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  • 1.
    Abadi, Imam
    et al.
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Hardiana, Tiara Oktavia
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Imron, Chairul
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Fitriyanah, Dwi Nur
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Jani, Yahya
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Abdullah, Kamaruddin
    Darma Persada University, Indonesia.
    Design of Adaptive Neuro-Fuzzy Inference Control Based One-Axis Solar Tracker on Battery Charging System2020In: E3S Web of Conferences, EDP Sciences, 2020, Vol. 190, p. 1-15, article id 00015Conference paper (Refereed)
    Abstract [en]

    The photovoltaic (PV) panel can produce electrical energy that is very environmentally friendly and easy to use. The use of PV panels is suitable for supplying peak loads or at night using batteries as energy storage. However, the battery needs to manage for control, and the battery can last long. The solution to battery management problems is through research about the battery charging system. The DC-DC converter used is the Single Ended Primary Inductance Converter (SEPIC) type. Voltage Control of the battery charging using Adaptive Neuro-Fuzzy Inference System (ANFIS). In the simulation of bright conditions, ANFIS controls can track the charging point set point and obtain a voltage response with a rise time of 0.0028 s, a maximum overshoot of 0.027 %, a peak time of 0.008 s, and a settling time of 0.0193 s. When charging a solar tracker, PV battery gets a 0.25 % increase compared to a fixed PV panel. PV solar tracker can follow the direction of the sun's position. The irradiation value and maximum temperature affect the input voltage and input current that enters the converter. © The Authors, published by EDP Sciences, 2020.

  • 2.
    Abadi, Imam
    et al.
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Uyuniyah, Qurrotul
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Fitriyanah, Dwi Nur
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Jani, Yahya
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Abdullah, Kamaruddin
    Darma Persada University, Indonesia.
    Performance Study of Maximum Power Point Tracking (MPPT) Based on Type-2 Fuzzy Logic Controller on Active Dual Axis Solar Tracker2020In: E3S Web of Conferences, EDP Sciences, 2020, Vol. 190, p. 1-16, article id 00016Conference paper (Refereed)
    Abstract [en]

    World energy consumption increases with time, so that occur an energy imbalance. Many breakthroughs have developed to utilize renewable energy. The photovoltaic system is one of the easy-to-use renewable energies. The power conversion from PV fixed is still low, so the PV system is designed using the active dual-axis solar tracker. The PV tracker position can be adjusted to change the sun position to get maximum efficiency. The active dual-axis solar tracker system is integrated with the maximum power point tracking (MPPT) algorithm to keep PV operating at a maximum power point even though input variations change. The active dual-axis solar tracker system integrated with the maximum power point tracking (MPPT) algorithm to keep PV operating at a maximum power point even though input variations change. Tracking test simulation had done by comparing the output power of a fixed PV system with the active dual-axis solar tracker. Type-2 fuzzy logic based MPPT successfully increased the average output power by 10.48 % with the highest increase of 17.48 % obtained at 15:00 West Indonesia Time (GMT+7). The difference in power from a fixed PV system with the active dual-axis solar tracker of 36.08 W is from the output power worth 206.3 to 242.4 W. © The Authors, published by EDP Sciences, 2020.

  • 3.
    Adam, Stenlund
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    John, Barnekow
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Energieffektivisering av Ronneby is-arena samt vädrets termodynamiska påverkan2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Today Sweden has 341 ice hockey arenas, around 140 outdoor ice hockey rinks, 60 ice fields for bandy and about 35 curling arenas. In addition, the numbers of indoor bandy arenas are increasing. The cooling systems installed today should be able to lower its energy consumption with 10-30%.In this thesis, Ronneby ice-arena has been researched. This artificial cooling facility was inaugurated 2011 and is one of the newest in Sweden. This is an outdoor ice field for bandy and therefor has no roof or walls to cover the field. Ronneby ice-arena has problems with uneven cooling distribution of the ice field. This results in cracks and uneven ice quality. These problems also result in higher energy consumption than necessary.To find a solution for the uneven cooling of the ice field flow measurements were carried out in the brine circuit. To get a better understanding of the cooling distribution, temperature measurements were carried out on the brine feeding lines. A calculation has been performed on what energy savings a speed control of the brine circulation pumps depending on the outdoor temperature could generate. Another calculation was made to see the possible savings with a windshield around the field. In this thesis the benefits of a heat recovery system on the cooling compressors refrigerant has been investigated. The heat recovery system could heat the locker rooms, the clubhouse, the showers and the hot water for the Zambonis.In order to perform the necessary calculation for this thesis, Fredriksbergs BK and Ronneby municipality provided operating data.The actions proposed to Ronneby ice-arena to solve the uneven cooling of the ice field is to change the location of the brine feeding line connection point. At the same time this work is carried out it’s suggested that the brine feed and return lines get insulated. When the uneven cooling problems have been solved, a speed control system should be installed to control the brine circulation pumps, in order to lower the electricity consumption. Ronneby ice-arena has the possibility to install a heat recovery system. Therefore it is suggested to install a heat exchanger on each cooling compressor refrigerant. This installation is to be used to heat the clubhouse, the showers and the hot water for the Zambonis. The system to cool the condensers with seawater and currently the heat pump are not optimal designed. The installed heat pump does not work when the seawater temperature is below 5°C, therefore the system should be redesigned.

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  • 4.
    Ahlgren, Fredrik
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Reducing ships' fuel consumption and emissions by learning from data2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the context of reducing both greenhouse gases and hazardous emissions, the shipping sector faces a major challenge as it is currently responsible for 11% of the transport sector’s anthropogenic greenhouse gas emissions. Even as emissions reductions are needed, the demand for the transport sector rises exponentially every year. This thesis aims to investigate the potential to use ships’ existing internal energy systems more efficiently. The thesis focusses on making existing ships in real operating conditions more efficient based logged machinery data. This dissertation presents results that can make ship more energy efficient by utilising waste heat recovery and machine learning tools. A significant part of this thesis is based on data from a cruise ship in the Baltic Sea, and an extensive analysis of the ship’s internal energy system was made from over a year’s worth of data. The analysis included an exergy analysis, which also considers the usability of each energy flow. In three studies, the feasibility of using the waste heat from the engines was investigated, and the results indicate that significant measures can be undertaken with organic Rankine cycle devices. The organic Rankine cycle was simulated with data from the ship operations and optimised for off-design conditions, both regarding system design and organic fluid selection. The analysis demonstrates that there are considerable differences between the real operation of a ship and what it was initially designed for. In addition, a large two-stroke marine diesel was integrated into a simulation with an organic Rankine cycle, resulting in an energy efficiency improvement of 5%. This thesis also presents new methods of employing machine learning to predict energy consumption. Machine learning algorithms are readily available and free to use, and by using only a small subset of data points from the engines and existing fuel flow meters, the fuel consumption could be predicted with good accuracy. These results demonstrate a potential to improve operational efficiency without installing additional fuel meters. The thesis presents results concerning how data from ships can be used to further analyse and improve their efficiency, by using both add-on technologies for waste heat recovery and machine learning applications.

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  • 5.
    Ahlgren, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Mondejar, Maria E.
    Technical University of Denmark, Denmark.
    Thern, Marcus
    Lund University, Sweden.
    Predicting dynamic fuel oil consumption on ships with automated machine learning2019In: Innovative Solutions for Energy Transitions: Proceedings of the 10th International Conference on Applied Energy (ICAE2018) / [ed] Prof. J.Yanab, Prof. H.Yang, cDr. H.Lid, Dr. X.Chene, Elsevier, 2019, Vol. 158, p. 6126-6131Conference paper (Refereed)
    Abstract [en]

    This study demonstrates a method for predicting the dynamic fuel consumption on board ships using automated machine learning algorithms, fed only with data for larger time intervals from 12 hours up to 96 hours. The machine learning algorithm trained on dynamic data from shorter time intervals of the engine features together with longer time interval data for the fuel consumption. To give the operator and ship owner real-time energy efficiency statistics, it is essential to be able to predict the dynamic fuel oil consumption. The conventional approach to getting these data is by installing additional mass flow meters, but these come with added cost and complexity. In this study, we propose a machine learning approach using auto machine learning optimisation, with already available data from the machinery logging system.

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  • 6.
    Ahlgren, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Thern, Marcus
    Lund university, Sweden.
    Auto Machine Learning for predicting Ship Fuel Consumption2018In: Proceedings of ECOS 2018 - the 31st International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Guimarães, 2018Conference paper (Refereed)
    Abstract [en]

    In recent years, machine learning has evolved in a fast pace as both algorithms and computing power are constantly improving. In this study, a machine learning model for predicting the fuel oil consumption from engine data has been developed for a cruise ship operating in the Baltic Sea. The cruise ship is equipped with legacy volume flow meters and newly installed mass flow meters, as well as an extensive set of logged time series data from the machinery logging system. The model is developed using state-of-the-art Auto Machine Learning tools, which optimises both the model hyper parameters and the model selection by using genetic algorithms. To further increase the model accuracy, a pipeline of different models and pre-processing algorithms is evaluated. An extensive model trained for a certain system can be used for optimisation simulation, as well as online energy efficiency prediction. As the models automatically adapt to noisy sensor data and thus function as a watermark of the machinery system, these algorithms show a potential in predicting ship energy efficiency without installation of additional mass flow meters. All tools used in this study are Open Source tools written in Python and can be applied on board. The study shows great potential for utilising large amounts of already available sensor data for improving the accuracy of the predicted ship energy consumption.

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  • 7.
    Ahlgren, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Thern, Marcus
    Lund University, Sweden.
    Genrup, Magnus
    Lund University, Sweden.
    Mondejar, Maria E.
    Technical University of Denmark, Denmark.
    Energy integration of organic rankine cycle, exhaust gas recirculation and scrubber2018In: Trends and challenges in maritime energy management / [ed] Aykut I. Ölçer, Momoko Kitada, Dimitrios Dalaklis & Fabio Ballini, Cham, Switzerland: Springer, 2018, p. 157-168Chapter in book (Refereed)
    Abstract [en]

    The vast majority of ships trafficking the oceans are fuelled by residual oil with high content of sulphur, which produces sulphur oxides (SOx) when combusted. Additionally, the high pressures and temperatures in modern diesel engines also produce nitrogen oxides (NOx). These emissions are both a hazard to health and the local environment, and regulations enforced by the International Maritime Organization (IMO) are driving the maritime sector towards the use of either distillate fuels containing less sulphur, or the use of exhaust gas cleaning devices.TwocommontechniquesforremovingSOx andlimitingNOx aretheopen loop wet scrubber and exhaust gas recirculation (EGR). A scrubber and EGR installation reduces the overall efficiency of the system as it needs significant pumping power, which means that the exhaust gases are cleaner but at the expense of higher CO2 emissions. In this paper we propose a method to integrate an exhaust gas cleaning device for both NOx and SOx with an organic Rankine cycle for waste heat recovery, thereby enhancing the system efficiency. We investigate three ORC configurations, integrated with the energy flows from both an existing state-of-the-art EGR system and an additional open loop wet scrubber.

  • 8.
    Ahlin, Kristofer
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Absorptionskylmaskiner ombord: En undersökning om absorptionsprocessens potential ombord fartyg2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med denna undersökning är att teoretiskt undersöka den vatten/litiumbromidbaserade absorptionsprocessens potential ombord fartyg då processen enbart drivs av huvudmaskinens högtemperaturkylvatten. Undersökningen genomförs teoretiskt mot tre olika fartyg samt Sjöfartshögskolan i Kalmars maskinrumssimulator. För vardera fartyg undersöks driftenergikällan och kylbehovet ombord. Med det som underlag dras en slutsats om den vatten/ litiumbromidbaserade absorptionsprocessens potential ombord fartyget. Fartygens resultat ligger till grund för slutsatsen. Undersökningen visade att det finns potential för tekniken ombord undersökta fartyg.

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  • 9.
    Ahmad, Waqar
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Coke-free conversion of benzene at high temperatures2023In: Journal of the Energy Institute, ISSN 1743-9671, E-ISSN 1746-0220, Vol. 109, article id 101307Article in journal (Refereed)
    Abstract [en]

    This study investigates the conversion of benzene in a novel highly non-porous ɣ-Al2O3 packed bed reactor at 1000–1100 °C. The influences of packed bed presence, reforming medium (steam and CO2), gas flow rate and benzene concentration on steady state benzene conversion are examined. In presence of packed bed, benzene conversions of 52, 75, and 84% were achieved with combined steam and CO2 reforming at 1000, 1050, and 1100 °C, respectively. Whereas, benzene conversion of 65% without the packed bed at 1000 °C experienced a continuous increase in differential upstream pressure (DUP) of high temperature (HT) filter at reactor downstream due to deposition of in situ generated coke. High concentrations of generated CO and H2 of 2.3 and 6 vol% with packed bed than 1.4 and 4.7 vol% without the packed respectively, were achieved. CO2 reforming achieved high benzene conversions of 68–98% than 42–80% achieved with stream reforming at packed bed reactor temperatures of 1000–1100 °C. The results indicated that presence of ɣ-Al2O3 packed bed with possible surface reactions directed the conversion of benzene to combustible gases instead of coke. Hence, ɣ-Al2O3 packed bed reactor could be a suitable choice for coke-free conversion of tar of gasifier producer gas.

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  • 10.
    Ahmad, Waqar
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Investigation of different configurations of alumina packed bed reactor for coke free conversion of benzene2024In: Chemical engineering research & design, ISSN 0263-8762, E-ISSN 1744-3563, Vol. 201, p. 433-445Article in journal (Refereed)
    Abstract [en]

    Conversion of producer gas tar without coke generation is a great challenge. This study investigates conversion of tar model benzene using different configurations of highly non-porous ɣ-Al2O3 packed bed reactor at 1000–1100 0C. The configurations comprised of different positions (relative to top (P1), center (P2) and bottom (P3) of reactor furnace), heights (5, 13 and 25 cm) and particles sizes (0.5, 3 and 5 mm) of alumina packed bed. Steam and CO2 were used as reforming media for tested benzene concentrations (0.4–1.8 vol%). The results showed benzene conversions of 48–91% with negligible steady thin coke generation using a packed bed (height: 25 cm, particles size: 3 mm) at P1. Whereas, relative high benzene conversions of 63–93 and 68–95% at P2 and P3 respectively with unsteady thick coke generation at benzene concentrations greater than 0.4 vol% increased differential upstream pressures (DUPs) of beds. Similar unsteady coke generation at benzene concentrations greater than 0.8 vol% and temperature of 1100 0C was observed with packed beds of heights of 5 and 13 cm, and particles size of 0.5 mm at P1. Generation of unsteady coke with condensed structure as evidenced by its characterization was attributable to increased benzene polymerization and reduced bed surface gasification reactions due to improperly installed packed bed. Developed kinetic model predicted well the generated coke. As conclusion, properly installed alumina packed bed pertaining to tar concentration and other experimental conditions may inhibit coke generation during tar conversion.

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  • 11.
    Ahmad, Waqar
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Sultan Qaboos Univ, Oman.
    Vakilinejad, Ali
    Sultan Qaboos Univ, Oman;Univ Tehran, Iran.
    Aman, Zachary M.
    Univ Western Australia, Australia.
    Vakili-Nezhaad, G. Reza
    Sultan Qaboos Univ, Oman.
    Thermophysical Study of Binary Systems of tert-Amyl Methyl Ether with n-Hexane and m-Xylene2019In: Journal of Chemical and Engineering Data, ISSN 0021-9568, E-ISSN 1520-5134, Vol. 64, no 2, p. 459-470Article in journal (Refereed)
    Abstract [en]

    This work presents the experimentally determined density (rho), viscosity (eta), speed of sound (u), and surface tension (sigma) data for tert-amyl methyl ether (TAME) + n-hexane and TAME + m-xylene systems at several temperatures (298.15, 308.15, 318.15, 323.15, and 328.15 K). These experimentally determined thermophysical data are utilized to compute various excess/deviation parameters such as molar volume (V-E), isentropic compressibility (K-s(E)), speed of sound (u(E)), deviation in viscosity (Delta In eta), isobaric thermal expansion coefficient (alpha(E)(P)), and surface tension (sigma(E)). The inspection of parameters response may interpret the existing specific molecular interactions as well as the mixing behavior of solutions. The critical analysis of observed parametric behavior have unveiled the strong and weak molecular interactions in TAME with m-xylene and TAME with n-hexane systems, respectively.

  • 12.
    Alajbegovic, Faruk
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Imsirovic, Alen
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Uppföljning av energiprestanda samt boendes upplevelser av Portvakten Söder: Energy Monitoring and residents' perceptions of Portvakten Söder2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Portvakten Söder i Växjö, med sina två huskroppar och 64 lägenheter är de högsta passivhusen i Sverige med en trästomme. En energiuppföljning görs för år 2012. Skillnader kring projekterat och uppmätt värde behandlas och klargörs. Granskning av funktionalitet och värmeåtervinningsmängd av avloppsvärmeväxlaren utreds. Ett frågeformulär har skickats ut och sammanställts, där hyresgästerna delar med sig av sina upplevelser utav Portvakten Söder.

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  • 13. Albertazz, S.
    et al.
    Basile, F.
    Brandin, Jan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Einvall, Jessica
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Fornasar, G.
    Hulteberg, C.
    Sanati, M.
    Trifir, F.
    Vaccari, A.
    Pt/Rh/MgAl(O) Catalyst for the Upgrading of Biomass-Generated synthesis gases.2009In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 23, no 1, p. 573-579Article in journal (Refereed)
  • 14. Albertazzi, Simone
    et al.
    Basile, Francesco
    Barbera, Davide
    Benito, Patricia
    Brandin, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Einvall, Jessica
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Fornasari, Giuseppe
    Trifirò, Ferruccio
    Vaccari, Angelo
    Deactivation of a Ni-Based Reforming Catalyst During the Upgrading of the Producer Gas, from Simulated to Real Conditions2011In: Topics in catalysis, ISSN 1022-5528, E-ISSN 1572-9028, Vol. 54, no 10, p. 746-754Article in journal (Refereed)
    Abstract [en]

    The deactivation of a nickel reforming catalyst during the upgrading of the producer gas obtained by gasification of lignocellulosic biomass was studied. The research involved several steps: the selective deactivation of the catalyst in a laboratory scale; the streaming of the catalyst with the producer gas of a downdraft and an oxygen/steam circulating fluidized bed (CFB) gasifier; and tests in a reformer placed in a slipstream of the CFB gasifier. The information obtained allowed to elucidate the catalyst deactivation mechanisms taking place during the reforming of the producer gas: physical deactivation by deposition of fine ashes, aerosol particulate or carbon; poisoning by H2S and HCl present in the gas phase and thermal sintering because of the high operation temperatures required to avoid the chemical deactivation. These physical and chemical effects depended on the composition of the biomass fuel.

  • 15.
    Alegrim, Georg
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Anaje, Alexander
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Värmeåtervinning av luft i kycklingstallar: Återanvändning av energin i frånluften för luftförvärmning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The consumption of chicken per inhabitant have increased in Sweden the last couple of years and today 23,2 kg is consumed per inhabitant and year. Because of this rise of Swedish chicken consumption, the awareness of investing in climate-smart alternatives have increased by the companies. The companies are decreasing the energy required during production, which ultimately leads to a reduced heating cost.

    The animal stall is heated by a boiler where water-based heating elements are providing the animal stall with heat along the walls. 

    It has been considered problematic to heat up the animal stall by reintroducing the air from inside the stall due to the fact that this air often is too dusty, which contributes to blockage of filters and ducts. There are a number of different heat exchangers that can handle this kind of dust and particles today. 

    Two different heat exchangers will be compared, a recuperative plate heat exchanger and a regenerative rotary heat exchanger.

    The animal stall must keep a low CO2 value and it is important to keep the chickens bedding dry by a low humidity inside the stall.

    The study shows that the total heat for one breeding round, which today is approximately 48,2MWh, which equals a saving by using an air heat exchanger of 24,8MWh. The result of the comparison of the two heat exchangers has shown that the regenerative (rotary) heat exchanger reintroduces moisture in the stall, which the recuperative (plate heat exchanger) does not. The follow up for this study was 34 days, from the chickens’ birth to the slaughter. During day 28-30 the animal stall becomes self-sufficient considering heat, which means that the heat exchanger could generate the heat required for the facility without the use of the stalls chip boiler.

    The study is implemented with a calculated volume flow due to a short outlet channel on the system, this can lead to a risk of a minor faulty value.

    Regard to the humidity in the stall, it is preferable to use a plate heat exchanger as the rotating heat exchanger precipitates water of 3 grams/kg of dry air.

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  • 16.
    Ali, Ahmed
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Dynamic modelling of electricity arbitrage for single-family homes: Assessing the cost-effectiveness of implementing Energy Storage and Demand-Side Load Management.2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the context of electricity, arbitrage trading involves taking advantage of existing price variations within electricity markets. The report conducted financial modelling for energy storage systems and demand-side load management for electricity arbitrage trading in single-family homes. The analysis included two different energy storage systems: a thermal energy storage system and a battery energy storage system. Additionally, electricity spot cost reduction was compared between electricity arbitrage trading and traditional energy efficiency measures such as air-to-water and ground-source heat pumps.

    The report's findings indicated that air-to-water and ground-source heat pumps emerged as the most economically viable choices for reducing electricity spot costs, irrespective of the studied electricity price area. The thermal energy storage system, employing an insulated hot water storage tank, ranked the third most efficient in achieving cost savings. The battery energy storage system, represented by a lithium home battery system, demonstrated the lowest rate of cost saving among the analyzed energy efficiency measures. 

    The financial modelling highlighted the economic potential for thermal energy storage systems, particularly in southern Sweden's electricity price areas SE3 and SE4. On the other hand, no economically viable options for battery energy storage systems were identified, regardless of the studied electricity price area. As a results, the report recommends utilizing thermal energy storage systems and implementing demand-side load management as strategies to hedge against future electricity price volatility.

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  • 17.
    Alm, Alexander
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Kolkraft med CSS2012Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    ABSTRAKT

    Detta arbete om kolkraft med CCS syftar till att ge läsaren en lite djupare bild av hur avskiljning, transportering och lagring kan fungera vid ett koleldat kraftverk utrustat med koldioxidavskiljning.

    Vilka olika tekniska metoder som finns eller är under utveckling för de olika stegen i processen och hur dessa fungerar.

    Arbetet tar även upp historien bakom kolet som bränsle och hur utvecklingen av olika reningstekniker tog fart.

    Generella fördelar och nackdelar med CCS bollas fram o tillbaka miljömässiga aspekter med tekniken samt den ekonomiska lönsamheten undersöks.

    Arbetet avslutas med en överblick över en verklig pilotanläggning i Schwarzepumpe i Tyskland.

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  • 18.
    Almert, Josef
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Ljung, David
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Frekvensomriktardrift av sjökylvattenpumpar: Ett underlag för konvertering från strypreglering2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been conducted in cooperation with the engine crew onboard theSwedish Maritime Administration's icebreakers. The purpose of this work is to highlightthe benefits of conversion from throttling control to frequency control, of the sea waterpumps on their icebreakers. This by means of a frequency converter.Energy efficiency is something that is prioritized on modern ships, where everything isbuilt and optimized to be as cost-effective as possible. Old ships do often have oldersystems that are inefficient from an energy point of view, as the technology at the timeof construction was limited. Today's technology is getting cheaper and cheaper, whichmakes more people willing to phase out the old inefficient systems with throttleregulation, against new frequency-controlled systems.The result was that after three to four years, it would be worth installing a drive. Thefuel costs for running two cooling water pumps with a 60% load drive will generate asaving of 16961 SEK in fuel consumption. Running the sea water pumps withfrequency drives will help reduce wear and tear on pump and pipe systems, it will alsogenerate a reduced CO2 emission, which is beneficial from an environmental point ofview.The conclusion was that it was profitable to install frequency converters, both from anenvironmental and cost point of view.

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  • 19.
    Alriksson, Stina
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Grip, Carl-Erik
    Luleå Tekniska Universitet.
    Studies of preferences as an extra dimension in system studies2011In: World Renewable Energy Congress – Sweden, 8–13 May, 2011Linköping, Sweden: Volume 7, Industrial Energy Efficiency / [ed] Bahram Moshfegh, Linköping: Linköping University Electronic Press, 2011, p. 1732-1739Conference paper (Refereed)
    Abstract [en]

    Industrial energy systems are complicated networks where changes in one process influence itsneighboring processes. The network complexity increases if production/use of bio fuel is introduced in anexisting system. Process integration can be a useful tool to study such systems and thus avoid sub optimization.However, changes in an industrial complex do not only influence the technical values of energy and materialefficiency. The social impact is also important and sometimes is comparable to that of technical factors.A process integration project has recently been carried out for a paper mill in northern Sweden with a side viewon future expansion with a bio refinery. An activity to study the social impacts were included through a Conjointanalysis, a stated preference method that combines statistics and interviewing technique.The results indicate that the participants are divided in four groups, the largest group focusing on a change in theprocess towards a bio refinery, the second largest focusing on the local environment. The third and fourth groupboth look at the local forestry, one group wanting to increase local forest production, and one rejecting anincrease.

  • 20.
    Alsabouni, Mohammad Mulham
    et al.
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Okpalanwaka, Vitalis Chika
    Utilization of energy storage to improve energy efficiencyand power quality: Case study – Holtab AB factory2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    Utilization of Energy Storage to Improve Energy Efficiency and Power Quality
  • 21.
    Alsyouf, Imad
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Wind energy system reliability and maintainability, and operation and maintenance strategies2010In: Wind energy systems: optimising design and construction for safe and reliable operation, Cambridge: Woodhead Publishing Limited, 2010, no 10, p. 303-328Chapter in book (Refereed)
    Abstract [en]

    This chapter discusses the reliability, operation and maintenance strategies for wind power systems. It examines the role of systems engineering in optimising the aspects of a system relating to reliability, supportability and maintainability. It considers various maintenance approaches and the role of proper maintenance practices in providing a secure and reliable energy supply at the right cost. It discusses the importance of identifying and understanding the relevant cost factors associated with wind power systems, based on lifecycle costing and using relevant performance measures to help select a cost-effective maintenance approach. It then reviews some efforts aimed at improving the design, production, construction, operation and maintenance of wind power systems. Finally, some future trends are discussed in the areas of operation and maintenance of wind power systems.

  • 22.
    Alvarsson, Johan
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Sjöström, Victor
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Konvertering av Kraftringens geotermianläggning: Undersökning av alternativ till köldmediet R134a2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the geothermal plant of 'Kraftringen' the refrigerant R134a, which is a fluorescent greenhouse gas with relatively high GWP (Global Warming Potential), circulates. When the new F-Gas regulation was introduced in 2015, it resulted in a significant price increase for high-pressure GWP refrigerants. 'Kraftringen' therefore wants to investigate which conversion options there are for R134a, partly to reduce costs, but also to minimize the climate impact of the business.

     

    Different refrigerants have been compared with regard as to how they affect the plants performance. Moreover, it has been investigated which refrigerants are in the correct pressure range with regard to what the plants compressor and pipes are designed for. The survey has been done by performing theoretical calculations based on measured values from when the heat pumps operate at maximum load. In the refrigerant selection process, the same evaporation and condensation temperature as during the measuring was used.

     

    In the study we found two refrigerants, R152a and R450A, which would serve as conversion options in terms of them being in the correct pressure and temperature range. Both options have lower GWP and a higher heat factor than the current refrigerant R134a. However, R152a is flammable and has a higher degree of safety than the other two refrigerants.

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  • 23.
    Andersson, Christopher
    et al.
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Karlsson, Emil
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Energieffektivisering till sjöss: Inom linjetrafik2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna studie handlade om att undersöka vilka energireducerande metoder som åtta svenska rederier inom linjetrafiken har valt att tillämpa ombord på sina fartyg. Detta för att kunna ge en bild om vilka eventuellt nya system och metoder framtida sjömän står inför. Metoden som användes var genom ett utskickat frågeformulär där berörda rederier kunde svara på frågor angående deras energibesparingar. Även rederiernas hemsidor undersöktes för att kunna få en djupare insikt om vilka energibesparande metoder rederierna använde sig av. Sedan söktes vidare information om dessa energibesparande metoder för att kunna ge en beskriva dem. Slutsatsen som drogs av studien visade att nästan alla undersökta rederier tillämpar någon form av energibesparande åtgärder, men endast fyra av de tillfrågade åtta nämnde att de hade visioner som de strävade efter att uppnå. Studien hade en låg svarsfrekvens vilket kan indikera på att rederierna antingen inte vill dela med sig av sin energipolicy, eller så är denna policy helt avsaknad.

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  • 24.
    Andersson, Daniel
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Petter, Andersson
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Frikyla: En möjlighet för Östersjöfarten att spara energi?2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To maintain a comfortable climate on board ships, cooling is necessary during the warm period of the year which requires energy. This thesis is a survey about whether so-called free cooling could reduce this energy consumption. The ROPAX-ferry Finntrader trafficking the route Malmö–Travemünde has been used as an example.

    This survey was carried out by creating a calculation model in which a brine system with a possibility of free cooling was connected to Finntrader’s current HVAC-system, alongside the current chillers. Statistics of air temperature, air humidity and sea water temperature was acquired for the period 2013-2015 and were inserted into the calculation model. These calculations showed that a certain amount ofenergy could be saved with free cooling, how much depending on the effectiveness of the heat exchangers.

    The amount of energy that could be saved was quite small compared to the cost of the components required by the model.

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  • 25.
    Andersson Schneider, Katja
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Återvinning av restvärme i en biogasanläggning: Undersökning om värmepump som utnyttjar värme från rötrest i Hagelrums Gård/Biogas anläggning2021Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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  • 26.
    Antonov, Tyurker
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Tordsson, Jan
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Filtrering av slipdamm: Förslag på nytt filtreringssystem för energibesparing2014Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Det här examensarbetet består i att beräkna potentialen för kostnadsbesparingar vid byte till ett nytt filtersystem på Spring Systems AB i Torsås. I genomförandet ingår mätningar och beräkningar av luftflöden och effektförbrukning. Förslag ges även på nytt filtersystem.

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  • 27.
    Ausmeel, Erik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Gannholm, Botvid
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Dataanalys av en ny avfrostningsrutin på en kyl- och frysanläggning: En studie gjord hos Freezing Food Småland Öland AB2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is about a change in the food company Freezing Food Småland Öland AB’s defrosting routine for their evaporators in the freezer warehouse. The change was that the defrosting time and maximum temperature were reduced and that the time between defrostings now takes place every other night instead of every night.

    The aim was to examine whether the change in the routine had contributed to a reduction in energy consumption compared to before the change was made by also examining factors other than defrosting itself that might affect energy consumption.

    The method was to collect and analyze large amounts of data provided by the company and then reduce them to manageable figures. Data for local outdoor temperatures were also collected. This calculated averages for a given time period for energy consumption, warehousing and outdoor temperature.

    The results showed a decrease in energy consumption, the proportion due to the change in defrosting procedures left the investigation unanswered. The outdoor temperature should have reduced the power requirement, at the same time the storage should have increased it. It was concluded that more time needed to pass,and a new study needed to be produced after the defrosting routine was changed to allow for a safer assessment. 

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  • 28.
    Babashova, Nazrin
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Rajabli, N. F.
    Azerbaijan National Academy of Sciences, Azerbaijan.
    Rustamov, R. B.
    Azerbaijan National Academy of Sciences, Azerbaijan.
    Review on the challenges and the future of solar cell for space applications2020In: International Journal on Technical and Physical Problems of Engineering, ISSN 2077-3528, Vol. 12, no 3, p. 36-40Article in journal (Refereed)
    Abstract [en]

    Solar power systems are one of the major energy sources for spacecrafts and satellites. The first ever satellite was supplied by electricity generated via silicon based solar cells. Thus, solar arrays play integral role for space environment applications. However, space industry encounters various difficulties related to solar cells, and the main challenge is impact of radiation on the performance of solar units. Destructive nature of radiation has adverse effect on solar power systems causing certain damages leading to loss of efficiency and other negative consequences. In addition, there are other issues such as temperature and vacuum environment causing degradation of solar cells which also should be paid particular attention. In this paper, the physics of semiconductors, the history and importance of solar photovoltaics in space industry, the effect of radiation and techniques which can help to reduce or fix the negative impact of radiation, other challenges related to solar power systems, and the future of solar cells are reviewed.

  • 29.
    Bagherpour, Mohammad Bagher
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Amirkabir University of Technology, Iran.
    Nikazar, Manouchehr
    Amirkabir University of Technology, Iran.
    Welander, Ulrika
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Bonakdarpour, Babak
    Amirkabir University of Technology, Iran.
    Sanati, Mehri
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Effects of irrigation and water content of packings on alpha-pinene vapours biofilteration performance2005In: Biochemical engineering journal, ISSN 1369-703X, E-ISSN 1873-295X, Vol. 24, no 3, p. 185-193Article in journal (Refereed)
    Abstract [en]

    The main objective of this investigation is to determine the effect of different physical parameters on the performance of biofilters, treating hydrophobic compounds. In this respect, the effects of irrigation and water content of packings on the removal efficiency of bed in different pollutant loading rates, and gas phase flow rates, is studied. Alpha-pinene, which is produced from variety of industrial wood products, pulp and paper industries, and fragrance production units, has been selected as a model compound. Since the effectiveness of biofiltration depends strongly upon water solubility of compounds, in the case of alpha-pinene (2.5 ppm, at 25 ◦C), the process of waste gas treatment is faced with difficulties. In this paper, it is shown that performance of biofilters, treating hydrophobic contaminants, declines due to irrigation. This reduction is detected by an increase in the outlet concentration from 11% up to 22.5%. Its magnitude depends on the gas velocity inside the biofilter and outlet concentration of the bed. The result indicated that pore blocking along the bed has less effect on the performance reduction than diffusion coefficient. Also the inhibitory effects of velocity on biodegradation are considerably higher than the effects of concentration. In addition, this compost-based biofilter shows noteworthy higher elimination capacities in comparison with previous studied biofiltration systems. In this study, a maximum elimination capacity of 227 gm−3 of packing h−1 is achieved by 95% of removal efficiency. The maximum concentration in the inlet gas was 650 mgm−3.

  • 30.
    Baldi, Francesco
    et al.
    École Polytechnique Fédérale de Lausanne, Switzerland.
    Ahlgren, Fredrik
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Nguyen, Tuong-Van
    Polytechnic School-University of São Paulo, Brazil;Technical University of Denmark, Denmark.
    Thern, Marcus
    Lund University, Sweden.
    Andersson, Karin
    Chalmers University of Technology, Sweden.
    Energy and exergy analysis of a cruise ship2018In: Energies, E-ISSN 1996-1073, Vol. 11, no 10, p. 1-41, article id 2508Article in journal (Refereed)
    Abstract [en]

    In recent years, the International Maritime Organization agreed on aiming to reduce shipping’s greenhouse gas emissions by 50% with respect to 2009 levels. Meanwhile, cruise ship tourism is growing at a fast pace, making the challenge of achieving this goal even harder. The complexity of the energy system of these ships makes them of particular interest from an energy systems perspective. To illustrate this, we analyzed the energy and exergy flow rates of a cruise ship sailing in the Baltic Sea based on measurements from one year of the ship’s operations. The energy analysis allows identifying propulsion as the main energy user (46% of the total) followed by heat (27%) and electric power (27%) generation; the exergy analysis allowed instead identifying the main inefficiencies of the system: while exergy is primarily destroyed in all processes involving combustion (76% of the total), the other main causes of exergy destruction are the turbochargers, the heat recovery steam generators, the steam heaters, the preheater in the accommodation heating systems, the sea water coolers, and the electric generators; the main exergy losses take place in the exhaust gas of the engines not equipped with heat recovery devices. The application of clustering of the ship’s operations based on the concept of typical operational days suggests that the use of five typical days provides a good approximation of the yearly ship’s operations and can hence be used for the design and optimization of the energy systems of the ship.

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  • 31.
    Berg, Mikael
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Närström, Patrik
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Checklista för start av ångpanna av typ cirkulerande fluidbädd via anläggningens styr- och övervakningssystem på Örtoftaverket2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete är utfört på efterfrågan av Kraftringen AB för deras bioeldade kraftvärmeverk på Örtofta, cirka en mil utanför Lund. Projektet grundar sig i en avsaknad av lättanvänd befintlig dokumentation som beskriver kall och varmstart för deras 110 MW virvelbäddspanna tillverkad av Foster-Wheeler. Det fanns sedan pannan byggdes startmanualer, men dessa är otroligt stora, komplexa och svåranvända. Fokuset på detta examensarbete är därför att framställa en tydlig och lättanvänd startinstruktion i form av en checklista som beskriver kall och varmuppstart i en kronologisk steg för steg metod. Den slutgiltiga checklistan är utformad för att användas tillsammans med pannans användargränssnitt. För att uppnå våra mål har vi läst och sammanfattat all relevant panndokumentation samtidigt som vi har utfört en rad intervjuer av pannoperatörer och rådfrågat om deras åsikter om checklistans utformning.

  • 32.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Usage of Biofuels in Sweden2013In: CSR-2 Catalyst for renewable sources: Fuel, Energy, Chemicals Book of Abstracts / [ed] Vadim Yakovlev, Boreskov Institute of Catalysis, Novosibrisk, Russia: Boreskov Institute of Catalysis , 2013, p. 5-7Conference paper (Refereed)
    Abstract [en]

    In Sweden, biofuels have come into substantial use, in an extent that are claimed to be bigger than use of fossil oil. One driving force for this have been the CO2-tax that was introduced in 1991 (1). According to SVEBIO:s calculations (2) based on the Swedish Energy Agency´s prognosis, the total energy consumption in Sweden 2012 was 404 TWh. If the figure is broken down on the different energy sources (figure 1) one can see that the consumption roughly distribute in three different, equally sized, blocks, Biofuels, fossil fuels and water & nuclear power. The major use of the fossil fuels is for transport and the water & nuclear power is used as electric power. The main use of the biofuels is for heating in the industrial sector and as district heating. In 2009 the consumption from those two segments was 85 TWh, and 10 TWh of bio power was co-produced giving an average biomass to electricity efficiency of 12%. This indicates a substantial conversion potential from hot water production to combined heat and power (CHP) production. in Sweden 2013 broken down on the different energy sources. In 2006 the pulp, paper and sawmill industry accounted for 95% of the bio energy consumption in the industrial sector, and the major biofuel consumed was black liquor (5). However, the pulp and paper industries also produced the black liquor in their own processes. The major energy source (58%) for district heating during 2006 was woody biomass (chips, pellets etc.) followed by waste (24%), peat (6%) and others (12%) (5). The use of peat has probably decreased since 2006 since peat is no longer regarded as a renewable energy source. While the use of biofuel for heating purpose is well developed and the bio-power is expected to grow, the use in the transport sector is small, 9 TWh or 7% in 2011. The main consumption there is due to the mandatory addition (5%) of ethanol to gasoline and FAME to diesel (6). The Swedish authorities have announced plans to increase the renewable content to 7.5 % in 2015 on the way to fulfill the EU’s goal of 10 % renewable transportation fuels in 2020. However the new proposed fuel directive in EU says that a maximum of 5% renewable fuel may be produced from food sources like sugars and vegetable oils. Another bothersome fact is that, in principle, all rape seed oil produced in Sweden is consumed (95-97%) in the food sector, and consequently all FAME used (in principle) in Sweden is imported as FAME, rape seed oil or seed (6). In Sweden a new source of biodiesel have emerged, tall oil diesel. Tall oil is extracted from black liquor and refined into a diesel fraction (not FAME) and can be mixed into fossil diesel, i.e. Preem Evolution diesel. The SUNPINE plant in Piteå have a capacity of 100 000 metric tons of tall oil diesel per annum, while the total potential in all of Sweden is claimed to be 200 000 tons (7). 100 000 tons of tall oil corresponds to 1% of the total diesel consumption in Sweden. in Sweden for 2010 and a prognosis for 2014. (6). Accordingly, the profoundest task is to decrease the fossil fuel dependency in the transport sector, and clearly, the first generation biofuels can´t do this on its own. Biogas is a fuel gas with high methane content that can be used in a similar way to natural gas; for instance for cooking, heating and as transportation fuel. Today biogas is produced by fermentation of waste (municipal waste, sludge, manure), but can be produced by gasification of biomass, for instance from forest residues such as branches and rots (GROT in Swedish). To get high efficiency in the production, the lower hydrocarbons, mainly methane, in the producer gas, should not be converted into synthesis gas. Instead a synthesis gas with high methane content is sought. This limits the drainage of chemically bonded energy, due to the exothermic reaction in the synthesis step (so called methanisation). In 2011 0.7 TWh of biogas was produced in Sweden by fermentation of waste (6) and there were no production by gasification, at least not of economic importance. The potential seems to be large, though. In 2008 the total potential for biogas production, in Sweden, from waste by fermentation and gasification was estimated to 70 TWh (10 TWh fermentation and 60 TWh gasification) (8). This figure includes only different types of waste and no dedicated agricultural crops or dedicated forest harvest. Activities in the biogas sector, by gasification, in Sweden are the Göteborgs energi´s Gobigas project in Gothenburg and Eon´s Bio2G-project, now pending, in south of Sweden. If the producer gas is cleaned and upgraded into synthesis gas also other fuels could be produced. In Sweden methanol and DME productions are planned for in the Värmlands metanol-project and at Chemrecs DME production plant in Piteå.

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  • 33.
    Brandin, Jan
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Einvall, Jessica
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Sanati, Mehri
    The technical feasibility of biomass gasification for hydrogen production2005In: Catalysis Today, ISSN 0920-5861, E-ISSN 1873-4308, Vol. 106, no 1-4, p. 297-300Article in journal (Refereed)
    Abstract [en]

    Biomass gasification for energy or hydrogen production is a field in continuous evolution, due to the fact that biomass is a renewable and CO2 neutral source. The ability to produce biomass-derived vehicle fuel on a large scale will help to reduce greenhouse gas and pollution, increase the security of European energy supplies, and enhance the use of renewable energy. The Värnamo Biomass Gassification Centre in Sweden is a unique plant and an important site for the development of innovative technologies for biomass transformation. At the moment, the Värnamo plant is the heart of the CHRISGAS European project, that aims to convert the produced gas for further upgrading to liquid fuels as dimethyl ether (DME), methanol or Fischer–Tropsch (F–T) derived diesel. The present work is an attempt to highlight the conditions for the reforming unit and the problems related to working with streams having high contents of sulphur and alkali metals.

  • 34.
    Brandin, Jan
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Hulteberg, Christian
    Biofuel-Solution AB, Limhamn .
    Multi-function catalysts for glycerol upgrading2010Conference paper (Other academic)
    Abstract [en]

    During the last three years Biofuel-Solution, a privately held Swedish entity, has developed an IP-portfolio around gas-phase glycerol conversion into medium-value chemicals. The targeted chemicals have large to very large markets, to allow for use by more than a fraction of the glycerol available today without impacting the cost of the product. The reason behind is that glycerol is a by-product from the biofuel industry, including biodiesel and bioethanol. This indicates large production volumes, even though the glycerol is a fraction of the fuel produced. A by-product from any fuel process will be vast and therefore any chemical produced from this side-product will have to have a large market to offset it to. In order to avoid changing the fundamental market behavior, similar to what the biodiesel industry has done to the glycerol market.

    In the course of this work, several end-products have been targeted. These include plastic monomers, mono-alcohols and energy gases; using acrolein as a common starting point. To produce chemicals with high purity and efficiency, selective and active catalysts are required. For instance, a process for producing propionaldehyde and n-propanol has been developed to the point of demonstration and commercialization building on the gas-phase platform.

    By developing multi-function catalysts which perform more than one task simultaneously, synergies can be reached that cannot be achieved with traditional catalysts. For instance, by combining catalyst functionalities, reactions that are both endothermic and exothermic can be performed simultaneously.

    This mean lower inlet reactor temperatures (in this particular case) and a more even temperature distribution. By performing the dehydration of glycerol to acrolein in combination with another, exothermal reaction by-products can be suppressed and yields increased.

    It also means that new reaction pathways can be achieved, allowing for new ways to produce chemicals and fuels from glycerol. As in the case of ethane production from acrolein, where a catalyst surface has been devised where acrolein is first adsorbed. The actual mechanism is unknown but in speculation, the adsorbed acrolein is decarbonyled into ethylene and carbon monoxide on a first reaction site. The formed carbon monoxide diffuses to another active site, where it reacts with water through the so called water-gas shift reaction to carbon dioxide and hydrogen. Said carbon dioxide leaves as an end-product, and the hydrogen diffuses to another active site where it reacts with ethylene to form ethane. This gives a way of producing energy gases from glycerol in a very compact reactor set-up, effectively reducing footprint and capital cost and increasing productivity of an installation.

  • 35.
    Brandin, Jan
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Hulteberg, Christian
    Biofuel-Solution AB, Malmö.
    Levaue, Andreas
    Biofuel-Solution AB, Malmö.
    Green LPG2010Report (Other academic)
    Abstract [en]

    The use of energy gases with renewable origins will become important with diminishing fossil resources. This as the infrastructure of the gaseous fuels is well built out and the distribution networks already exist. LPG is one of the most versatile fuels around, perfect for rural areas and in many other applications. The fossil origin of the fuel will, in today’s climate and environmental debate, however position it as a thing of the past and not part of the future energy supply. The technology and development performed under this and previous programs with the Swedish Gas Centre will however suggest a way to bridge this conception and make LPG a part of the future energy mix. A good starting point for two and three carbon energy gases is glycerine, with its three carbon backbone. The reason for focusing on glycerine is its benign chemical nature, it is:• Harmless from a toxic standpoint• Chemically inert• Non-corrosive• Relatively high energy density• Zero carbon dioxide emissions It is also readily available as the production of biofuels (from which glycerine is a sideproduct) in the world has increased markedly over the last 10 year period. This glut in the glycerol production has also lowered worldwide prices of glycerine.Since the key step in producing energy gases from glycerol is the dehydration of glycerol to acrolein, this step has attracted much attention during the development work. The step has been improved during the performed work and the need for any regeneration of the catalyst has been significantly reduced, if not omitted completely. This improvement allows for a simple fixed bed reactor design and will save cost in reactor construction as well as in operating costs of the plant. The same conclusion can be drawn from the combination of the two functionalities (dehydration and hydrogenation) in designing a catalyst that promote the direct reaction of 1-propanol to propane in one step instead of two. The experiments with the decarbonylation of acrolein to form ethane show that the catalyst deactivation rates are quite rapid. The addition of noble metal to the catalyst seems to improve the longevity of the catalyst, but the coking is still too severe to provide for a commercially viable process. It is believed that there is a possible way forward for the decarbonylation of acrolein to ethane; it will however require additional time and resources spent in this area. In this work it has been shown that all of the catalytic steps involved in the production of propane from glycerol have sufficient longterm stability and endurance and it is motivated to recommend that the project continues to pilot plant testing stage.

  • 36.
    Brandin, Jan
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Tunér, Martin
    Lunds Tekniska Högskola.
    Odenbrand, Ingemar
    Lunds Tekniska Högskola.
    Small Scale Gasifiction: Gas Engine CHP for Biofuels2011Report (Other academic)
    Abstract [en]

    In a joint project, Linnaeus University in Växjö (LNU) and the Faculty of Engineering at Lund University (LTH) were commissioned by the Swedish Energy Agency to make an inventory of the techniques and systems for small scale gasifier-gas engine combined heat and power (CHP) production and to evaluate the technology. Small scale is defined here as plants up to 10 MWth, and the fuel used in the gasifier is some kind of biofuel, usually woody biofuel in the form of chips, pellets, or sawdust. The study is presented in this report.

    The report has been compiled by searching the literature, participating in seminars, visiting plants, interviewing contact people, and following up contacts by e-mail and phone.

    The first, descriptive part of the report, examines the state-of-the-art technology for gasification, gas cleaning, and gas engines. The second part presents case studies of the selected plants:

    • Meva Innovation’s VIPP-VORTEX CHP plant
    • DTU’s VIKING CHP plant
    • Güssing bio-power station
    • Harboøre CHP plant
    • Skive CHP plant

    The case studies examine the features of the plants and the included unit operations, the kinds of fuels used and the net electricity and overall efficiencies obtained. The investment and operating costs are presented when available as are figures on plant availability. In addition we survey the international situation, mainly covering developing countries.

    Generally, the technology is sufficiently mature for commercialization, though some unit operations, for example catalytic tar reforming, still needs further development. Further development and optimization will probably streamline the performance of the various plants so that their biofuel-to-electricity efficiency reaches 30-40 % and overall performance efficiency in the range of 90 %.

    The Harboøre, Skive, and Güssing plant types are considered appropriate for municipal CHP systems, while the Viking and VIPP-VORTEX plants are smaller and considered appropriate for replacing hot water plants in district heating network. The Danish Technical University (DTU) Biomass Gasification Group and Meva International have identified a potentially large market in the developing countries of Asia.

    Areas for suggested further research and development include:

    • Gas      cleaning/upgrading
    • Utilization      of produced heat
    • System      integration/optimization
    • Small scale      oxygen production
    • Gas engine      developments
    Download full text (pdf)
    Gas Engine CHP for Biofuels.pdf
  • 37.
    Börjesson, Joakim
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Evers, Johan
    Maskinbefäls utbildning på integrerade övervakningssystem ombord nybyggda fartyg2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During construction of new ships or modernization of ships, integrated automation systems is often installed in the engine control room. It is of importance that the responsible engine officers are familiar with how the system works and that they can perform troubleshooting if eventual faults occur. The aim of the present study is to investigate whether the engineer officer get enough training on new integrated surveillance systems to perform their duties in a safe and secure manner. In this study a questionnaire was sent to engine officers signed on new ships where they got the opportunity to give their answer how they experience the possibility to be trained and acquire knowledge how the systems work. The majority of the engine officers who answered the questionnaires felt comfortable to operate the ship safely. The study showed that the training courses offered often were product specific instead of installation specific, which was not optimal because there can be differences between construction and handling after installations of the same products. The survey showed that a majority of the officers had not been offered training on the monitoring system. The officers who were not offered training expressed a wish to be able to participate in training. Training on the system is offered by the manufacturer but often only a few of the engine officers is offered training by the shipping company. Earlier studies show that crews that participates in the building and delivery process on the shipyard or during installation of a new system receives training on site, the officers that come onboard as reliever after trial run, maiden voyage or during normal operation often have to learn by doing. The conclusion is that the officers should be given the opportunity to participate in training before signing on and also a follow up training course after working with the system for a while. To give the relieving officers a chance to familiarize themselves and assimilate knowledge of the system, there have to be more time available in conjunction with leave.

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    fulltext
  • 38.
    Cao, Wenhan
    et al.
    University of Strathclyde, UK.
    Li, Jun
    University of Strathclyde, UK.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Zhang, Xiaolei
    University of Strathclyde, UK.
    Release of potassium in association with structural evolution during biomass combustion2021In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 287, p. 1-9, article id 119524Article in journal (Refereed)
    Abstract [en]

    A mechanistic understanding of potassium release is essential to mitigate the potassium-induced ash problems during biomass combustion. This work studies the effects of operational condition on the potassium release and transition during the combustion of wheat straw, and elucidate the release potential of potassium associated with the structural change of biomass particles. The combustion tests were carried out in a laboratory-scale reactor, working in a wide range of temperatures and heating rates. It was found that the combustion of biomass sample at a temperature up to 1000 °C results in a release of over 60% of its initial potassium content. Raising the heating rate from 8 °C/min to 25 °C/min could lead to an additional release of up to 20% of the initial amount of potassium. A three-stage potassium release mechanism has been concluded from this work: the initial-step release stage (below 400 °C), the holding stage (400–700 °C) and the second-step release stage (above 700 °C). Comprehensive morphology analysis with elemental (i.e. K, S, O, Si) distribution was carried out; the results further confirmed that potassium is likely to exist inside the stem-like tunnel of biomass particles, mainly in forms of inorganic salts. During the heating-up process, the breakdown and collapse of biomass particle structure could expose the internally located potassium and thus accelerate the release of potassium and the transform of its existing forms. Lastly, a detailed temperature-dependent release mechanism of potassium was proposed, which could be used as the guidance to mitigate the release of detrimental potassium compounds by optimising the combustion process.

  • 39.
    Cedergren, Linnea
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Analys av Torkprocess förgasare Emåmejeriet2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I Sverige finns det stor potential för att utnyttja förgasning av biomassa för el- och värmeproduktion. Forskning och utveckling går framåt både nationellt och internationell men det finns en del kvar för att få förgasningstekniken kommersiell. Vid förgasning av biomassa är fukthalten ett stort problem, det försämrar förgasningsprocessen och minskar på processens värmevärde. Det kan lösas genom att använda sig av en bränsletork.

    I detta arbete presenteras en energi- och massbalans över en torkprocess som är installerad på en förgasningsanläggning i mikroskala på Emåmejeriet i Hultsfred. Analysen kommer att bidra till en större förståelse för hur torkningen fungerar och hur det påverkar fukthalten på utgående bränsle. En bra torkprocess bidrar till en förbättrad förgasningsprocess i framtiden.

    Resultatet visar att torken torkar bränslet och ger en låg fukthalt som gör att förgasaren fungerar bra. Luften till utloppet av torken har en temperatur på 20 grader och har en relativ fuktighet på 76 % vilket innebär att luften inte blir mättad i torken. Det visar att det finns mer utrymme för att göra en förbättring.

    Enligt mätningar som har gjorts på fukthalten visar att torken lyckas att torka bränsle med en fukthalt på 30-40% till en fukthalt på 5-10%. Den till torkprocessens tillförada värme är spillvärme från förgasaren med en effekt på 23.6 kW och torkeeffekte, alltså den effekt som krävs för att förånga vattnet i bränslet ger 14.5 kW. 

    Download full text (pdf)
    Analys av Torkprocess förgasare Emåmejeriet
  • 40.
    Dale, Virginia H.
    et al.
    Oak Ridge Natl Lab, USA.
    Kline, Keith L.
    Oak Ridge Natl Lab, USA.
    Parish, Esther S.
    Oak Ridge Natl Lab, USA.
    Cowie, Annette L.
    Univ New England, Australia.
    Emory, Robert
    Weyerhaeuser Co, USA.
    Malmsheimer, Robert W.
    SUNY Coll Environm Sci & Forestry, USA.
    Slade, Raphael
    Imperial Coll London, UK.
    Smith, Charles Tattersall (Tat), Jr.
    Univ Toronto, Canada.
    Wigley, Thomas Bently (Ben)
    NCASI, USA.
    Bentsen, Niclas S.
    Univ Copenhagen, Denmark.
    Berndes, Goran
    Chalmers University of Technology.
    Bernier, Pierre
    Canadian Forest Serv, Canada.
    Brandao, Miguel
    Inst Soil Sci & Plant Cultivat, Poland.
    Chum, Helena L.
    NREL, USA.
    Diaz-Chavez, Rocio
    Imperial Coll London, UK.
    Egnell, Gustaf
    Swedish University of Agricultural Science.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Schweinle, Jorg
    Thunen Inst Int Forestry & Forest Econ, Germany.
    Stupak, Inge
    Univ Copenhagen, Denmark.
    Trianosky, Paul
    Sustainable Forestry Initiat Inc, USA.
    Walter, Arnaldo
    State Univ Campinas UNICAMP, Brazil.
    Whittaker, Carly
    Rothamsted Res, UK.
    Brown, Mark
    Univ Sunshine Coast, Australia.
    Chescheir, George
    NCSU, USA.
    Dimitriou, Ioannis
    Swedish University of Agricultural Science.
    Donnison, Caspar
    Univ Southampton, UK.
    Eng, Alison Goss
    US Dept Energy DOE, USA.
    Hoyt, Kevin P.
    Univ Tennessee, USA.
    Jenkins, Jennifer C.
    Enviva LP, USA.
    Johnson, Kristen
    US Dept Energy DOE, USA.
    Levesque, Charles A.
    Innovat Nat Resource Solut LLC, USA.
    Lockhart, Victoria
    Resource Management Serv LLC, USA.
    Negri, Maria Cristina
    Argonne Natl Lab, USA.
    Nettles, Jami E.
    Weyerhaeuser Co, USA.
    Wellisch, Maria
    Agr & Agri Food Canada, Canada.
    Status and prospects for renewable energy using wood pellets from the southeastern United States2017In: Global Change Biology Bioenergy, ISSN 1757-1693, E-ISSN 1757-1707, Vol. 9, no 8, p. 1296-1305Article in journal (Refereed)
    Abstract [en]

    The ongoing debate about costs and benefits of wood-pellet based bioenergy production in the southeastern United States (SE USA) requires an understanding of the science and context influencing market decisions associated with its sustainability. Production of pellets has garnered much attention as US exports have grown from negligible amounts in the early 2000s to 4.6 million metric tonnes in 2015. Currently, 98% of these pellet exports are shipped to Europe to displace coal in power plants. We ask, 'How is the production of wood pellets in the SE USA affecting forest systems and the ecosystem services they provide?' To address this question, we review current forest conditions and the status of the wood products industry, how pellet production affects ecosystem services and biodiversity, and what methods are in place to monitor changes and protect vulnerable systems. Scientific studies provide evidence that wood pellets in the SE USA are a fraction of total forestry operations and can be produced while maintaining or improving forest ecosystem services. Ecosystem services are protected by the requirement to utilize loggers trained to apply scientifically based best management practices in planning and implementing harvest for the export market. Bioenergy markets supplement incomes to private rural landholders and provide an incentive for forest management practices that simultaneously benefit water quality and wildlife and reduce risk of fire and insect outbreaks. Bioenergy also increases the value of forest land to landowners, thereby decreasing likelihood of conversion to nonforest uses. Monitoring and evaluation are essential to verify that regulations and good practices are achieving goals and to enable timely responses if problems arise. Conducting rigorous research to understand how conditions change in response to management choices requires baseline data, monitoring, and appropriate reference scenarios. Long-term monitoring data on forest conditions should be publicly accessible and utilized to inform adaptive management.

  • 41.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Techno-economic performance of heat recovery air handling units for residential buildings in a sub-arctic climate2020In: The 12th International Conference on Applied Energy – ICAE2020, December 1-10, 2020, Bangkok/Virtual, ICAE , 2020, article id 404Conference paper (Refereed)
    Abstract [en]

    This study analysed the final and primary energy savings as well as cost-effectiveness of centralised and semi-centralised heat recovery air handling units (AHUs) configurations for existing and efficient variants of a district heated multi-dwelling building. The AHUs have counter-flow plate or rotary heat exchangers, and their performances for the building variants are analysed considering different economic scenarios and frost conditions. Very few studies have explored the techno-economic implications of such AHU configurations in the context of building retrofitting. The final energy savings is calculated on hourly basis using dynamic simulation modelling approach and is linked to the heat supply to calculate the associated primary energy savings. The cost-effectiveness is calculated considering investment costs as well as net present values of energy cost savings when the AHUs are applied. The results show that the primary energy savings and cost-effectiveness for heat recovery AHUs vary considerably for different contexts. The semi-centralised AHUs with rotary heat exchanger seem slightly more cost-effective among the analysed heat recovery configurations. Frost conditions and defrosting need have significant impact on the primary energy and economic performance of the AHUs.

  • 42.
    Edfors, Jonas
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Bremberg, Robin
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Liquid Natural Gas: A study of the environmental impact of LNG in comparison to diesel2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Liquefied Natural Gases (LNG) has been an alternative fuel in the marine industry for several years, but lately, the amount of ships that have been powered by methane has increased a lot. Some of the reasons for this is because LNG does not contain any sulfur and releases less nitrogen oxides than traditional maritime fuels. In this essay, LNG will be compared to diesel from an environmental perspective with focus on CO2 emissions and its equivalents. International Maritime Organization (IMO) implemented Energy Efficiency Design Index (EEDI) requirements that adjusts how much CO2 is allowed in the exhaust gas per produced kilowatt-hour (kWh). However, these requirements will increase in intervals in the future, the next one is coming 2022 for specific ship types. The method that is used to compare the fuels is Mole-calculations for LNG as well as diesel, then calculate the amount of carbon dioxide (CO2) and its equivalents they release. The results show that under optimal conditions, LNG was the superior choice. However, the maritime industry might have a problem with the requirements that will be introduced to greenhouse gas (GHG) emissions in 2050.

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    fulltext
  • 43.
    Edin, Albin
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Johansson, Erik
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Miljö- och ekonomisk utvärdering av energirenoverat småhus2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sverige har ett etappmål att minska utsläppen av växthusgaser med 59% år 2030 jämfört med år 2005 och även att energianvändningen ska vara 50% effektivare under samma period. En stor del av svenska småhus håller längre inte måttet för energieffektivitet och har därför stor potential att energieffektiviseras. 

    Denna rapport undersöker utfallet av ett småhus från 1970-talet som energirenoverats i Tingsryds kommun utifrån ett energi- och miljömässigt, ekonomiskt och socialt perspektiv. Energirenoveringen består av tilläggsisolerad vind, installation av solceller och byte av pelletspanna till bergvärmepump. Rapporten undersöker också ifall installation av FTX- ventilation och byte av fönster kan installeras kostnadseffektivt. 

    Husets energianvändning minskade med 129 kWh/(år*Atemp), vilket också minskade husets driftskostnader. Installation av FTX-ventilation och byte av fönster kan ytterligare sänka energianvändningen, men lönar sig inte ekonomiskt. Enligt husägaren finns heller inget behov av nytt ventilationssystem och bättre isolerad klimatskärm. Energirenovering av småhus från 1970-talet kan sägas vara fördelaktigt då energianvändningen minskar kostnadseffektivt. Det bidrar även till lägre CO2e-utsläpp utifrån bokföringsperspektivet och konsekvensanalys. 

    Download full text (pdf)
    fulltext
  • 44.
    Einvall, Jessica
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Sanati, Mehri
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. Bioenergiteknik.
    Impact of fly ash from biomass gasification on deactivation of reforming catalyst2006In: 12th Nordic Symposium in Catalysis-May 28-30-Trondheim-Norway, 2006, p. 132-133Conference paper (Other (popular science, discussion, etc.))
  • 45.
    Ericsson, Mats
    et al.
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Dzafic, Amir
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Värmepumpar ur ett driftsäkerhetsperspektiv: En feleffektsanalys på värmepumpssystem2012Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Värmepumpar har länge funnits på marknaden men de har på senare tid fått en ökad uppmärksamhet av media på grund av den bristande drifttillförlitligheten.

    Detta projekt syftar till att definiera svagheter i ett värmepumpsystem på en övergripande systemnivå med hjälp av en feleffektsanalys (FMEA).

    Projektet har delats upp i två delar, dels en informationssamlande del om systemuppbyggnaden, komponenterna och analysmetoden samt en intervjuande del där Per Olsson, tekniskt ansvarig på Euronom, fick hjälpa oss med bedömningen av felen.

    FMEA-metoden lämpar sig väl för värmepumpar då den är speciellt lämpligt för seriella system och processer där det inte finns några redundanser.

    Resultatet kan sammanfattas i ett par tydliga resultat. Alla fel som uppstår i systemet påverkar COP-talet negativt. Fel som har en hög allvarlighetsgrad behöver inte vara de som har högst riskpotential. Detta eftersom de kan vara lätta att upptäcka och sannolikheten att de inträffar kan vara låg. Det går inte heller att utse en komponent som är viktigast ur ett driftsäkerhetsperspektiv då alla komponenter samverkar och är beroende utav varandra.

  • 46.
    Eriksson, Daniel
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Hertin, Jonathan
    Utredning om förbättrande åtgärder för bränsleberedning på Nybro Energis nya kraftvärmeverk2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
  • 47.
    Faturachman, Danny
    et al.
    Darma Persada Univ, Indonesia.
    Yandri, Erkata
    Darma Persada Univ, Indonesia.
    Pujiastuti, Endang Tri
    Darma Persada Univ, Indonesia.
    Anne, Olga
    Klaipeda Univ, Lithuania.
    Setyobudi, Roy Hendroko
    Darma Persada Univ, Indonesia;Univ Muhammadiyah Malang, Indonesia.
    Jani, Yahya
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Susanto, Herry
    Darma Persada Univ, Indonesia.
    Purba, Washington
    Darma Persada Univ, Indonesia;Graha Mampang, Indonesia.
    Wahono, Satriyo Krido
    Indonesian Inst Sci, Indonesia.
    Techno-Economic Analysis of Photovoltaic Utilization for Lighting and Cooling System of Ferry Ro/Ro Ship 500 GT2021In: 1st International Conference on Bioenergy and Enviromentally Sustainable Agriculture Technology (ICoN-BEAT) / [ed] Setyobudi, RH Winaya, A Burlakovs, J Mel, M Anne, O, EDP Sciences, 2021, article id 00012Conference paper (Refereed)
    Abstract [en]

    The purpose of this study is to perform the techno-economic analysis of photovoltaic system utilization for lighting and cooling of Ferry Ro/Ro 500 GT. The world is facing a dilemma of increasing dependence on fossil energy with decreasing supply. This situation must be anticipated by all sectors by energy efficiency (EE) and utilizing renewable energy (RE). Especially for RE in the transportation sector, ships as consumers of oil energy can also take advantage of solar energy sources, for example for lighting and cooling. For that purpose, five steps must be taken. First, determine the design specifications. Second, determine the specifications of components of the PV system. Third, calculate the power required for lighting equipment. Fourth, calculate the power required for the cooling system. Fifth, make an investment comparison for propulsion systems between diesel engines and photovoltaic systems. The results show that the energy required for lighting and cooling system as well as for propulsion systems can be placed in the deck area of 148.8 m(2) for all system components, such as; PV modules, charge controllers, batteries, and inverter. This study can provide an overview of the use of PV system in designing the environmentally new or renovation ships.

  • 48.
    Flinkman, Matti
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Sikkema, Richard
    Wageningen Univ & Res Ctr WUR, Netherlands;European Commiss, Italy.
    Spelter, Henry
    USDA, USA.
    Jonsson, Ragnar
    European Commiss, Italy.
    Exploring the Drivers of Demand for Non-industrial Wood Pellets for Heating2018In: Baltic Forestry, ISSN 1392-1355, E-ISSN 2029-9230, Vol. 24, no 1, p. 86-98Article in journal (Refereed)
    Abstract [en]

    The targets for renewable energy in the European Union (EU) have resulted in a surge in the use of wood pellets. The EU-28 consumption has outgrown domestic production, resulting in increasing net imports. This study analyses the drivers of the use of pellets for heating (non-industrial pellets). An enquiry directed to biomass and pellet organizations indicates that country specific subsidies could be a driver for the purchase of pellet stoves and boilers, resulting in a base level of consumption of non-industrial pellets. Further, light heating oil and natural gas are considered the main heating sources substituted by wood pellets. Econometric analysis indicates that GDP is less important, while the price of wood pellets as well as the price of alternative energy carriers seem to be significant drivers. Models using different combinations of these variables account for 63% to 76% of the variation in non-industrial pellet demand. The results indicate the importance of considering competing fossil-based fuels when modelling wood pellet demand. This aspect is also relevant when new policy measures for a low carbon economy are applied, such as the levying of carbon taxes on fossil fuels.

  • 49.
    Fredriksson, Anna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mätvärdesbaserad metod för minskade emissioner i mindre förbränningsanläggningar2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    En mätvärdesbaserad metod har använts för att i den enskilda förbränningsanläggningen kunna visa vilka driftsätt som ger onormalt höga utsläpp. Tre olika typer av anläggningsdata har använts. Metoden fokuserar på gasfasreaktioner för att hållas oberoende av eldningsteknik. För att hålla nere beräkningstider och datorkapacitet fokuserar arbetet på summareaktioner och enkla samband vad gäller kemiska processer och förhållanden i eldstaden. 

    Download full text (pdf)
    fulltext
  • 50.
    Frenliden, Carl
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ljungman, Martin
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Sustainability evaluation of proposal for a decentralized office space.: Case study, Växjö, Sweden2022Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As the COVID-19 pandemic became widespread around the world, the need to be able to work from home became clear to help reduce the spread of the virus, while at the same time showing that working from home could be successful in the future. While working from home can be positive, it also has drawback as reduce social interactions, hard to set working boundaries and more. This paper examines the viability to introduce a decentralized office space trough environmental sustainability, economic sustainability and social sustainability for a reference apartment building and an energy renovated one compared to a centralized office space. This study shows that working from a decentralized office space will reduce emissions with better utilization of the apartment building, saving the companies money and having a reasonable payback period for investors, while giving employees better personaleconomic and more free time without compromising on the social sustainability from not meeting people and having a hard time to different on working hours and non-working hours. 

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