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  • 1.
    Andersson, Mari
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Willner, Sara
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Förluster i solfångare Avsvalning av rörsystemet i solfångarfält2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 2.
    Andersson, Mikael
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Volymberäkning med temperaturgrund: Beräkning av volymändringen i ackumulatortanken med hänsyn till nätets volymändring utifrån temperatur2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This work has been carried out on behalf of Sundsvall Energi AB, with the purpose of establishing a link between Sundsvall Energi AB:s accumulator in Granloholm and the urban network with a temperature base, and using this connection to get a better understanding of their leakage.

    During the project, a literature study and a survey of the company's current system, was conducted to gain an understanding of the system and the mission. The lack of similar work forced me to look at leak detection methods that were relevant even though they did not handle the same area altogether. On the other hand, counselors and staff members assisted in obtaining the information requested and gave advice and tips on aspects of the assignment that had not been included in the report before.

    The model was developed piece by piece during the work period, when no other work was found that could provide a proper framework for the work. The model has proven to be more accurate than its predecessor but also more difficult to implement.

    The thesis has shown how different energy systems can be from each other and how different, the different methods that are available to look and solve problems in the system are. The use of existing meters and instruments is not always reliable or available, and assumptions and occurrences must sometimes be made to get an overview picture and a valid basis.

  • 3.
    Astner, Måns
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Granskning av snabb pyrolys och hydropy- rolys för produktion av bioolja från trärester: Fyra undersökta tillverkningsmetoder med en teknisk och ekonomisk jämförelse2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Världens klimat- och miljöproblem är ett av dagens stora utmaningar samtidigt som alla resurser ska räcka till ett drägligt liv för en växande befolkning. För att klara dessa utmaningar bör bland annat världens energisystem övergå till 100% förnybart, vilket innebär att tillförseln av fossil energi måste fasas ut och ersät- tas. Fossila bränslen är en ändlig resurs jämfört med biobränslen som kan agera substitut för att öka energitillförseln och minska miljöpåverkan. Denna rapport bygger på att utvärdera fyra företag som levererar teknik för att omvandla bio- massa till biokol, bioolja samt biogas genom en pyrolysprocess. Utvärderingen skall resultera i ett beslutsunderlag för en uppdragsgivare som vill producera bioolja från restprodukter i ett sågverk där val av leverantör främst ska utgå ifrån hur mycket bioolja som kan produceras samt med så hög kvalitet som möjligt. De fyra företagen som undersöks är Steeper Energy och Licella som levererar hydrpyrolysteknik samt BTG-BTL och Biogreen som levererar teknik för snabb pyrolys. Rapporten innehåller även en ekonomisk jämförelse mellan de två teknikerna snabb pyrolys och hydropyrolys. Undersökningen har visat att hydropyrolys ger den bästa slutprodukten men att snabb pyrolys är den mest ekonomiskt lönsamma. Steeper Energy anses vara den bästa kandidaten för än- damålet när det kommer till kvalité och kvantitet av produkt samt energieffekti- vitet.

  • 4.
    Björkqvist, Olof
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Fridén, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Energiåtervinning vid LC-raffinering – Förstudie2008Report (Other academic)
    Abstract [en]

    Normally, steam recovery from a conventional low consistency (LC) mechanical pulprefining system is not possible. This is due to the fact that the temperature level in theLC-refiner is less than 100°C. The steam with such a low temperature and associatedpressure has limited value in the mill. In this project, we study a concept of increasingthe temperature in the refiner to a level were process steam with higher quality can berecovered. The temperature level can be increased by transferring heat from outgoingpulp or drainage to incoming pulp or water. This makes it possible to recover heat fromthe process.An initial estimate indicates that steam recovery from LC-refining systems may have agood economic potential. Three cases have been analyzed: Case A: Steam recovery incombination with pulp/pulp heat exchanging, Case B: Steam recovery in combinationwith a pressurized screw press and finally Case C: steam recovery in combination withpump/water heat exchanging.Case B show the best specific steam recovery, 87% kWh recovered steam per kWh usedelectricity. This concept has a lower technological uncertainty compared to cases A andC as it does not need heat exchanging from pulp.The specific heat recovery from case A and C is 78% and 82% respectively. However,the suggested heat exchangers used in these cases do not exist on the market today.There is hence a need for development of exchangers that can handle pulp with highviscosity. The technological risk associated with the screw press scenario is lower and itis likely that this concept is easier to implement.

  • 5.
    Breitkreuz, Rikard
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Ackumulering av ånga: Effektivare ångproduktion vid Akzo Nobel Stockvik2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report aims to examine if it is possible to install an accumulator for steam-accumulation at the steam plantof Akzo Nobel Stockvik and to calculate its dimensions. The accumulator’spurpose is to level out the steam production when there is intermittent usage of steam at different steamconsumers.

    Within site Stockvik it is possible to use internal fuels such as CO-gas and hy-drogengas for steam production, the use of internal fuel is both environmental and economically positive.When large steam demands occurit is not sufficient to only use internal fuels and oil has to be used to produce steam as backup to meet the steam demand.An accumulator can be used to store steam at low steam demand and use at high demand instead of producing steam with oil as fuel.

    An energy audit shows that the two major consumers also has very varying needs of steamwhich results in a need to use oil as backup fuel in boiler 3.This shows that there is a need of an accumulator in the system.

    The accumulator can be installed close to the steam plant which reduces the energy losses. Three accumulators havebeen calculated from an average effect of boiler 3. The accumulators havea total volume of 29, 70 and 112 m3. Large quantities of data from the steam process are digitally stored atAkzo Nobel, this data have been used to compare the different accumulators to the actual steam production 2015 and 2016.

    The profit of installing a steam accumulator is independent of the accumulator size but the cost of installing the accumulator increases with larger volume.The shortest payback period 4,4 years is when choosing the smallest accumulator, 29 m3.Environmental benefitsareachieved by a reduction of oil usage by350 m3/year whichreduces the CO2emissions by 1000 tons/yearand SO2emissions by 1,3 tons/year

  • 6.
    Danielski, Itai
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Fröling, Morgan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Diagnosis of buildings' thermal performance - a quantitative method using thermography under non-steady state heat flow2015In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 83, p. 320-329Article in journal (Refereed)
    Abstract [en]

    This study describes a quantitative method using thermography to measure the thermal performance of complete building envelope elements that are subjected to non-steady state heat flow. The method presumes that thermal properties of external walls, like conductivity, could still be obtained by a linear regression over values of independent measurements. And therefore could be used during fluctuating indoor and outdoor thermal conditions. The method is divided into two parts. First, the convection heat transfer coefficient is measured by heat flux meters (HFM) and thermography. And then, the overall heat transfer coefficient of a complete building element is measured by thermography to include all non-uniformities.

    In this study the thermal performance of a 140 mm thick laminated timber wall was measured. The wall was subjected to the outdoor weather conditions in Östersund, Sweden during January and February. The measurement values were found to have a large disparity as expected due to the rapid change in weather conditions. But still a linear regression with low confidence interval was obtained. The thermography results from a small uniform wall segment were validated with HFM measurements and 4% difference was found, which suggest that the two methods could be equally effective. Yet, thermography has the advantage of measuring surface temperature over large area of building element. The overall heat transfer coefficient of a large wall area was found to be 11% higher in comparison to the HFM measurements. This indicates that thermography could provide a more representative result as it captures areas of imperfections, point and linear thermal bridges.

  • 7.
    Eriksson, Alexander
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Tryckfall över värmeväxlare: En empirisk och teoretisk jämförelse av tryckfall över värmeväxlare2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Examensarbetet är utfört på uppdrag av Scandymet AB. Huvudsyftet med arbetet är att undersöka om deras kalkylprogram överdimensionerar tryckfallet vid produktionen av värmeväxlare. Scandymets värmeväxlare används ofta i tuffa industrimiljöer och har höga krav på effektivitet för uppvärmning eller nedkylning, samt att materialet är korrosionsbeständig. För att utföra denna undersökning konstruerades en flödesrigg som hanterar uppvärmning och cirkulation av varmvatten. Till flödesriggen konstruerades även en datalogger, som via en Arduino Uno samlar in information från temperatur- och tryckgivare.  Scandymet har tillverkat fyra olika modeller av värmeväxlare som undersöktes med olika hastigheter på värmebäraren. Ett Exceldokument behandlar informationen på minneskortet och beräknar det laborativa tryckfallet för varje testomgång. Det laborativa resultatet jämförs därefter med företagets kalkylark som kontroll beräknas teoretiskt i ett separat Exceldokument. Sammanställningen resulterar i att kalkylarket överdimensionerar tryckfallet med 26–53% beroende på modell av värmeväxlare och hastighet. För att utreda överdimensioneringen analyseras kalkylarket, där det visade sig att faktorerna för tryckstötmotståndet ζ och rörfriktionskoefficienten λ har antagits vara betydligt högre än vad empiriska data visar.

  • 8.
    Eriksson, Martin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Livcykelkostnad för ventilationssystem: En jämförelse mellan konventionell och hög luftomsättning för ökad kognitiv förmåga2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis two different ventilation systems have been designed and compared due to design, investment costs and life cycle costs. Option A was designed for conventional air circulation while Option B was designed to handle a relatively high air circulation. The idea for comparison came from new research that shows that a relatively high air flow and resulting lower carbon dioxide levels can have a big impact on the cognitive abilities of individuals within the system. Design and dimensioning of the systems has been done with software such as MagiCAD and Pro Unit. The work has shown clear differences in the design of each system. Option B requires much more space than option A. In some parts of the system, it is doubtful that alternative B is practical to install because of its needs for larger channel dimensions. Regarding the investment costs for each option this work has shown that option A is about 30% cheaper than alternative B when differences in design, demolition of existing parts, installation and new materials had been taken into consideration. This was a surprisingly small price difference in relation to what was expected. The comparison between life cycle costs of the two different alternatives has been a central part of this work. A model for calculating the life cycle costs of each system was created in Excel and the model showed that systems with relatively high air circulation could be preferable even at small additional costs for reduced cognitive performance for conventional flow systems. This thesis points out that more research is needed on how the air circulation in the ventilation system affects the cognitive skills of individuals within the system.

  • 9.
    Hammarström, Anton
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Utvärdering av potential för värmeåtervinning från laborationsutrustning: Möjligheten att använda en kylvattenbassäng som termiskt säsongslager2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    HETA Education in Härnösand has a steam power plant for educational purposes which is cooled with water from a 329 m³ underground basin. The purpose of this thesis has been to examine how the basin with the waste heat can be used as seasonal thermal energy storage with an existing 7.8 kW heat pump in order to heat the machine room of their lab building. A spreadsheet was created in Microsoft Excel in order to carry out the calculations. As no measurement data was available, a simulated scenario was created based on temperature statistics and the operating schedule for the power plant from the year 2017. Transmission losses were calculated for the basin and the machine room. For the basin, mostly observational data and knowledge among the staff were used, while the insulation for the machine room mainly had to be estimated based on the construction year. The result was that the heat pump, with the current operating schedule, could cover around 45% of the yearly heating demand of the machine room. Of the 276 GJ that were added through cooling of the power plant during a year, according to calculations, only 2,7% could be used for heating the machine hall, due to lacking insulation in the basin. The greatest limitations for achieving a higher heating coverage and a greater usage of the waste heat were assessed to be the placement in time of the power plant runs, and the effect of the heat pump. If the runs would be placed mainly in November–April, and the heat pump replaced with a 10 kW one, around 74% of the heating demand could be covered and 18 % of the waste heat used. Other things, such as increased insulation in the basin and larger water volume were also assessed to be able to increase the capacity of the basin as heat storage.

  • 10.
    Hedlund, Alexander
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering. FrontWay AB.
    Stengard, Anna-Karin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering. Sundsvall Energi AB.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    A simulation-based method for evaluation of energy system cooperation between pulp and paper mills and a district heating system: A case study2017In: 19 World academy of science, engineering and technology conference proceedings, 2017, Vol. 19, p. 1158-1164Conference paper (Refereed)
    Abstract [en]

    A step towards reducing greenhouse gases and energy consumption is to collaborate with the energy system between several industries. This work is based on a case study on integration of pulp and paper mills with a district heating system in Sundsvall, Sweden. 

    Present research shows that it is possible to make a significant reduction in the electricity demand in the mechanical pulping process. However, the profitability of the efficiency measures could be an issue, as the excess steam recovered from the refiners decreases with the electricity consumption. A consequence will be that the fuel demand for steam production will increase. If the fuel price is similar to the electricity price it would reduce the profit of such a project. If the paper mill can be integrated with a district heating system, it is possible to upgrade excess heat from a nearby kraft pulp mill to process steam via the district heating system in order to avoid the additional fuel need. The concept is investigated by using a simulation model describing both the mass and energy balance as well as the operating margin. Three scenarios were analyzed: reference, electricity reduction and energy substitution. The simulation show that the total input to the system is lowest in the Energy substitution scenario. Additionally, in the Energy substitution scenario the steam from the incineration boiler covers not only the steam shortage but also a part of the steam produced using the biofuel boiler, the cooling tower connected to the incineration boiler is no longer needed and the excess heat can cover the whole district heating load during the whole year. 

    The study shows a substantial economic advantage if all stakeholders act together as one system. However, costs and benefits are unequally shared between the actors. This means that there is a need for new business models in order to share the system costs and benefits. 

  • 11.
    Lindström, Klas
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Hur lönsamt är solel?: Förändras lönsamheten av solel i kombination med smarta elnät?2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, the aim has been to investigate whether smart grids will motivate an investment in solar cell installations. The report is primarily aimed at housing associations. To complete this, a literature study has been conducted. This resulted in what types of laws and regulations apply today and how they are used. The literature study also resulted in the different scenarios that were likely to occur in the future, and from this a result could be produced. The Scenarios that was chosen to look into was “what would happen if more people started driving electric cars, if the associations acted as electricity dealers and sold solar power to the members and two different types of storage, grid storage and battery storage”. Once the scenarios were established, the work started comparing these to see which one would give the best economic return. The result that could be obtained was that battery storage yielded the highest return but also the longest repayment period, which gave the lowest repayment time was storage in power grids. It was also found that the present value of a battery storage facility was lowest among the cases investigated, but on the other hand, storage in the power grid had the highest present value. It can be concluded that the best results could be obtained from storage in electric cars, avoiding the expensive in-vestment cost in batteries but at the same time maintaining the highest self-consuming degree therefore keeping the highest yield.

  • 12.
    Meurling, Axel
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Återvinning av värme från datahall: En ekonomisk jämförelse mellan kylmaskiner och frikyla2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As electricity consumption increases and more demanding equipment is installed, it is interesting to study which method is best suited for cooling off unwanted heat and if that heat can be used where it is desired. The aim of this report is to compare two solutions economically to cool two server halls adjacent to each other. The purpose of the report is that it should be the basis for an investment decision by the property owner. The operators in the server halls develop a total power of 104kW. The total area of the two halls of about 100m2 constitutes to only a small part of the 9877m2 large property in which they are located. The remaining part of the property serves as an upper secondary school. The work has been carried out by means of site visits, literature studies, energy consumption mapping, production of a duration chart and energy demand calculations. The property has a maximum power requirement of 350kW and consumes 956000kWh. The cooling is today supplied by three older cooling units. The heat developed in the server hall is used as primary heat for the school, but the property owner believes it is not as effective as it could be and that the system is unable to deliver sufficiently hot flow temperature. A heat pump solution would account for 75% of the power requirement would supply 262.5kW and 717000kWh, which means an energy coverage of 94%, which reduces the district heating power from 220kW to 87.5kW. A cooling machine solution with the specified cooling unit is capable of covering 67% of the power requirement and 86% of the energy demand. The district heating would decrease with 90kW from present values. The investment cost of the heat pump solution with boreholes is estimated at 2090000kr and for the cooling unit 750000kr. The net savings for 10 years will then be 2930000kr for the heat pumps while the cooling machine solution would be more expensive in operation than the existing solution. The net present value for the heat pumps after 10 years will amount to 1220000kr.

  • 13.
    Montagna Cimarelli Viktor, Donna
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Stream Identification in Pinch Analysis: Fixed and Flexible flows2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this project is to find an identification tag that can be used in a future automated pinch analysis tool. It can be used to further analyse composite curves and pinch results by tracking the original streams that was converted. In real life situations, retrofitting a process industries streams, can decrease heat demands and costs. A pinch analysis and a heat exchange network is created with fixed and flexible flows to show a recommendation on how the system model can handle this type of situations. The models have been created by hand with support from pinch literature and the calculations validated with mathematical software such as matlab and other graphing tools. The literature study and pinch modelling resulted in a recommendation of tagging Hstart and Hend for each individual stream. By using a geographical tag in a coordinate system the analyst will be able to find the original streams in the pinch analysis and composite curves. The project also resulted in a heating exchange network created from the fixed and flexible data set. The enthalpy differences between the ideal pinch result and the fixed data set is smaller than one might expect because of enthalpy abundance in the specific intervals.

  • 14.
    Nilsson, André
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Energilagring i byggnader: En litteraturstudie om batterilagring, vätgaslagring och en utredning om möjligheter till energilagring av förnyelsebar energi2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Energy consumption is increasing globally and because of this,

    increased energy production is necessary. Electricity from renewable

    sources is and will further be a key to meet the energy needs and

    perhaps the most important energy source is the sun. Umeå energi

    makes an investment in a photovoltaic system at Gammlia sports center

    in Umeå, and because of this, a study has been made on energy storage

    in combination with solar cells. Solar cells have a varied production,

    seen over the day and year. The solar cells only produce electricity when

    the sun is up, and energy storage is a possible solution for storing some

    of the energy produced during the day, to use later during the

    evening/night. The report's first section has two energy storage methods

    studied, battery storage and hydrogen storage. Methods for the

    operating principles, pros/cons and a statement whether they fit as

    energy storage in buildings has been made. In the second part,

    calculations have been made for the possibility of installing energy

    storage in Gammlia sports center for the electricity generated from the

    solar panels. The first part is made of a literature review of scientific

    reports and other web-based material. Energy estimates are based from

    the information provided from Umeå energy and the available methods

    of calculations on the web. Battery is an electrochemical storage shape

    and function to an anode, a cathode, and the electrolyte is used in all

    techniques. The advantage of batteries is the flexibility and low

    maintenance costs while the major drawback is the low energy density.

    Hydrogen storage using electrolysis is a method in which hydrogen

    produced from water and electricity. The advantage is the high energy

    density and environmentally friendly conversion. The main

    disadvantage is the high conversion losses. The survey on the

    possibilities for energy storage in the Gammlia sports facility, an

    investigation was made whether the plant could be made self-sufficient

    for electricity on the solar cells. It was costly that it was not feasible with

    the solar cell demodulation and storage technologies that are relevant in

    this study. A less comprehensive solution was found that involves

    daystorage in the summer months. Using batteries, energy produced on

    the day could be saved and used in the evening / night. This solution

    was feasible, purely technical, but not economical, as earnings were too

    small in comparison to investment cost.

     

  • 15.
    Nilsson-Böös, Viktor
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Differenstrycksregulatorer: En studie om hydronisk reglering av radiatorsystem med hjälp av differenstrycksregulatorer2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this work was to investigate in which types of systems where use of differential pressure controllers is possible. And to analyze which success factors using of differential pressure controllers can provide. The work was done with the help of a literature review and discussions with energy consultants at the company FVB Sweden AB. This work does not assume any specific case, but treat scenarios that could occur in reality. There are three main scenarios created to demonstrate the function and importance of differential pressure controllers in a heating system. These scenarios treat cases where one pump is supplying both homes and businesses, when buildings will be built in stages and when the pump supplies a group of properties comprising both one-pipe and two-pipe systems. The study has shown that in all three scenarios imbalance in flow will occur in the heating system, this is reported under the chapter result in the report. In cases where the problem is imbalance of flows, the problem can be solved by installing only a static control valve on the outgoing return line from the property. Financial calculations carried out in this work. These calculations are showing what the additional cost will be for a differential pressure controller, compared to a static control valve. Calculations that show the cost savings that can be made when installing a differential pressure regulator has also been done. The conclusion of this work is that in all three scenarios presented in the results section, a differential pressure controller should be installed to provide the heating system with a balanced flow. Although it is a more expensive alternative, cost savings can be achieved, which justifies the installation of a differential pressure controller in the heating system.

  • 16.
    Nordgren, Sofie
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    En hållbar framtid med solceller för Ljusdalshem: Solcellens betydelse i dagens samhälle samt projektering av en solcellsanläggning för elproduktion på ett flerbostadshus2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Solar cells are constantly evolving with regard to efficiency, and in connection with the modules' reduced purchasing costs, more and more people are becoming interested in solar energy. The sun is the purest source of energy, and there is a great potential for profitable plants in Sweden, given the amount of solar radiation. The project is to plan a solar cell facility for Ljusdalshem and calculating its profitability. Furthermore, the structure of the solar cell is investigated, which types of solar cells are present on the market today, and what factors affect the plan. The survey has been conducted with a literature study of printed sources with internet as a complement. Some of the informat-ion has also been collected from the staff at Ljusdalshem and from a supplier with experience in the area. The energy productions were carried out through manual calculations and two different calculation tools as a complement. Profitability is judged based on the present value method and the payoff method. The building has two suitable roof areas, one located to the south-east and one to the southwest. The different directions of the roof provide a larger production span over the day but inhibit overall solar energy production. The plant will consist of monocrystalline silica sols, inverters, and power optimizers. Together they can produce electricity corresponding to 17 percent of the annual consumption. Activities in the building are conducted during daytime, which fits well to receive produced energy from solar cells. Taking into account electricity price increase, discount factor, re-construction, and reinvestment modules, the present value has shown an investment that is not profitable. Investment support for solar power plants is available at the County Administ-rative Board, and is a prerequisite for the profitability of the plant. A profitable investment also requires that the electricity price increase is greater than assumed. Measures that reduce electricity consumption should be performed, therefore, the calculations are based on a lower consumption than the current one. An even lower power consumption would give another result, which is a reason for making more accurate calculations when the new annual consumption becomes known. The repayment period for the investment is longer than the technical life and thus does not contribute to the company's profitability with the assumed electricity price and other terms. Since the plant is to be regarded as a reference facility and Ljusdalshem has an environmental objective to achieve, there is an opportunity for investment despite the economic losses.

  • 17.
    Olsson, Anton
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Ekonomiskt utfall av bränsle och bränsleblandningar: En modell för framtagning av ång- och bränslekostnader2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Uppdragets huvudsakliga ändamål har varit att utveckla en modell för SCA Ortvikens pappersbruk, för beräkning av ångans momentankostnad. I rapporten bildas en uppfattning om hur Ortviken producerar papper och visar en överblick av fabrikens ångcentral, samt hur okända bränsleflöden kan tas fram. Därefter förklaras modellens konstruktion vilket inkluderar den information som krävs och hur den hämtas, skapade regler och antagande för att göra modellen genomförbar, samt de beräkningssteg som utförs. För att kunna skapa modellen har studier om ångnätet utförts på plats och information hämtats ur litteratur.

    Modellens slutprodukt är gjord i Microsoft Excel och använder ett tilläggsprogram PI för att kunna hämta information från fabrikens databas. Ångans eftersökta mängdkostnad redovisas i Excel-dokumentet, i rapporten visas exempel från slutprodukten och redogörs med en förklarande text. Slutprodukten innehar inte bara momentana beräkningar utan erbjuder även förmågan att se över dåtida ångkostnader.

  • 18.
    Owen Berghmark, Victor
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Investeringsunderlag för värmepump: Investeringsunderlag för ett byte från pelletspanna till värmepump i fastighet på södra Gotland2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    One of EU’s climate goals is to reduce the greenhouse gas emissions by 40% by the year of 2030. In Sweden the “building and real estate sector” stands for 21% of Sweden’s total pollution of greenhouse gas emissions. To reach EU’s goals by 2030 there must be a transformation to renewable sources for use in the heating of real estates.

    Region Gotland manages over 500 000 m2 of estates. Many of which uses pellet as the source of heating. This heating alternative requires regular deliveries of material and maintenance. Many of the estates in the care of Region Gotland are far away from both the supplier and maintenance team which creates great transport costs and gas emissions. The fire sta- tion in “Öja” is one of them and is the one used in this study. As there are many similar buildings the results here can be used as a foundation for those estates.

    This study is exploring if a conversion from pellet to a heating pump can lower the expenses and greenhouse gas emissions. By changing to a heat- ing pump from a pellet boiler the temperatures are reduced from 80/60°C to 55/45 °C in the system. This may cause problem with radiators, pumps and pipes. Because of this, radiators and pipes will also be inves- tigated, but pumps will be left out for another study.

    The heat needed to increase the temperature in the building to 21 °C at a DVUT of -8,7 °C was calculated using transmission losses calculations and a formula based on “graddagar” and earlier energy uses by the estate, to 23,8 kW. Based on the calculated heat, three heating pump solutions were created, all of whom included a new water heater with storage tank. The old storage tank is over 40 years by age and therefore has many short- comings.

    Using calculations to optimize the heat usage, the heat needed can be re- duced by 4kW at DVUT by lowering the temperature to 15 °C in the fan heated area of the building while still being within the laws of the Swe- dish work environment authority.

    An investigation was made to see if solar collectors could be used to heat the domestic hot water in the estate. The results showed that in this case

    it wouldn’t be economically justifiable due to low energy cost with a new heating pump.

    The calculations done for pipes and radiators showed that two pipes must be replaced but that the radiators are mostly fine with the new tempera- tures. A replacement of the radiators should be left till after the conver- sion. Calculations on the fan heaters showed that there is no need to re- place these.

    Calculations on greenhouse gas emissions showed that the emissions can be reduce by 2565 kg CO CO2-eq each year if the pellet boiler is replaced by a heating pump.

    The Pay-off method and LCC calculations was used to show the profita- bility in the three heating pump solutions. The Pay-off time for the solu- tions ranged from CTC’s air to water heating pumps at 3,9 years to 4,7 years for Thermia’s geothermal heating pump. The LCC calculations showed that changing to a heat pump could generate a saving of 879 000 SEK for Thermia’s solution to 966 000 SEK for CTC’s solution.

    The conclusion is therefore that the pellet boiler should be changed to a heating pump to save money and reduce the greenhouse gas emissions.

  • 19.
    Parment, Rasmus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    En jämförelsestudie av värmeväxlare: Värmeöverföring för värmeväxlare i korrosiva miljöer2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There are huge gains in both the transport and industry sectors by making material use more efficient in products. This gain is found in both material costs and energy efficiency. Scandymet AB is a company that manufactures heat exchanger and electric immersion heaters for the surface treatment industry. This report aims to evaluate how well a spreadsheet used as basis for the dimensioning of heat exchangers at the company is consistent with reality. A test rig has therefore been designed and constructed to investigate the validity of the spreadsheet. The report presents the results of tests on four different heat exchangers and the results have been compared with the company’s spreadsheet. In all tests water has been used as the media to be heated, but since Scandymet AB’s heat exchanger’s main application is corrosive liquids, therefore I consider that a deeper investigation with additional fluids would be necessary to further deepen the knowledge in the area.

  • 20.
    Rahmström, Marie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Andersson, Kii
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Effektivisering: En utredning om åtgärder på en industrifastighet2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Delta Terminal owns an outdated industrial building which they now rent out to businesses. This property currently has a high energy con-sumption and therfore it is desirable to improve the efficiency. In ordet to reduce the energy consumption within the industrial building enve-lope, the heating systems and lighting are being investegated. A good building envelope emits less heat and thus reduces the energy consump-tion. An energy audit is a tool used to determine the energy loss. A good working environment is essential for customer satisfaction when indus-trial buildings are used as offices. The investigation was carried out through a literature review, oral sources and interviews with tenants. In order to improve the condition of the industrial building from its current situation, a poll based on the View Capture model has been implemented. The model is based on open questions put to the tenants. Worke has been conducted with regards to the problems and sugges-tions for improvement have been developed in appropriate and profita-ble actions. Using regression analysis, the internal rate of return and break-even method has been developed for energy efficiency measures. To implement a new pellet system, a ventilation system and the re-placement of both the lighting and interior windows will provide an industrial building with a more efficient standard. To increase customer satisfaction, new sealing stripes and a refreshment of the common spaces is also recommended. The investigation shows that certain investments meet both energy efficiency and customer satisfaction. The investigation regarding the recommended measures for industrial property was relevant. The objectives of the investigation have been met.

    Keywords: Efficiency, customer satisfaction, energy

  • 21.
    Sheibani, Amjad
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Energieffektivisering och energibalansberäkningar samt förbättrings förslag på nyproducerade lägenheter.2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the work is to investigate real estate climate scale and energy consumption using energy balance calculations. The goal of the report is to disclose how the energy consumption of the building can be described by transmission, air leakage and ventilation calculations. And where you make an energy balance calculations to the real estate. The work delimited to calculate energy balances for a house consisting of 46 apartments and almost all calculations are manual calculations where energy consumption is calculated which gives a good overview of what is needed to improve in apartments. Information about the real estate was collected at a site visit where both inside and outside were investigated as well as conversations with the company PEPA that built the property. A further survey has been made where information about the area, year of construction, previous year's energy declarations and energy calculations was collected, as well as what energy saving measures have been taken today. With the help of literature, web-based sources and articles have been reviewed and processed into a true final result.

    Method: A study of literature research on the subject has been conducted to find relevant and necessary information in the field. To investigate the energy use, heating and construction of the property, several property visits have been made.

    This study has been conducted to investigate investment costs for solar on facades and on roofs of a building. In addition, the study has been conducted to see if these contribute to reducing the property's annual costs and energy consumption over an entire year.

    Results: Transmission losses are 330 MWh and cold bridges”köldbryggor” which are 20% of total transmission losses. While ventilation losses are 270 MWh, where air leakage is 379 W / C. Compilation of U value for transmission losses is 0.35 W/m2.C and energy agency requirements 0.4 W / m2.C, which means that the U value meets the requirements of the building. Heat energy the need for the property is 647 MWh, while the heat power requirement is 228 kW and energy consumption and limit value is 103 kWh / m2, year.

      Discussion: The purpose of the work was to study and look into what energy efficiency measures are available to the house and what measures can provide a good result, to reduce energy consumption and save savings. The survey has been carried out through manual calculations, via talks with HSB staff in place in Östersund and Sundsvall. The survey has also been carried out by collecting all building drawings, through literature and the Boverket, ISO standard and through discussions with companies such as PEAB that have contributed with important information.

    Conclusion: The transmission calculations show that the heat transfer coefficient is a reasonable value, which is a good in comparison with the requirements of 0.4 W / m². K. Furthermore, the report shows that the ventilation used in the property is good when using FTX systems and heat recovery takes place. Another measure calculation performed in the report is a decrease in indoor temperature, which proves to be profitable. The last measure that has been carried out in the report is the fast-moving cranes that show a good deal of savings all year round. Sun cells calculations show two different results the first one sun cells those located on the roof have a life span of 12 years and are more reasonable while the another one those on the facade that have a life span of 30 years.

  • 22.
    Skytt, Torbjörn
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Vakuumteknik med grundläggande termodynamik2007 (ed. 1)Book (Other academic)
    Abstract [sv]

    Vakuumtekniken blir allt vanligare inom industrin. Fler och fler processer har nått den gräns där känsligheten för olika störningar blir allt större. Många produkter som för gemene man kan te sig relativt enkla har en mycket hög teknisk nivå på tillverkningstekniken. Det är lätt att begå misstaget att anse en dator vara mer svårtillverkad än en rulle toapapper, ändå tillverkas det senare i Sverige.

    Vakkumteknik med grundläggande termodynamik syftar till att höja kunskapsnivån för ingenjörer som arbetar med avancerade industriella processer och vill lära sig mer om vakuum. Syftet är att ge en orientering och grund för vidare egna studier och beräkningar inom specifika applikationer.

  • 23.
    Strömsten, Marcus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Förutsättningar för absorptionskyla i Härnösand: En undersökning av tekniken samt en investeringskalkyl2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study examines the absorption cooling technology in order to find the prerequisites of absorption cooling in Härnösand. An investment appraisal has been completed to ensure profitability. Mainly, a literature review has been conducted and the net present value decision rule has been used for the investment appraisal and product specifications have been requested from the main global suppliers. The result shows that there are essentially two absorption chillers commercialized in the market, one of which is applicable for decentralized cooling production in a district heating network at temperatures around 75 °C, and the second which is applicable for temperatures in the range of 120-150 °C and thus not suitable for decentralized cooling production. Research and development for more advanced techniques is ongoing and the investment appraisal shows that the profitability is depending on the size of the chiller unit and the selling price for the cooling energy. The conclusion is that a sale proposal and a motivation are needed on why the customer should choose to have their cooling delivered from an absorption chiller instead of a compressor chiller.

  • 24.
    Topic, Sinisa
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Effektivisering av rökgaskondensorn: En undersökning av att kyla inkommande fjärrvärmeretur2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been executed as an assignment by Sundsvall Energi AB with the purpose of increasing the efficiency of the flue gas condenser by cooling the incoming district heating return before the flue gas condensing exchanger. The flue gas condenser is part of the heat production. The first production unit is the waste boiler where the steam can be distributed between production of electricity and heat production, depending on how large the costumers needs of electricity and heat are. When the customers’ needs are less than Korstaverkets maximum production, an addition of heat from the flue gas condenser means that a larger portion of the steam can go to the turbine and increase the production of electricity. When the customer’s needs are larger than Korstaverkets maximum capacity, a contribution from the flue gas condenser means that Korstaverket can purchase less heat from SCA (Ostrand and Ortviken). The benefit of cooling the district heating return is that more heat and electricity can be produced.

    In the early stages of the project, literature and the Internet were used to get a basic understanding of the assignment. The supervisor and the staff at Korsta have given drawings and data of the power plant process, and also given advice regarding the process. Product data sheets from suppliers have been used for doing calculations and for getting information about the construction. Scientific articles and literature were used to get facts and formulas. The study has shown that the additional cooling of the district heating return has contributed to an increased efficiency of the flue gas condenser, from 0.9 % with an average flow of the deionized water to 17.2 % with a maximum flow of the deionized water. 

    The exam work has shown how complicated an energy system can be. The process can be more complicated then what the drawings show, because a profitable solution in one part of the process can lead to deterioration in another part of the process. The calculations show that the major factor that’s influencing the cooling is the deionized waters flow into the new heat exchanger. The repayment period can get short. High flows generate a profit after only a couple of months, while low flows of 1 liter/second take up to 3.5 years with KE Therms brazed heat exchangers and 2.5 years with Tranters gasketed heat exchangers.

     

  • 25.
    Unger, Oskar
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Fjärrkyla i Sundsvall: Optimering av framledningskurva för akviferbaserad fjärrkyla2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    On behalf of Sundsvall Energi AB, FVB Sverige AB has initiated a preliminary study on the establishment of a district cooling system in Sundsvall. The main source for the cooling will be cool water drawn from the aquifer and a compressor chiller. The main purpose of this project has both been to provide the optimal supply temperature of the cooling network at different outdoor temperatures, and to find out to what extent the cool water from the aquifer can be used by itself as the cooling source. The project was initially focused on examining the climate and cooling demand in Sundsvall. The cooling demand was examined on the basis of six existing buildings that uses freshwater district cooling, and different types of climatesystems were then examined to ascertain what their requirements for the supply temperature are. Cooling coil batteries were found to be the component that requires the lowest supply temperature; therefore, the cooling power calculations were relied on them. The outcome of the cooling coil battery calculations was presumed to correspond to the cooling power of the network itself. By comparing the cooling power of the coil batteries at different supply temperatures and the cooling demand at different outdoor temperatures the main supply temperature for the district cooling network took shape. The aquifer is expected to maintain a temperature of approximately 7°C to 9°C, but in this project the temperature is set to exactly 9°C. On those premises the supply temperature of the cooling network could be set to 11°C for most of the year, but with a reduction of the supply temperature at outdoor temperatures around 21°C. Subsequently the supply temperature is reduced to 6°C at the outdoor temperature 25°C. Via the supply temperature curve, the aquifer cooling coverage ratio could be assessed. The result shows that if the supply temperature is raised between 0,5°C and 1,0°C in the distribution network the compressor chiller will have to be in operation for 159 hours per year. If instead the supply temperature is raised 1,5°C or 2,0°C, the compressor chiller must be in operation for 233 hours and 325 hours, respectively. In summary, all the goals and targets of the project have been completed.

  • 26.
    Vallin, Joel
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Åström, Carl
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Energieffektivisering av Midlanda flygplats: Energikartläggning och energieffektivisering av Midlanda terminalbyggnad2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a C- level Master dissertation focusing on energy efficiency at Sundsvall Timrå airport. The European union and the European parlament, has set a target to reduce energy use by 20 % in the year 2020. The energy used must come from renewable energy sources. Older buildings need energy efficiency, which could mean additional insulation, time-controlled ventilation, replacement of heating systems, windows and lighting. The aim of this study is to develop energy efficiency measures, based on an energy audit of the terminal building envelope. The mapping is done by transmission and ventilation calculations. Additional studies have been done, to see if solar panels can help to meet the hot water requirement, during June, July and August. The report has been implemented through literature studies, contact with staff at Midlanda Airport, site visits, building drawings and documentation from contact Petra Schwartz. Transmission calculations show that the terminal building's floor need additional insulation. An additional insulation of the floor, will lower the airport's heat loss by 13,7 % according to our calculations. Furthermore, the report shows that ventilation can be optimized by upgrading the ventilation system with frequency controlled operation. This results in reduced flow and operating times of the ventilation system, which contributes to reduced energy consumption with 18,5 %. Calculations of a small solar panelsystem, to cover the hot water requirement for the sold heat, during summer shows that this is not economically justifiable. 

  • 27.
    Westerberg, Elin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Sänkt energiförbrukning med byte av energisystem eller energieffektivisering: Ekonomisk analys av fjärrvärme, bergvärme och luft-vatten värmepump i äldre fastigheter kontra energieffektiviseringsåtgärder2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    District heating is the dominant heating method for apartment buildings in Sweden, and its competitor is the heat pumps that have become increasingly efficient and have a better impact on the market. At the same time, the government has set the 2020 targets in order to reduce and improve Sweden's energy use. As the housing sector accounts for almost 40 percent of Sweden's total energy use, the report's purpose is to study how energy consumption for older homes can be reduced by changing energy systems or by maintaining an existing district heating system, but performing energy efficiency measures. The energy systems studied in this report are district heating, geothermal heat and air-water heat pump. The data used in the report has been largely collected from a apartment building located in Vingåker, owned by Sjötorps hus AB. In order for the results to be more general, two example houses have also been studied; A small house and a larger apartment building. The result of the study shows that the biggest cost of district heating is in operation, and thus this option is also the most expensive for the two major houses. However, both investment costs and maintenance costs are significantly higher for heat pumps and vary depending on where in the country they are to be installed, unexpected downtime and breakdowns. The result also shows that it is not profitable for a small house to switch from an existing district heating system to a heat pump. The conclusion is that energy efficiency should be the first option to reduce the energy consumption of a property, especially as the stock of older houses will increase. No matter how little the energy consumption for the newly built houses are, the older houses will be the largest part of Sweden's total housing stock. The fact that the heat pump uses less energy is no long-term solution to energy efficiency. Instead, energy efficiency actions should be the first option when the desire is reduced energy consumption.

  • 28.
    Wickström, Johan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Sänkta ventilationsflöden på Sundsvalls sjukhus: Utvärdering av ett energibesparingsinitiativ genom rökförsök och temperaturmätningar2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With the purpose of lowering energy consumption at Sundsvall Hospital, focus is now being directed towards the ventilation system and the possibility to reduce air flow. The thesis examines this energy-saving initiative by studying what happens to air movements and temperatures in one room at the hospital when ventilation air flow is varied. Air movements were made visible with smoke and observed and temperatures were logged. Observations and data were then analyzed with regard to indoor climate requirements and temperature efficiency, a quantitative measure of how well supplied heat will benefit a room’s occupied zone. The results indicate, among other things, that a too great reduction in air flow rates can have a negative impact on the air quality in the observed room, even though the amount of air supplied is more than sufficient according to current requirements. Best temperature efficiency is achieved when exhaust air passes through both the exhaust air device and the ventilated windows, indicating that this is the most favorable exhaust air setting for lowering ventilation air flow rates or room supply air temperature.

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