried out with operation technicians and local strategists in Ludvika as well as employees of insurance companies.

    Schools often have neglected maintenance and problems with ventilation and indoor environment. Schools also have a large energy saving potential due to their low utilization, mainly because they are empty parts of the year. All Swedish schools could reduce their electricity consumption by 1 TWh per year, which in money equivalents to the salary costs of about 2,000 teaching positions.

    8 schools in Ludvika and 10 schools in Piteå who has completed EPC projects have been studied. The time periods studied are seven years for Ludvika, 2006 – 2012, and for Piteå five years, 2010 – 2014. The data of fault reports and maintenance costs are taken from the municipalities, and descriptions of schools and EPC projects have been received from Caverion who has carried out the EPC projects. Data for maintenance has to some extent been selected in consultation with employees at the municipalities.

    The number of error reports in Piteå schools have shown a slight downward trend with a peak while the EPC project was carried out and one year after. Ludvika has shown an upward trend in maintenance costs, but this is probably due to previously accumulated maintenance. The amount of corrective maintenance is reduced, but only after the project when newly found errors have been fixed and the systems have been properly adjusted. The tasks related to supervisory and maintenance has changed when remote control of systems was installed which leads to a better overview and simplifies troubleshooting. The indoor temperature got more stable, but only after they fixed the weaknesses revealed in connection with the operational optimization. However, there are complaints in Ludvika of low temperatures, but it is caused the target temperature being set too low by the municipality. Insurance is only marginally affected, and only when damage prevention measures are implemented in the properties, which is not done in the studied properties. However, the underlying data sets are too small and over a too small time period to prove any certain changes.

    An added value identified is the ability to use EPC projects as a tool to address deferred maintenance in the real estate portfolio outside the normal budgetary framework while achieving energy savings. 

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  • 153.
    Andersson, David
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Olsson, Philip
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Hur kan en skola med högre energianvändning än det svenska genomsnittet energieffektiviseras?: Energikartläggning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The European Union as a whole is one of the largest energy users and has one of the world's largest greenhouse gas emissions. To reduce global warming, targets have been set to ensure that the average temperature on the earth does not increase more than 2 degrees since the pre-industrial time. Nearly 40% of Sweden's total energy use comes from the building and services sector which in context with that the 2020 targets approaching contributes to the increased need of higher energy efficiency of buildings. Energy audits is a tool for determining what has the greatest potential for saving energy before efficiency measures occurs.

    The thesis includes an energy audit of Trödje primary and middle school, administered by Gavlefastigheter. The study was performed using IDA Indoor Climate and Energy simulation tool. IDA ICE was used to modulate the existing building where all data for the school was included. The vision of the thesis is to investigate how much energy which is possible to save through energy saving measures and which action that is most effective.

    The potential energy saving in the school is high, the school uses 42.6 kWh/m2year more than the average for Gavlefastigheter schools, which corresponds to 21 %. The results show that the complexity of the school and the reconstruction, also called the paviljong, are a major factor in the high energy consumption. The school's energy use has a potential to decrease by 17 %, which did not correspond to the 25 % target set for the work. The work shows that the greatest savings potential exists through the exchange of windows and heat exchangers in the ventilation system, but also that the measures that are assumed to give the greatest savings are not always the most effective.

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  • 154.
    Andersson, Elias
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Enabling industrial energy benchmarking: Process-level energy end-use, key performance indicators, and efficiency potential2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    One of the greatest challenges of our time is global climate change. A key strategy for mitigating the emission of greenhouse gases is the improvement of energy efficiency. Manufacturing industry stands for a large share of global energy end-use but has yet to achieve its full energy efficiency potential. A barrier to untapping this potential is the lack of detailed data on industrial energy end-use at the process level, preventing the development of sound, bottom-up energy key performance indicators (KPIs). This hampers the ability to create a profound strategy for improving industrial energy efficiency because it is not known in which end-use processes the largest energy efficiency potential is to be found. Increasing knowledge about energy end-use at the process level also increases the possibility for energy comparisons, i.e. benchmarking, at the process level.

    This thesis aimed to investigate how to further enable industrial energy benchmarking at the process level, primarily for the pulp and paper and wood industries. Relevant benchmarking requires that data on energy end-use is collected using a common, harmonized categorization of processes and that joint energy KPIs are applied. Therefore, suggestions for standardized categorizations of end-use processes were investigated for the studied industries.

    Based on the calculations, and under the assumptions made in this thesis for estimating the energy efficiency potential of end-use processes, diversity was found between industries around which type of processes have the largest efficiency potential. It also emerged that, due to the lack of detailed data about energy end-use and lack of information about energy efficiency measures, processes accounting for a significant share of the energy efficiency potential in the wood industry risk being overlooked. It is not certain that current energy policies are sufficient to reach the full potential identified. The lack of information about energy end-use and energy efficiency measures implies that neither industrial actors nor policy-makers are able to develop thorough energy strategies or roadmaps for improved energy efficiency.

    While the outcomes of this thesis show that a large share of Swedish pulp and paper mills carry out energy benchmarking to some degree, energy managers emphasized that benchmarking in this particular industry is difficult because it requires a deep understanding of the industry’s heterogenous and integrated processes. This thesis proposes a widened perspective on energy benchmarking and its role in industrial energy management; namely, also considering the process of how energy KPIs are implemented within in-house energy management. A process that enhances energy management includes the continuous monitoring, visualization, and revision of KPIs. In this thesis, a method is developed that encourages the bottom-up implementation of energy KPIs in the pulp and paper industry, which further enables industrial energy benchmarking.

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  • 155.
    Andersson, Elias
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Arfwidsson, Oskar
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Bergstrand, Victor
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    A study of the comparability of energy audit program evaluations2017In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 142, p. 2133-2139Article in journal (Refereed)
    Abstract [en]

    There is a large untapped potential for improved energy efficiency in various sectors of the economy. Governmental industrial energy audit programs subsidizing the companies to conduct an energy audit are the most common policy in trying to overcome the energy efficiency gap. Evaluation studies have been carried out to gain knowledge about the success of a completed energy audit policy program. The evaluations were made in different ways and in addition focused on different performance indicators and used different ways of categorizing data. In this article, a literature review has been made of five evaluation studies from different energy audit programs, where the problems of the present incomparability between programs due to differences are discussed. The policy implication of this paper is that new energy audit policy programs must distinguish a harmonized way of categorizing data, both regarding energy efficiency measures and energy end-use. Further, a proposition for a standard for how to evaluate energy audit policy programs is suggested. Conclusions from this study are that important elements, such as the free-rider effect and harmonized energy end-use data, should be defined and included in evaluation studies. A harmonized standard for evaluating audit programs is not least needed within the EU, where member states are obliged to launch audit programs for large enterprises, and preferably also for small and medium-sized enterprises. This paper serves as an important contribution for the development of such a standard in further research. (C) 2016 Elsevier Ltd. All rights reserved.

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  • 156.
    Andersson, Elias
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Arfwidsson, Oskar
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Benchmarking energy performance of industrial small and medium-sized enterprises using an energy efficiency index: Results based on an energy audit policy program2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 182, p. 883-895Article in journal (Refereed)
    Abstract [en]

    Improved energy efficiency among industrial companies is recognized as a key effort to reduce emissions of greenhouse gases. In this context, benchmarking industrial energy efficiency plays an important part in increasing industrial companies awareness of their energy efficiency potential. A method for calculating an energy efficiency index is proposed in this paper. The energy efficiency index is used to benchmark the energy performance of industrial small and medium-sized companies support and production processes. This enables the possibility to compare the energy performance of single energy end-use processes. This papers proposed energy efficiency index is applied to energy data from 11 sawmills that participated in the Swedish national energy audit program. The index values were compared with each sawmills energy saving potential, as stated in the energy audits. One conclusion is that the energy efficiency index is suitable as an energy strategy tool in industrial energy management and could be used both by industrial SMEs and by governmental agencies with an auditing role. However, it does require a harmonized categorization of energy end-use processes as well as quality assured energy data. Given this, a national energy end-use database could be created to facilitate the calculation of an energy efficiency index. (C) 2018 Elsevier Ltd. All rights reserved.

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  • 157.
    Andersson, Elias
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Dernegård, Henric
    HOLMEN Teknik, SE-114 84, Stockholm, Sweden.
    Wallén, Magnus
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Decarbonization of industry: Implementation of energy performance indicators for successful energy management practices in kraft pulp mills2021In: Energy Reports, E-ISSN 2352-4847, Vol. 7, p. 1808-1817Article in journal (Refereed)
    Abstract [en]

    Energy management is the most prominent means of improving energy efficiency, and improved energy efficiency constitutes the cornerstone in decarbonization. For successful industrial energy management, defining accurate energy performance indicators (EnPIs) is essential. Energy-intensive industries have previously been found to have an improvement potential regarding the current monitoring of EnPIs, especially at process level. While general models for developing and implementing EnPIs exist, manufacturing industries are diverse in terms of their production processes, which is why industry-tailored models for EnPI development are needed. One major outcome of this paper is a unique model specifically tailored for kraft pulp mills. The model derives from a practice-based approach for EnPI development, building on real-life experiences from a Swedish group of companies. This paper’s developed model, and the validation of the EnPIs, further increase the understanding of the kraft pulp industry’s processes and how to apply descriptive and explanatory indicators. The developed model can potentially be generalized to other sectors.

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  • 158.
    Andersson, Elias
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Karlsson, Magnus
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Paramonova, Svetlana
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Energy end-use and efficiency potentials among Swedish industrial small and medium-sized enterprises - A dataset analysis from the national energy audit program2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 93, p. 165-177Article, review/survey (Refereed)
    Abstract [en]

    Improving energy efficiency in industry is recognized as one of the most vital activities for the mitigation of climate change. Consequently, policy initiatives from governments addressing both energy-intensive and small and medium-sized industry have been enacted. In this paper, the energy end-use and the energy efficiency potential among industrial small and medium-sized companies participating in the Swedish Energy Audit Program are reviewed. The three manufacturing industries of wood and cork, food products and metal products (excluding machinery and equipment) are studied. A unique categorization of their production processes energy end-use is presented, the results of which show that the amount of energy used in various categories of production processes differ between these industries. This applies to support processes as well, highlighting the problem of generalizing results without available bottom-up energy end-use data. In addition, a calculation of conservation supply curves for measures related to production processes is presented, showing that there still remains energy saving potential among companies participating in the Swedish Energy Audit Program. However, relevant data in the database used from the Swedish Energy Audit Program is lacking which limits the conclusions that can be drawn from the conservation supply curves. This study highlights the need to develop energy policy programs delivering high-quality data. This paper contributes to a further understanding of the intricate matters of industrial energy end-use and energy efficiency measures.

  • 159.
    Andersson, Elias
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Key performance indicators for energy management in the Swedish pulp and paper industry2019In: Energy Strategy Reviews, ISSN 2211-467X, E-ISSN 2211-4688, Vol. 24, p. 229-235Article in journal (Refereed)
    Abstract [en]

    The pulp and paper industry is one of the five most energy-intensive industries world-wide. In Sweden, most pulp and paper mills were certified with a standardized energy management system already in 2005. As Swedish mills have more than a decade of experience with energy management systems and energy key performance indicators (KPIs), studying KPIs within Swedish pulp and paper mills will enable both a state-of-the-art positioning of best-practice in relation to energy KPIs in pulp and paper mills, but also spot potential barriers and drivers in the utilization of energy KPIs. This paper studies the current level of implementation and operationalization of energy-related KPIs in the Swedish pulp and paper industry. The results show a potential for improvement.

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  • 160.
    Andersson, Elin
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Use cases and Business Models: Urban Smart Grid2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The EU has established a climate and energy package that includes solutions of the threatening climate changes and is called the 202020 package. The goal is to reduce the greenhouse gases with 20 % until the year 2020. The energy use should be lowered with20 % and the energy efficiency will be 20% higher.

    On account of this, Stockholm city is developing a new city district which is called Stockholm Royal Seaport. The vision of Stockholm Royal Seaport is to develop a sustainable city district that should contribute to innovation, development and promotion of the Swedish environmental technology. Through a new and more efficient grid, Smart Grid, the total energy usage will be lowered, the load optimized and it will be possible to connect decentralized electricity recourses as well as integrate electric vehicles. To make the Smart Grid implementation as good as possible use cases have been a big part of the preparatory work. A use case is a document consisting of one or several scenarios that describe how actors, who could be a human or a piece of hardware, interact with the system to reach a specific goal.

    This master thesis has been performed at and assigned by Fortum. The aim of the study was to deliver ideas and suggestions for new markets and business models and create new incitements, which will be needed to succeed with the implementation of Smart Grid; this will be done especially with regards to sustainable development. During the project around 170 existing use cases were organised depending on which area in the grid they belonged to. This was done so that an area in Stockholm Royal Seaport could be picked out to be deeper analysed. The use cases concerning the integration and use of the electric vehicle went through a closer study to evaluate what changes are needed in management, regulation etc., in order to success with the development of the new grid. The "new" aim of this study became to show the differences in how much carbon dioxide the electric vehicle emits and how much its owner pays in taxes compared to a regular vehicle. The two vehicles that have been compared are both from Renault. The emissions from the electric vehicle are considerate to be equal to the emission from production of the used electricity. The emissions have been calculated using historical electricity production data together with a production forecast of the year of 2020. The outcome of the calculations differs depending on if the vehicle "uses" the total production mix or the electricity produced on the margin. The results show that the electric vehicle pays a third less in taxes: if one looks at the total costs for the vehicles, the investment of the electric vehicle has a payback time of ten years. Substitute a conventional vehicle for the electric vehicle reduces the carbon dioxide emissions between 0,54 and 1,67 ton a year. This indicates that a differentiated carbon dioxide tax would be favouring the electric vehicle and also makes one pay for what one emits.

  • 161. Andersson, Elinda
    Vidareutveckling av metod för bedömning av miljöpåverkan i samhällsekonomiska analyser vid investeringar i det svenska elstamnätet2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Svenska kraftnät, which is the authority responsible for the Swedish national grid, performs cost-benefit analysis (CBA) to assess which of different investment projects that are of greatest benefit to society. The environmental impacts are also estimated during this analysis. In this paper, a tool for estimating the environmental impacts during the lifetime of a grid component has been developed with the purpose of enabling a more complete environmental evaluation. A life cycle assessment was performed to develop the tool. The impact categories that have been studied are climate change (kg CO2-eq), freshwater eutrophication (kg P-eq), particulate matter formation (kg PM10-eq) and terrestrial acidification (kg SO2-eq). To be able to compare the environmental effects with other costs and benefits in the CBA a monetary valuation of the impact categories has been established. The result of this paper indicates that the AC-overhead line is the technology that contributes with the lowest environmental impact during the life cycle. This result, however, is obtained when analyzing different technical alternatives with the same preconditions, which rarely is the case in real projects. The result can therefore differ between different investment projects. The tool enables an assessment of the environmental impacts of different investment projects in the Swedish national grid, and is therefore an important part of the cost-benefit analysis to determine which alternative is best suited. 

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  • 162.
    Andersson, Ellen
    Mälardalen University, School of Business, Society and Engineering.
    Nära-nollenergibyggnader: En fallstudie av ett flerbostadshus förutsättningar att klara Boverkets framtida krav2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In order to develop energy-efficient constructions all new buildings will be nearly-zero energy buildings by year 2021. A nearly-zero energy facility is a building with high energy performance and very low energy consumption, where the amount of energy that needs to be supplied to the building will largely originate from renewable sources that are often self-produced on site or nearby. On December 15, 2016 BFS 2016: 13 - BBR 24 was introduced with requirements for verification of the building's specific energy use. The new regulations for nearly-zero energy buildings will be introduced in two stages through BBR (A) and BBR (B). BBR (A) implies no aggravation of requirements, but introduces a new way of calculating the energy performance of the building measured in primary energy. Primary energy factors are introduced per energy carrier, where the energy carrier for electric heating receives a higher value then other energy carriers. A projected five-storey apartment building located in Sigtuna, Stockholm has been investigated and energy calculations and simulations have been carried out in the energy calculation program IDA Indoor Climate and Energy. Simulations have been carried out on a reference object, focusing on analyzing how the energy utilization of the building is affected by various actions. The measures investigated are energy supply and origin of this, changes in the building construction and technical systems. The result shows that with relatively small changes the required demands of close-zero energy buildings can be reached. Changes to the building construction through better exterior wall insulation, better U-values ​​of building constructions and increased efficiency of heat exchanger, make demands for near-zero energy buildings in BBR (B). With self-produced electricity via solar cells the primary energy for the building will be even lower. The hardest challenge comes for the electricity heated buildings which due to an increased primary energy factor, will get harder to meet the future requirements due to a higher demand level.

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  • 163.
    Andersson, Emil
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Småskalig elproduktion i urban miljö: Fallstudie av elproducerande system på ett handelscentrum2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates if a system for small scale electricity production located in anurban environment can be profitable. The work has been divided up into two parts,one extensive literature study and one case study. The purpose of the literature studywas to investigate the area, resulting in a choice of which technology to be studied indepth in a case study.In the case study a system containing small scale wind turbines and photovoltaicsmounted on Gränby Centrums roof was examined. From data containing wind power,wind direction and total irradiation, possible production from a system weresimulated. Three products of each technology were examined in the simulations.From the simulated production an economic analysis was carried out, this toinvestigate if a system is profitable. The two alternatives that showed the besteconomic result formed the optimal system.The economic analysis showed that none of the investigated alternatives whereprofitable, this because the capital costs exceeded the revenues. The revenues fromthe wind turbines were low because of the poor wind conditions in an urbanenvironment and the revenues from the photovolatics were low because of the lowelectricity price.

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  • 164.
    Andersson, Emma
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems.
    Abrahamsson Bolstad, Maja
    Linköping University, Department of Management and Engineering, Energy Systems.
    Hosting Capacity Methods Considering Complementarity between Solar and Wind Power: A Case Study on a Swedish Regional Grid2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The demand for electrical power is growing due to factors such as population growth, urbanisation, and the transition from fossil fuels to renewable energy sources. To be able to keep up with the changes in electricity demand, the Swedish power grid must connect more renewable power generation, but also  increase its transmission capacity. Traditionally, power grids are expanded to increase the transmission capacity which requires a lot of time and investments. In order not to hinder the electrification of society, it is important to adequately estimate the current transmission capacity and plan the expansions accordingly. In the past, the generation of electrical power was primarily based on dispatchable energy sources, and the planning of new connections to the grid was assessed according to the stable and controllable nature of the electricity supply. However, renewable sources like solar and wind power are affected by weather variations. Therefore, the traditional methods of planning the power grid are no longer sufficient. Instead, there is a need to develop and implement new methods that account for the variable nature of renewable energy sources, and also the possible complementarity between different renewable power sources. This can possibly allow more connection of renewable power generation to the grid, without the need of expanding it.

    The aim of this thesis is to investigate two different methods for analysing how much renewable power generation that can be connected to the power grid, so-called hosting capacity methods. The first method is a deterministic method which is traditionally used in power system analyses since it is a fast, simple and conservative method. This method does neither consider the intermittent nature of solar and wind power, nor any complementarity. The second method is a time series method which considers the complementarity and intermittency of solar and wind power but requires much data. The methods are compared in regards to assessed hosting capacities, risks and reliability of results.

    The study is performed on a regional grid case in the middle of Sweden. Solar and wind power plants with different capacities are modeled at ten buses in the power grid. The power grid is analysed in PSS/E with loading of lines and voltage levels determining the assessed hosting capacities. A correlation map presenting the temporal correlations of solar and wind power over the grid case area is also created in order to evaluate the complementarity in the area and its possible effects on the assessed hosting capacities. 

    The results show that the time series method is more reliable than the deterministic method. This is due to the difficulties in identifying accurate worst case hours that are used for the deterministic method. The time series method is also preferred as it considers complementarity between solar and wind power. However, the correlation map argues that the grid case area has weakly positive correlations, meaning low complementarity between solar and wind power. This suggests that the differences in hosting capacity between the two methods are more likely dependent on the temporal variations in existing load and power generation. The differences in assessed hosting capacity between the ten buses in the power grid are probably not due to the local complementarity either, but rather the structural differences of the grid in terms of components, local loads and existing power generation.

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    Hosting Capacity Methods Considering Complementarity
  • 165.
    Andersson, Erik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utvärdering av möjligheten att tillvarata energi ur processvatten: En undersökning gjort vid Olofsfors AB på uppdrag av UMIA AB.2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it’s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C. This is done by disposal of hot water from the pit to the river outside while new, cold water, from the river is pumped into the pit. The hot water that is being disposed of contains energy that has not at all been utilized, this has led to the purpose of this report which is to examine the possibility to utilize parts of the energy in the water.

     

    Two possible outlets for the energy at the plant has been selected as especially interesting: • Heating of ventilation supply air in two units with low thermal efficiency and relatively high airflows where the supply air temperature is to be increased from 9 °C to 15 °C. • Fan heaters installed with electric batteries of approximately 200 kW capacity, which heats the premises and serves as an air barrier at the intake ports for metal.

     

    Calculations of power available in one of the factory pump pits during the heating season from October to May and the power required for deposition areas were made. The result obtained is illustrated by means of duration charts from which required and available energy is deduced.

     

    The result of this:

    Pump pit                             887 MWh / October to May

    Ventilation                          642 MWh / year

    Fan heaters                         515 MWh / year

     

    A draft measure has been developed in which two heat pumps delivers hot water for heating of both the ventilation supply air and liquid batteries in air fan heaters. This measure proposal means a cost saving of approximately 390 000 SEK / year where pay-off time of the investment is approximately 5 years.

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  • 166.
    Andersson, Erik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Wengberg, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Utvärdering av konsekvenserna för nätanslutning av vindkraftparker i Sverige vid införandet av nätkoden Requirements for Generators2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Grid codes are becoming more demanding on power generating units due to the factthat the complexity of the power grid is increasing. The penetration of wind powerhas grown over the last years and it is clear that wind farms need to be addressedwith the same type of grid codes as conventional generation units. There is howeveran undeniable difference between the technology in conventional synchronousgeneration units, and the asynchronous generation units in wind farms.

    This thesis has reviewed the current grid code in Sweden and compared it to the newcode proposed by ENTSO-E, “the Requirements for Generators”, in the aspect ofwind farms with an installed power of 30 MW or more. The comparison has beencomplemented by an analysis of how wind farms of two different technologies(Doubly fed induction generators and full power converters) can meet therequirements and technical proposals have been given on how to be able to meetcompliance with the new grid codes.

    The Requirements for Generators contains many non-exhaustive and optionalrequirements, because of this it has been difficult to, at this stage, exactly point outthe technical impact on the grid connection of future wind farms in Sweden. For manyof the requirements in the Requirements for Generators there is no equivalent in theSwedish Grid Code (SvK FS2005:2) but counterparts can thus be found in existingpractices and therefor does not imply any major differences for the industry.

    The requirements of frequency regulation, synthetic inertia and reactive powercapability are the main components of the RfG which will require additional softwareand hardware installations for future wind farms in Sweden.

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  • 167.
    Andersson, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Energianvändning för att överkomma visköst motstånd i material vid pelleteringsprocesser: Metodutveckling för kontinuerlig pelletering i singelpelletpress2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att motverka global uppvärmning är det centralt att världen rör sig från fossila bränslen för energiproduktion och mot alternativa energiresurser som biobränslen. Industriella restprodukter – exempelvis sågspån – är ett bra alternativ för framställning av biobränslen då annars oanvändbara material kommer till användning. För att göra sådana material mer lätthanterliga komprimeras de ofta till pellets. Den globala pelletsmarknaden har ökat med ungefär 14 % årligen sedan 2010.

    Pelleteringsprocessen kan delas upp i tre faser: komprimering, strömning och friktion. Energianvändningen i pelleteringsprocessen går till komprimering av materialet; till att deformera materialet och överkomma det viskösa motståndet; och till att överkomma friktionen mellan materialet och presskanalväggarna. För att undersöka energianvändningen för pelletering på laboratorieskala används ofta singelpelletpressar.

    Syftet med den här studien är att öka kunskapen kring energianvändningen vid pelletering, med det huvudsakliga målet att vidareutveckla test- och beräkningsmetoder för att bestämma energianvändningen för att överkomma det viskösa motståndet i materialet vid pelletering i singelpelletpress.

    Materialet som pelleterades i studien var granspån. För att bestämma energianvändningen till att överkomma det viskösa motståndet i materialet etablerades ett jämviktssystem i singelpelletpressen, där presskraften stabiliserades med successiva pressningar – kallat kontinuerlig pelletering. Matrisuppställningen i singelpelletpressen inkluderade en kona, där materialet tvingas ner från en presskanal med en större diameter till en presskanal med en mindre diameter för att inkludera strömningsfasen. För att uppnå ett jämviktstillstånd kontrollerades friktionsmotståndskrafterna mot strömning av materialet genom att variera längden på den aktiva presskanalen (där det komprimerade materialet under konan har kontakt med presskanalväggen). Tillfället då strömning initierades undersöktes för att separera komprimeringsfasen från strömnings-/friktionsfasen. Separata komprimerings- och friktionsförsök gjordes för att subtrahera energianvändningen till komprimering och till att överkomma friktion från den totala energianvändningen – för att komma åt energianvändningen till att överkomma det viskösa motståndet.

    Jämviktstillståndet nåddes och kontinuerlig pelletering utfördes med en materialfukthalt på 17,5 % och en aktiv presskanallängd på 13 mm, där det högsta uppmätta presstrycket för varje successivt försök stabiliserades runt 154 MPa och pellets med densiteten 1200 kg/m3 producerades. Medelvärdet på trycket som krävdes för att initiera strömning blev 123 MPa. Den specifika energianvändningen som gick till att överkomma materialets viskösa motstånd blev 88 J/g material, vilket motsvarade 65 % av den totala energianvändningen.

    Motståndskrafterna mot presskraften från friktionen mellan pelleten och presskanalväggen ökade exponentiellt i förhållande till längden på pelleten i den aktiva presskanalen, vilket innebär svårigheter med att etablera önskade jämviktstillstånd genom en enbart teoretisk bestämning av den aktiva presskanallängden; experimentella försök behöver alltså göras.Den kontinuerliga pelleteringen i studien gjordes vid ett lägre presstryck än vid industriella processer för att inte överbelasta utrustningen. Densiteten för pelleten som tillverkades hamnade dock inom industriella intervall, vilket validerar metoden i studien. För att undersöka jämviktstillstånd vid högre presstryck kan längden på den aktiva presskanalen ökas.

    Metoden i studien förenklar vissa aspekter av kraftförhållanden och strömningens egenskaper. Vidare studier rekommenderas angående Poissoneffekten i konan, visköst motstånd i materialet i den aktiva presskanalen som konsekvens av en ojämn hastighetsprofil och en potentiell övergångsfas mellan komprimeringsfasen och strömnings-/friktionsfasen.

    Studien visar att kontinuerlig pelletering i singelpelletpress fungerar och för framtida studier på energianvändningen vid pelletering som använder singelpelletpressar rekommenderas att en uppsättning matriser med olika längder på den aktiva presskanalen konstrueras för att enkelt kunna upprätta ett jämviktstillstånd för kontinuerlig pelletering. Att andelen av den totala energianvändningen som gick till att överkomma det viskösa motståndet i materialet blev så hög belyser vikten av fortsatta studier kring det viskösa motståndet för att vidare kunna energieffektivisera pelleteringsprocessen.

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  • 168.
    Andersson, Gustav
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Ericsson, Emil
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Dark Ages Interferometer (DALI) Deployment Rover: Energy System2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The cosmic “Dark Ages” is the cosmic era between the epochs of recombination of cosmic microwave background and the formation of the first stars. The only signal from this epoch is from neutral hydrogen, which could represent one of the richest data sets in cosmology. In order to extract this data, NASA/JPL has proposed a rover mission to the farside of the moon to deploy several radio arrays. Here the arrays would gather data undisturbed by human interference. This thesis examines the possibility of using photovoltaic and electric batteries as an energy solution for a rover on the moon. The requirement for such a system to survive on the moon is discussed in a literature study. A proof of concept simulation using a Simulink model has also been done. The thesis concludes that a rover can deploy the radio array using solar energy. It would be able to hibernate through the night using radioisotope heating. It would need to wait for its batteries to charge before each night.

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    DALI Energy System
  • 169.
    Andersson, Harald
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Moshfegh, Bahram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology. Linköpings universitet.
    A numerical and experimental investigation of a confluent jets ventilation supply device in a conference room2022In: Energies, E-ISSN 1996-1073, Vol. 15, no 5, article id 1630Article in journal (Refereed)
    Abstract [en]

    In this study, confluent jets ventilation (CJV) supply devices with three different nozzle arrays (1 × 19, 2 × 19, 3 × 19) were investigated both numerically and experimentally at two different airflow and supply air temperature set-ups. The performance of the CJV supply devices was investigated concerning thermal comfort, indoor air quality (IAQ), and heat removal effectiveness in a conference room environment. A comparison between the experimental and numerical results showed that the v2−f model had the best agreement out of the investigated turbulence models. The numerical results showed that the size of the array had a great impact both on near-field development and on the conditions in the occupied zone. A larger array with multiple rows and a lower momentum conserved the inlet temperature and the mean age of the air better than a single-row array with a higher momentum. A larger array with multiple rows had a higher IAQ and a greater heat removal effectiveness in the occupied zone because the larger array conserved the mean age of air better and the buoyancy driven flow was slightly better at removing the heat. Because of the lower inlet velocities, they also had lower velocities at ankle level, which decreased the risk of draft and thermal discomfort.

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  • 170.
    Andersson, Harald
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Moshfegh, Bahram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Energy-Saving Measures in a Classroom Using Low Pressure Drop Ceiling Supply Device: A Field Study2016In: 2016 ASHRAE Winter Conference Papers, ASHRAE, 2016Conference paper (Refereed)
    Abstract [en]

    Between 1990 and 2006 the energy use by ventilation systems in Swedish schools doubled. This is explained by high airflows in schools because of the high occupant density. Studies show that 87% of Swedish schools use constant air volume (CAV), and it is estimated that a change to variable air volume (VAV) could save 0.12-0.33 TWh (4.1*10(12) - 1.1*10(13) Btu) per year. Therefore the aim of this study is to investigate whether it is possible to replace displacement ventilation (DV) with mixing ventilation (MV) to create a comfortable indoor climate in a typical classroom and at the same time decrease the energy use by using VAV and Low Pressure Drop Ceiling Supply Device (LPDCSD). The study used two LPDCSDs which consist of circular channels with 190/228 round jets placed in an interlocking pattern, with a horizontal one/two-way-direction. The field study was carried out in a school which is intended to be extensively renovated. The school currently has DV and CAV. The study was carried out by installing MV with LPDCSD in one of the typical classrooms. Several different air-flow rates were investigated using tracer-gas technology to measure the local mean age of the air in the occupied zone. Simultaneously, thermal comfort and vertical temperature gradients were measured in the room. The results show nearly uniform distribution of the local mean age of air in the occupied zone, even in the cases of relatively low air-flow rates. Since the mixing of air is more or less the same in the entire occupied zone VAV can be used to reduce air-flow rate based on the desired CO2-level. Because of the number of students in each classroom and the fact that changes in air-flow rates have no significant effect on the degree of mixing, it is possible to reduce the air-flow rates for extended periods of time. Finally, since the LPDCSD has a lower pressure-drop than the currently used supply devices and it is possible to use VAV to lower the airflows in cases with reduced heat loads, it is possible to significantly reduce the energy usage in the school while maintaining the IAQ, increasing the thermal comfort and the available floor area of the occupied zone.

  • 171.
    Andersson, Hedda
    Karlstad University.
    El-och värmeenergibehov för skolor: Beräknade och uppmätta värden för 4 skolor i Stockholm2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As buildings are built more and more energy-efficient, precision of energy calculations needs to increase as the error decrease and the requirement to calculate “correctly” increases. At the beginning of a construction project, a builder must show that the building will comply with the National Board of Housing, Building and Planning's regulations when the project is completed in order to start the project. When the building is finished, it is tested through different feeds to investigate whether the building meets the requirements that the builder has claimed in the design step. The difficulty of calculating the energy requirement of a building so that it corresponds to the measured energy requirement is well known in the construction industry. In a school, heating of premises and tap water accounts for two thirds of the energy use and one third consists of lighting, kitchens and fans for ventilation. In a study with 7 newly built Swedish schools calculated and measured energy was examined, it was found that calculated and measured energy needs differed between -44% to + 28%. 

    To make it easier to produce calculations of schools energy needs that correspond to real energy needs, this report examines which parameters are important for a school's energy needs and which parameters that makes the calculated and measured energy needs differ profoundly. Two preschools and two primary schools were examined in this study. A calculation model was built to examine which parameters have the greatest impact on a school's energy needs and to calculate the schools' energy needs. 

    The measured and estimated heat energy requirements in the examined schools had a deviation of -3% and -16%. The measured and calculated electricity energy needs in the schools had a deviation of -2% and + 28%. The parameters that were important when calculating a school's energy needs turned out to be the efficiency of ventilation, tap water consumption, g-value, room temperature, supply air temperature, operating time of ventilation, operating time of commercial kitchens and electricity requirements for commercial kitchens. 

    The result showed that when making energy calculations and trying to adjust and match it as closely as possible to the real measured values, the parameters with the most impact on this were efficiency of ventilation, g-value, supply air temperature, electricity demand for the commercial kitchen and the operating times of both the ventilation and the commercial kitchen. 

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  • 172.
    Andersson, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Application of Liquid Hydrogen Carriers in Hydrogen Steelmaking2021In: Energies, E-ISSN 1996-1073, Vol. 14, no 5, p. 1392-Article in journal (Refereed)
    Abstract [en]

    Steelmaking is responsible for approximately one third of total industrial carbon dioxide (CO2) emissions. Hydrogen (H2) direct reduction (H-DR) may be a feasible route towards the decarbonization of primary steelmaking if H2 is produced via electrolysis using fossil-free electricity. However, electrolysis is an electricity-intensive process. Therefore, it is preferable that H2 is predominantly produced during times of low electricity prices, which is enabled by the storage of H2. This work compares the integration of H2 storage in four liquid carriers, methanol (MeOH), formic acid (FA), ammonia (NH3) and perhydro-dibenzyltoluene (H18-DBT), in H-DR processes. In contrast to conventional H2 storage methods, these carriers allow for H2 storage in liquid form at moderate overpressures, reducing the storage capacity cost. The main downside to liquid H2 carriers is that thermochemical processes are necessary for both the storage and release processes, often with significant investment and operational costs. The carriers are compared using thermodynamic and economic data to estimate operational and capital costs in the H-DR context considering process integration options. It is concluded that the use of MeOH is promising compared to the other considered carriers. For large storage volumes, MeOH-based H2 storage may also be an attractive option to the underground storage of compressed H2. The other considered liquid H2 carriers suffer from large thermodynamic barriers for hydrogenation (FA) or dehydrogenation (NH3, H18-DBT) and higher investment costs. However, for the use of MeOH in an H-DR process to be practically feasible, questions regarding process flexibility and the optimal sourcing of CO2 and heat must be answered

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  • 173.
    Andersson, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Non-geological hydrogen storage for fossil-free steelmaking2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the last half-century, global steel use has increased more than threefold and further growth is expected, particularly in developing economies. However, steelmaking is currently responsible for 7% of the global net carbon dioxide (CO2) emissions, and any substantial further optimization of existing processes that utilize fossil fuels for iron ore reduction is infeasible. Therefore, steelmaking must change for climate change mitigation targets to be achievable. Hydrogen (H2) steelmaking using H2 produced via electrolysis is one way forward. A challenge is the substantial electricity demand of electrolysis. H2 storage may lower the electricity cost of electrolysis by allowing a larger share of H2 to be produced when the electricity price is low. Existing experience with large-scale H2 storage is limited to salt caverns and the construction of such caverns requires suitable geological formations, which are neither ubiquitous nor well-distributed. However, geologically-independent H2 storage technologies have not previously been evaluated for integration with H2 steelmaking. This is the aim of this thesis. H2 storage technologies were reviewed and liquid H2 carriers were identified as the most techno-economically feasible non-geological options. Out of these liquid carriers, methanol (CH3OH) was found particularly promising for H2 steelmaking due to the low heat demand of its dehydrogenation, its low-cost storage, and the high technological readiness of plants for both its production and dehydrogenation. A complete CH3OH-based H2 storage concept was developed, including processes for CO2 and heat supply. Its ability to reduce the H2 production cost in a H2 steelmaking process was evaluated via a deterministic optimization method based on historical electricity prices. Results indicate that CH3OH-based storage may be competitive with geological storage options, especially for cases with long-duration electricity price patterns.  The option to also sell off accumulated CH3OH from the storage was investigated. Such steel and CH3OH co-production may improve storage utilization and reduce the risk of investment into H2 storage as it allows for profitability to be reached under a more diverse set of electricity market conditions.

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    Kappa
  • 174.
    Andersson, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Krüger, Andries
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Grönkvist, Stefan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Methanol as a carrier of hydrogen and carbon in fossil-free production of direct reduced iron2020In: Energy Conversion and Management: X, ISSN 2590-1745, Vol. 7, no 100051Article in journal (Refereed)
    Abstract [en]

    Steelmaking is responsible for around 7% of the global emissions of carbon dioxide and new steelmaking processes are necessary to reach international climate targets. As a response to this, steelmaking processes based on the direct reduction of iron ore by hydrogen produced via water electrolysis powered by renewable electricity have been suggested. Here we present a novel variant of hydrogen-based steelmaking incorporating methanol as a hydrogen and carbon carrier together with high-temperature co-electrolysis of water and carbon dioxide and biomass oxy-fuel combustion. The energy and mass balances of the process are analyzed. It is found that this methanol-based direct reduction process may potentially offer a number of process-related advantages over a process based on pure hydrogen, featuring several process integration options. Notably, the electricity and total energy use of the steelmaking process could be reduced by up to 25% and 8% compared to a reference pure-hydrogen process, respectively. The amount of high-temperature (>200 °C) heat that must be supplied to the process could also be reduced by up to approximately 34%, although the demand for medium-temperature heat is substantially increased. Furthermore, the suggested process could allow for the production of high-quality direct reduced iron with appropriate carburization to alleviate downstream processing in an electric arc furnace, which is not the case for a process based on pure hydrogen.

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  • 175.
    Andersson, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Bernström, Vendela
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Törnqvist, Joacim
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Hosting Capacity of a Low-Voltage Grid: Development of a Simplified Model to be used in future Solar Roadmaps2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this bachelor thesis is to assess whether it is possible to create a simplified model that estimates the hosting capacity of a low-voltage grid. The Simplified model is compared with a more elaborate model created by the Built Environment Energy Systems Group (BEESG) at Uppsala University. The Simplified model takes three easily obtainable variables into account. The model created by BEESG allows us to observe both the amount of photovoltaic (PV) power that is installed as well as the voltages in each bus in a grid. The hosting capacity is found by gradually increasing the amount of PV power installed in a low-voltage grid until overvoltage is reached. Simulations with BEESG’s model are done for a week in July when the PV generation has its peak and the load is generally low. The Simplified model is created using linear regression with the calculated values from the BEESG’s model as a reference. The report shows that the Simplified model will give an estimation of the low-voltage grid’s hosting capacity that is comparable to the value calculated with BEESG’s model. The results show that it is rarely the low-voltage grid that restricts the installation of PV facilities and that a high self-consumption is advantageous regarding to the grids hosting capacity.

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  • 176.
    Andersson, Maria
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Cooperation in local electricity markets: modelling of technical measures1997Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis presents a system analysis for co-operation in local electricity markets including distributors and customers. The purpose of co-operation is to minimise the system cost of local markets by introducing system measures, such as end-use measures and municipal co-generation plants. Co-operation will strengthen the position of local markets in the national as well as future international electricity markets. With end-use measures local markets will achieve flexibility, additional reserve capacity and ability to avoid sudden large costs for peak loads. Biomass-fired cogeneration plants can become of great importance in an international market. In Sweden there is a simultaneous demand for electricity and district heating, many local markets already include district heating systems and there are major forest areas which can contribute with renewable fuel. The system analysis is partly based on the simulation model (INDSIM) and the linear programming model (MODEST). The simulation model has been further developed (STRATO) to include calculation of system costs. Shadow price analysis has been developed in order to study incentives for system measures. Calculation procedures have been developed that describe cooperation between distributor and customer. Six case studies of a selection of real, existing local markets in Sweden are presented. The studies show the potential economical effects of co-operation measured by system costs and shadow prices. Co-operation has been considered between demand- and supply-side, electricity- and district heating systems and also between different time periods. In a typical local market with 90 000 inhabitants, if end use measures are introduced without cooperation the system cost of the distributor will increase by 14 million SEK for a time period of 25 years. If instead end-use measures are introduced in co-operation, together with a biomass-fired cogeneration plant, the system cost of the local market will be reduced by 444 million SEK. Furthermore, the use of biomass in the local market is increased from 36 to 72 % while the use of oil is decreased from 34 to 1%. Another case study of another local market (50 000 inhabitants) shows that end-use measures will reduce the system cost (excluding investment costs) of an industry by 50 % corresponding to 1.3 million SEK for one year. The end-use measures imply reduced power demand during peak load periods in the local market and increased power demand during non- peak load periods.

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  • 177.
    Andersson, Maria
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Cost-effective incentives for local electric utilities and industries in co-operation: modelling of technical measures1993Licentiate thesis, monograph (Other academic)
    Abstract [en]

    In the Swedish electricity system there is a great potential for increasing the cost efficiency of the electricity use. However, today the economic incentives, offered for instance by existing electricity rates, are too weak to improve the use of the system. On the Swedish electricity market there are, at least, three different actors, the power producer, the distributor and the customer. Today these actors act separately due to low awareness of the costs for electricity generation, over the year and the day. If the actors are aware of the real electricity costs, cost-effective incentives will arise to introduce energy system measures that will reduce the energy system cost considerably. The thesis presents two energy system analyses of an existing Swedish municipality. The first analysis deals with the introduction of industrial end-use measures, with the local utility’s existing electricity rates as boundary conditions. The analysis is carried out with a simulation model for electricity use in industries. The second analysis deals with the introduction of energy system measures, on the municipal supply-side and demand-side, when the local electric utility and the customers are regarded as one system. The analysis is carried out with an optimization model, that is based on linear programming. The results show that if 17 industries introduce end-use measures, with the existing electricity rates as boundary conditions, their energy system costs will be reduced by 12 MSEK for a time period of 10 years, whereas the local utility will increase its energy system cost by 6 MSEK. However, if there is a co-operation between the local electric utility and the customers, their joint energy system cost will be reduced by 330 MSEK for a time period of 10 years.

  • 178.
    Andersson, Maria
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Shadow prices for heat generation in time-dependent and dynamic energy systems1994In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 19, no 12, p. 1205-1211Article in journal (Refereed)
    Abstract [en]

    Shadow prices for heat generation are used to study the impact of changes in heat demand on the total system cost of an existing district-heating system in Sweden. The energy system may be considered to be both dynamic, because there is energy storage, and time-dependent since the electricity tariff is time-differentiated and the heat demand varies over the year and day. The energy system has been analysed with and without energy storage. The analysis shows that despite a reduction in system cost, the use of energy storage can result in higher shadow prices for heat generation in some time periods.

  • 179.
    Andersson, Maria
    et al.
    Linköping University.
    Björk, C.
    Linköping University.
    Karlsson, Björn
    Linköping University.
    Energy system cost reduction as a result of end-use measures and the introduction of a biomass-fired co-generation plant1993In: International Conference on Renewable Energy - Clean Power 2001: 17-19 November 1993, London, London: Institution of Electrical Engineers (IEE), 1993, no 385, p. 37-42Conference paper (Refereed)
    Abstract [en]

    This paper will describe an energy system analysis of an existing Swedish municipality of 90 000 inhabitants. The analysis, which is performed by using an optimization model will show what energy system measures that should be introduced to minimize the total energy system cost. In the existing municipality a local utility distributes heat, for the district heating system, and electricity. The heat is generated by the utility and the electricity is purchased from a large power producer.

  • 180.
    Andersson, Maria
    et al.
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Björk, Curt
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Karlsson, Björn
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Cost-effective energy system measures studied by dynamic modelling1993In: 2nd International Conference on Advances in Power System Control, Operation and Management, APSCOM-93., London: Institution of Electrical Engineers (IEE), 1993, Vol. 1, p. 448-455Conference paper (Refereed)
    Abstract [en]

    In a national electricity system there often exists a great potential for increasing the cost-efficiency of the electricity use. However, if the economic incentives for improving the use of the system are too weak, it is most likely that this potential will not be utilised. If electricity tariffs reflect real electricity costs, over the year and the day, cost-effective incentives will arise for introducing energy system measures that will reduce the energy system cost considerably. This paper presents two energy system analyses of an existing Swedish municipal energy system. The analyses are carried out with a simulation model for electricity use in industrial energy systems, and an optimisation model that is based on linear programming.<>

  • 181.
    Andersson, Maria
    et al.
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Karlsson, Björn
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Cost-effective incentives for cooperation between participants in the electricity market1996In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 54, no 4, p. 301-313Article in journal (Refereed)
    Abstract [en]

    In the Swedish electricity system there is a great potential for increasing the cost efficiency of electricity use. Today economic incentives, offered for instance by existing electricity tariffs, are too weak to improve the use of the system. On the Swedish electricity market, there are at least three different participants, the power producer, the distributor and the customer. Today these participants act separately owing to low awareness of the costs for electricity over the year and the day. If the participants are aware of the real electricity costs, cost-effective incentives for cooperation will arise. When participants cooperate, the introduction of end-use measures will reduce system costs for those participants that are involved in cooperation. We present a system analysis for cooperation between distributor and customers. We also present results from a project, where behaviours of an existing distributor and existing customers have been analysed. The results show that there exist cost-effective incentives for cooperation when end-use measures are introduced.

  • 182.
    Andersson, Maria
    et al.
    Linköping University, Department of Mechanical Engineering. Linköping University, Faculty of Science & Engineering.
    Karlsson, Björn
    Linköping University, Department of Mechanical Engineering. Linköping University, Faculty of Science & Engineering.
    Cost-effective incentives for end-use measures in a Swedish municipality1996In: Proceedings of the International Symposium [on] Efficiency, Costs, Optimization, Simulation and Environmental Aspects of Energy Systems: ECOS'96, Stockholm, Sweden, June 25-27, 1996 / [ed] Per Alvfors, Stockholm: KTH Royal Institute of Technology, 1996, p. 557-564Conference paper (Refereed)
    Abstract [en]

    If actors on the electricity market cooperate when end-use measures are introduced the energy-system, cost will be reduced considerably. The marginal cost for electricity for the energy system of the actors will show cost effective incentives for introducing end-use measures. We present a system analysis for cooperation between distributors and customers. We also present results from a project where an existing distributor and eleven existing customers within a municipal energy system have been analysed. The customers are various industries, a hospital, an ice hockey arena, a harbour, a water-works, a warehouse, and a radio tower. The results show that the customers have in different end-use measures a power reduction capacity of maximum 8642 kW. With electricity costs of 1994 this corresponds to a reduction in the energy system cost of 2,852,000 SEK for one year. The results also show that for the distributor`s load curve of 1994, the full power reduction capacity can not be used since the peak loads of the five winter months are not so large and distinct. In that case the energy system cost can be reduced by 1,909,000 SEK, which is 67% of the maximum cost reduction. The end-use measures that are cost effective in this municipal energy system are load management and electricity generation in reserve power plants. We have also studied the profitability for introducing bivalent heating systems based on oil and electricity for heat loads that originally are based on oil. However, with existing electricity and oil costs there are no incentives for increasing the electricity use during non-peak load periods with bivalent heating systems.

  • 183.
    Andersson, Maria
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Ödlund, Louise
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Westling, Hanna
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    The role of the Swedish municipalities in the transition towards sustainable energy systems2019In: WEENTECH Proceedings in Energy, ISSN 2059-2353, Vol. 5, no 1, p. 124-135Article in journal (Refereed)
    Abstract [en]

    Climate change is affecting the planet on a global level and it is of vital importance that actors in the energy system work together to achieve political goals, such as the United Nations' goal which states that the global temperature increase should be kept far below 2 °C. There is a need of actions and collaboration throughout the society. The aim of this paper is to make visible the role of Swedish municipalities in the transition towards sustainable energy systems. The paper presents a study of some ongoing activities and collaborations for increased sustainability where municipalities play a clear role. The study focuses on three areas; (1) municipalities´ activities towards citizens and business community, (2) municipalities’ activities linked to collaboration with other actors, and (3) challenges related to these activities. The study is based on information from a literature search and interviews. Representatives from eight Swedish municipalities have been interviewed. The result shows that the municipalities are involved in various activities and collaborations. This is done via networks, projects, consulting, information dissemination, showing good examples, tryout activities and nudging. Some important challenges have been found. One of them is the transport sector and how to reduce the dependence on fossil fuels. Another is to consider that the Swedish energy system is spread over a large geographical area with different opportunities and limitations concerning electricity production and the sizes of the municipalities. Energy system measures and policy programs need to consider these differences to minimize the risk for sub-optimal energy-system measures. A third challenge is the lack of time and resources within the municipalities to engage enough in energy and climate issues.

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    The role of the Swedish municipalities in the transition towards sustainable energy systems
  • 184.
    Andersson, Martin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Berge, Nils
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Energi- och miljökonsekvenser vid energieffektivisering av belysning och installation av solceller på Nacka Forum i Stockholm2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of energy is increasing worldwide and due to the threat of global warming more and more discussions are made about how the consumption could be reduced and at the same time more sustainable solutions is requested.Buildings consume 40 % of the total global energy where most of it comes from fossil fuels. To reduce the impact of the environment the EU (European Union) has set several goals for that where one is reducing its CO2-emission with 20 % compared to 2008 by the year 2020. One way to do so is from using more efficient technology. This work was made to reduce Nacka Forums electricity bills and that after it had been requested of their owner Unibail-Rodamco. The authors have only looked for solution in areas which the property owners are responsible for like services areas and public spaces. Ideas for reducing their energy use were obtained through studying literature. That study also showed that shopping malls use a lot of energy, especially electricity which mostly is consumed by the building’s lighting. Something that is becoming increasingly more common on buildings is solar cells. Solar cells do not only cut the electricity costs but also decreases the demand on fossil fuels. The shopping mall seemed to have good conditions for such an installation so an investigation was made to see if that could be useful. A plant with a power of 100 kWp was calculated to need 920 m2 roof surface and would yearly produce 93 534 kWh which the authors conclude that it would be a good investment and also highlights that an even bigger plant should be considered. After observing the lights two new solutions were proposed where LED-lamps was considered to be the best source for replacement. Just changing all the light sources would cut the electricity costs a lot but since the existing luminaires was considered to be at the end of their technical lifetime the best solution would therefore be to change both luminaires and light sources. Such solution would decrease the energy use with 544,4 MWh/year and has a payback period of 3,3 years. That energy saving would decrease the CO2-emission with 218 ton/year.This work shows that regardless of which solution that is chosen both of them would decrease the energy use and CO2-emission with 50 %.One of the stores in the shopping mall was using a lot of light which caused problem with the thermal comfort. Despite that, the store does not exceed the limit of 50 W/m2 that is set from the property owner. Such low requirements might hinder any efforts to reduce the energy use and also contribute to unnecessary heat.

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  • 185.
    Andersson, Niklas
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Malmös strategi för social hållbarhet med fokus på förorten2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report covers the social sustainability agenda in the suburbs Rosengård and Kroksbäck, situated in Malmö. These suburbs where constructed mainly in the years 1960-1975 and are now in need of refurbishing. There is also a housing shortage in Malmö and the demand is mainly for inexpensive apartments. Young adults, students, immigrants, senior citizens and families alike are looking for places where they can afford to live. The high demand for living space and the need of renovation could spark a gentrification process which would not be socially sustainable. The main actors whose social sustainability agendas are reviewed are the municipality of Malmö and the municipal owned housing company of MKB as well as the tenants’ association. The report also covers how the dialogue between the residents in Rosengård, the civil servants of the city and the landlords is carried out. Reactions from the residents in Rosengård have been researched in newspapers, but it proved hard to find while criminal reports where abundant. Lastly two examples on how the social sustainability agenda have been carried out in Gothenburg is presented. The methodology which the results are based on is a literature review.

    The report finds that both Malmö and Gothenburg are using a matrix formed decision tool in order to incorporate social aspects in all planning decisions. This is something which works well in both cities. The municipality of Malmö took a decision in 2014 that the social justice will increase when building new apartments. They do however realize the most of the newly constructed homes might be too expensive but they hope that this will eventually free up cheaper apartments. Different investment programs have been initiated in Rosengård, Rosengård I förvandling is one of them. Part of this program was based on local farming and different pedagogical activities. MKB are using social clauses when hiring different contractors, they stipulate that ten percent of the workforce should be locals or people who previously have been unemployed. This would be one the few tangible solutions which MKB is contributing with to solving the problem with lack of social sustainability. The tenants’ association is mainly focusing on minimizing the rent increase. They do however see a potential in so called neighborhood effects such as social learning were tenants are affecting other tenants in a positive way. The tennants’ association believes, as do the municipality of Malmö, that this can be achieved partly by constructing new houses among the older ones.

    The dialogue between the residents and the municipality used to be characterized as too little too late in the planning process. The revised aim with the dialogue is now to bring the citizens opinions into the decision process at an earlier stage. A potential problem could be the language barriers as there are many immigrants living in suburban Malmö. However in projects where the dialogue where given a priority the outcome became a success and the decision enjoys a broad support. As a recommendation for future research, a survey or deep interviews with the residents on their thoughts about actions taken to increase the social sustainability could be carried out. This is something which this report is lacking, good feedback from the residents. 

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  • 186.
    Andersson, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Kärnkraft - Vad är det?2019Other (Other (popular science, discussion, etc.))
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  • 187.
    Andersson, Ronja
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Energimärkning torktumlare: Utredning av energimärkningen på torktumlare samt möjliga förbättringsåtgärder vid körningar med liten last2016Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Different parts of the world use energy in different ways and for different purposes. In Sweden the subsector Laundry and Drying represented 6% of the country’s total electricity use in 2007. In the early 80s it was the big household appliances the dominated the increase of energy use in buildings whereas in recent years have been smaller home electronics and small kitchen appliances that have taken the lead. Due to that the need of energy is constantly increasing a more efficient energy use needs to occur. One step in the right direction was made when the publication of the Brundtland Commission and the term ”Sustainable Development” was born.

     

    In Europe the European Union has a goal that in 2020 the energy use shall be reduced by 20% compared to the forecasted use. To reach the goal they have among other things created the eco-design and the energy labelling directives. These directives are designed to improve the products environmental impact during their whole lifecycle and make it easier for the consumers to compare products from an energy perspective with the help of an energy label. For tumble dryers this energy label has been redesigned to more accurately reflect how much energy that is used when the appliances are running.

     

    In this thesis a comparison of the old and the new energy labelling has been made. Beyond this a consumer survey of how the tumble dryers actually are used in the Swedish households has been performed. Based on this, three suggestions of improvement measures when drying small loads have been investigated regarding to energy use, expenditure of time and final moisture content. A tumble dryer has been used to make the comparison between the two labels. Test runs with full and half loads has been run and the results have been used to calculate the energy efficiency classes for both labels. The three improvement measures were run at half load according to the new label, but with changes to external flow adjustment, internal flow adjustment and tennis ball in the drum separately.

     

    The old energy labelling resulted in energy efficiency class D, right on the border to C, and the new labelling in class C. Although the results seem to be equivalent they differ due to the different scales of the labels. According to the old label the dryer resulted at level 4 but according to the new it resulted at level 6 and is therefore less energy efficient when the runs with half load is taken into account.

     

    The consumer survey showed that the load sizes vary a lot from person to person but with an average load of 4,75 kg dry laundry.

     

    The investigation of the suggestions of improved measures showed a very small difference of the energy use, the expenditure of time was better but the textiles got a higher final moisture content compared to the results from the normal method of drying. These three suggestions of improvement are therefore considered to need further investigation or to be replaced.

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  • 188.
    Andersson Schneider, Katja
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Återvinning av restvärme i en biogasanläggning: Undersökning om värmepump som utnyttjar värme från rötrest i Hagelrums Gård/Biogas anläggning2021Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

    Hagelrums Gård/Biogas is a farm that produces biomethane for transportation from anaerobic digestion. For the anaerobic digestion manure is mainly used in their facility with two digesters.

    This report investigates if installation of a heat pump that takes heat from the digestate would be economically and beneficial for heating of the first digester. The comparison will be done against the facility’s current chip boiler.

    The current facility’s operation and three different scenarios with a heat pump with COP 4 and continuous flow of digestate is presented in the result section. In the results section is also comparisons of how an installation of the proposed heat pump would affect the operation of the facility.

    The conclusion of the project is that a heat pump is not economical or suitable for the current facility. The extra costs and operation of the facility that is not optimal for a heat pump is the reasoning of the conclusion.

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  • 189.
    Andersson, Viktoria
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Elbilar på Lidingö: Påverkan på det regionala elnätet2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis aims towards increasing the understanding of how the growing number of electric cars is going to affect the regional power grid of Stockholm. The results are meant to aid in long term planning of maintenance and development of the regional power grid. Three possible scenarios are presented for the development of electric cars on Lidingo until the year 2040. The number of electric cars, maximum load and load profiles are calculated and analyzed for each scenario. Possible measures of value for the DSO Ellevio are then presented.

    By the year 2040 it is likely that at least one fourth of cars are electric. The maximum power loads from the charging of electric cars will coincide with already existing power peaks during early evening. Loads from charging of electric car will cause a significant contribution to the loads of the regional power grid. If international, national and local climate goals are to be fulfilled the loads would be even larger, though that scenario is deemed unlikely. It is concluded that extensive measures in the regional power grid of Lidingo are needed in order to handle the new maximum loads. It is suggested that Ellevio should start planning for upgrading components, install energy storages and work for load shifting in order to handle the higher loads.

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  • 190.
    Andreasson, Tobias
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Lindh, Emelia
    Halmstad University, School of Business, Engineering and Science.
    Förnybar energi på Svalbard2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree thesis investigates the possibilities of producing food inside a container at Svalbard, using renewable energy and energy storage. The idea was to be able to place the container at remote places without the need of being connected to the grid. We chose Svalbard, where it is cold and the sun is shining 24 hours a day at summertime. In the winter the opposite occurs and the sun is absent from the sky.

    The work is divided into theoretical studies and results based on different calculations. Such as economical evaluations (LCOE), and simulations using the computer programs Matlab and PVsyst. We have investigated if solar power and wind power is suitable as energy sources. Options for storage were batteries, grid and hydrogen storage. Different cases with Photovoltaics- and wind power plants, with batteries or grid, were compared against each other. It is not possible to use the grid as storage. This resulted in different sizing of our cases, with no excess energy production. The result showed that a 5 kWp photvoltaic plant with dual axis tracking system, was the most profitable. The Pay off would be 14 years and the total profit 63 453 SEK. If it will become possible in the future to use the grid at Svalbard as storage, it will open up opportunites for bigger systems. This will lead to higher profit than with smaller ones. Our results show that it is now most profitable with solar power.

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  • 191.
    Andrei, Mariana
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    The role of industrial energy management in the transition toward sustainable energy systems: Exploring practices, knowledge dynamics and policy evaluation2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mitigating climate change represents one of the most pressing challenges of our time. The EU has set the goal of reaching climate neutrality by 2050. The transition of manufacturing organizations is essential in reaching the EU’s goal, since industry accounts for circa 25% of the total final energy use and about one-fifth of EU’s GHG emissions. Energy efficiency stands as one of the essential pillars of industrial decarbonization, with energy management playing a pivotal role in reaching its full potential. To remain competitive in the long term and align with the EU’s carbon neutrality goal for 2050, the manufacturing industry must enhance energy efficiency in a cost-effective way. Manufacturing companies are exploring new ways of working with energy management in order to meet the requirements for both radical and incremental innovations needed to achieve the climate neutrality goal. However, due to the high complexity of industrial energy systems and its high diversity among sectors, improving energy efficiency is a difficult task. Knowledge, especially extensive knowledge, is a key factor for adopting innovations in energy efficiency and industrial processes. 

    The aim of this thesis is to explore the role of industrial energy management in the transition toward sustainable energy systems using an extended system approach. Employing top-down and bottom-up approaches, this thesis specifically focuses on three key aspects: industrial energy management practices, knowledge dynamics in industrial energy management, and policy evaluation. Key aspects of this thesis have been studied by means of mixed methods, such as literature reviews, interviews, case study with action research approach, survey, and evaluations. This thesis advocates that energy management practices (EnMPs) include activities beyond energy efficiency improvements. Specifically, they incorporate activities related to the decarbonization of industrial processes, including energy supply (own and purchased) and fuel conversion, at the very least. 

    The results show that internal EnMPs revolve around a focus on technologies, processes, and leadership, for which knowledge creation is an ongoing and evolving process. EnMPs encompass a comprehensive set of strategies and actions undertaken by manufacturing organizations to enhance energy efficiency, reduce greenhouse gas emissions, and navigate the transition towards sustainable energy systems. Such practices consist of the following components: energy conservation, energy efficiency, process innovation, energy supply and compensation measures. Furthermore, this thesis has shown that external EnMPs are connected to the participation in energy policy programs and voluntary initiatives and is a common practice in energy management work.

    Organizations often employ a combination of these strategies to achieve climate neutrality and align with environmental sustainability goals. Successful implementation of EnMPs is contingent upon deep process knowledge, especially in the case of radical process innovations, which necessitate a thorough understanding of interdependencies and interconnected processes. Collaboration with external sources of knowledge, including universities and stakeholders, is essential to drive innovation and adapt to evolving energy systems. Leadership plays a vital role in navigating these complexities and ensuring a strategic approach to EnMPs implementation. 

    This thesis contributes to the field of research on energy management in different ways: i. re-viewing the role of energy management in the current context of transition toward sustainable energy systems, ii. advancing theoretical and practical understanding of energy management in manufacturing organizations, iii. enhancing the knowledge-creation perspective within energy management practices for enhancing the adoption of both energy efficiency and process innovation, and iv. advancing theoretical understanding of the knowledge-creation process for energy management through the development of a knowledge-based framework. 

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  • 192.
    Andrei, Mariana
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Rohdin, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Wallin, Johanna
    Volvo Construction Equipment Operations Hallsberg, 694 32, Hallsberg, Sweden.
    Tångring, Magnus
    Volvo Construction Equipment Operations Hallsberg, 694 32, Hallsberg, Sweden.
    Exploring a decarbonization framework for a Swedish automotive paint shop2024In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 200, article id 114606Article in journal (Refereed)
    Abstract [en]

    The automotive industry is the world’s largest manufacturing activity, characterized by complex productionprocesses and some energy-intense processes which use a significant quantity of raw materials. The production processes responsible for the highest energy end-use take place in the paint shop. Depending on the type of paintshop processes, the energy use can account for up to 75 % of the plant’s total energy end-use. This study aims to contribute to an enhanced understanding of the complexity of adopting decarbonization measures and to provide support for planning and decision-making in practice. By adopting a bottom-up perspective, a longitudinal case study was conducted on a state-of-the-art automotive paint-shop between November 2019 and March 2023. To achieve the study’s aim, a bottom-up methodology was developed comprising several steps: i) analysis of decarbonization measures, ii) mapping of process energy use and CO2 emissions, and iii) economic analysis. The data-based methodology is flexible and can be applied in different automotive paint-shops. Main findings show that i) incremental energy efficiency measures have the fastest adoption level, with relatively high savings potential,and most of these are cost effective; ii) radical process innovation measures have a higher savings potential, but long-term adoption levels due to the radical innovations required in the supply chain, and the highly specialized knowledge needed in the pre-treatment process; and iii) the primary drivers for implementing the measures are to achieve the climate targets and establish a leading position in the sector, rather than focusing primarily on the cost-effectiveness of the measures.

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    Exploring a decarbonization framework for a Swedish automotive paint shop
  • 193.
    Andrei, Mariana
    et al.
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Reducing the Energy Efficiency Gap by Means of Energy Management Practices2019In: 2019 ACEEE Summer Study on Energy Efficiency in Industry, Portland, August 12-14, 2019: Inspiring Action for a Sustainable Future. Panel 2: People, 2019Conference paper (Refereed)
    Abstract [en]

    Energy efficiency remains a cornerstone in climate change mitigation. Research onimproved energy efficiency has shown the existence of a gap between the optimal and currentimplementation of energy efficient technologies, which is referred to as the energy efficiencygap. Studies have identified that energy efficiency could be further improved by includingenergy management practices alongside energy-efficient technologies. The inefficiencies ofenergy efficiency are commonly explained by the existence of various barriers to energyefficiency. Energy management is stated to be one of the foremost means of overcoming thesebarriers, and two important factors that can help are energy services and energy data monitoring.The aim of this paper is to address how energy services and energy data monitoring can helpeliminate the energy efficiency gap. The study has been carried out as a multiple case studyusing semi-structured interviews.Two aspects of energy management are included: Energy Performance Contract (EPC)and the concept of “Smart” processes and subprocesses. EPC is a commercial model that ispreferably to be designed in a way that it can remove barriers and allow driving forces to beeffective within the contract, and the concept of smart processes and subprocesses, that implies abetter use of big data from measurements and intra-machine connectivity by using the Internet ofThings. Major barriers to energy efficiency are high transaction costs, problems with financingand competition with in-house expertise. Thus, by introducing the EPC and “Smart” concept, areduction of the energy efficiency gap could be achieved.

  • 194.
    Andrei, Mariana
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Pierre, Inge
    Energiforetagen Sverige, Sweden.
    Gindroz, Bernard
    CEN CENELEC Sect Forum Energy Management SFEM, Belgium.
    Rohdin, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Decarbonization of industry: Guidelines towards a harmonized energy efficiency policy program impact evaluation methodology2021In: Energy Reports, E-ISSN 2352-4847, Vol. 7, p. 1385-1395Article in journal (Refereed)
    Abstract [en]

    The decarbonization of EU energy system is under way, but manufacturing industry is still using approximately 25% of the EU total final energy use. To maintain long-term competitiveness while contributing to the EU goal of carbon neutrality by 2050, manufacturing industry needs to improve energy efficiency in a cost-effective way. One important way to achieve this is through energy audits. The Energy Efficiency Directive promotes member states development of energy efficiency programs to encourage industry to undergo energy audits. Previous studies have reviewed industrial energy efficiency policy program evaluations and argued that there is no harmonized way to conduct them. This leads to difficulties in: i) comparing energy efficiency and cost saving potentials throughout different programs, and ii) providing necessary information that supports the improvement of the policy program. Therefore, we argue that a harmonized methodology for industrial energy efficiency policy program evaluation is of great importance, and, we have developed a set of five-steps guidelines that lay the foundation for an ex-ante energy efficiency policy program evaluation methodology. The guidelines are to be be conducted during the lifetime of the program, in five steps, as follows: (s1) define key issues, (s2) set the objectives for each key issue, (s3) identify the options for each key issue, (s4) analyze options from an energy and environmental perspective, and (s5) compare options and select the recommended one. Our proposed methodology will support policymakers and evaluators answer questions such as: i) how can the objectives of the policy program be achieved? ii) is there any need to change the policy program? Furthermore, a comparison in terms of relevance, efficiency, effectiveness, and sustainability of all major policy options developed, including the status quo option is proposed in the methodology. This paper can be seen an important step towards the goal of creating a harmonized policy evaluation methodology. (C) 2021 The Authors. Published by Elsevier Ltd.

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  • 195.
    Andrei, Mariana
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Rohdin, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Bertoldi, Paolo
    European Commission, Joint Research Center, Via Enrico Fermi 2749, Ispra 21027, Italy.
    Mac Nulty, Hannes
    Green Industry Platform, Growth Knowledge Partnership, Geneva CH-1219, Switzerland.
    Exploring the design of voluntary initiatives from the transition management perspective – A means for industrial decarbonization2024In: Energy Reports, ISSN 2352-4847, Vol. 11, p. 5894-5909Article in journal (Refereed)
    Abstract [en]

    Recent studies claim that national policies fall short of the ambitious goal to limit global temperature increase to well below 2°C, preferably 1.5°C, revealing an ambition gap between current commitments and those needed to reach climate neutrality. To bridge this gap, commitments must increase more than fivefold to achieve the necessary reduction in GHG emissions. Voluntary initiatives (VIs), gaining interest as an approach to support the Paris Agreement's ambition, have the potential to bridge the commitment gap and limit the expected temperature increase to 2°C if all their voluntary commitments to climate neutrality are fulfilled. While decarbonizing the manufacturing sector is crucial for climate targets, no prior study has explored the theoretical potential of industry-related VIs to bridge the gap for industrial decarbonization. This paper addresses this gap by examining the potential contribution of these VIs, analyzing criteria related to arena and agenda creation, operationalization, and accountability. By applying the transition management framework innovatively, the study investigates eighty-three industry-related VIs led by both state and non-state actors. The research process, involving the development of an analytical framework, VIs selection, data collection and validation, categorization, and analysis, provides insights into how the design affects VIs' potential for industrial decarbonization. The main findings highlight, firstly, the need for clearly defined and measurable targets, enhanced commitments, and robust accountability mechanisms, especially for non-state actor-led initiatives. Secondly, increased participation from energy-intensive sector companies due to their pivotal role for GHG emission reduction. Lastly, collaboration between state and non-state actors is critical for bridging the decarbonization gap in manufacturing industries. Additionally, the similarity between VIs and voluntary agreement programs (VAPs) is highlighted, with VAPs been overseen by governmental bodies with administrative authority. Given the urgency of addressing climate change, an unanswered question remains: Will future policies transition away from voluntariness towards more mandatory administrative character?

  • 196.
    Andricciola, Antonio
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Development of an algorithm for the automatic adjustment of the heating curve of a heat pump heating system2018Independent thesis Advanced level (degree of Master (Two Years)), 5 HE creditsStudent thesis
    Abstract [en]

    This work deals with the problem of choosing the correct heating curve for a certain building package (envelope plus distribution system). This topic is particularly relevant in countries like Sweden where heating curve is the most common way to control heat pumps. The analysis, involving four building models with respective distribution systems (two have floor heating and two radiators) and a variable speed GSHP, shows how, for a fixed location, the proper heating curve changes considering different building envelopes and different emitters. It is highlighted, therefore, how the adoption of a generic heating curve for all the buildings can cause discomfort and energy inefficiency. An algorithm to adjust the curve is then presented, and the results are compared with the reference case. The algorithm manages to improve comfort considerably and, for the A-class building, also SPF increases a lot (12.5%). The whole study was performed by means of TRNSYS® neglecting the DHW demand.

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  • 197. Andrén, Lars
    et al.
    Persson, Tomas
    Högskolan Dalarna, Energi och miljöteknik.
    Lennermo, Gunnar
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Handbok för kombinerade sol- och biovärmesystem: Teknik - System - Ekonomi2012Report (Other academic)
    Abstract [sv]

    Handboken beskriver olika solfångarkonstruktioner och solvärmekretsens ingående komponenter och ger en grundlig inblick i ackumulatortankens konstruktion och funktion. I boken finns förslag på systemutformning, olika tekniska lösningar och hur systemen bör styras och regleras. Handboken beskriver i första hand utformning-lösning-styrning av kombinationen sol- och pelletsvärme, men tar även upp solvärme i kombination med vedpannor, värmedrivna vitvaror och värmepumpar. Värmesystem med vattenburen värme är utmärkta att kombinera med solvärme, men det är i de flesta fall enklare att få till bra lösningar vid nyinstallation, än vid komplettering av befintlig anläggning. När solvärme och pelletsvärme ska kombineras finns det många alternativ till systemutformning. Det är viktigt att vattenburna pelletssystem utformas korrekt och kombineras på rätt sätt med solvärme för att komforten ska bli hög och elanvändningen låg. Vattenmantlade pelletskaminer med ett vattenburet värmesystem är extra intressant i kombination med solvärme. När eldningen upphör i samband med att värmebehovet avtar kan solvärmen ta över. En generell slutsats är att konventionella svenska pelletspannor med inbyggd varmvattenberedning inte är lämpliga i kombination med solvärmesystem. Den typen av bränslepannor ger komplicerade systemlösningar, höga värmeförluster och det är svårt att åstadkomma en tillräckligt bra temperaturskiktning i ackumulatortanken om varmvattenberedning sker i pannan. Solvärme för varmvattenberedning kan vara ett enkelt och bra komplement till pelletskaminer som genererar varmluft. För solvärmesystem är det viktigt att kraftig temperaturskiktning erhålls när värmelagret laddas ur. Det betyder att ackumulatortankens (eller varmvattenberedarens) nedre vattenvolym ska kylas ner till temperaturer som ligger nära ingående kallvattentemperatur. Ackumulatortankens mellersta del bör kylas till samma temperatur som radiatorreturen. Vid design av solfångarkretsen måste överhettning och stagnation kunna klaras utan risk för glykolnedbrytning eller andra skador på värmebärare eller rörkrets (och andra komponenter i kretsen). Partiell förångning minskar risken för att glykolen skadas då solfångaren når höga stagnationstemperaturer. Solfångarens glykolblandning tillåts koka (förångas) på ett kontrollerat sätt så att endast ånga blir kvar i solfångaren. Vätskevolymen i solfångaren samlas upp i ett större expansionskärl och systemet återfylls när vätskan kondenserar. Dränerande solfångarsystem med enbart vatten är ett möjligt alternativ till konventionella solfångare. De kräver en större noggrannhet vid installationen, så att sönderfrysning undviks. Dränerande systemlösningar är relativt ovanliga i Sverige. Om solfångaren under senhöst-vinter-tidig vår kan arbeta med att förvärma kallvatten från 10 till 20 ºC erhålls en betydligt bättre verkningsgrad på solfångaren (och framför allt ökar värmeutbytet då drifttimmarna ökar väsentligt) än om radiatorreturen (som i bästa fall ligger på temperaturnivån 30 - 40 ºC) ska förvärmas. Därför bör radiatorreturen placeras en bra bit upp från botten i ackumulatortanken och tappvarmvattnet ska förvärmas i en slinga som börjar i tankens botten. Om det finns ett VVC-system måste systemet anslutas på ett speciellt sätt så att ackumulatortankens temperaturskiktning inte störs. En viktig parameter vid ackumulatortankens utformning är att värmeförlusterna hålls låga. Det är viktigt för att klara tappvarmvattenlasten med solvärme under mulna perioder sommartid (men också för att hålla energianvändningen låg). I moderna hus, där ackumulatortanken i regel placeras i bostaden, blir det en komfortfråga att undvika övertemperaturer i det rum där värmelagret placeras. En bra standard på isoleringen (med minimerade värmeförluster) kräver att det finns ett lufttätt skikt över hela isoleringen som dessutom sluter tätt mot röranslutningar. Ofrivillig självcirkulation i anslutande kretsar som kan kyla av och blanda om ackumulatortankens vattenvolym, bör förhindras med backventiler och nedböjning av rören i isolerskiktet eller direkt utanför tanken.

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  • 198. Andrén, Lars
    et al.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Lennermo, Gunnar
    Handbok för kombinerade sol- och biovärmesystem: Teknik - System - Ekonomi2012Report (Other academic)
    Abstract [sv]

    Handboken beskriver olika solfångarkonstruktioner och solvärmekretsens ingående komponenter och ger en grundlig inblick i ackumulatortankens konstruktion och funktion. I boken finns förslag på systemutformning, olika tekniska lösningar och hur systemen bör styras och regleras. Handboken beskriver i första hand utformning-lösning-styrning av kombinationen sol- och pelletsvärme, men tar även upp solvärme i kombination med vedpannor, värmedrivna vitvaror och värmepumpar. Värmesystem med vattenburen värme är utmärkta att kombinera med solvärme, men det är i de flesta fall enklare att få till bra lösningar vid nyinstallation, än vid komplettering av befintlig anläggning. När solvärme och pelletsvärme ska kombineras finns det många alternativ till systemutformning. Det är viktigt att vattenburna pelletssystem utformas korrekt och kombineras på rätt sätt med solvärme för att komforten ska bli hög och elanvändningen låg. Vattenmantlade pelletskaminer med ett vattenburet värmesystem är extra intressant i kombination med solvärme. När eldningen upphör i samband med att värmebehovet avtar kan solvärmen ta över. En generell slutsats är att konventionella svenska pelletspannor med inbyggd varmvattenberedning inte är lämpliga i kombination med solvärmesystem. Den typen av bränslepannor ger komplicerade systemlösningar, höga värmeförluster och det är svårt att åstadkomma en tillräckligt bra temperaturskiktning i ackumulatortanken om varmvattenberedning sker i pannan. Solvärme för varmvattenberedning kan vara ett enkelt och bra komplement till pelletskaminer som genererar varmluft. För solvärmesystem är det viktigt att kraftig temperaturskiktning erhålls när värmelagret laddas ur. Det betyder att ackumulatortankens (eller varmvattenberedarens) nedre vattenvolym ska kylas ner till temperaturer som ligger nära ingående kallvattentemperatur. Ackumulatortankens mellersta del bör kylas till samma temperatur som radiatorreturen. Vid design av solfångarkretsen måste överhettning och stagnation kunna klaras utan risk för glykolnedbrytning eller andra skador på värmebärare eller rörkrets (och andra komponenter i kretsen). Partiell förångning minskar risken för att glykolen skadas då solfångaren når höga stagnationstemperaturer. Solfångarens glykolblandning tillåts koka (förångas) på ett kontrollerat sätt så att endast ånga blir kvar i solfångaren. Vätskevolymen i solfångaren samlas upp i ett större expansionskärl och systemet återfylls när vätskan kondenserar. Dränerande solfångarsystem med enbart vatten är ett möjligt alternativ till konventionella solfångare. De kräver en större noggrannhet vid installationen, så att sönderfrysning undviks. Dränerande systemlösningar är relativt ovanliga i Sverige. Om solfångaren under senhöst-vinter-tidig vår kan arbeta med att förvärma kallvatten från 10 till 20 ºC erhålls en betydligt bättre verkningsgrad på solfångaren (och framför allt ökar värmeutbytet då drifttimmarna ökar väsentligt) än om radiatorreturen (som i bästa fall ligger på temperaturnivån 30 - 40 ºC) ska förvärmas. Därför bör radiatorreturen placeras en bra bit upp från botten i ackumulatortanken och tappvarmvattnet ska förvärmas i en slinga som börjar i tankens botten. Om det finns ett VVC-system måste systemet anslutas på ett speciellt sätt så att ackumulatortankens temperaturskiktning inte störs. En viktig parameter vid ackumulatortankens utformning är att värmeförlusterna hålls låga. Det är viktigt för att klara tappvarmvattenlasten med solvärme under mulna perioder sommartid (men också för att hålla energianvändningen låg). I moderna hus, där ackumulatortanken i regel placeras i bostaden, blir det en komfortfråga att undvika övertemperaturer i det rum där värmelagret placeras. En bra standard på isoleringen (med minimerade värmeförluster) kräver att det finns ett lufttätt skikt över hela isoleringen som dessutom sluter tätt mot röranslutningar. Ofrivillig självcirkulation i anslutande kretsar som kan kyla av och blanda om ackumulatortankens vattenvolym, bör förhindras med backventiler och nedböjning av rören i isolerskiktet eller direkt utanför tanken.

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    fulltext
  • 199. Angioni, A.
    et al.
    Lu, Shengye
    Hooshyar, Hossein
    KTH, School of Electrical Engineering (EES), Electric Power and Energy Systems.
    Cairo, Ignasi
    Repo, Sami
    Ponci, Ferdinanda
    Della Giustina, Davide
    Kulmala, Anna
    Dede, Alessio
    Monti, Antonello
    Del Rosario, Gerard
    Vanfretti, Luigi
    KTH, School of Electrical Engineering (EES), Electric Power and Energy Systems.
    Garcia, C.C.
    A distributed automation architecture for distribution networks, from design to implementation2018In: Sustainable Energy, Grids and Networks, E-ISSN 2352-4677, Vol. 15, p. 3-13Article in journal (Refereed)
    Abstract [en]

    With the current increase of distributed generation in distribution networks, line congestions and PQ issues are expected to increase. The smart grid may effectively coordinate DER, only when supported by a comprehensive architecture for automation. In IDE4L project such architecture is designed based on monitoring, control and business use cases. The IDE4L instance of SGAM architecture is derived and explained in details. The automation actor are specified in terms of interfaces, database and functions. The division in these three layers boosted the implementation phase as dedicated interfaces, databases or application has been developed in a modular way and can be installed in different HW/SW. Some implementation instances are presented and the main output of the architecture is discussed with regards to some indexes as communication traffic and level of distribution of automation functions.

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    fulltext
  • 200.
    Anglart, Henryk
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Engineering.
    Li, Haipeng
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Engineering.
    Niewinski, Grzegorz
    Warsaw Univ Technol, Inst Heat Engn, Nowowiejska 21-25, PL-00665 Warsaw, Poland..
    Mechanistic modelling of dryout and post-dryout heat transfer2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 161, p. 352-360Article in journal (Refereed)
    Abstract [en]

    In this paper a new mechanistic model for the diabatic annular two-phase flow is presented and applied to prediction of dryout and post-dryout heat transfer in various channels. The model employs a computational fluid dynamics code - OpenFOAM (R) - to solve the governing equations of two-phase mixture flowing in a heated channel. Additional closure laws have been implemented to calculate the location of the dryout and to predict wall temperature in the post-dryout region. Calculated results have been compared with experimental data obtained in pipes and good agreement between predictions and measurements has been achieved. The presented model is applicable to complex geometries and thus can be used for prediction of post-dryout heat transfer in a wide variety of energy conversion systems.

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