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  • 151.
    Almulla, Youssef
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Gulf Cooperation Council (GCC) countries 2040 energy scenario for electricity generation and water desalination.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Judicious modeling of an energy system can help provide insights as to how elements of the energy system might be configured in the longer term. The current and future electricity and water desalination systems of each GCC country were represented using a full-cost based optimization tool called MESSAGE and the following scenarios were examined:

    1. The business as usual scenario (BAU): current energy system is extended into the future without any changes. The energy system structure and characteristics are kept the same. The fuel prices are also kept at the current subsidized levels.

    2 - The netback-pricing scenario: all fuel costs are increased to the international market price. The freed amount of fuel is assumed to be available for export to the international market. Moreover, this scenario examines different carbon tax options of 0, 20,30 ,40 and 50 dollars per kilo tons of CO2 emissions.

    3 - The Nuclear hub scenario: examines the idea of a “nuclear hub” state for the GCC region that can have all the “know-how” and logistics to provide sufficient nuclear energy for the GCC through the Interconnection Grid “GCCIG”.

    Results shows that fossil fuels will continue to play an important role in a least cost future for the region. This is due, in no small part, to the cheap natural gas resources in the GCC. Despite the high renewable energy technologies potential, their penetration – given the study assumptions - proved to be important, but limited in the GCC. On the other hand, nuclear energy shows clear economic potential. 

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  • 152.
    Almulla, Youssef
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Ramirez Gomez, Camilo
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Joyce, Brian
    Stockholm Environm Inst, SEI US, Boston, MA USA..
    Huber-Lee, Annette
    Stockholm Environm Inst, SEI US, Boston, MA USA..
    Nerini, Francesco Fuso
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    From participatory process to robust decision-making: An Agriculture-water-energy nexus analysis for the Souss-Massa basin in Morocco2022In: Energy for Sustainable Development, ISSN 0973-0826, E-ISSN 2352-4669, Vol. 70, p. 314-338Article in journal (Refereed)
    Abstract [en]

    The Water-Energy-Food (WEF) framework is widely used to address sustainability and resource management questions. However, many WEF methods miss engaging with stakeholders in the process. In this study, we intro-duce a stakeholder-driven and model-supported robust nexus decision-making framework. This methodology is exemplified by a case study in the Souss-Massa basin (SMB) which has significant importance for the agricultural sector in Morocco. However, the water scarcity exacerbated by climate change, overexploitation of groundwater and heavy use of fossil fuels for pumping is threatening the future of this fertile land. An integrated agriculture, water and energy model was developed to explore various potential solutions or scenarios such as desalination, wastewater reuse and improved water productivity. The analysis revealed that engaging with stakeholders and developing common robust nexus decision metrics is essential to establishing a shared and transparent approach to address the complicated nexus challenges. It also showed that no one solution can address all nexus challenges and highlighted the need for an integrated strategy that stimulates the contributions from different sectors. Fi-nally, the transition from fossil fuel groundwater pumping to solar pumping is shown to be economically and en-vironmentally viable.

  • 153.
    Almulla, Youssef
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Ramirez Gomez, Camilo
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electric Power and Energy Systems.
    Pegios, Konstantinos
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Korkovelos, Alexandros
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis. World Bank, 1818 H St NW, Washington, DC 20433 USA..
    Strasser, Lucia de
    United Nations Econ Commiss Europe UNECE, Bur S411, CH-1211 Geneva 10, Switzerland..
    Lipponen, Annukka
    United Nations Econ Commiss Europe UNECE, Bur S411, CH-1211 Geneva 10, Switzerland..
    Howells, Mark
    Loughborough Univ, Sch Social Sci & Humanities, Dept Geog, Epinal Way, Loughborough LE11 3TU, Leics, England.;Imperial Coll London, Fac Nat Sci, Ctr Environm Policy, 16-18 Princes Gardens, London SW7 1NE, England..
    A GIS-Based Approach to Inform Agriculture-Water-Energy Nexus Planning in the North Western Sahara Aquifer System (NWSAS)2020In: Sustainability, E-ISSN 2071-1050, Vol. 12, no 17, article id 7043Article in journal (Refereed)
    Abstract [en]

    The North Western Sahara Aquifer System (NWSAS) is a vital groundwater source in a notably water-scarce region. However, impetuous agricultural expansion and poor resource management (e.g., over-irrigation, inefficient techniques) over the past decades have raised a number of challenges. In this exploratory study, we introduce an open access GIS-based model to help answer selected timely questions related to the agriculture, water and energy nexus in the region. First, the model uses spatial and tabular data to identify the location and extent of irrigated cropland. Then, it employs spatially explicit climatic datasets and mathematical formulation to estimate water and electricity requirements for groundwater irrigation in all identified locations. Finally, it evaluates selected supply options to meet the electricity demand and suggests the least-cost configuration in each location. Results indicate that full irrigation in the basin requires similar to 3.25 billion million m(3)per year. This translates to similar to 730 GWh of electricity. Fossil fuels do provide the least-cost electricity supply option due to lower capital and subsidized operating costs. Hence, to improve the competitiveness of renewable technologies (RT) (i.e., solar), a support scheme to drop the capital cost of RTs is critically needed. Finally, moving towards drip irrigation can lead to similar to 47% of water abstraction savings in the NWSAS area.

  • 154.
    Almulla, Youssef
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Ramos, Eunice
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Gardumi, Francesco
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Taliotis, Constantinos
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Lipponen, A.
    Howells, Mark I.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    The role of energy-water nexus to motivate transboundary cooperation: An indicative analysis of the Drina river basin2018In: International Journal of Sustainable Energy Planning and Management, E-ISSN 2246-2929, Vol. 18, p. 3-28Article in journal (Refereed)
    Abstract [en]

    Low-carbon hydropower is a key energy source for achieving Sustainable Development Goal 7-sustainable energy for all. Meanwhile, the effects of hydropower development and its operation are complex-and potentially a source of tension on Transboundary Rivers. This paper explores solutions that consider both energy and water to motivate transboundary cooperation in the operation of hydropower plants (HPPs) in the Drina River Basin (DRB) in South-East Europe. Here the level of cooperation among the riparian countries is low. The Open Source energy Modeling System-OSeMOSYS was used to develop a multi-country model with a simplified hydrological system to represent the cascade of HPPs in the DRB; together with other electricity options, including among others: energy efficiency. Results show that improved cooperation can increase electricity generation in the HPPs downstream without compromising generation upstream. It also demonstrates the role of inexpensive hydropower to enhance electricity trade in the region. Implementing energy efficiency measures would reduce the generation from coal power plants, thereby mitigating CO 2 emissions by as much as 21% in 2030 compared to the 2015 levels. In summary, judicious HPP operation and electricity system development will help the Western Balkans reap significant gains.

  • 155.
    Almulla, Youssef
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Zaimi, Klodian
    Polytechnic University of Tirana (UPT).
    Fejzic, Emir
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Sridharan, Vignesh
    Imperial College London.
    De Strasser, Lucia
    UNECE.
    Gardumi, Francesco
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Hydropower and Climate Change, insights from the Integrated Water-Energy modelling of the Drin Basin.Manuscript (preprint) (Other academic)
    Abstract [en]

    The understanding of the transboundary impact of Climate Change on hydropower is not well-established in the literature, where few studies take a system perspective to understand the relative roles of different technological solutions for coordinated water and energy management. This study contributes to addressing this gap by introducing an open-source, long-term, technologically-detailed water and energy resources cost-minimisation model for the Drin River Basin, built in OSeMOSYS. 

    The analysis shows that climate change results in a 15-52% annual decline in hydro generation from the basin by mid-century. Albania needs to triple its investments in solar and wind to mitigate the risk of climate change. Changing the operational rules of hydropower plants has a minor impact on the electricity supply. However, it can spare significant storage volume for flood control. 

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  • 156.
    Almulla, Youssef
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Zaimi, Klodian
    Polytech Univ Tirana UPT, Blvd Deshmoret & Kombit 4, Tirana, Albania..
    Fejzic, Emir
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Sridharan, Vignesh
    Imperial Coll London, Chem Engn Dept, London SW7 2AZ, England..
    de Strasser, Lucia
    United Nations Econ Commiss Europe UNECE, Bur S411, CH-1211 Geneva 10, Switzerland..
    Gardumi, Francesco
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Hydropower and climate change, insights from the integrated water-energy modelling of the Drin Basin2023In: Energy Strategy Reviews, ISSN 2211-467X, E-ISSN 2211-4688, Vol. 48, article id 101098Article in journal (Refereed)
    Abstract [en]

    The understanding of the transboundary impact of Climate Change on hydropower is not well-established in the literature, where few studies take a system perspective to understand the relative roles of different technological solutions for coordinated water and energy management. This study contributes to addressing this gap by introducing an open-source, long-term, technologically-detailed water and energy resources cost-minimisation model for the Drin River Basin, built in OSeMOSYS.The analysis shows that climate change results in a 15-52% annual decline in hydro generation from the basin by mid-century. Albania needs to triple its investments in solar and wind to mitigate the risk of climate change. Changing the operational rules of hydropower plants has a minor impact on the electricity supply. However, it can spare significant storage volume for flood control.

  • 157.
    Almén, Ylva
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Cooling in the ALICE detector2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At CERN, the European Laboratory for Particle Physics in Geneva, Switzerland, a new modern particle accelerator called the LHC, Large Hadron Collider, is being projected. One of the four large detectors of the LHC, ALICE, consists of many sub-detectors. Temperature stability in ALICE is of great importance for the experiments performed here. 

    In the ALICE sub-detector TPC, Time Projection Chamber, there is a great risk for thermal instability.  This will cause false data in the experiments, and therefore it is imperative to come to terms with the problem. One suggested solution is to install a water-cooled thermal screen around the TPC detector. The task of this thesis work was to design the new thermal screen and to evaluate its thermal abilities by computer simulations. Then, this chosen screen was to be simulated together with the TPC and its drift gas and the results studied. It was also desirable to see what would happen in case of parts of the thermal screen malfunctioning. 

    Several different designs of the thermal screen have been made and analysed, and the most efficient model has been selected. The chosen model succeeded in keeping a fairly homogenous temperature level and also had good cooling abilities. All simulations were made using the computer software STAR-CD. The next phase of the project involved modelling the thermal screen around the TPC field cage containing drift gas of a certain temperature. 

    The results of the simulations show that the performance of the cooling thermal screen is unsatisfactory. Although the screen itself seems to work efficiently, it does not succeed in keeping the TPC at an acceptable temperature level. The screen temperature rises more than the desired maximum of 0.5K. The scenario with parts of the thermal screen malfunctioning resulted in temperature peaks of +2K, which is unacceptable.

     The conclusions drawn are therefore that the thermal screen must be allowed to be thicker or a new solution must be found. The idea of a thermal screen is a good one, but the limitations in the design of the thermal screen must be redefined if the cooling problem is to be solved.

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  • 158.
    Alros, Malin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Energikartläggning av VVC-systemet i flerbostadshus2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I studien har värmeförlusterna i VVC-systemet för flerbostadshus studerats. Bakgrunden byggde på att många montörer upplevde att teknisk isolering blir bortprioriterat i byggprojekten. Som argument till att inte prioritera den tekniska isoleringen använd uttrycket ”värmen kommer fastigheten tillgodo”, där de menar att värmeförlusterna i varmvattenrören utnyttjas av fastigheten på annat sätt. Syftet med detta examensarbete har varit att undersöka hur den tekniska isoleringen påverkar varmvattenförlusterna samt att kartlägga vart värmeförlusterna sker och om värmeförlusterna kommer huset tillgodo. För att uppnå målen har egna mätningar i två flerbostadshus gjorts samt mätdata erhållits från ytterligare två fastigheter. De egna mätningarna pågick under två veckor där framledning- och returledningstemperatur i varmvattencirkulationen mättes. Den ena fastigheten hade äldre isolering medan den andre hade genomgått renovering där samtliga rörledningar bytts ut och där modern isolering används. Förutsättningarna för de olika fastigheterna studerades så som rörtjocklek, isoleringstyp, isoleringstjocklek samt omgivningstemperatur. För de andra två fastigheterna erhölls framledning- och returledningstemperatur i varmvattencirkulationen under åren 2012 och 2013.

    Studien visade att förlusterna i VVC-systemet inte påverkas av årstiden utan var konstanta över året. Fastigheterna med äldre isolering hade stora värmeförluster i förhållande till distributionsrörens längd. Även i fastigheten med modern isolering upptäcktes stora brister i monteringen av isoleringen varvid värmeförlusterna blev större än förväntat. Båda fastigheterna som mättes hade en returtemperatur som var under den rekommenderar temperatur enligt BBR, som är. 55°C vilket medför en hälsorisk på grund av ex tillväxt av legionella i rörsystemet. Värmeförlusterna visade sig vara stora i källarkorridorer och där värmen la sig längst med taket och gav ett dåligt uppvärmningstillskott till källarkorridoren. De vertikala rörschakten var igenmurade vilket gjorde det svårt att undersöka värmeförlusterna. Det kunde även observeras hur varmvattenrören värmer upp kallvattenröret. Vilket medför en ökar resursanvändning av vattnet då användaren måste spola kranen längre för att erhålla kallt kallvatten eller varmt varmvatten.

    Slutsatsen av studien är att värmeförlusterna från varmvattencirkulationen inte utnyttjas av byggnaden på ett bra sätt. Värmeförlusterna är okontrollerade vilket ökar risken för överhettning för vissa utrymmen. Dessutom kan rörschakt och källare hållas lägre än boendetemperaturen och under sommarmånaderna finns dessutom inget uppvärmningsbehov. Det finns stor potential att investera i tjockare rörisolering vid stambyte och vid nybyggnation. Bara skillnaden mellan de fastigheter som undersöktes i denna studie visar att förlusterna varierar mellan 450 och 1960 kWh per lägenhet och år. Skulle Fastighet 1 renovera sitt VVC-system kan en besparing på 33 800 SEK göras och en återbetalning sker inom ett halvår. Studien bekräftade att ett välisolerat VVC-system kommer resultera i bättre komfort för användaren, lägre värmeförluster och lägre kostnader för systemet. 

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  • 159.
    Alros, Malin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Hagberg, Anna-Klara
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Utsikten: Hållbara uppvärmningsalternativ för vandrarhemmet på Finnhamn2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Finnhamn is a small group of islands in the Stockholm archipelago. At Stora Jolpan, the biggest island, there is a hostel. The main building was built in 1915 and is called Utsikten. The purpose of this project is to on behalf of the Archipelago Foundation (Skärgårdsstiftelsen) find alternative systems that can replace the existing heating system of Utsikten (an oil-fired boiler and electricity heaters) to a system with renewable energy. The alternative system that this project focuses on is a system of solar collectors combined with a wood chip boiler. Information for the project is collected from a literature review. Also persons with good knowledge of renewable energy systems, or Finnhamn and the hostel, have been contacted.The present need for tap water related energy at Utsikten is calculated in two different ways using estimated data about the guests’ behaviors. The energy required to heat the building is calculated using general values for the amount of energy needed to heat a square meter. Dimensioning and cost calculations for the new system are made by companies supplying the current systems and subsystems. Calculations of the economic aspects as well amounts of carbon dioxide emissions are also made.Finally it is found that the suggested heating systems could be applicable on Utsikten. However, the system has difficulties which have to be dealt with. The total heat related need of energy during a year is calculated to 93 000-138 000 kilowatt hours. The solar collectors are suggested to use 41-96 square meters of the roof, complemented with 81-156 cubic meters wood chips.

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    Utsikten: Hållbara uppvärmningsalternativ för vandrarhemmet på Finnhamn
  • 160.
    AlShaaibi, Sultan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis. Tecnalia.
    Transition towards Low-Carbon Energy System for the Basque Country, Study of Scenarios for 2050 Master2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    TECNALIA Research & Innovation is the first privately funded applied research centre in Spain and one of the leading such centres in Europe. A renowned technological agent in the development of innovative and sustainable solutions for the energy and environmental challenges of industry and society, TECNALIA addresses the complex challenges of energy supply chain and energy systems.

    Contributing to these efforts, the project builds a model of the energy system in Basque Country, which is characterized by (1) high representation of industry; the most energy intensive sector (about 45% in the energy demand ) (2) the high consumption of fossil fuels (about 83% of Basque energy use in 2010).

    These challenges (and others) along with the compliance with EU targets to reduce GHGs emissions, to promote renewables and implement measures for energy savings and efficient use of energy, are key drivers to simulate different policy-based scenarios to study and analyze the impact of these measures over different time frames.

    The aim of this thesis is prepare energy scenarios for the Basque Country for 2050, taking into account different low-carbon pathways and integrating a life-cycle perspective which includes not only the impact during the use and operation phase of energy systems, but also the impacts during the other life cycle phases (manufacturing, installation, end of life).

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  • 161.
    Alumbreros Rodríguez, Miguel
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Decarbonisation pathways for the Indonesian power system: policy measures and financial schemes options2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In view of the potential threat climate change poses around the globe, countries are pledging to emission reductions to alleviate its consequences. As part of the Paris Agreement, Indonesia set sustainability targets for the energy sector, where one of the biggest emitters is the national power system. Although the country set an ambitious strategy for reducing emissions from electricity generation, it is still dominated by coal consumption and is currently not on track towards meeting its sustainability targets. Policy measures and financial schemes stand as one of the most powerful ways to rapidly reduce emissions in the power system. This paper aims to propose policy measures and financial schemes for the Indonesian decarbonisation scene by analysing its key inefficiencies, the available international policy options and the national power system’s future projections.International examples prove to be useful implementations of the myriad of options when it comes to measures for the power sector. In terms of policy measures, Indonesia could make use of a liberalisation process to induce more competitiveness in the sector and drive down prices, while allowing easier access for private entities to enter the market. A CO2 tax or cap-and-trade system stand as the most effective standalone way to rapidly reduce emissions in the country, as it targets the most emitting sectors of the power system. Incentivising schemes like Feed-in-Tariff or net-metering foster generation technologies which may not be cost-competitive yet and do not have a sizeable role in the power mix now, but could play a big role in lowering emissions in the power system. These measures, however, pose the threat of raising the retail electricity price and ultimately hinder Indonesia’s ability to further develop economically.Financial schemes have the ultimate goal of facilitating access to finance for sustainable generation technologies and lowering risk for project developers. Attracting private and foreign investment is critical for the development of the power system in Indonesia. Using forms of lending like on-lending structure or loan syndication would promote larger spending in the industry while minimising risk. Further use of guarantees would attract a wider range of investments into generation technologies, as they would protect lending entities from potential risks when partaking in projects of this nature. Finally, the country would benefit greatly from the introduction of innovative financial schemes and business plans for the domestic solar energy industry, allowing Indonesia to tap into the great potential it has to disrupt the current state of affairs of the power system.

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  • 162.
    Ambhore, Dhairysheel Shivaji
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems.
    Navigating Industry 4.0 to Industry 5.0: Challenges and Strategies for Workforce Transition and its Relation to SDGs2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Fourth Industrial Revolution, known as Industry 4.0, has ushered in a new era of technological advancement and disruption across Manufacturing Industries. As organizations embrace digital technologies, artificial intelligence, and automation, the workforce faces profound changes in job roles, skill requirements, and training needs. Several challenges are faced by industries during this Industrial transformation. This research begins by focusing on Industry 4.0 and Industry 5.0, understanding there evolving concept. Through comprehensive literature review, the challenges and practices faced during this Industrial transformation and SDGs are discussed. Following the literature review, survey and interview questions were drafted trying to dug deeper into aspects that the literature could not fully capture. Furthermore, the relation between this Industrial Transformation and SDGs were established. This research contributes to a deeper understanding of the dynamic relationship between technology, the workforce, and sustainable development. This thesis report serves as a valuable resource for policymakers, business leaders, educators, and researchers seeking to navigate the transformative landscape of Industrial Transformation and its implications for a rapidly evolving workforce and sustainabledevelopment.

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  • 163.
    Ambrosson, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Selin, Markus
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Energianvändning i byggbodar2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Building operators in the construction sector has a history of not putting in resources to be energy efficient. Although as a result of new regulations and climate goals it has become important for building operators to be energy smart. As more buildings are virtually carbon dioxide free during their operational phase it has become crucial for construction firms to minimize energy use and thereby emissions during the construction phase. A large part of the energy used during the construction phase is used by the construction trailers on the construction sites. Construction trailers are intended to board and lodge construction workers during breaks and other free time.

    This work examines the possible energy savings that could be made by improving the construction trailers used today. This is accomplished by doing life cycle assessments on the poor present trailers but also on the new more energy efficient trailers that are coming onto the market. To broaden the study the non-efficient trailers are also analyzed with different types of improvements. The various improvements that are examined in the project are additional insulation, better windows, better doors, temperature control, sensor lighting and more. How to stack a construction trailer establishment optimally is also investigated.

    This is done by using a model that has been developed. This model is based both on simulations in the simulation program DesignBuilder and on calculations. The model investigates the energy use, the economic aspect and the carbon dioxide as a result of various additions to the construction trailer. To ensure the study is robust all simulations have been made on three locations in Sweden: Malmö, Stockholm and Kiruna.

    The results show that the energy use by construction trailers can be significantly reduced by supplementation. Sweden could save more than 2000 tons of carbon dioxide per year if the bad construction trailers in Sweden were improved in some areas. The results also show that temperature control is the improvement with the greatest impact on the total energy use for a construction trailer. This improvement also has the shortest payback time. It shows that the insulation related improvements provide greater reduction in energy use in northern Sweden than in southern Sweden. The work furthermore shows that the optimal surface for the trailer varies with the location of the trailer. How the trailer is positioned optimally relative to the cardinal directions also differ with the location of the trailer.

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  • 164.
    Ambrosson, Fredrik
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Selin, Markus
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Solar Concentrating Steam Generation in Alberta, Canada2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the context of climate change the world is facing an increasing need to become more environmentally sustainable, and a concerted effort to use renewable energy is required in order to decrease emissions, meet climate goals and prepare for the post-oil era. Solar energy is an area with great potential, and developments in solar energy technologies have increased rapidly. Concentrating solar technologies have existed for more than one hundred years, and have largely been applied in the context of direct power generation. However, solar energy technologies can also be used for purposes other than power generation, such as generating steam for alternative applications. This work investigates the steam generating potential of a solar steam generation system located at the Southern Alberta Institute of Technology (SAIT) campus in Calgary, Alberta, Canada and the potential for utility scale implementation in Alberta’s Oil Sands for steam demanding enhanced oil recovery (EOR) methods. Furthermore, this thesis also validates weather data for the SAIT campus.

    Both of the proposed systems use parabolic troughs as solar collectors. The SAIT system also incorporates a two-tank direct thermal energy storage and Therminol 62 as the heat transfer fluid, while the utility scale system uses water as the heat transfer fluid.

    The results show that the SAIT system can provide saturated steam at 0,7 MWh 155 times which amounts to a total steam output of 90 MWh annually. The results for the utility scale system show that solar steam generation from a 500 MW thermal plant implemented for enhanced oil recovery in an EOR facility becomes economically feasible, as compared with steam production from natural gas, at a natural gas delivery price of approximately $7 USD/GJ. Furthermore, an installed 500 MW thermal plant can reduce carbon emissions by 180,000 tonnes of CO2 equivalents annually.

    Conclusions drawn in this thesis are as follows: the technology is technically feasible however there are both political and economic obstacles to its use; solar EOR should be seen as an add-on to existing plants due to the intermittence of solar energy in Alberta; the GHG reduction potential is great and consequently there is a possibility of receiving carbon credits by using the technology; and by tilting the solar collector field total output can be increased by over 25%.

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  • 165.
    Amindezfooli, Soroor
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Analysing the Effect of Angle of Attack on Turbulence Intensity, Wake and Power Production for Hexicon Floating Platform2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When the wind passes through the wind turbine, it losses a part of its energy and as a result a low momentum region creates behind the wind turbine that refers to the wake.  This effect is more significant in a wind farm, where a group of wind turbines are located close to each other in a specific region. Since the wind speed slows down after passing the first row of the turbine, the other rows at the downstream experience lower wind velocity and consequently they can capture less energy in the wind. Wake effect influences the annual power production of a wind farm, not only because of the reduction in the wind velocity but also because of creating  turbulence in the flow and generating more vibration loads on the rotors which can reduce the lifetime of the turbines and increase fatigue on the blades.  Also when the Angle Of Attack (AOA) changes the shape of the wake varies which influence the annual power production and turbulence intensity of a wind farm. 

    The main purpose of this work is to investigate the effect of changing the AOA on the annual power production and the turbulence intensity of Hexicon platform. For this aim, different AOA between zero and 15 degrees are considered in the simulations.

    ANSYS CFX is applied to model the wind turbine configuration and simulate the fluid flow in different wind direction using unstructured meshing method. In addition wind characteristics profiles such as mean wind velocity, turbulence intensity and length scale at different height are imposed at the inlet of the domain to present the Atmospheric Boundary Layer (ABL). RNG k-ε model is implemented for turbulence modeling. In addition roughness modification is utilized in simulation to get more accurate results in terms of turbulence intensity. 

  • 166.
    Amirault, Corentin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Load Forecasting in Rural Area in Developing Countries2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper presents the coding of a software designed to forecast the electric load in rural area indeveloping countries. This software aim is to provide a tool for planning rural electrification. It considersvillage has unit of study and distinguish in each village the main consumers; namely poor, medium andrich households, infrastructures, services and specific demands (big SMEs, industries). For each of theseconsumers, the load curves are entered as key input to compute the total demand of villages in term ofenergy consumption, peak demand and total load curves. Each village belongs to different study areawhere input parameters differ; the merging of all studied areas can cover an entire country. Calculationsare done year by year for a typical duration of 20 years. This work has been declined to feasibility andimplementation tools.The work done for this master thesis also includes the organization of a survey campaign dedicated incollecting data in Tanzania to feed the load forecast model built previously. To conduct this survey aspecial excel database based on interactive forms has been built

  • 167.
    Ammari, Ali
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Experimental Investigation ofTwo-phase Flow in Microchannels“Co-current Absorption of Ammonia in Water to Design an Innovative Bubble Plate Absorber”: “Co-current Absorption of Ammonia in Water to Design an Innovative Bubble Plate Absorber”2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    For ammonia-water absorption refrigeration technology it is suggested to use bubble type absorbers because the higher contact surface area provides a higher mass transfer rate. Furthermore, dispersion of bubbles in the bulk of liquid phase also exhibits better heat transfer characteristics that facilitate the recovery of dissipated heat of the exothermic absorption.In this context, plate heat exchangers are believed to be an option to be employed as absorber in some applications. Commercial plate heat exchangers have only one inlet and outlet for a working fluid and as a result, gas and liquid should be mixed before supplied to a gap between the two adjacent plates. The consequence is the high risk of bubble mergence to form a bigger bubble and to follow the shortest flow paths in vertical direction so that not all the heat transfer surface can be effectively used. Furthermore this feature makes plate heat exchangers sensitive to the angle of plate relative to the vertical which would be worst when it is laid to its side on a horizontal plane.Austrian Institute of Technology (AIT) develops an efficient Bubble Plate Absorber for applications in high-pressure absorption systems and this work tries to investigate design possibility of this Bubble Plate Absorber based on a plate heat exchanger equipped with microchannels between plates.Two sets of seven parallel microchannels same in shape and dimension were tested. The first set had a continuous wall which means fluids could flow independently along the microchannels; whereas, the other set was benefiting from some linkages between channels that fluids could cross from one microchannel to another one. Ammonia vapour was injected via one and two-holed distributors.It was found that microchannels with continuous wall deliver higher concentration and less unabsorbed bubbles at the microchannels outlet. In visual analysis by high-speed camera, changing the vapour distributors from single-hole to double-hole had no significant effect on the bubble distribution quality in lower flowrates; however, double-hole vapour distributor showed better performance in higher vapours flowrates.

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    Ali Ammari, 2012, Experimental Investigation of Two-phase Flow in microchannels
  • 168.
    Amnäs, Ulrika
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Gårdh, Moa
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Plasmaförgasningsanläggning för bio-jetbränsle till Bromma flygplats: En tekno-ekonomisk konceptstudie2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    IPCC has estimated that the aviation industry is responsible for two percent of all man made carbon emissions (IPCC, 2007). An expected increase (ICAO, 2013) of this share puts the aviation industry in front of big challenges for the future. The main obstacle lies within how the industry can grow but at the same time decrease their carbon emissions.

    As a first step to meet this challenge this report examines a potential pilot plant in connection to Bromma Airport that will provide the airport with bio-jet fuel. The jet fuel will be produced through plasma gasification and through catalysation with biomass as raw material. The total production is assumed to be 50.000 tons of fuel per year, which would make Bromma Airport completely neutral with carbon emissions. The report focuses on the techno economical aspects of a plant and is aimed to investigate if the plant is profitable or not.

    The purpose of the report is to give a realistic image of the economical consequences for Swedavia AB in the event of setting up a pilot plant in connection to Bromma Airport. This is done by estimating the total investment- and production costs as well as by comparing the calculated competitiveness of the bio jet fuels with todays’ fuel prices. In order for the report to give a satisfactory image of the pilot plant from a techno-economical point of view the report also investigates possible financing models.

    The studys’ results have been ascertained by dimensioning the plant based on comparisons with a number of reference projects. The configuration of the plant form the basis of the calculations which have been done to estimate the fuel production, the need for raw materials, electricity production and consumption as well as the total investment- and production costs. To get results for the pilot plants profitability, a price for bio jet fuel and net present value (NPV) has been put together. The financing models, which have been developed and investigated, derives from information given by Swedavia AB, as well as comparisons with existing models from already existing projects. 

    The result, which this study has accomplished, is that the pilot plant investment costs are expected to reach approximately 6440 MSEK. Production costs were calculated to be 1250 MSEK, which made the fuel price 6,1 SEK/liter. The NPV for the pilot plant, with the assumed yield requirements of nine percent, the operating time 8000 hours per year and the financial support from Energimyndigheten on 25 percent, was calculated to -285 MSEK with a payback time of 27 years. As the technical life was assumed to be 25 years it could be concluded that the pilot plant with these assumptions would not be profitable. 

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  • 169.
    Anand, R. S.
    et al.
    Karunya Inst Technol & Sci, Dept Mech Engn, Coimbatore, Tamil Nadu, India..
    Jawahar, C. P.
    Amity Univ Madhya Pradesh, Dept Mech Engn, Gwalior, India..
    Bellos, Evangelos
    Natl Tech Univ Athens, Sch Mech Engn, Athens, Greece..
    Malmquist, Anders
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    A comprehensive review on Crossflow turbine for hydropower applications2021In: Ocean Engineering, ISSN 0029-8018, E-ISSN 1873-5258, Vol. 240, article id 110015Article, review/survey (Refereed)
    Abstract [en]

    A Crossflow turbine is a device used to generate power from hydro, which is a renewable source of energy. The salient feature of this turbine is its simplicity in construction. In the past few decades, variables such as flow diverter, air holes, bidirectional flow were introduced in the turbine design to improve its efficiency. This paper presents a comprehensive review of the performance of the cross flow turbine. The review of literature is classified into experimental and numerical studies. The present study highlights the optimum range of geometrical variables required for the efficient design of a cross flow turbine. The study also emphasizes the importance of employing the cross flow turbine in remote places where run-of-river hydro power plants are feasible, as it provides a low-cost energy solution. The outcome of the present study will help the researchers to identify the research gap based on the present status of work done and to improve the performance of the cross flow turbine further in the future.

  • 170.
    Anantapatnaikuni, Srikant
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Enhancing Energy Efficiency and Renewable Energy in the future electricity system of Odisha, India2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    India ratified the Paris Agreement in 2015. The country’s Intended Nationally Determined Contributions includes reduction of emissions intensity by 33-35% in 2030 from the 2005 level and 40% of renewable energy share in the electricity mix by 2030. This study evaluated the future electricity system of Odisha, one of the states in India that is rich in mineral resources. It holds 26% of India’s coal reserves. While the current electricity system of Odisha comprises 95% of coal power generation, the state’s commitments in terms of climate goals and increasing the deployment of renewable energy sources (RES) (i.e., 3 GW by 2022) are aligned with the national goals. To encourage investment in RES and to reduce investment risks, Odisha has also set targets for renewable purchase obligations for utilities and captive consumers. They have to procure 15% of their total electricity consumption from RES (8% solar and 7% non-solar sources) by 2022. The electricity demand in the state is expected to increase due to increased economic growth and the goal to reach 100% energy access (24x7) to households. Besides, there is huge potential for energy savings in the current electricity system through improvement in energy efficiency in the end-use. The increase in electricity demand, high share of fossil in current electricity system, renewable energy target, climate goals and lack of study at the state level are the reasons to assess the future electricity system of Odisha. The study investigated the electricity system in Odisha to meet the increased electricity demand from 2018 until 2050. It estimates the technical, economic and environmental impacts of enhancing energy efficiency and renewable energy on future electricity system of Odisha by using the Long-range Energy Alternatives Planning System. Odisha’s future electricity system is assessed in four scenarios i.e. no new policies introduced in the future (BAU), high renewable energy share (HRE), improvement in energy efficiency (IEE) and a combination of renewable energy and energy efficiency (CER). The result shows that the energy requirements in the IEE scenario are 26% lower than in the BAU scenario, and the total costs are lower than HRE scenario by 34% and CER scenario by 10%. The CO2 emissions of the IEE scenario are higher than HRE scenario by 10% and CER by 23%. In the HRE scenario, the total costs are higher than BAU scenario by 8% and CER scenario by 26%. The CO2 emissions are lower than BAU by 45% and IEE by 25%. In the CER scenario, the costs are lower than BAU by 20% and HRE by 26%. The CO2 emissions are lower than BAU by 60%, IEE by 44% and HRE by 26%. The energy savings can be achieved by continuing the existing scheme Ujala for subsidised LEDs, extension of Perform Achieve Trade (reduction of specific energy consumption) scheme to medium and small industries. The renewable targets can be achieved through continuation of RPO which reduces the risk of new investors. Capacity auctions could bring down the solar and wind tariffs. The study demonstrate that the RPO for 2022 cannot be achieved with the target RE capacity. The gap must be fulfilled by either procuring renewable electricity from the regional grid or buy renewable energy certificates from the market.

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  • 171.
    Ancel, Julie
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Improvement of the electrical part of Idénergie's hydrokinetic turbine2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Idénergie develops the first domestic hydrokinetic turbine for rivers. Itaims at producing about 100W in a 1.4m/s river to power up remote locations.Idénergie’s turbine has two main advantages: a completely watertight shaftlessgenerator and an integrated smart converter. The first turbines are planned tobe sold in June 2014.To be able to test the embedded intelligence in the lab, Idénergie’s testbench must be able to reproduce river conditions. Measurements have beenperformed in a river and provide the torque developed by the river at differentspeeds. On the test bench controlled by a LabView program, the rotationalspeed is measured and the corresponding torque computed. This torque is setas the new command and makes the test bench behave as if it was driven by aturbine in a river.Idénergie’s generator contains a rotor made of permanent magnets.These magnets are provided by a supplier and their quality needs to bechecked. For this purpose, a magnetometer is designed and built. It contains 5Hall effect sensors which move at a constant speed above a magnet andmeasure its magnetic field. The magnetometer is able to compare magnets to areference and to detect the faulty ones. The sensors are also used to measurethe magnetic field of the rotor and show that the custom-made shape of themagnets has no influence on the sinusoidal field.The converter transforms the three-phase current to direct current andcontrols the rotational speed. This is done thanks to an embedded electroniccard, which is about to be working properly. The Maximum Power PointTracking algorithm ensures that the rotational speed is optimum in order toproduce the maximum power output. The code loaded on this card is written inits main part but needs to be tested on the test bench once the card will beoperational.

  • 172.
    Andersen, Filip
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Lagergren, Pontus
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Product and Service Design.
    Compliance i verkligheten: En fallstudie av ÅF PRS2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Antalet miljödirektiv fortsätter att öka och de befintliga kompletteras regelbundet med nya krav och regler. ÅF har tillsammans med industrin och dess leverantörer utvecklat ett verktyg, ÅF PRS, för att handskas med de problem direktiven skapar för företagen. Syftet med detta arbete var att identifiera företags nuvarande processer för hantering av direktiven REACH, RoHS och ErP och föreslå förbättringar av PRS i linje med det som identifierats.

    10 företag valdes ut baserat på omsättning och antalet anställda. Ett krav var att de skulle vara verksamma på den svenska marknaden. Bland företagen återfanns både sådana verksamma inom industrin och detaljhandeln. Metoden som valdes för arbetet var kvalitativa intervjuer av ansvariga inom miljöområdet.

    PRS, Product Regulatory Support, är ett webbaserat verktyg för företag att samla in information från sina leverantörer. Det hjälper företagen genom att automatisera insamlingen av information och möjliggör för företagen att snabbt få överblick om dess produkter är compliant – uppfyller lagar och regler.

    Studien visade att företag inom detaljhandeln kommit längre i sitt arbete med complaince än de inom industrin. Detaljhandelsföretagen menade att de kommit långt i sitt arbete och att de flesta av de produkter de sålde uppfyllde de olika direktiven. Bland industriföretagen var processen att implementera miljöarbetet i organisationen mycket olika långt gånget. Det fanns exempel på dem som precis startat men även ett som ansåg sig ha full information om alla sina inköpta artiklar.

    Analysen av det insamlade materialet visade tydligt att ÅF PRS fyller ett syfte på marknaden. Intervjuerna visade dock att verktyget kunde utvecklas ytterligare för att bemöta de olika företagens behov och företagsstrukturer. 

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  • 173.
    Andersson, Alexandra
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Idstam, Patrik
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Från alger till biodiesel - Den italienska drömmen?2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project aims to investigate whether algae can be used for biodiesel production in Italy. Algaes are a good option since they are fast growing and do not occupy arable land.

     

    The aspects that have been considered are growing, harvesting, which algae strain that is most suitable, extraction of oil, the production of biodiesel and where in Italy this could be possible due to climate. Cost– and energy calculations have been made to investigate if biodiesel produced from algae would be profitable.

     

    During the production of biodiesel there are several residues obtained. When the oil has been extracted from the algae, biogas is produced from the residual biomass by anaerobic digestion and then the electricity that can be produced is supplied to the production of biodiesel. When the oil is converted into biodiesel it also produces glycerine that has multiple uses and is sold to other companies. The carbon dioxide that is supplied to the algae is transported from nearby industries, so the cultivation is contributed to reduce carbon emissions in the area.

     

    The obtained results show that it is not economically viable to produce biodiesel from algae in Italy today. The price per tonne has been calculated to € 1 919 that can be compared to the price per tonne for biodiesel produced from palm oil which is € 574. The energy calculations show that it would require 3.93 MJ to produce 1 MJ of biodiesel with today’s technology.

     

    To lower the costs it is primarily the investment costs that need to be reduced and this is expected to happen when the technology advances. In order to improve the energy balance the energy amount extracted from the waste products must increase.   

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  • 174.
    Andersson, Carl
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    An experimental study of surface coatings to limit the impact of frosting2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Heat pumps are commonly used as a way to efficiently meet heating demands. The efficiency and flexibility of Air-source heat pumps (ASHPs) have improved in recent years and is an attractive heating solution suitable for houses with lower heating demands, as it is inexpensive to purchase and install compared to other heating solutions. However, ASHPs have a significant drawback as frost builds up on the evaporator surface in certain conditions, reducing both the heating capacity and efficiency, and therefore requiring regular defrosting to restore performance. Moreover, improvements for heat exchanger designs allowing for more compact and efficient units have not been able to be fully utilized in frosting conditions, as they are more quickly blocked by the buildup of frost and have poor meltwater drainage during defrosting.This thesis aims to experimentally investigate the potential of hydrophilic and hydrophobic surface coatings to minimize the negative performance impact of frosting in Air-source heat pumps. A literature study was performed as a basis for the experiments, covering previous research on how frosting affects the performance of heat exchangers and ASHPs, methods, and control strategies for defrosting as well as a theoretical background of the mechanisms governing condensation, frost formation and growth, wetting and intended working principles of the tested surface treatments.A test rig consisting of a wind tunnel inside a climate chamber was modified, and an automated defrost control was implemented based on the reduction in air velocity. Seven different surfaces: one superhydrophobic, five hydrophilic (one superhydrophilic, four hydrophilic foils), and one uncoated aluminum surface were tested in frosting conditions over multiple cycles of frosting and defrosting. Test conditions were held stable at a climate chamber set-point of 2 °C, 84 % RH and an initial air velocity over the test plate of 2 m/s. Data was collected, and the performance was compared in terms of duty cycle, (defined as the quotient between time operating in cooling mode and the time for a full cycle) and observations were made regarding differences in behavior during frosting and defrosting.Test results showed that there was a clear difference between the different types of surfaces. Over cycles 10-25 the five hydrophilic surfaces performed the best, having an average duty cycle of 0.83; compared to the uncoated aluminum surface (0.69) and the superhydrophobic surface performing the worst with a duty cycle of 0.56. A gradual drop in duty cycle was observed for all of the tested surfaces, both from a shorter runtime and increased defrosting time. The variance in defrosting time was small between cycles; however, there was a larger variation in runtime between individual cycles. Some visual observations of the behavior during frosting and defrosting on the surfaces, such as the buildup of remaining meltwater after several defrosting cycles were analyzed and discussed in relation to the measured performance.

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  • 175.
    Andersson, Edwin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Cooperation for Heat Recovery: A Case Study on Heat Utilization From a Supermarket Refrigeration System2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The study looks at heat recovery of a refrigeration system in a supermarket where the heat was supplied to apartments in the same building. Such a system requires cooperation between the supermarket owner and the property owner, with both having different motives. By gaining understanding of each other's needs and obligations, cooperation can become easier to achieve, with a result that is more optimal for both actors. Heat recovery for use within the supermarkets has existed for a long time, though supplying the heat to other actors is not as common. Using CO2 as refrigerant is becoming more popular in supermarket refrigeration systems, which allows for achieving higher temperatures in recovered heat, enabling use in radiator systems or for preheating domestic hot water. In lack of other cooling solutions, the supermarket studied in the project had previously used municipal water for cooling of the condenser in the refrigeration system, which is a costly solution that does not utilize the heat. The amount of heat that can be recovered was estimated and compared to the varied amount of heat demand in the supermarket and the rest of the property over a year. Findings show that heat recovery from the refrigeration system create considerable cost savings for both the supermarket owner and the property owner, despite still requiring cooling with municipal water during summer. Financial compensation for delivered heat is difficult to argue for at moment, though it may become relevant if new solutions for cooling of the refrigeration system are proved to be feasible.

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  • 176.
    Andersson, Felix
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Lindstrand, Nils
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Teknoekonomisk analys kring möjligheten att ersätta Ringhals kärnkraftsreaktor II med hållbar elproduktion2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this report is to analyze how the nuclear power plant reactor Ringhals II can be sufficiently replaced with renewable energy sources. This is done by evaluating and analyzing the energy sources that are commercially viable on scale in Sweden and mapping their geographic and technical potential in the region surrounding Ringhals that is Halland and Västra Götaland. The effects of the replacement energy mix on the electricity grid is then simulated for every hour over a year in order to see, to what extent, production will be able to meet consumption in the region as well as what transmission pressure from other regions the grid will be subjected to. From the given energy mix it is then evaluated whether or not production cost will increase and what the new production cost will be.

     

    The results shows that the suggested energy mix will be able to replace the second reactor in the nuclear power plant Ringhals with only a marginal increase in transmission to and from the region. It will also lead to a somewhat lower production cost with the production methods suggested however the increased transmission pressure on grid could lead to significant investment costs. The energy mix that is suggested is made up of a total increased yearly electricity production of 5 TWh from wind power, 1,75 TWh from cogeneration and 0,05 TWh respectively from hydro- and solar power.

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  • 177.
    Andersson, Frida
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Sahlsten, André
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Studie av åtgärder för att öka värmefaktorn för bergvärme till en villa: Genom forcerad konvektion över värmekälla samt flödesoptimering i borrhålskrets2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report contains a study of a downhole heat exchanger and it’s . The system has two boreholes connected by a by-pass valve which makes it possible to vary the flow in the boreholes and the heat exchanger. In addition to that the radiators have radiator fans installed underneath them. These radiator fans will contribute to an increase in the heat transfer between radiator and room. Measurements of the heat transfer have been done both with and without the radiator fans operational. The flow in the boreholes was kept constant to measure the impact on the energy taken from the boreholes.

    To measure the type of flow in the boreholes which gave the highest, two different operating cases were tested, one with laminar flow and one with turbulent flow. This to examine how the type of flow impacts the heat transfer between the ground and heat carrier fluids and by that determine in which case the highest  is obtained.

    The result shows that a greater  is obtained when the radiator fans are operating than when they are not, and that a turbulent flow gives a higher  than a laminar flow. To obtain the highest possible value for  the case with operating radiator fans should be combined with case for turbulent flow.

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  • 178.
    Andersson, Hanna
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Potential of Implementing Power-to-Methanol Projects Based on Biogenic Carbon in the Nordics2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Urgent CO2 mitigation strategies are crucial to combat climate change. Power-to-X encompasses the conversion of renewable electricity into carbon-neutral fuels, such as hydrogen and its derivatives. E-methanol, both an e-fuel and a platform chemical, can be obtained by combining hydrogen with biogenic CO2. Moreover, e-methanol holds the potential to defossilize both heavy transportation and chemical sectors, by reducing the reliance on fossil fuels. Sweden and Finland are global leaders in the wood processing industry, offering substantial potential for capturing and utilizing biogenic CO2 emissions from industrial flue gases in e-methanol production. The pulp and paper industry and the energy sector with combined heat and power plants are identified as the best point sources for biogenic emission capture in Sweden and Finland, due to their substantial use of biomass and biofuels. The thesis comprises a quantitative analysis with cost curve calculations to identify the key cost drivers of a power-to-methanol project. Additionally, a qualitative analysis is conducted to examine other important aspects influencing the project’s feasibility, such as power plant availability, environmental benefits, and grid availability. The levelized cost of e-methanol is calculated to range from 1,873 to 951 €/t depending on production capacity and electricity price area, compared to the current market value of fossil methanol estimated at an average of approximately 250 €/t. The key cost drivers for e-methanol projects include initial investments in technologies such as water electrolysis and carbon capture technology, as well as potential requirements for seasonal CO2 storage. A project’s geographical location will also impact production costs due to fluctuating electricity prices and grid availability in different electricity price areas. Among these areas, price area FI turned out to be the most feasible, while SE1 and SE3 are considered the least feasible regions for implementing a power-to-X project. Nevertheless, power-to-methanol presents an opportunity for the establishment due to society’s dependence on carbon. However, due to the high production costs, the realization of a power-to-methanol project might be infeasible without financial support, subsidies, and regulatory frameworks promoting and increasing the demand for sustainable and environmentally friendly fuels.

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  • 179. Andersson, K.
    et al.
    Granryd, Eric
    KTH.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Water to water heat pump with minimum charge of propane2018In: Refrigeration Science and Technology, International Institute of Refrigeration, 2018, p. 725-732Conference paper (Refereed)
    Abstract [en]

    This paper describes the technology for an environmentally friendly ground source heat pump for a single family home, characterized by using pure water as coolant and propane as refrigerant. The objective was to build a test system, operating under realistic conditions, using less than 150 g of propane, providing at least 5 kW heating capacity with reasonable efficiency and without freezing the coolant water. The borehole heat exchanger was of coaxial type, providing about half the thermal resistance compared to a standard U-tube collector (Acuña 2010). The evaporator and condenser where asymmetrical plate heat exchangers with small channel height (< 1 mm) on the refrigerant side. They were developed and manufactured exclusively for this project with a new type of press pattern, including a special, small volume sub-cooling section at the end of the condenser. A DC-motor scroll compressor for AC in electric vehicles was used, characterized by small internal volumes, small oil charge and wide capacity range (800-9000 rpm). A PAG-type oil was used, which however seemed to cause some problems with heat transfer and pressure drop in the evaporator. The system also included a specially built mini channel liquid/suction line heat exchanger and a standard thermostatic expansion valve. The paper presents test results for a heating capacity range of 2-10 kW. The performance was reasonable in this range with a charge of 100 g of propane (-1<T2<5°C, 30<T1<55°C). The charge that is required is determined at the lowest capacities, at low compressor speed and high evaporating pressures. A lower charge is beneficial at higher capacities.

  • 180.
    Andersson, Lena
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Singeltubvärmeväxlare för EGR-applikationer2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 181.
    ANDERSSON, LOA NIKLAS PATRIK
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    SAG, JAN JACK
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Biogasuppgradering: En studie om uppgraderingstekniker av biogas2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report discusses upgrading techniques for biogas, with a particular focus on upgrading with two different kinds of water scrubbers. More precisely a conventional water scrubber’s features and profitability are compared to a relatively new version of a water scrubber called Biosling. Biosling’s unique characteristic is its combination of a conventional water scrubber column and a hose reel called Bioslingpump. A literature study about different upgrading techniques, the production of biogas and the usage of biogas in Sweden today forms the basis of the comparison. The method is to compare input data from the different upgrading plants and to produce graphs and charts using Matlab to draw conclusions about which water scrubber is more profitable in terms of water consumption, payback time, raw gas capacity and electricity consumption. The results show that a conventional water scrubber is more profitable than Biosling. A failure in the comparison is that the calculation assumes that the plants operates at maximum capacity the whole time, which is not normal. Despite this, we conclude that it is more profitable to upgrade biogas with a conventional water scrubber, although Biosling is a good alternative for small-scale upgrading. One suggestion for improvement for Biosling is to remove the conventional water scrubber column and thereby minimize the electrical consumption and investment costs.

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  • 182.
    Andersson, Martin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Comparison of solar thermal and photovoltaic assisted heat pumps for multi-family houses in Sweden2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The building sector account for 40 % of the global energy demand, and an increasingly popular way to supply buildings with heat is through the use of heat pumps. Solar thermal (ST) can either be used as a low temperature energy source in the heat pump or to directly supply the building’s heating demand. 

    The increasing market of PV has made it a favorite for roof-top solar installation. Its physical integration with buildings and HPs is simpler than that of ST and can supply any available electric load associated with the building and not just the HP system. It can also supply any excess power to the grid. 

    In order to properly compare these two options, key performance indicators (KPIs) were identified for several system boundaries within the building and HP system. Technical KPIs used were seasonal performance factor (SPF), solar fraction (SF) and self-consumption (SC), while internal rate of return (IRR), net present value (NPV), profitability index (PI) and payback time was used to evaluate their economic performance. 

    For the thesis a multi-family house was modelled in TRNSYS where different system sizes of either ST or PVs was simulated for a year with three-minute intervals. The ST was connected in a parallel configuration thereby supplying the building’s domestic hot water (DHW) through a separate storage tank. The modelled heat pump was a ground source heat pump (GSHP) which utilizes boreholes as the low temperature energy source.

    The SPF increased for both the ST and PV integration from the reference scenario (no PV/ST integration) but to a varying degree depending on the analyzed system boundary. The economic results suggested that PVs are the more financially sound option over ST for the simulated MFH. The sensitivity analysis also showed the large impact of economic assumptions on the expected profitability for both the PV and ST systems. Based on the results would the simulated MFH with an existing GSHP benefit more from installing PV instead of ST from both a technical, economic and environmental perspective. 

    It is reasonable that PVs will most likely be an integral part for future buildings in Sweden with or without HPs because of its financial strength and versatility of demand supply, especially compared to ST.

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  • 183.
    Andersson, Mattias
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nurmos, Ville
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Hållbara energilösningar för Sala silvergruva: En studie av energisystemet och effektiviseringsmöjligheter2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sala Silvergruva AB is one of many companies currently struggling with high energy prices. This thesis examines what possibilities there are to create a sustainable energy system for Sala Silvergruva considering economics, environment and social aspects.

     

    The report examines nine technologies; wind power, hydropower, solar capture, solar cells, pellet boilers, heat pumps, energy efficiency and storage of heat from greenhouses or district heating. These technologies are analyzed from ten different aspects representing the sustainability demands. In the analysis recommendations are given according investment to each technology. The thesis culminates in a result map which clearly indicates what requirements the various techniques fulfill. The following discussion will lead to a conclusion that present the steps to be taken in order to create a sustainable energy system for Sala Silvergruva AB.

     

    Pellet boilers and heat pumps show to currently be the most resilient solutions. Due to the age and properties of the houses energy-efficiency investments should also be made. These investments are expected to be repaid in 1-5 years.

     

    There are financial incentives for the local energy company Sala-Heby Energi AB to build storage for district heating water in the mine. Such a solution is found to create benefits for both the Sala Silvergruva AB region as a whole. Payback time for the investment is for Sala-Heby Energi AB between 4 to 12 years, depending on size of the storage.

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  • 184.
    Andersson, Sanna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Edfeldt, Erica
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Lönsamhetsanalys för svenskproducerat biojetbränsle baserad på alger2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today’s transportation sector is in a path dependency of the using of fossil fuel. This is problematic since there are limited oil sources in the world and since the use of fossil fuels increases the green house effects. According to EU’s climate goals the emissions of green house gases should be reduced by 20 percent by year 2020. The European emission trading system, which the airline industry will be a part of from 2012, raises the incentives for companies to lower their emissions. Airline companies will therefore be more likely to add a certain percentage of biofuels into their aircraft engines. A lot of research and development is currently being made about the second generation of biofuel. One raw material for a second generation biofuel is algae, which is believed to have great potential due to the fact that it can be cultured on marginal land, fast growth rate, high oil content and consumes carbon dioxide while growing.  The aim with this report was to create a picture of the opportunities in Sweden to economically feasible produce algae biofuel for aircraft, from which continuous research can be made. The goal was to create an evaluation of whether it is profitable or not to have a production with carefully chosen growth facility, algae specie, harvest method, drying method and other refining steps. The market was first evaluated and found to be attractive, using the model of Porter’s five forces. Different decisions regarding the production was made based on interviews, information found in report databases and search engines online and based on the study visit at Käppala wastewater treatment plant. These decisions and the costs they are associated with were later used in the model.

     

    A competitive bio jet fuel price year 2020 is regarded to be the price on fossil jet fuel plus the cost for the related certificate of emission cost. In the model’s main scenario the competitive liter price year 2020 was calculated to be 7.2 Swedish kronor. The growth facility was designed as an open raceway pond integrated in a wastewater treatment plant, since the wastewater contains nutrition and carbon dioxide used in the algae photosynthesis. The algae specie chosen was Chlorella Vulgaris. The production will run every year from June to September and the produced volume is estimated 60 400 liters of bio jet fuel each production season. The yearly sales in the main scenario, including the money the wastewater treatment is paying for lowered carbon dioxide emissions, are estimated at 455 100 Swedish kronor. By altering the price of fossil fuel and of emission trading certificates four different scenarios were created. The production will begin in 2017 and the result was calculated for the first seven years based on the yearly income and the estimated start-up costs and running costs. The result turned out to be negative or just above zero for all four scenarios. The project was profitable at the price 10.8 Swedish kronor per liter with a positive net current value over seven years and internal rate of return at 15 percent. The payback time was calculated to be four years at the most.

     

    Whether or not it is possible to charge 10.8 Swedish kronor per liter is not certain. However, this is the price needed in order for the project to be profitable. Otherwise external changes are needed such as increased raw oil prices, successful research and development in the field of algae bio fuel production or increased political incentives in favor of bio fuels. Environmental costs and environmental gains with an algae fuel production as well as proposals for further efficiency are suggestions on further work that need to be done on this field.

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  • 185.
    Andersson, Simon
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Analys av energisimulering från projekteringsskede och verklig energianvändning i lokalbyggnad.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Idag sker ett kontinuerligt arbete med att reducera energianvändningen i byggnader under desslivscykel för att minska miljöbelastningen och utnyttjandet av fossila energikällor. En reduceringav energianvändningen utgör även ett ekonomiskt incitament genom minskade energikostnader.Inom byggsektorn arbetar flertalet företag med olika former av miljöcertifieringar såsomMiljöbyggnad, LEED och BREAM. En viss del av bedömningen bygger på en energisimuleringav projekterad byggnad, ett scenario av framtida energianvändning.

    Energisimuleringar utgör ett beslutsunderlag och kan användas under hela byggprocessen menlämpar sig främst under projektering då flertalet beslut rörande olika faktorer såsom klimatskal,ventilationssystem, värme och kyla samt framtida drift och styrning behandlas.

    I detta examensarbete analyseras energianvändningen i fastighet BioCentrum i Uppsala utifråndriftår 2012 och jämförs mot projekterade värden från tidigare energisimulering. En jämförelsegörs även mellan indata och antaganden samt projekterade energiflöden för värme, komfortkyla,processkyla och el. Att arbeta med energisimuleringar under projektering är en kontinuerligprocess och på vilket sätt detta verktyg kan förbättras i projekteringsarbetet diskuteras. Tre faktorer har behandlats, vilka är utomhusklimatets påverkan på energianvändningen, drift ochstyrning av olika system inom fastigheten samt brukarens beteende och verksamhet. Med hjälp avunderlag från driftår 2012 genomförs en uppdaterad energisimulering för analys och jämförelse.

    För fastighet BioCentrum syns en tydlig ökning av både värme och kyla samt el i jämförelse medprojekterade värden. Orsak till detta är i många fall verksamhetsanknutet genom ökade driftstider,förhöjda luftflöden i ventilationssystem samt en varierande verksamhet inom byggnadensom kräver ett stort behov av el, men även kylning av dess interna laster. Störst påverkan påresultatet från energisimulering har bedömningen av den verksamhetsanknutna internvärmensamt luftflöden i laborationslokaler.

    Tre resultat som verifieringsprocessen sammanställer är hur mätarstrukturen i drift fungerar, vilkaförändringar som skett under produktion i förhållande till projektering samt hur verksamhetenidag utnyttjar och styr de tekniska systemen. Till stor del en verifiering av projekterad data.

    Genom uppföljning och verifiering skapas en nulägesbild över energianvändningen, vilkettillsammans med identifierade energieffektiviserande åtgärder skapar ett bra beslutsunderlag förframtida investeringar.

    För att förbättra projekteringsprocessen av framtida energianvändning och verifieringsprocessenär det viktigt att tydligt definiera vilka antaganden som genomförts under projektering samt vilkaprocesser som ingår i bedömning av specifik energianvändning. Att samredovisa underlag ochresultat möjliggör för en bättre uppföljning av nyckeltal och underlättar för förvaltning attoptimera och följa upp olika processer och system inom fastigheten.

    Sammanfattningsvis är hjälpmedel såsom energisimuleringar ett viktigt verktyg underprojekteringsprocessen och skapar ett scenario över framtida energianvändning. Detta arbetevisar på den komplexitet som finns vid uppföljning av energianvändningen inom lokalbyggnaderoch att ett bra samarbete mellan konsulter, beställare/fastighetsägare och hyresgäst är nödvändigtför att uppnå ett bra energiarbete under projektering och sedermera drift av fastigheten.

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    Analys av energisimulering från projekteringsskede och verklig energianvändning i lokalbyggnad
  • 186.
    Andersson, Simon
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Listén, Martin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Life Cycle Impact Assessment: A comparison of three contemporary methodologies2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis compares the Ecological Scarcity Method 2006, EPS 2000 and ReCiPe 2008, three contemporary methods for life cycle impact assessment, in order to provide a better understanding of what differentiates the methods, with regards to application and ideological standpoint.

    A basic understanding of the environmental situation, as well as life cycle assessment is given, and it is shown that life cycle impact assessments - attempts at quantifying the total environmental impact over the entire life cycle of a product or process - is  of relevance regarding the current environmental challenges.

    In a qualitative comparison, it is shown that, while the approaches to impact assessment differ, the methods follow over time increasingly similar mathematic formulas.

    A quantitative comparison between the models, where the total presumed effect of certain impact parameters is compared to that of carbon dioxide, shows that while several outliers are observed, similarities appear to be strongest across methods using either the midpoint or the endpoint approach.

    A case study of the estimated impact of each method using hard coal and peat, as well as nuclear power and wind power as energy resources, show that the results sometimes differ greatly. It is therefore concluded that knowledge about the methods is of great importance when choosing what LCIA method to use for certain applications.

    It is also concluded that the ecological scarcity method is most suitable for use when a strong connection to political targets is of importance. It is further found that the EPS method can provide valuable guidelines for policy makers and political activists. It is finally concluded that the greatest strength of ReCiPe is that it allows reviewing products with regards to different ideological perspectives.

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  • 187.
    Andrae, Johan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Johansson, David
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Bursell, Martin
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Fakhrai, Reza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Jayasuriya, Jeevan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Manrique Carrera, Arturo
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    High-pressure catalytic combustion of gasified biomass in a hybrid combustor2005In: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 293, no 1-2, p. 129-136Article in journal (Refereed)
    Abstract [en]

    Catalytic combustion of synthetic gasified biomass was conducted in a high-pressure facility at pressures ranging from 5 to 16 bars. The catalytic combustor design considered was a hybrid monolith (400 cpsi, diameter 3.5 cm, length 3.6 cm and every other channel coated). The active phase consisted of 1 wt.% Pt/gamma-Al2O3 With wash coat loading of total monolith 15 wt.%. In the interpretation of the experiments, a twodimensional boundary layer model was applied successfully to model a single channel of the monolith. At constant inlet velocity to the monolith the combustion efficiency decreased with increasing pressure. A multi-step surface mechanism predicted that the flux of carbon dioxide and water from the surface increased with pressure. However, as the pressure (i.e. the Reynolds number) was increased, unreacted gas near the center of the channel penetrated significantly longer into the channel compared to lower pressures. For the conditions studied (lambda = 46, T-in = 218-257 degrees C and residence time similar to 5 ms), conversion of hydrogen and carbon monoxide were diffusion limited after ignition, while methane never ignited and was kinetically controlled. According to the kinetic model surface coverage of major species changed from CO, H and CO2 before ignition to O, OH, CO2 and free surface sites after ignition. The model predicted further that for constant mass flow combustion efficiency increased with pressure, and was more pronounced at lower pressures (2.5-10 bar) than at higher pressures (> 10 bar).

  • 188.
    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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  • 189.
    Andrinopoulos, Nikolaos
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Development of a test facility for experimental investigation of fluid-structure interaction2009Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Fluid-structure interaction phenomena are strongly related to the loading appearing on many energy converting components introducing limitations for improving their efficiency. The term “fluid-structure interaction” includes many phenomena with the “shock wave – boundary layer interaction” being one of the most important. This interaction is commonly met in turbomachines where the flow can accelerate enough to become compressible and can cause separation of the boundary layer formed on the structural components of the machine. This results to fluctuating loading on the structure which can lead to its failure due to High Cycle Fatigue (HCF).

    A vibrating structure in compressible flow can become unstable depending on the sign of the aerodynamic damping that the flow has on the structure. Although the mechanism that causes a structure to become unstable is known, the limits of the stability region are not yet possible to predict with reasonable accuracy. It is therefore necessary to investigate the underlying mechanism of fluid-structure interaction by means of experimental and numerical studies for providing prediction tools regarding the stability change.

    The present work aims at developing an experimental facility to be used for investigating fluid-structure interaction. The experimental setup is based on the concept of a simplified aeroelastic test case bringing into focus the area of interaction between an oscillating shock wave and a turbulent boundary layer. This work is based on previous research campaigns using the same generic experimental concept but takes the investigation further to higher and so far unexplored reduced frequencies. The experimental setup has been validated regarding its suitability to meet the research objectives by running vibration tests at an initial stage without the effect of flow.

    The results from the experimental validation of the facility have shown that the design objectives are met. Specifically the vibration response of the test object concerning vibration amplitude and vibration mode shape is desirable; the vibration amplitude is in the range of 0.5mm and the mode shape remains below the 2nd throughout the targeted frequency range (0-250Hz). This makes the facility suitable for simplified investigation of fluid-structure interaction, bringing the shock foot region into focus.

    Having validated the facility performing vibration tests without flow, tests with flow is the next step to take place. Since the vibration response of the test object has been investigated in detail, tests with flow will reveal the influence of fluidstructure interaction on the dynamic response of the test object. Similarly, the influence of this interaction on the flow side can be assessed by monitoring the flow parameters. As a first step for performing this investigation, the design study and the validation results for the experimental setup are presented in this work.

     

     

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  • 190.
    Andrinopoulos, Nikos
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Vogt, Damian
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Hu, Jiasen
    Fransson, Torsten H.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Design And Testing Of A Vibrating Test Object For Investigating Fluid-Structure Interaction2008In: PROCEEDINGS OF THE ASME TURBO EXPO 2008, VOL 5, PT A, NEW YORK: AMER SOC MECHANICAL ENGINEERS , 2008, p. 415-424Conference paper (Refereed)
    Abstract [en]

    In this study the vibration properties of a deforming test object are presented. The test object is bump shaped and is integrated into the wall of a transonic wind tunnel. The purpose for using such a test object is to study, in a generic manner, the unsteady aerodynamic phenomena occurring due to the presence of a vibrating structure in the flow. The setup is part of an ongoing study to address the phenomena of fluid-structure interaction and shock-boundary layer interaction. The design objective for the test object is to assimilate a IF vibration mode at a given section of atypical compressor blade. Finite element (FE) analyses have been used to predict the frequency response of the test object prior to manufacturing. The design objectives have been verified experimentally by time-resolved laser measurements. It has been found that the FE predictions are in good agreement with experimental data. Furthermore it has been shown that the present test object allows for the achievement of the targeted vibration properties up to a frequency of 250Hz, corresponding to a reduced frequency above 0.8.

  • 191.
    Andrén, Jacob
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Hodell, Anton
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Energilagring för företag i Finland2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Renewable energy sources such as wind are now well-established energy sources in many parts of the world. Large growth of unpredictable renewable energy generation that is dependent on weather makes energy storage an important component in the electrical system. During strong winds, a wind turbine may overproduce electricity. This means that the facility produces more electricity than can be sold on the electricity market. During other periods with large demand winds turbines might not be able to produce at all and electricity prices rise enormously as there is a shortage of electricity. The development of large-scale energy storage that can store energy when generation is greater than demand is therefore of great importance for the integration of many renewable energy sources. Energy storage currently used mainly at national level in order to take advantage of the energy that would otherwise go to waste.

    Because of the at times extreme volatility of electricity prices it could conceivably be profitable for end users such as companies and perhaps even individuals to use energy storage technologies. This would mean that the end user buys and stores energy when electricity is cheap and later use it when the price of electricity has risen and thereby make savings in money spent on electricity. Energy storage applied for end users is treated in this report.

    This is a project in sustainable energy technologies where the task is to investigate whether it is economically viable for end users in Finland to invest in and use an energy storage facility in order to save money. Energy storage with pumped hydro (PHES - Pumped Hydro Energy Storage) is identified as the most established and mature technology for large-scale intra-day energy storage. It is characterized by high efficiency and relatively low costs. Finland is considered to have the geographical requirements for the technology to be used.

     

    Possible electricity cost savings and investment costs are examined for various configurations of a PHES plants. The result shows that the variation in electricity prices in the Finnish electricity market in recent years have not been sufficient for the possible savings to cover the cost of the investment

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  • 192.
    ANDY, HANNA
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Arsalan, Ninos
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Living labs världen runt: En kartläggning av living labs i Sverige och världen2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Innovation is a central element for solving the world’s challenges of today, whether it is in the industry, the academia or the society. The concept living labs provides opportunities to accelerate and improve the innovation of today. This report aims to map some of the living labs in the world with the goal to identify success factors for the living lab that will be opened at the Royal Institute of Technology in Sweden, which is a ten year project.

    The literature study is divided into two parts, a general mapping of living labs and four case studies. The former deals with several living labs around the world and aims to show the differences in the concepts. The case studies consider four selected living labs in more detail with respect to the purpose, the methodology and the track record among others.

    The study establishes three main factors for success in a living lab; cross-sectional work as a collaboration model, cooperation and common goals among the key actors and continuous financial support.

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  • 193.
    Ang Co, Alberto
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Energy-Efficient Homes Using Off-The-Shelf Products and Materials2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Canada is a highly energy-intensive country, because of its high living standard, large territory, extreme cold climate, and significant industrial base. In 2011, Canada’s residential sector consumed about 1,446 petajoules (PJ), accounting for 13.5 percent of the total energy use and offering significant energy-saving potential. The key objective of this thesis project is to quantify the potentially achievable improvement in energy efficiency of a typical single detached home in a municipality in Ontario, Canada by using off-the-shelf products and materials. A building simulation tool modeled the energy use of a prototypical house using eQUEST, a DOE-2 based program that calculates the energy use and cost of commercial or residential building given information on weather, architectural, envelope materials, internal loads, electrical, mechanical, schedules, and economic parameters. Simulation results show that 36.8 percent energy savings are attainable by using off-the-shelf products and materials for building envelope, lighting, electrical appliances, and heating, ventilation, and air conditioning (HVAC) system and control; these exclude heat pumps, which may not be economical to use as the only heat source in cold climates. However, recent developments in heat pump technologies and relatively low electricity prices in certain locations in Canada offer major opportunity to save energy by up to 54.2 percent through the use of heat pumps.

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  • 194.
    Angalev, Mikhail
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Energy saving at gas compressor stations through the use of parametric diagnostics2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Increasingly growing consumption of natural gas all around the world requires development of new transporting equipment and optimization of existing pipelines and gas pumping facilities. As a special case, Russian gas pumping system has the longest pipes with large diameter, which carry great amounts of natural gas. So, as reconstruction and modernization needs large investments, a need of more effective and low cost tool appeared. As a result diagnostics became the most wide-spread method for lifecycle assessment, and lifecycle extension for gas pumping units and pipelines.One of the most effective method for diagnostics of gas pumping units is parametric diagnostics. It is based on evaluation of measurement of several termo-gas dynamic parameters of gas pumping units, such as pressures, temperatures and rotational speed of turbines and compressors.In my work I developed and examined a special case of parametric diagnostics – methodic for evaluation of technical state and output parameters for gas pumping unit “Ural-16”. My work contains detailed analysis of various defects, classified by different GPU’s systems. The results of this analysis are later used in development of the methodic for calculation of output parameters for gas pumping unit.GPU is an extremely complex object for diagnostics. Around 200 combinations of Gas Turbine engines with centrifugal superchargers, different operational conditions and other aspects require development of separate methodic almost for each gas pumping unit type.Development of each methodic is a complex work which requires gathering of all possible parametric and statistical data for the examined gas pumping unit. Also parameters of compressed gas are measured. Thus as a result a number of equations are formed which finally allow to calculate such parameters as efficiency, fuel gas consumption and technical state coefficient which couldn’t be measured directly by existing measuring equipment installed on the gas compressor station.

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    Energy saving at gas compressor stations through the use of parametric diagnostics
  • 195.
    Anghel, Ionut
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Technology.
    Anglart, Henryk
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Technology.
    Hedberg, Stellan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Experimental investigation of post-dryout heat transfer in annuli with flow obstacles2012In: Nuclear Engineering and Design, ISSN 0029-5493, E-ISSN 1872-759X, Vol. 246, p. 82-90Article in journal (Refereed)
    Abstract [en]

    An experimental study on post-dryout heat transfer was conducted in the High-pressure WAter Test (HWAT) loop at the Royal Institute of Technology in Stockholm, Sweden. The objective of the experiments was to investigate the influence of flow obstacles on the post-dryout heat transfer. The investigated operational conditions include mass flux equal to 500 kg/m2 s, inlet sub-cooling 10 K and system pressure 5 and 7 MPa. The experiments were performed in annuli in which the central rod was supported with five pin spacers. Two additional types of flow obstacles were placed in the exit part of the test section: a cylinder supported on the central rod only and a typical BWR grid spacer cell. The measurements indicate that flow obstacles improve heat transfer in the boiling channel. It has been observed that the dryout power is higher when additional obstacles are present. In addition the wall temperature in post-dryout heat transfer regime is reduced due to increased turbulence and drop deposition. The present data can be used for validation of computational models of post-dryout heat transfer in channels with flow obstacles.

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    Experimental investigation of post-dryout heat transfer in annuli with flow obstacles
  • 196.
    Anglart, Henryk
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. KTH, School of Engineering Sciences (SCI), Physics, Nuclear Engineering.
    CFD modelling of annular two-phase flow and heat transfer2017In: 17th International Topical Meeting on Nuclear Reactor Thermal Hydraulics, NURETH 2017, Association for Computing Machinery, Inc , 2017Conference paper (Refereed)
    Abstract [en]

    This paper describes the governing phenomena and current approaches in their modeling for annular two-phase flow and heat transfer. The complexity of the flow, including liquid film, disturbance waves, turbulent gas core, droplet deposition and entrainment, are discussed. Computational Fluid Dynamics (CFD) approach to model the phenomena is presented. 

  • 197.
    Anglart, Henryk
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Thermal safety margins in nuclear reactors2024Book (Other academic)
    Abstract [en]

    This book presents an overview of state-of-the-art approaches to determine thermal safety margins in nuclear reactors. It presents both the deterministic aspects of thermal safety margins of nuclear reactors and a comprehensive treatment of aleatory and epistemic uncertainties to facilitate the understanding of these two difficult topics at various academic levels, from undergraduates to researchers in nuclear engineering. It first sets out the theoretical background before exploring how to determine thermal safety margins in nuclear reactors, through examples, problems and advanced state-of-the-art approaches. This will help undergraduate students better understand the most fundamental aspects of nuclear reactor safety. For researchers and practitioners, this book provides a comprehensive overview of the most recent achievements in the field, offering an excellent starting point to develop new methods for the assessment of the thermal safety margins. This book is written to bridge the gap between deterministic methods and appropriate treatment of uncertainties to assess safety margins in nuclear reactors, presenting these approaches as complementary to each other. Even though these two approaches are frequently used in parallel in real-world applications, there has been a lack of a consistent teaching approach in this area. This book is suitable for readers with a background in calculus, thermodynamics, fluid mechanics, and heat transfer. It is assumed that readers have previous exposure to such concepts as laws of thermodynamics, enthalpy, entropy, and conservation equations used in fluid mechanics and heat transfer. Key Features: • Covers the theory, principles, and assessment methods of thermal safety margins in nuclear reactors whilst presenting state-of-the-art technology in the field • Combines the deterministic thermal safety considerations with a comprehensive treatment of uncertainties, offering a framework that is applicable to all current and future commercial nuclear reactor types • Provides numerous examples and problems to be solved.

  • 198.
    Anglart, Henryk
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Technology.
    Persson, Per
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Technology.
    Hedberg, Stellan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    EXPERIMENTAL INVESTIGATION OF STATIONARY AND TRANSIENT POST-DRYOUT HEAT TRANSFER IN 22.1X10 MM ANNULUS WITH SPACERS2005In: Proceedings of the Eleventh International Topical Meeting on Nuclear Reactor Thermal-Hydraulics, 2005Conference paper (Refereed)
    Abstract [en]

    Experimental investigation of the post-dryout heat transfer in annulus test section has been performed in the high-pressure two-phase loop at the Royal Institute of Technology (KTH). The test section has an annular geometry with 10 mm rod outer diameter and 22.1 mm tube inner diameter. Seven spacers are located along the test section to keep the rod and the tube equidistant along the test section. Both the tube and the rod are manufactured of Inconel 600 to withstand high temperatures. Several thermocouples have been installed on the tube and the rod surface to measure the local temperature.The measurements have been performed for a wide range of the inlet mass flow rate, keeping the inlet subcooling equal to 10 K and the pressure to 70 bars. Uniform axial power distributions have been applied on the rod and tube walls, however, several different ratios between the heat fluxes on the two surfaces have been applied. Both steady-state and transient measurements have been performed in which axial distribution of wall temperatures have been registered.The experiments indicate a very strong influence of spacers on post-dryout heat transfer. In particular, for several cases with relatively low local quality the dryout spot is limited to a direct proximity of spacers, stretching from approximately 10 cm upstream of the spacer to 5 cm downstream of the spacer. Only for relatively high powers the dryout patch could cover the whole distance between two neighboring spacers.

  • 199. Anjo, J.
    et al.
    Neves, D.
    Silva, C.
    Shivakumar, Abhishek
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Howells, Mark I.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Modeling the long-term impact of demand response in energy planning: The Portuguese electric system case study2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 165, p. 456-468Article in journal (Refereed)
    Abstract [en]

    With the urge to decrease carbon emissions, electricity systems need to evolve to promote the integration of renewable resources and end-use energy efficiency. Demand Response (DR) can be used as a strategy, one among many, to improve the balance between demand and supply of electricity, especially in systems that rely heavily on variable energy renewable resources. Thus, it is important to understand up to what extent a countrywide system would cope with DR implementation. In this work, the impact of demand response in the long-term is assessed, using a model of the Portuguese electricity system in the modeling tool OSeMOSYS. The theoretical potential of DR is computed to understand better the impact on the overall system planning, by analyzing three scenarios – a business as usual scenario, a carbon-free system scenario in 2050, and a scenario without heavy carbon emission restrictions. DR impact in all three scenarios results in a decrease in the overall costs, on the capacity installed and in an increase in the percentage of renewable capacity. Further, an economic analysis showed that DR would take 15 years, on average, to influence the average electricity cost and that the reduction in total costs is mainly due to the avoided capacity investments. 

  • 200.
    Anlaue, Saide
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Chicala, Salomao
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Design and Simulation of a PV and SDHW Systems using TRNSYS for Graphit Kropfmühl Aktien Gesellschaft Training School in Ancuabe2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Mozambique is a country with some problems concerning the interconnection of electric grid and lack of local distributor of fossil fuels like GPL, gasoline and diesel in many districts. Due to the lack of fuel distributors the price of mentioned fossil fuels increases when moving away from the main three harbors (Nacala, Beira and Maputo) to the inland and many roads are not in good condition for driving fuel trucks. Even in districts where are already connected to the national electric grid it is often observed cut off due to different kind of problems such as obsolete infrastructure, stealing of electric components and lack of alternative (back up) electric grid and resource.The aim of the present project is to design and simulate a stand-alone photovoltaic system and a solar water heating system for a projected training school in Ancuabe district at the Northern Province of Cabo Delgado. The school project is owned by a Germany mining company called Graphit Kropfmühl AG with graphite exploitation concession in Mozambique. These systems were simulated using TRNSYS software, a transient simulation program.In the modeling of those systems in TRNSYS all required components where represented by different Types. The results for the photovoltaic system were optimized in such way that the total power consumption comes totally from the system. So to fulfill this goal it was important to monitor the simulation indicator of power coming from grid in order to reduce to zero, without increasing the batteries capacity. Due to this a considerable dumped power were observed and it can be directed to the workshop during the day for the light and low power appliances. Dumped power is the power which is produced and is not used by the system, in other hand the power from grid is the power that the user has to pay from available electricity grid around or it is the power that is not covered by the installed photovoltaic system.In other hand for the solar water heating system it was optimized so that throughout the year the load hot water temperature during the shower time in dormitory is between 39-40oC as recommended and at the same time the system is designed to work without an auxiliary heating to avoid extra cost with other kind of energy for the auxiliary heater.The goal of the systems optimization with TRNSYS is to have best gains without increasing the system and consequently reducing the high initial investment cost.

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