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  • 51.
    Karlsson, Mattias
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Malmström, Marcus
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Energibesparande åtgärder i livsmedelsbutiker2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Underlaget till rapporten är att KF fastigheter arbetar aktivt med att minska energiförbrukningen i sina livsmedelsbutiker. För att underlätta beslutstagande och utvärdera olika nyinvesteringar har vi utformat en lathund för energibesparande åtgärder. Lathunden levereras som Excelfiler med förprogrammerade formler.

    Rapporten inriktar sig på kyl- och frysdiskar samt belysning eftersom dessa står för merparten (76 %) av den totala elförbrukningen i en livsmedelsbutik.

    Nyckelord: Energibesparing, Livsmedelsbutik, belysning, ljuskällor, Kyldisk, frysdisk, kylsystem, köldmedier, LCC, pay off, KF-fastigheter, kylsystem, köldmedier, lathund, beräkningsmall.       

  • 52.
    Karlsson, Patrik
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Freidh, Magnus
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Uppföljning av dagvattenmagasin på Lärkgatan i Växjö stad.: Monitoring of storm water management on Lärkgatan in Växjö city.2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Dagvattenmagasin byggs för att fördröja och avlasta ledningssystemet dådagvattenmängderna i dem är stora för att sedan leda tillbaka vattnet i ledningssystemetnär vattenmängderna har sjunkit.

    Examensarbetet syftar till att undersöka och analysera vad som behövs göras för attanvända ett dagvattenmagsinet som är dimensionerat för tioårsregn redan vid femårs- ochtvåårsregn.

    Arbetet grundas på fältstudier och analys av hur systemet är uppbyggt. . Beräkningar hargjorts för studera flöden i ledningar och fyllnadsgrad i magasin. Resultatet visar att det ärmöjligt att med relativt enkla åtgärder kunna utnyttja det aktuella magasinet redan vid 2-och 5-årsregn.

  • 53.
    Karlsson, Stefan
    et al.
    Glafo, Sweden;University of Jena, Germany .
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Limbach, Renè
    University of Jena, Germany.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Wondraczek, Lothar
    University of Jena, Germany.
    Alkali salt vapour deposition and in-line ion exchange on flat glass surfaces2015In: European Journal of Glass Science and Technology. Part A: Glass Technology, ISSN 1753-3546, Vol. 56, no 6, p. 203-213Article in journal (Refereed)
    Abstract [en]

    This study suggests a different route for the modification of flat/float glass surfaces; i.e. exchange of ionic species originatingfrom in-line vapour deposition of salt as compared to the conventional route of immersing the glass in a molten saltbath. The aim of this work is to develop a more flexible and, eventually, more rapid process for improving the mechanicalstrength of flat glass by introducing external material into the surface. We discuss how chemical strengthening can beperformed through the application of potassium chloride on the glass surface by vapour deposition, and in-line thermallyactivated ion exchange. The method presented here has the potential to be up-scaled and to be used in in-line productionin the future, which would make it possible to produce large quantities of chemically strengthened flat glass at aconsiderably lower cost.

  • 54.
    Karlsson, Stefan
    et al.
    Glafo – the Glass Research Institute.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Chemical strengthening of flat glass by vapour deposition and in-line alkali metal ion exchange2014Report (Refereed)
    Abstract [en]

    Glass is a common material in the everyday life. It is widely used in a variety of applications e.g. architectural, automotive, containers, drinking vessels, displays, insulation and optical fibers due to its universal forming ability, transparency, chemical durability, form stability, hardness and relatively low price. Flat glass is a wide market of the glass industry and generally ninety percent of all flat glass produced worldwide is manufactured using the float forming process. There is a large market strive for thinner and stronger glass in order to reduce costs, save energy, reduce environmental footprint, find new applications and to improve the working environment for labour working with mounting flat glass. This study comprises the modification of flat/float glass surface by a novel route; exchange of ionic species originating from in-line vapour deposition of salt compared to the conventional route of immersing the glass in molten salt baths. The aim of this work is to develop a novel process in order to improve the mechanical strength of flat/float glass by introducing external material to the surface in a process with the obvious potential to be automatic in industrial processes. Chemical strengthening has been performed by applying potassium chloride to the glass surface by vapour deposition and thermally activated ion exchange. The method presented here is anticipated to be used in production in the future and would make it possible to produce larger quantities of chemically strengthened flat glass to a considerably lower cost.

  • 55.
    Karlsson, Stefan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Johansson, Marie
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    The effect of single-side ion exchange on the flexural strength of plain and holed float glass containing a drilled hole2013In: European Journal of Glass Science and Technology. Part A: Glass Technology, ISSN 1753-3546, Vol. 54, no 2, p. 66-71Article in journal (Refereed)
    Abstract [en]

    The effect of single-side ion exchange (using a KNO3:KCl mixture) on the ring-on-ring flexural strength of float glass has been studied. Two ion exchanged series, treated at 450 and 515°C, were investigated. The ion exchanged samples showed approximately 160 respectively 100% increases in their arithmetic mean strength compared to as-received float glass. Furthermore, a series of samples containing drilled holes were studied in order to investigate the effect of single-side ion exchange on such common construction elements. The samples that contained drilled holes were ion exchanged at 450°C and showed around 140% increase of the fracture load compared to the untreated samples containing drilled holes. As a general observation, the ion exchange treatment induced ~110 MPa compressive stresses (515°C) and ~180 MPa compressive stresses (450°C). The ion exchanged samples showed no significant increase in stiffness. 

  • 56.
    Karlsson, Stefan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Reibstein, Sindy
    Institute of Glass and Ceramics, Friedrich-Alexander University of Erlangen-Nuremberg.
    Wondraczek, Lothar
    Institute of Glass and Ceramics, Friedrich-Alexander University of Erlangen-Nuremberg.
    Surface ruby colouring of float glass by sodium-copper ion exchange2013In: European Journal of Glass Science and Technology. Part A: Glass Technology, ISSN 1753-3546, Vol. 54, no 3, p. 100-107Article in journal (Refereed)
    Abstract [en]

    In this paper, colouration of the tin side of commercial soda lime silicate float glass by copper ion exchange is described and characterised. Data on the resulting concentration vs. depth profiles, absorbance vs. depth profiles, UV-Vis spectra  and CIE-Lab colour coordinates are reported. Fundamental aspects of the process of colouration are described and discussed. Optimum saturation of colouration is achieved after ion exchange at 520 °C for 10 h, or at 500 °C for 20 h, respectively. The depth of the coloured layer increases with increasing treatment time. At the same time, a linear dependency is found between the value of a and b in the CIE-Lab colour space for variations of treatment time and temperature. The latter indicates broad tunability of colouration between different shades of ruby and varying colour saturation. It is shown that colour arises from a redox reaction between copper species and residual tin ions, and that the depth of the coloured layer is governed by the position of the tin hump. The critical concentration of tin and copper to achieve colour formation was found to be ~0.25 mol% and >1 mol%, respectively.

  • 57.
    Kouhestani, Haidar
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Förbättringsarbete i bygglogistik: En studie i samarbete med Peabs dotterbolag Berg & Väg 2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport presenterar förslag på ständiga förbättringar i form av förändringsförslag och rekommendationer av leveranshantering, samt ordning och reda på arbetsplatsen. Förslag på förändrad bygglogistik har tagits utifrån ett LEANperspektiv.

    Logistik är läran om effektiva flöden, från råvara till slutkonsument. Målet med logistik är att skapa tids- och platsnytta, d.v.s. nyttan för kunden är att produkten befinner sig på en bestämd plats vid en bestämd tidpunkt. Kvalitets- och serviceökning i kombination med lägre kostnader är andra centrala delar inom logistik.

    LEAN production är en företagsfilosofi som anammats av många företag inom tillverkningsindustrin, och som hjälpt dem bli mer produktiva och därmed mer konkurrenskraftiga Områden som kommer att behandlas är leveranshantering, ordning och reda på arbetsplatsen samt ständiga förbättringar i dessa områden.

    Detta arbete genomförs för att effektivisera Berg & Vägs arbetssätt och förbättra ordning och reda ute på arbetsplatsen samt leveranshantering från utlandet. Med ständiga förbättringar menar jag att Berg & Väg måste vara bättre på att ta tillvara på den kompetens som finns inom företaget. De måste också vara bättre på att ta tillvara på de förbättringar som görs och göra en väldig noggrann uppföljning.

    För att utbyte av erfarenheter och ständiga förbättringar skall kunna fungera tror jag att det krävs en enkel och lättförståelig plattform för att kunna sköta detta på ett smidigt sätt. Med effektivisering menas att utforska vad som krävs för att förbättra förmågan att omsätta öppna jämförelser och annan kunskap till ökad effektivitet i praktiken.

    Inledningsvis började jag med att fördjupa mig inom LEAN-filosofin. Jag genomförde även intervjuer och studiebesök. Detta skedde i Stockholm och Växjö. Intervjuer genomfördes med syftet att se dagens rutiner och arbetssätt samt vilka förbättringar de tillfrågade tyckte kunde göras.

    Idag finns det stora oklarheter kring hur leveranser hanteras, och även ordning på arbetsplatsen är i dagsläget lågt prioriterat. En anledning kan vara att personalen inte är medvetna om att det kan leda till tidsslöseri och ökade kostnader.

    Rapportens skallsatser är tänkt att fungera som ett underlag till Berg & Väg. Detta är något som måste följas upp vid varje projekt.

  • 58.
    Lexander, Hampus
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Johansson, Jacob
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Plattgrundläggning enligt Implementeringskommissionen för Europastandarder inom Geoteknik2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den förste januari 2011 blev det obligatoriskt att i Sverige följa dimensioneringsförskrifterna Eurocode 7 vid dimensionering av geokonstruktioner. Eurocode är ett resultatet av det Europeiska standardiseringsorganet CEN’s arbete med att ta fram gemensamma regler för hela Europa.

    Eurocode ersatte BKR som tidigare var de normativa föreskrifterna som gällde i Sverige och med detta skifte startades arbetet med att implementera de nya reglerna fullt ut bland de svenska konstruktörerna.

    På uppdrag av ett lokalt företag har det jämförts och lokaliserat ändringar som gjorts mellan de nya reglerna i bilaga D och de regler som ska appliceras i Sverige. Det har även konstruerats ett beräkningsprogram som dimensionerar grundfundament enligt de nya reglerna som föreskrivs i Eurocode 7, utifrån IEG’s hänvisningar.

    Resultatet från undersökningen visar att de nya dimensioneringsföreskrifterna från EU inte innebar en så stor skillnad från BKR’s regler som först troddes utan den gav stor frihet till att räkna med de metoder som respektive land själva väljer. Vilket Sverige utnyttjade genom att gå tillbaks till de dimensioneringsmetoder som tidigare räknades utifrån, fast med ändring på hur säkerhetsfaktorerna appliceras.

  • 59.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Char conversion kinetics and aerosol characterization in biomass gasification2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biomass gasification is a thermochemical conversion by partial oxidation at elevated temperature of solid biomass into a gaseous energy carrier. The product gas contains the major components CO, H2, CO2, CH4, as well as some tar and inorganic impurities and solid particles such as ash, bed material, soot and char. The aim of this work is to develop an aerosol-based method to investigate on-line the reactivity of the suspended biomass char particles at high temperatures, and to apply aerosol measurement systems for sampling and characterizing particulate matter in the hot product gas from gasifiers.

    An aerosol-based method including the steps for generating, transporting, and oxidizing suspended char particles (0.5–10 µm) was proposed and developed for investigation of char reactivity at high temperatures. An aerodynamic particle sizer (APS) spectrometer was used to measure the particle size distributions. A tapered element oscillating microbalance (TEOM) was used to measure the change of mass concentrations of particles in the carrier gas, before and after conversion. The intrinsic kinetics of various biomass (wood, straw, miscanthus) char particles have been experimentally established in a wide temperature range for both combustion (in air/oxygen) and gasification (in 33 vol% CO2 or 33 vol% steam), up to 800°C and 1300°C, respectively, by combining the aerosol method with thermogravimetric analysis (TGA). The general CO2 or steam gasification reactivity of chars from different biomass could be ranked as wood > miscanthus > straw. In CO2 or steam gasification, the reactivity of char samples measured by the aerosol method at 1300°C would vary by a factor of 4-9 comparing with the extrapolated estimation from the TGA results at the low temperatures. This indicates that high-temperature reactivity estimation by extrapolation should be used with care. Variations of the morphology and the effective density of char particles during conversion indicated that in the initial stage of char conversion (either combustion or gasification), pore growth was dominant up to a certain conversion, and shrinkage or fusing would occur in the later stage. The aerosol-based method presents a set of benefits which are advantageous compared to previously established techniques: no mass transfer limitation at high temperatures; the flexibility to switch to different gas agent combined with continuous feeding of char sample; and the on-line measurement of particle mass and size. The aerosol method is not applicable under the conditions where the reaction rate is slow, since longer residence time will increase the probability of particle losses. In addition to laboratory applications, the aerosol method has potentials for on-line investigation of concentration and reactivity of suspended char fragments sampled directly from the product gas in different types of gasifiers.

    Particulate matter (10 nm–10 µm) in the product gas was characterized for the size distribution, morphology and elemental composition by both on-line and off-line techniques. An aerosol particle measurement system including a dilution probe connected in series with a packed activated carbon bed was applied to extract aerosol from the hot product gas produced in the gasifiers using wood as feedstock: an indirect bubbling fluidized bed gasifier and a circulating fluidized bed (CFB) gasifier. The fine and coarse particles from the CFB gasifier contained calcium and magnesium, indicating the contributions from the ash and the magnesite bed material. From the indirect gasifier, the fine-mode (<0.5 µm) particles were dominated by potassium and chlorine whereas the coarse-mode (>0.5 µm) particles were dominated by calcium and silicon, probably from the ash and the bed material. Char fragments were identified in the hot product gas and contribute to the coarse-mode particles in both gasifiers.

     

  • 60.
    Lin, Leteng
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Further development and application of aerosol-based method for on-line investigation of char reactivity in steam2013In: Proceedings for 21st European Biomass Conference and Exhibition, ETA-Florence Renewable Energies , 2013, p. 875-878Conference paper (Refereed)
    Abstract [en]

    Wood char was prepared from wood pellets under controlled pyrolysis conditions. The gasification kinetics for wood char in 33 vol% steam was established in the temperature range from 800ºC to 1300ºC by the combination of thermogravimetric analysis (TGA) and a novel aerosol-based method. The aerosol method was further developed and demonstrated successfully for generating, transporting and gasifying the suspended char particles (0.5-10 µm) in the steam atmosphere at high temperature up to 1300ºC. A tapered element oscillating microbalance (TEOM) was used to measure the change of mass concentrations of particles in the carrier gas, before and after gasification. The activation energy was 155 kJ·mol-1 for wood char with the pre-exponential factor of 3.56×104. This method can be potentially applied to on-line measure the reactivity of char particles directly in hot gas from the gasifier.

  • 61.
    Lin, Leteng
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Investigation of the intrinsic CO2 gasification kinetics of biomass char at medium to high temperatures2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 109, no SI, p. 220-228Article in journal (Refereed)
    Abstract [en]

    In total eight char samples from pelletized wood, miscanthus, and straw were prepared under various pyrolysis conditions. The CO2 gasification kinetics for each sample was established in the temperature range from 800 °C to 1300 °C by the combination of thermogravimetric analysis (TGA) and a novel aerosol-based method. The aerosol-based method was used for the high temperature range between 1100 °C and 1300 °C, by gasifying suspended char particles (0.5–10 μm) in an oxidizing carrier gas. A tapered element oscillating microbalance (TEOM) was used to measure the change of mass concentrations of particles in the carrier gas, before and after gasification. The results showed that the aerosol-based method could be used to investigate the intrinsic gasification kinetics of biomass char, at least up to 1300 °C. All char samples showed similar reactivity in the low temperature range. However, above 1000 °C there were significant differences in reactivity, and at 1300 °C the conversion of the wood was in the order of 10 times faster than that of straw. The general char reactivity order in this study was wood > miscanthus > straw.

  • 62.
    Lin, Leteng
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Online investigation of steam gasification kinetics of biomass chars up to high temperatures2014In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 28, no 1, p. 607-613Article in journal (Refereed)
    Abstract [en]

    In this study, a novel aerosol-based method has been further developed and applied for on-line investigating of steam gasification kinetics of suspended biomass char particles. By combining the aerosol method with thermogravimetric analysis, the gasification kinetics were established in steam (33 vol%)-N2 atmosphere from 800°C to 1300°C for char samples produced from pelletized wood, straw, and miscanthus. The aerosol method includes steps for generating, suspending, and gasifying char particles. The conversion of the char particles was established by measuring the change in particle size distributions and mass concentrations using an aerodynamic particle sizer (APS) spectrometer and a tapered element oscillating microbalance (TEOM), respectively. The reactivity of three char samples could be ranked as wood > miscanthus > straw. The activation energy was 155 kJ·mol-1 for wood char, 199 kJ·mol-1 for miscanthus char, and 222 kJ·mol-1 for straw char. Results interpreted from TEOM and APS measurements indicated that the effective density of char particles initially decreased until a certain level of conversion was reached, and then remained constant. 

  • 63.
    Lindell, Johan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Muratovic, Armin
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Lögdahl, Per-David
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Vision om en Återbruksby i Växjö2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studiens syfte är att presentera en vision om en återbruksby i form av planskisser och illustrationer. Studien ska också förklara samhällsnyttan och syftet med en återbruksby. En återbruksby (även kallad kretsloppspark) är ett område för hantering av återbrukbara material och produkter. Dagsläget för hur avfall hanteras och framtida planer beskrivs också i rapporten. Enligt EU direktiv skall återanvändning och återbruk öka för att främja miljön.   

    Studien undersöker organisationen Mackens situation och hur deras verksamhet kan bli en återbruksby. Macken vill driva en återbruksby och ska presentera visionen för kommunen i hopp om fortsatt projektering. Visionen innehåller lokaler som alla har koppling till återbruk och förslag på utformning av dessa utifrån olika huskoncept. Som inspiration för områdesplanering används liknande parker.

  • 64.
    Lindskär, Lindskär
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Rydell, Jimmy
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Energikartläggning av tand- och vårdcentralen i Lessebo2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att kunna minska den ständigt ökande energianvändningen i världen så måstebyggnader energieffektiviseras, för att kunna göra en energieffektivisering är ett braverktyg att först göra en energikartläggning. Denna rapport uppskattarenergiförbrukningen såväl som inneklimatet i Lessebos tand- och vårdcentral, byggnadenstod klar i november 2011. Fastighetsägarna vill att fastigheten ska uppnå energistämpelngreenbuilding © , som utlovar en uppvärmning och driftkostnad på högst 75 kWh/m2inklusive fastighetsel, exklusive verksamhetsel. Tillsammans med energikartläggningensom har gjorts genom att mäta och uppskatta varje elektrisk maskins energiförbrukninghar en analys av inneklimatet gjorts. Detta gjordes genom att göra en enkät sompersonalen fick svara på samt mäta sex olika värden i tre av rummen för att teoretisktberäkna missnöjdheten av hur personalen uppfattar inneklimatet. För ett av dessa rum därmätningar inte var möjliga har en simulering över temperaturen för sommaren gjorts.Den totala värme- och fastighetselförbrukningen mellan sista augusti 2012 till sistaaugusti 2013 uppskattas till 69 kWh/m2. Därmed uppnår byggnaden de krav som ställs föratt byggnaden ska få energistämpeln greenbuilding. Totala elanvändningen för fastighetenär 18 % lägre än den genomsnittsliga vårdlokalen enligt energimyndighetens granskningöver vårdlokaler 2007. Enligt en modell/simulering så borde 66 % av personalen varamissnöjda med personalrummet (1037) vintertid, vilket stämmer bra överens medenkätsvaren som säger att 65 % är missnöjda

  • 65.
    Mahapatra, Krushna
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Energy renovation of single-family houses: importance of economic aspects and suggested policymeasures2013In: eceee 2013 Summer Study proceedings: Rethink, renew, restart, European Council for an Energy Efficient Economy (ECEEE), 2013, p. 529-536Conference paper (Refereed)
    Abstract [en]

    In Sweden, more than 80% of the single-family houses are more than 30 years old and majority of them need some renovation. This provides opportunities for implementation of energy efficiency measures, which depends on homeowners’ adoption-decision. Results from several surveys by us showed that more than 80% of the Swedish homeowners consider annual energy cost and investment cost to be the two most important factors in the choice of energy efficiency measures. They preferred investment subsidies and tax deduction on energy efficiency measures, but did not like energy and carbon taxes on energy use. We discuss marketing and policy measures to overcome various obstacles to energy renovation of detached houses. A marketing measure is to introduce one-stop-shop business models where a single actor offers all types of services, including financing, required to undertake energy renovations. A national goal for energy efficiency improvements in existing buildings coupled with a list of actions needed to achieve that goal and tailored incentives will help to establish a market for energy renovations. For an owner of detached house, the goal could be set by energy-certificate, and then one-stop-shop service would provide the plan and actions needed to reach the goal.

  • 66.
    Mahapatra, Krushna
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Haavik, Trond
    Segel As, Norway.
    Aabrekk, Synnøve
    Segel As, Norway.
    Svendsen, Svend
    Technical University of Denmark, Lyngby, Denmark.
    Vanhoutteghem, Lies
    Technical University of Denmark, Lyngby, Denmark.
    Paiho, Satu
    VTT, Finland.
    Ala-Juusela, Mia
    VTT, Finland.
    Business models for full service energy renovation of single family houses in Nordic countries2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 112, p. 1558-1565Article in journal (Refereed)
    Abstract [en]

    In Nordic countries significant primary energy saving potential exists in houses built before 1980. These old houses need to be renovated, which provides an opportunity for implementation of energy efficiency measures. However, there are several economic and market hindrances and the renovation markets are dominated by handicraft-based individual solutions. In this paper we have analyzed the opportunities for implementation of one-stop-shop business models where an overall contractor offers full-service renovation packages including consulting, independent energy audit, renovation work, follow-up (independent quality control and commissioning) and financing. A comparative assessment of emerging business models in the Nordic countries shows that different types of actors can provide such a service. Financing is included in some models. There are differences in how customers are contacted, while the similarities are on how the service is provided. Even though there is strong business potential for one-stop-shop energy renovation concept, still it has been somewhat difficult to start or run such a business. Various options to overcome the hindrances to promote energy efficient renovation of detached houses are discussed.

  • 67.
    Mahapatra, Krushna
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Olsson, Stefan
    Energy Agency for Southeast Sweden, Växjö.
    Energy performance of two multi-storey wood-frame passive houses in Sweden2015In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 5, p. 1207-1220Article in journal (Refereed)
    Abstract [en]

    Two eight-story wood-framed residential buildings with the Swedish 2012passive house standard were built in 2009 in the Portvakten Söder quarter in the city of Växjöin Sweden. In this paper, we present the monitored specific energy use of the buildings andcompare to the requirements of the Swedish building code and recommendation for passivehouses. We also estimated the primary energy use and CO2 emissions and investigated thetenants’ views and experiences of the two buildings. Results show that the actual specificenergy use of 40.2 kWh/m2Atemp/year in the Portvakten Söder building fulfills, by a goodmargin, the requirements of the Swedish building code and the recommended passive housestandard, but is higher than projected. Applying a marginal perspective, the calculatedprimary energy use and carbon dioxide emission from operating the buildings (excludinghousehold electricity) was 40 kWh/m2Atemp/year and zero, respectively. Responses of 20 tenantsto a mail-in questionnaire survey showed that over 90% were satisfied with their apartments.

  • 68.
    Milesson, Joel
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Abrahamsson, Erika
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Geoenergilager Xylem: Visualisering och lönsamhet2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inom svensk process- och tillverkningsindustri finns det stora mängder spillvärme som sällan kommer till användning. Att hitta olika tekniska lösningar för att effektivt tillvarata denna spillvärme skapar både nytta ur ett hållbart perspektiv samt ur ett ekonomiskt perspektiv för företaget.

    I denna rapport presenteras en utarbetad beräkningsmodell i Excel. Beräkningsmodellen används för att uppskatta lönsamheten för anläggning av ett högtemperaturlager i berggrunden. Excel-filen ska kunna användas för företag som en första uppskattning om ett borrhålslager är ett alternativ för tillvaratagande av spillvärme. Utformningen av beräkningsmallen utgick från Xylems högtemperaturlager i Emmaboda.

    Beräkningsmallen testades på Xylems borrhålslager. Resultatet visar att 2166 MWh/år kan tas ut från lagret, vilket stämmer överens till 83 % med Xylems egna beräkningar. Borrhålslagrets verkningsgrad beräknades till 65 % vilket kan jämföras med de 68 % som Xylem kalkylerat med.

    Nyckelord: Borrhålslager, UTES-system, BTES-system, HT-BTES-system, geoenergi, spillvärme.

  • 69.
    Nilsson, Martin
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strömberg, Erik
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Parkett eller plastmatta, spelar det roll?2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    IKEAs mål är att deras produkter ska vara för ”de många människorna”. För att bygga hus som passar ihop med detta måste det vara till kostnader som folk har råd med.

    Syftet med den här rapporten är att ta fram ett förslag på en yteffektiv lägenhet som kan sättas ihop till ett mindre flerbostadshus. Yteffektiva lägenheter gör att huset tar upp mindre plats på marken och därför kostar mindre per kvadratmeter. Med hjälp av detta hus kommer en jämförelse av kostnader för olika invändiga ytmaterial att utföras. Detta kommer användas för att se hur stor skillnad det blir på slutsumman om man till exempel väljer ”finare” ytmaterial, som parkett och klinker, istället för plastmatta.

  • 70.
    Olsson, Anders
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Källsner, Bo
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Oscarsson, Jan
    SP Sveriges Tekniska Forskningsinstitut.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Nytt paradigm för hållfasthetssortering av konstruktionsvirke: Projektrapport ett2013Report (Other academic)
    Abstract [sv]

    Den undersökning som redovisas i denna rapport har genomförts under hösten 2012 och våren 2013 inom projektet "Nytt paradigm för hållfasthetssortering av konstruktionsvirke". Projektet som kommer att pågå under perioden december 2011 till juni 2014 går ut på att för industriellt bruk utveckla en nyligen föreslagen metod för hållfasthetssortering av konstruktionsvirke, vilken baseras på laserskanning i kombination med dynamisk excitering och densitetsbestämning av virke. Projektet finansieras till 50 % av VINNOVA och till 50 % av de företag som medverkar i projektet, nämligen Innovativ Vision AB (IV), Vida Vislanda AB, Södra Timber AB, Derome Timber AB och Dynalyse AB. Linnéuniversitetet (Lnu) och SP Sveriges Tekniska Forskningsinstitut AB (SP) samverkar med nämnda företag i utförandet av forskningen.

    Syftet med undersökningen är i först hand att utvärdera alternativa sätt för att bestämma densitet för virke och att verifiera implementeringen av programvara för industriellt bruk. Syftet är också att ta fram ett utökat material för att bedöma vilken precision den nya sorteringsmetoden kan erbjuda och för att bedöma hur känslig den är för olika typer förändringar och störningar som kan uppkomma. Undersökningen bygger på ett begränsat material och en mer omfattande undersökning planeras för genomförande under senare delar av projektet.

  • 71.
    Olsson, Anders
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Oscarsson, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology. SP Technical Research Institute of Sweden.
    Serrano, Erik
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Källsner, Bo
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Johansson, Marie
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Prediction of timber bending strength and in-member cross-sectional stiffness vartiation on basis of local wood fibre orientation2013In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 71, no 3, p. 319-333Article in journal (Refereed)
    Abstract [en]

    Machine strength grading of structural timber is based upon relationships between so called indicating properties (IPs) and bending strength. However, such relationships applied on the market today are rather poor. In this paper, new IPs and a new grading method resulting in more precise strength predictions are presented. The local fibre orientation on face and edge surfaces of wooden boards was identified using high resolution laser scanning. In combination with knowledge regarding basic wood material properties for each investigated board, the grain angle information enabled a calculation of the variation of the local MOE in the longitudinal direction of the boards. By integration over cross-sections along the board, an edgewise bending stiffness profile and a longitudinal stiffness profile, respectively, were calculated. A new IP was defined as the lowest bending stiffness determined along the board. For a sample of 105 boards of Norway spruce of dimension 45 × 145 × 3600 mm, a coefficient of determination as high as 0.68-0.71 was achieved between this new IP and bending strength. For the same sample, the coefficient of determination between global MOE, based on the first longitudinal resonance frequency and the board density, and strength was only 0.59. Furthermore, it is shown that improved accuracy when determining the stiffness profiles of boards will lead to even better predictions of bending strength. The results thus motivate both an industrial implementation of the suggested method and further research aiming at more accurately determined board stiffness profiles.

  • 72.
    Olsson, Caroline
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Kulturhistorisk inventering av bebyggelse och miljö för områdena Stensberg och Rönnäs i Ljungby stad2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Idag saknas en bra översikt för kulturhistoriskt intressanta byggnader i hela Ljungby stad. Centrumbebyggelsen är inventerad och värderad sedan tidigare, men övriga delar av staden är i behov av samma arbete.  Målet är att denna studie ska leverera ett kunskapsunderlag som underlättar vid planering och bygglovsprövning. I arbetet inventeras och värderas bebyggelsen och miljön i områdena Stensberg och Rönnäs i Ljungby stad.  

    Genom fältobservationer och studier av bl.a. kartor och ritningar har konstaterats att bebyggelsen är av varierande karaktär. Den har tillkommit under olika decennier och har därför många olika stilar. På områdena finns det mestadels bostadshus i form av villor, men det finns också flerfamiljshus samt offentliga byggnader som en skola, en restaurang och en kyrka. Förslag på utökat skydd för ett antal byggnader och bebyggelsemiljöer har tagits fram.

  • 73.
    Olsson, Morgan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Robert, Åkesson
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Energieffektivisering av prefabricerade byggelement2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten behandlar energieffektivisering av Villa Vidas prefabricerade byggelement. I arbetet undersöks hur och med hjälp av vilka material en effektivisering av elementen kan gå till. I slutet av rapporten presenteras sedan det förslag till varje väggtyp som bedömdes som lämpligast att ersätta respektive standardalternativ med.

  • 74.
    Olsson, Victor
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Brodin, Ken
    Ombyggnad av Osby Kommunhus till bostäder2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Osby kommun ska flytta sin verksamhet till en ny byggnad. Ett förslag som diskuterats är att det nuvarande kommunhuset ska byggas om till bostäder.

    Runt om i Sverige ökar den äldre befolkningen vilket den även gör i Osby kommun. Det gör att bostäderna måste vara tillgänglighetsanpassade vilket kräver noggrann projektering. I detta arbete kommer förslagen beroende på målgrupp vara tillgänglighetsanpassade.

    Två förslag presenteras där det ena är bostäder med loftgång och det andra ett trygghetsboende med ett befintligt samt nytt trapphus, för att möta en äldre målgrupp. I båda utformningsförslagen har fokus även lagts på att få bort kontorskänslan.

  • 75.
    Oscarsson, Jan
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Olsson, Anders
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Determination of tensile strain fields in narrow Norway spruce side boards as a basis for verification of new machine strength grading methodsManuscript (preprint) (Other academic)
    Abstract [en]

    Today’s methods for machine strength grading of structural timber result, in general, in strength predictions with a rather low accuracy. A need for development of more precise methods has been identified. Application of stiffness in terms of locally determined MOE as indicating property is an evident starting point for such a process. Development of new grading procedures and models require laboratory verification, and this research investigates the possibility of using contact-free deformation measurement technique based on white-light digital image correlation (DIC) for this purpose. A sample of nine Norway spruce (Picea abies) side boards of narrow dimensions was tested in tension according to the European Standard EN 408. Simultaneously, deformations along the entire length of one of the flatwise surfaces of each board were measured using two master-slave connected DIC systems. Strain fields were subsequently calculated. To evaluate the accuracy of the measurement technique, local MOE determined traditionally, i.e. on the basis of elongations measured in accordance with EN 408, was compared with corresponding MOE values calculated on the basis of DIC deformation measurements. Acceptable agreement between compared MOEs were achieved and the accuracy of MOE values determined on the basis of the DIC technique was on the same level as requirements laid down in EN 408. However, the resolution of the information supplied by the DIC technique can, in contrast to elongations measured traditionally, be used to gain detailed knowledge regarding local MOE in evaluated boards. Therefore, based upon achieved results, in combination with certain identified potentials for measurement improvements, it is concluded that DIC technique can be used as a tool for development and laboratory verification of new strength grading methods.

  • 76.
    Oscarsson, Jan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology. SP Technical Research Institute of Sweden.
    Olsson, Anders
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Optimization of machine strength grading of structural timber by means of bending MOE profiles with high resolution2013In: Proceedings of the 18th International Nondestructive Testing and Evaluation of Wood Symposium, Madison, Wisconsin, USA, September 24−27, 2013, Madison: USDA (United States Department of Agriculture), Forest Service, Forest Products Laboratory , 2013, p. 396-403Conference paper (Refereed)
    Abstract [en]

    Most machine strength grading methods are based on rather poor statistical relationships between edgewise bending strength and modulus of elasticity (MOE), the latter determined either as flatwise bending MOE measured over a length of about one meter, or as global axial dynamic MOE. Furthermore, European Standards stipulate that local MOE in both edgewise bending and tension shall be determined at a critical section and over a length of five times the depth of the piece. However, a study of tensile strain fields determined on side board surfaces using contact-free measurement technique showed that stiffness reduction occurs very locally. This characteristic was used for development of a new indicating property (IP) defined as local edgewise bending MOE and determined by means of scanned fibre direction fields and stiffness integration over cross-sections. A maximum coefficient of determination equal to 0.77 was obtained between strength and such an IP determined over a length of about the member’s half depth.

  • 77.
    Parsland, Charlotte
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Nickel-substituted Ba-hexaaluminates as catalysts stem-reforming of tars2013In: CRS-2, Catalysis for Renewable sources: Fuel. Energy, Chemicals Book of Abstracts / [ed] Vadim Yakovlev, Boreskov Institute of Catalysis, Novosibirsk: Boreskov Institute of Catalysis , 2013, p. 62-63Conference paper (Refereed)
    Abstract [en]

    Gasification of woody biomass converts the solid organic material into a gaseous product with a higher energy value and by this mean provide a more carbon neutral gaseous fuel than the common fossil ones. The produced raw gas mainly contains H2, CO, CO2, CH4, H2O and N2 together with organic (tars) and inorganic (alkali) components and fine particulates. The amount of impurities in the raw gas is dependent of the fuel properties and the gasification process technology and the quality of the resulting product gas determines its suitability for more advanced purposes. One of the major general concerns within the gasification processes is the formation of tars. Tars are a vast group of polyaromatic hydrocarbons and there are a number of definitions. On an EU/IEA/US-DOE discussion meeting in Brussels 1998, a number of experts agreed on a simplified classification of tars as “all organic contaminants with a molecular weight larger than benzene” [1]. The aim of this work is to investigate the steam reforming ability of a catalytic material not previously tested in this type of application in order to achieve an energy-efficient and high-quality gasification gas. The physical demands for an optimal tar-cracking and steam reforming catalyst is a high surface area, thermal stability, mechanical strength and a capacity to withstand high gas velocities, poisons such as H2S or NH3 and other impurities. Additionally it has to resist the process steam, as steam is well known to enhance sintering of porous materials. Nickel is a familiar catalyst for steam reforming. Hexaaluminate is a well-known catalyst support with properties that may answer to the requests of a non-abrasive, high-temperaturestable and steam-resistant catalytic material. It is a structural oxide where the general formula for the doped unit cell is MIMII(x)Al12-xO19-d where MI represents the mirror plane cation and MII is the aluminum site in the lattice where substitution may occur. MII is often a transition metal ion of the same size and charge as aluminum. MI is an ion located in the mirror plane of the structure and it is a large metal ion, often from the alkaline, alkaline earth or rare earth metal group. The stability and activity of these materials are often being related to the properties of MI and MII. The activity is highly dependent on the nature of the Al-substituted metal and partially by the nature of MII [2]. In our experiments we have tested the catalytic capacity of Ni-substituted Ba-hexaaluminates synthesised by the sol-gel method [3], both in a model set-up and in a gasification plant. In the lab-scale set-up different catalyst-formulae was tested under various temperatures for reforming of methyl-naphthalene. The results show a good catalytic activity for tar-breakdown. As expected the substitution level of Ni is clearly coupled to the reaction temperature. With the most highly substituted Ni-Bahexaaluminate at 900 °C all of the methyl-naphthalene has been broken downtogether with all of the resulting hydrocarbons. The Ni-Bahexaaluminate catalyst has recently also been tested in real process-gas.

    These results are still to be evaluated, but indicate a positive result.

     

     

  • 78.
    Phung, Kent
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Chu, Charles
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Adhesives for Load-Bearing Timber-Glass Elements: Elastic, plastic and time dependent properties2013Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work is part of an on-going project regarding load-bearing timber glass composites within the EU program WoodWisdom-Net. One major scope of that project is the adhesive material between the glass and timber parts. The underlying importance of the bonding material is related to the transfer of stress between the two materials – the influence of the adhesive stiffness and ductility on the possibility of obtaining uniform stress distributions. In this study the mechanical properties of two different adhesives are investigated, an epoxy (3M DP490) and an acrylate (SikaFast 5215). The differences of the adhesives lay in dissimilar stiffness, strength and viscous behaviour. In long term load caring design is important to understand the materials behavior under a constant load and a permanent displacement within the structure can cause major consequences. Therefore the main aim in this project is to identify the adhesives strength, deformation capacity and possible viscous (time dependent) effects. Because of the limitation of equipment and time this study is restricted to only three different experiments. Three different types of tensile tests have been conducted: monotonic, cyclic relaxation tests.The results of the experiments show that 3M DP490 has a higher strength and a smaller deformation capacity as compared to the SikaFast 5215. Thus, the SikaFast 5215 is more ductile. The 3M DP490 exhibits a lower loss of strength under constant strain (at relaxation). SikaFast 5215 showed also a large dependency of strain level on the stress loss in relaxation.

  • 79.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Sefidari, Hamid
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Characterization of hot gas in a 4 MW reciprocating grate boiler2014In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 124, p. 21-27Article in journal (Refereed)
    Abstract [en]

    The gas concentration and temperature information from the combustion of biomass offer significant advantages to enhance the understanding of an industrial-scale biomass heating plant. The main objective of this study was to investigate the gas composition and temperature in a 4 MW reciprocating grate boiler. An extensive series of measurements was carried out, and the samples, which were drawn through different ports by means of a water-cooled stainless steel suction pyrometer, were analyzed for temperature and for O2, CO, and NO concentrations. The results showed that the averaged NO, CO, and O2 concentrations in the gas phase during fuel combustion in the primary chamber were 40 ppm, 3.5 and 6.5 vol.%, respectively, while the values were 80 ppm, 1.1 and 6 vol.% in the secondary chamber. Detailed gas species and temperature distributions are discussed, which provide good possibilities for the control of emissions.

  • 80.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Sefidari, Hamid
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Yang, Jingjing
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gas measurements and characterization of wood combustion in a traveling grate boiler2013In: Proceedings for 21st European Biomass Conference and Exhibition, ETA-Florence Renewable Energies , 2013, p. 591-594Conference paper (Refereed)
    Abstract [en]

    Experimental tests have been carried out on a moving grate boiler at a 4 MW heating plant located at a sawing mill in south of Sweden. In order to investigate the performance of the combustion chamber, the local concentrations of O2, NO and CO are determined in the region above the grate using two water-cooled stainless steel probes of different lengths and diameters. The fuel used was sawmill waste consisting of bark, sawdust and shavings. The results of the study provided valuable insights into the combustion process.

  • 81.
    Risén, Emma
    et al.
    Kungliga Tekniska Högskolan.
    Gregeby, Erik
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Tartarchenko, Olena
    Kungliga Tekniska Högskolan.
    Blidberg, Eva
    Kungliga Tekniska Högskolan.
    Malmström, Maria
    Kungliga Tekniska Högskolan.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gröndahl, Fredrik
    Kungliga Tekniska Högskolan.
    Assessment of biomethane production from maritime common reed2013In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 53, p. 186-194Article in journal (Refereed)
    Abstract [en]

    Several ongoing projects are harvesting maritime biomass from the Baltic Sea for eutrophication mitigation and utilisation of the recovered biomass. Some of this biomass comprises common reed (Phragmites australis), one of the most widespread vascular plants on Earth. Reed utilisation from eutrophied coastal areas needs to be evaluated. Therefore, a system analysis was performed of reed harvesting for biofuel and biofertiliser production. The specific objectives of the analysis were to: investigate the methane yield associated with anaerobic co-digestion of reed; make a primary energy assessment of the system; quantify Greenhouse Gas (GHG) savings when a fossil reference system is replaced; and estimate the nutrient recycling potential of the system. The results from energy and GHG calculations are highly dependent on conditions such as system boundaries, system design, allocation methods and selected indicators. Therefore a pilot project taking place in Kalmar County, Sweden, was used as a case study system. Laboratory experiments using continuously stirred tank reactor digesters indicated an increased methane yield of about 220 m3 CH4/t volatile solids from co-digestion of reed. The energy balance for the case study system was positive, with energy requirements amounting to about 40% of the energy content in the biomethane produced and with the non-renewable energy input comprising about 50% of the total energy requirements of the system. The net energy value proved to be equivalent to about 40 L of petrol/t reed wet weight. The potential to save GHG emissions compared with a fossil reference system was considerable (about 80%). Furthermore an estimated 60% of the nitrogen and almost all the phosphorus in the biomass could be re-circulated to arable land as biofertiliser. Considering the combined benefits from all factors investigated in this study, harvesting of common reed from coastal zones has the potential to be beneficial, assuming an appropriate system design, and is worthy of further investigations regarding other sustainability aspects.

  • 82.
    Runesson, Lars
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Potential för solcellsanvändning i Karlskrona2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport ska verka till Karlskrona kommuns kvantifiering av potentialen för solcellsanvändning. Med litterära studier och fallstudieunderlag så har en modell för att beräkna möjligt solenergiupptag samt livscykelkostnader utformats. Med modellen som underlag och i samråd med SMHI så har Karlskronas möjliga solenergiupptag beräknats till ca 1100 kWh/(m2*år) för en horisontell yta. Med en verkningsgrad hos kristallina kiselbaserade solcellsmoduler på 15 % så skulle det därmed behövas en yta av ca 370 ha för att täcka Karlskrona kommuns elbehov. Livscykelkostnaden med solcellsmodulerna kan enligt fallstudierna till mer än 90 % kopplas till anskaffning. Fallstudierna över den senast uppförda solcellsanläggningen anger en energikostnad på 2,09 kr/kWh vid en uppskattad livstid på 25 år. Dock ingår inte kostnaden för avveckling vid dessa beräkningar vilket gör livscykelkostnaden ofullständig.

  • 83.
    Said, Marcel
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology. Växjö.
    Ohlsson, Mattias
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Bestämning av metanpotential hos blåmusslor och nötgödsel2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Kraftig övergödning i Östersjön leder till ökad blomning av alger som medför

    syrebrist i havet. Musselodling kan ses som en åtgärd för problemet. På den svenska

    östkusten beräknas skördningen av musslor vara på ca 65 000 ton/år.

    Rötningsförsöket av blåmusslorna skedde i en pilotanläggning på Linnéuniversitet

    som består utav en lakbädd och en UASB-reaktor (Upflow Anaerobic Sludge

    Blanket), där syrabildningen sker i lakbädden och metanbildningen i UASB.

    Musslorna gav ett metanutbyte på 0,32 m

    3/(kg VS) för hela rötningsperioden.

    Ensy AB specialiserar sig på att producera koncentrerad växtnäring från gödsel. De

    har som planer att utveckla sin verksamhet för att samköra produktion av biogas från

    gödsel. Gödslet som erhölls från Ensy AB rötades i ett satsvist försök i nio behållare

    med 100g/behållare. Rötningen av gödslet gav ett metanutbyte av 0,073 m3/(kg*VS).

    Försöket visar att det finns potential att använda blåmusslor som resurs för

    biogasproduktion. Genom utnyttjandet av musslor och gödsel som biogassubstrat kan

    övergödningen minskas, dessutom minskar utsläppet av metangas.

  • 84.
    Salomonsson, Joakim
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Detaljplanerad materiallogistik för byggarbetsplatser med hög upprepandegrad2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det råder bostadsbrist i Växjö men det byggs trots detta väldigt få nya hyreslägenheter. Ett sätt att möjliggöra byggandet av fler hyresrätter är att finna besparande lösningar under produktionsskedet som på så sätt kan få ner byggkostnaderna och öka intresset hos bostadsbolagen att bygga nytt.

    Denna rapport fokuserar på de kostnader som rör materialhanteringen på produktionsplatser med hög upprepandegrad. Syftet är att belysa var onödiga kostnader uppstår och försöka finna lösningar på hur dessa kan undvikas.

    Nyckelord: Materialhantering, materiallogistik, hög upprepandegrad, hanteringskostnader, intervju, tidstudie, förändringsförslag.

  • 85.
    Sathre, Roger
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Haus, Sylvia
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Time Dynamics and Radiative Forcing of Forest Bioenergy Systems2013In: Forest BioEnergy Production: Management, Carbon Sequestration and Adaptation, Springer, 2013, p. 185-206Chapter in book (Refereed)
    Abstract [en]

    In this chapter we explore the temporal dynamics of using forest bioenergy to mitigate climate change. We consider such issues as: growth dynamics of forests under different management regimes; the substitution effects of different bioenergy and biomaterial uses; temporary carbon storage in harvested biomass; the availability of different biomass fractions at different points of a wood product life cycle; and changes in carbon content of forest soils. We introduce the metric of radiative forcing, which quantifies the accumulating energy due to the global greenhouse effect, and we describe a method to estimate quantitatively and to compare the cumulative radiative forcing (CRF) of forest bioenergy systems and reference fossil energy systems. In three case studies, we describe the time dynamics and estimate the CRF profiles of various forest biomass systems.

  • 86.
    Stepinac, Mislav
    et al.
    Univ Zagreb, Croatia.
    Hunger, Frank
    Tech Univ Munich, Germany.
    Tomasi, Roberto
    Univ Trent, Italy.
    Serrano, Erik
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Rajcic, Vlatka
    Univ Zagreb, Croatia.
    van de Kuilen, Jan-Willem
    Tech Univ Munich, Germany.
    Comparison of design rules for glued-in rods and design rule proposal for implementation in European standards2013In: PROCEEDINGS OF THE CIB - W18: WORKING COMMISSION W18 - TIMBER STRUCTURES / [ed] Gorlacher, R, 2013, p. 87-99Conference paper (Refereed)
  • 87.
    Sterley, Magdalena
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Serrano, Erik
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Enquist, Bertil
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Fracture characterisation of green glued-polyurethane adhesive bonds in Mode I2013In: Materials and Structures, ISSN 1359-5997, E-ISSN 1871-6873, Vol. 46, no 3, p. 421-434Article in journal (Refereed)
    Abstract [en]

    Unseasoned (green) spruce timber side boards of size 25 × 120 × 600 mm were flatwise-glued with a one-component PUR adhesive. Glued pairs of boards were then kiln-dried to 12 % moisture content. A special small-scale specimen for testing the fracture properties of the adhesive bond in Mode I was developed in order to evaluate the adhesive bond properties. The complete force versus deformation curve, including both the ascending and the descending parts, could be obtained with these small-scale specimens, enabling the strength and fracture energy of the bond line to be calculated. In addition, the fractured specimens were examined by scanning electron microscope. Results show that both the tensile strength and the fracture energy of the green glued PUR adhesive bonds were equal to those of the dry glued bonds. The methodology developed and used in the present study gives new possibilities for analysis of the mechanical behaviour of wood adhesive bonds, and particularly of their brittleness and its correlation with the type of fracture path. This is in sharp contrast to the use of standardised test methods (e.g. EN 302, ASTM D905) with specimens having relatively large glued areas. Using such types of specimens, it is not possible to obtain the complete force versus deformation response of the bond. In addition, when using such test methods, failure takes place in the wood or in the fibres near the bond, thus making it impossible to obtain detailed information about the bond line characteristics.

  • 88.
    Svensson, Helena
    et al.
    Chemical Engineering, Lund University.
    Tunå, Per
    Chemical Engineering, Lund University.
    Hulteberg, Christian
    Chemical Engineering, Lund University.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Modeling of soot formation during partial oxidation of producer gas2013In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 106, p. 271-278Article in journal (Refereed)
    Abstract [en]

    Soot formation in a reverse-flow partial-oxidation reactor for reforming of gasifier producer gas has been studied. The process was modeled using a detailed reaction mechanism to describe the kinetics of soot formation. The numerical model was validated against experimental data from the literature and showed good agreement with reported data. Nine cases with different gas compositions were simulated in order to study the effects of water, hydrogen and methane content of the gas. The CO and CO2 contents, as well as the tar content of the gas, were also varied to study their effects on soot formation. The results showed that the steam and hydrogen content of the inlet gas had less impact on the soot formation than expected, while the methane content greatly influenced the soot formation. Increasing the CO2 content of the gas reduced the amount of soot formed and gave a higher energy efficiency and methane conversion. In the case of no tar in the incoming gas the soot formation was significantly reduced. It can be concluded that removing the tar in an energy efficient way, prior to the partial oxidation reactor, will greatly reduce the amount of soot formed. Further investigation of tar reduction is needed and experimental research into this process is ongoing.

  • 89.
    Sällström, David
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Persson, André
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Den teoretiska energiåtgången: Två energiberäkningar av Blåsbälgen2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Arbetet är utfört åt VVS-Byrån i Växjö AB för att visa hur en mer noggrann energiberäkning påverkar den teoretiska energianvändningen jämfört med en tidigare gjord energiberäkning.

    Genom att samla ihop olika arkitekt- och konstruktionsritningar har vi med hjälp av programmet VIP-Energy konstruerat ett så sanningsenligt klimatskal som möjligt. Programmet har även bearbetat rekommenderad indata från Svebyprogrammet, Boverkets byggregler och SMHI, samt indata av olika byggnadsinstallationer.

    Resultatet visar att skillnader i verksamhetsenergi till rumsluft, externfastighetsenergi och tappvarmvatten har störst inverkan på energiåtgången. Beräkningarna visar också att det fall där köldbryggor är modellerade i 2D ger en teoretisk energiåtgång som liknar de uppmätta värdena mer än det fall då köldbryggorna läggs in som ett 20 % påslag gentemot ett första Um-värde.

  • 90.
    Thuvesson, Paul
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Johnsson, Daniel
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Emilsson, Andreas
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Världsarvet rasar: Visby ringmur och liknande försvarsanläggningar2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En del av Visby ringmur rasade i februari 2012. Detta examensarbete tar upp ringmurens konstruktion och lösningar på hur man skall kunna återuppbygga muren på ett kulturhistoriskt korrekt sätt. Rapporten tar även upp andra murkonstruktioner och lösningar som man har använt sig av på liknande murar runt om i Europa. För att beskriva olika lösningar som förklarar hur försvarsmurar är uppbyggda och som kan ge inspiration till lösningar i uppbyggnaden av Visby ringmur. Liknande konstruktioner och murverk som har studerats närmare är Eketorp, Gråborg, Torsburgen, Roms stadsmur, Tallinns stadsmur och Kronobergs slottsruin.

  • 91.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    District heat production under different environmental and social cost scenarios2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    District heat production systems (DHSs) are normally designed to meet the heat demand of customers at a minimum cost whilst fulfilling local and national regulations. Various factors influence the choice of district heat production units in a minimum-cost system. In this thesis, the performance of DHSs of different types were analyzed under a range of environmental and social cost scenarios. The scenarios include No tax using the bare cost of fuels without any taxes or fees, Swedish tax using Swedish taxes and fees on fuels, Social cost-550ppm using a carbon damage cost of US$30/t CO2, Social cost-BAU using a carbon damage cost of US$85/t CO2, and Renewable-based without using fossil fuels for energy purposes. DHSs were analyzed under varying conditions of scale, potential to co/poly-generate district heat with other products, and integration of new technologies currently being developed. The influence of end-use energy efficiency measures in district-heated buildings on DHSs was also analyzed.

    The cost optimal composition of a DHS depends on several factors including the scale, the load factor of the heat demand, the technologies used in the DHS, as well as the environmental and social costs. When environmental and social costs are considered, the co-generation of electricity is more cost-efficient than other options, except for small scale systems, for which heat-only production is more cost-efficient. Also, in a minimum-cost DHS, district heat production cost is about the same for all the environmental and social cost scenarios except for the No tax scenario. The district heat production cost of a small-scale DHS under the No tax scenario is lower than that of the same scale system under the other scenarios. However, a large-scale DHS under the No tax scenario gives higher district heat production cost than the same scale system under the other scenarios. The changed environmental and social costs vary the types and amount of fuel use as well as the value of co-generated products such as electricity, which consequently balances the district heat production cost.

    Renewable-based DHS using biomass is economically viable if environmental and social costs of using fossil fuels are taken into account. A fully biomass-based DHS can be as primary energy-efficient as other DHSs analyzed. Typically, biomass-based co-generation of district heat and electricity combined with stand-alone production of biomotor fuels is more cost- and primary energy-efficient than the co-generation of district heat and biomotor fuels combined with stand-alone production of electricity. The integration of non-fuel renewable technologies such as solar water heating can further reduce the use of biomass in a cost-efficient way for small-scale DHSs in combination with high fuel costs.

    The characteristics of a DHS influence the effectiveness of end-use energy efficiency measures in district heated buildings. Although end-use energy efficiency measures change the final energy use, the composition and operation of the supply system determine the amount and types of fuel savings. Supply systems with different composition and operation give varying primary energy savings per unit of reduced end-use energy from an energy efficiency measure. The primary energy savings due to end-use heat saving measures in buildings is much higher for heat-only production units than for co/poly-generation units, because heat savings in co/poly-generation systems also reduce the potential production of co-products. Therefore, the analysis of both demand and supply sides of district heating systems as well as their interaction is crucial for the evaluation of the consequences of end-use energy efficiency measures in district-heated buildings. Actually, energy efficiency measures in district-heated buildings typically increase the overall heat load factor for a DHS which reduces the operating cost per unit of produced district heat in existing system and the total cost when existing district heat production units have to be renewed or changed. The connection of new energy-efficient buildings that balances the energy efficiency improvement in existing district-heated buildings appears to be an optimal option for a DHS.

  • 92.
    Truong, Nguyen Le
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Dodoo, Ambrose
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Effects of energy-efficiency measures and climate change mitigation policy instruments on primary energy use in district-heated buildings2013In: ECEEE Summer Study proceedings: rethink, renew, restart, European Council for an Energy Efficient Economy (ECEEE), 2013, p. 515-522Conference paper (Refereed)
    Abstract [en]

    The effectiveness of energy-efficiency measures in a district-heated building can be complex, as it depends on how energy is produced and used. In this study, a primary energy analysis was conducted based on a case study of a Swedish apartment building that is connected to a district heat production system while considering different climate change mitigation policy instruments including carbon taxes corresponding to Social cost-Business-as-usual or Social cost-550 ppm scenarios. The potential to reduce final heat and electricity demands by different energy-efficiency measures was analyzed for the building used in the case study. The impacts of reducing final energy from the different energy-efficiency measures and the climate change policy instruments on primary energy use and cost of district heat production were investigated using a systems analysis approach. We discussed the importance of analyzing the demand and supply sides and their interaction to minimize primary energy use in district-heated buildings. We showed that climate change mitigation policy instruments have a minimal effect on heat production costs for optimally designed district heat production. The primary energy savings for the energy-efficiency measures depend partly on the characteristics of the district heat production system, which is influenced by the policy instruments.

  • 93.
    Truong, Nguyen Le
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Dodoo, Ambrose
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Effects of heat and electricity saving measures in district-heated multistory residential buildings2014In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 118, p. 57-67Article in journal (Refereed)
    Abstract [en]

    The effects of heat and electricity saving measures in district-heated buildings can be complex because these depend not only on how energy is used on the demand side but also on how energy is provided from the supply side. In this study, we analyze the effects of heat and electricity saving measures in multistory concrete-framed and wood-framed versions of an existing district-heated building and examine the impacts of the reduced energy demand on different district heat (DH) production configurations. The energy saving measures considered are for domestic hot water reduction, building thermal envelope improvement, ventilation heat recovery (VHR), and household electricity savings. Our analysis is based on a measured heat load profile of an existing DH production system in Växjö, Sweden. Based on the measured heat load profile, we model three minimum-cost DH production system using plausible environmental and socio-political scenarios. Then, we investigate the primary energy implications of the energy saving measures applied to the two versions of the existing building, taking into account the changed DH demand, changed cogenerated electricity, and changed electricity use due to heat and electricity saving measures. Our results show that the difference between the final and primary energy savings of the concrete-framed and wood-framed versions of the case-study building is minor. The primary energy efficiency of the energy saving measures depends on the type of measure and on the composition of the DH production system. Of the various energy saving measures explored, electricity savings give the highest primary energy savings for the building versions. In contrast to the other heat savings measures, VHR gives lower primary energy savings as it also increases electricity demand. Primary energy savings for the building versions are lower where the minimum-cost DH production system includes cogeneration unit compared to where the minimum-cost DH production system comprises heat-only boilers. The primary energy savings are mainly from peak and medium-load boilers even though these production units cover a small share of the total DH production. This study shows that it is essential to consider the interaction between end-use energy saving measures and supply systems for district-heated buildings, to estimate the primary energy efficiency of energy saving measures.

  • 94.
    Truong, Nguyen Le
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Integrated biomass-based production of district heat, electricity, motor fuels and pellets of different scales2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 104, p. 623-632Article in journal (Refereed)
    Abstract [en]

    Woody biomass can be used in different ways to contribute to sustainable development. In this paper, we analyze biomass-based production of district heat, electricity, pellets and motor fuels. We calculate production cost and biomass use of products from standalone production and from different district heat production options, including only heat production and various co/polygeneration options. We optimize the different district heat production systems considering the value of co/polygenerated products, other than district heat, as equal to those produced in minimum-cost standalone plants. Also, we investigate how the scale of district heating systems influences the minimum-cost composition of production units and district heat production costs. We find that co/polygenerated district heat is more cost and fuel efficient than that from heat-only production. Also, coproduction of electricity is more efficient than of motor fuels except for dimethyl-ether production in large district heat production systems. However, the cost difference is minor between coproduction of dimethyl-ether or electricity in such systems. Integrated biopellet production increases the production of electricity or motor fuel and reduces the production cost. District heat production cost depends on fuel price, however, its dependence is reduced if district heat production system is cost-minimized and based on co/polygenerated units. Also, the optimal composition and cost of district heat production depend on the scale of the system. The demand for biopellets may limit the potential integrated production of such a product. (C) 2012 Elsevier Ltd. All rights reserved.

  • 95.
    Truong, Nguyen Le
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Minimum-cost district heat production systems of different sizes under different taxation schemes2013In: International Conference on Applied Energy, July 1-4, 2013, Pretoria, 2013Conference paper (Refereed)
  • 96.
    Tuna, Per
    et al.
    Lund University.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Selective catalytic oxidation of ammonia by nitrogen oxides in a model synthesis gas2013In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 105, p. 331-337Article in journal (Refereed)
    Abstract [en]

    Synthesis gas generated by the gasification of nitrogen-containing hydrocarbons will contain ammonia. This is a catalyst poison and elevated levels of nitrogen oxides (NOX) will be produced if the synthesis gas is combusted. This paper presents a study of the selective oxidation of ammonia in reducing environments. The concept is the same as in traditional selective catalytic reduction, where NOX are removed from flue gas by reaction with injected ammonia over a catalyst. Here, a new concept for the removal of ammonia is demonstrated by reaction with injected NOX over a catalyst. The experiments were carried out in a model synthesis gas consisting of CO, CO2, H-2, N-2 and NH3/NOX. The performance of two catalysts, V2O5/WO3/TiO2 and H-mordenite, were evaluated. On-site generation of NOX by nitric acid decomposition was also investigated and tested. The results show good conversion of ammonia under the conditions studied for both catalysts, and with on-site generated NOX. (C) 2012 Elsevier Ltd. All rights reserved.

  • 97.
    Valtersson, Johanna
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Värmeförluster från kulvertar2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I den har rapporten kartläggs och bedöms omfattningen av värmeförluster från kulvertar i Landstinget Kronobergs sekundära fjärrvärmenät på Sigfridsområdet. Teoretiska stationära värmeförlustberäkningar har utförts med Petter Wallenténs samband från 1991 samt med det via internet tillgängliga beräkningsprogrammet Logstor Calculator 2.1.

    Beräkningar över energibesparingen vid ett byte av de äldsta kulvertarna i det sekundära nätet till nya kulvertar visar att tvillingkulvertar i isolerklass 2 är att föredra framför enkelrör både i isolerklass 2 såväl som 3.

    Rapporten behandlar miljöaspekter kring fjärrvärme samt möjligheter och konsekvenser kring en energieffektivisering av distributionen genom sänkta systemtemperaturer.

  • 98.
    Waldén, Erik
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Nyberg, Dennis
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Utvärdering av kulvertförluster: En fallstudie utförd på AB Ronnebyhus2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today’s society is facing several challenges. The population is increasing and an improved living standards leads to increased energy consumption. Of the total energy consumption in Sweden, construction consumes about 40 %.In 1999 the Government set future goals for energy consumption in Sweden. It shall be reduced with 20 % by 2020 and with 50 % by 2050 for residential and commercial building with the reference year 1995.AB Ronnebyhus wanted to get a better overview of their use of heat and how much they lost. Therefore heat meters were installed at various point of measurement, recording data continuously. A significant heat loss was discovered.The purpose of the study is to provide a basis for how much temperature and heat losses occurs in the buried culvert pipes between the buildings in the residential area Tallen.The basic idea of the study was that the heat losses occurred due to inadequate culvert pipes because we believed they were outdated. In early stages we found out that the pipes were from 2006 and considerably newer than expected. This means that the existing culvert pipes have good standards and other factors had to be considered. Instead, focus was on the flow adjustment of the heating system and to examine the temperature of the incoming and outgoing water.Using flow adjustment protocols, calculations and measurements we discovered the heat system is not optimally adjusted and the heat losses from the system is significant.

  • 99.
    Wigermo, Mikael
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Norlander, Lucas
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    En lokals energibehov: Jämförelse och modellering av olika typer av klimatsystem 2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis focused on compiling a calculation model suitable for calculating an indoor climate system energy demand and life cycle cost, LCC. The model was created in Excell and uses given input data to calculate the results.

    The model was used to compare four different premises located in buildings owned by VIDEUM AB in Växjö. Two offices and two lecture halls was compared. The calculated differences in energy demand could be derived to longer operating times during weekends for one system. One office had a large constant air flow even during absence which also led to a greater energy demand.

    Whether the system was regulated by using carbon dioxide concentrations or temperature as indicators on air quality didn’t seem to affect the energy demand significantly. Unnecessary high flow rates and operating times affects the premises energy demand the more.

  • 100.
    Wimmer, Rupert
    et al.
    Univ Bodenkultur Wien BOKU.
    Johansson, Marie
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Effects of Reaction Wood on the Performance of Wood and Wood-Based Products2014In: The Biology of Reaction Wood / [ed] Gardiner, B., Barnett, J., Saranpää, P., Gril, J., Springer, 2014, 1, p. 225-248Chapter in book (Refereed)
    Abstract [en]

    Compression wood in softwoods and tension wood in hardwoods have properties, which adversely affect its usefulness for wood products. This chapter shows that reaction wood can be associated with many unsuitable wood properties. The results vary due to the fact that definitions about occurrence and severity of reaction wood are scarcely documented. A few properties seem to be even benefitting from the presence of reaction wood: the higher smoothness of compression wood surfaces, better shear strength of compression wood, higher toughness and impact resistance when tension wood is present, lower water uptake and swelling in fibreboards containing compression wood, and higher durability against fungi of compression wood. However, these are outweighed by disadvantages, which is the reason why reaction wood has a bad reputation in industry. The problem with reaction wood is that it is in most cases mixed with normal wood, which leads to non-uniform and more variable properties. This may lead to non-uniform swelling and shrinking, causing distortions, with additional problems of reduced strength and unfavourable surface properties. Wood-based materials such as particle boards or fibreboards are generally less prone to problems associated with reaction wood than solid wood products. With knowledge-based production methods the utilization of different wood types, including reaction wood, might be feasible.

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