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  • 1001.
    Tillman, Joacim
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Kategorisering av byggnader i Gävles fjärrvärmenät utifrån dess effektsignaturer: En fallstudie2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Gävle Energi have recently implemented a new price model for district heating with a seasonal depended price model that came in 2018 and a capacity pricing model that will be implemented 2019. The new price model is supposed to reflect the cost to produce the district heating and to reward customers who preform efficiency measures to their buildings. The capacity pricing model, on which this study is focused on, will be based on the buildings energy demand at -10 degrees. Since the capacity price is the same for all customers, the price the customer pays instead will reflect the amount of energy demand the building needs at -10 degrees. In this study it will be investigated whether an estimate can be made to find out how big of an energy demand a newly connected customer’s building needs at -10 degrees from previously connected customers. Signatures from 115 previously connected customers with buildings build from 2000 – 2018 were used in this study. The building was then categorized to compare the energy demand for each customer with a similar building. Based on this, signatures were created for each individual building and then put together in a common chart for each category. With this, the idea was that a standard signature could be created for each category to the use this signature when calculating the capacity for a customer’s building. As the result was not as intended, these standard signatures could not be created without preforming a deeper analysis of each building. If a standard signature had been created with these results, an unfair capacity had been awarded to customers with a high and low energy consumption. Different analyzes were used to calculate the different energy demands for the creation of the signatures, partly with the housing area of the buildings and the surrounding area with the thoughts that the surrounding area would provide the study with a better result. However, the use of the surrounding area in the development of the signatures did not provide to be of better use as the results varied too much.

  • 1002.
    Toledo Monfort, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering. daniel.toledomonfort@gmail.com.
    ECONOMIC AND ENERGETIC ASPECTS TO CONSIDER IN WINDOW RENOVATION ALTERNATIVES: A case study in a cold climate2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When thinking of renovating the windows of old buildings, the building owner has a lot of decisions to make. These are to keep the window but make it more energy efficient by adding an extra pane or to completely change the whole window. At the same time, the joint between the window frame and wall makes a thermal bridge which depends on how much insulation has been placed in the cavities after installation. Upon the decision of keeping the window, the status of this joint will be unchanged. This thesis deals with finding out the best economical solution for a company that has rental apartments in Gävle in Sweden, Gavlegårdarna AB. To calculate the thermal bridges, which are weak areas of the building envelope in which they significantly increase the energy load of houses, a CDF program called Fluent is used to quantify the heat loss at the joints. Measurements have been performed to validate the CFD model. To simulate the energy savings in the building, the building energy simulation program IDA-ICE is used. Finally, Life Cycle Costing calculations are made to assess the best long term economical option. It is concluded that the most reasonable solution is to add an extra glass in the existing window, but it is not the most ecofriendly. A more ecological solution is to add the extra glass and to perform enhanced insulation at the joints around the window frames and walls, or to replace the old window with a new low energy window – however, these are not profitable so

  • 1003.
    Torlén, Anton
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Industrial design.
    What to Make of Waste: Material Driven Design for Better Palm Oil Practices2018Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Palm oil production create a number of solid biomass waste products, in particular empty fruit bunches and mesocarp fiber; two cellulosic plant materials that are under-utilized and a source of environmental pollution today. Their fibred structure are interesting from an industrial design perspective as similar waste products from industrialized crops are used to create composite materials.

    This bachelor thesis is based on an initial research phase of the palm oil industry in Thailand, where literary studies, case-studies and interviews were used to gain understanding of how the palm oil industry in Thailand operates. This laid the foundation to a material driven design process; an exploratory phase where samples of waste products collected during the research phase were tinkered with, to create composite materials of natural fibers and starch-based plastics.

    The materials created were characterized by their technical properties, and evaluated through a focus group of Thai students to define their experiential characteristics. The insights learned from the evaluation were used to create a demonstrative concept of how the material can be put to future use.

    The experiential characterization showed that the material have valuable sensorial, performative, emotional and interpretive properties, such as strength, flexibility and translucency, while being perceived as elegant, amusing, strange and natural. This leads to the conclusion that there is possible added value in the waste products that are seen as a nuisance today.

    Parallel to the material driven design process, samples of empty fruit bunches and mesocarp fiber were used to develop a 3D-printing filament. While only simple test prints have been tried at the time of writing, it provides proof of concept.

  • 1004.
    Torrent Lluch, Mariona
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Ground heat pump in combination with district heating for a multi-dwelling building in Gävle2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Environment has become a major concern for society, which awareness of the importance of an environmentally respectful development has been growing during the last decades. Economic reasons have encompassed this transition to a more planet friendly conception of human development. In fact, this transition has been parallel to the growing prices of fossil fuels, facing a clear perspective of a shortage on its availability, insufficient to cope with a growing demand in the near future. Within this context, the role of renewable energies in order to stop depending on fossil fuels and to reduce greenhouse gases emissions has become crucial.

     

    Because of its climate, heating represents a major source of energy consumption in Sweden, accounting for almost 60% of the residential and services sector energy use. Maximizing the efficiency of heating systems and using renewable, environmentally friendly and economically sustainable sources of energy may have an enormous impact on both environment and economy.

     

    In this thesis the use of district heating and ground heat pump for a multi-dwelling building is evaluated, both from the economic and environmental points of view. Both are recognized to be efficient heating systems, allowing important savings of other sources of energy, and respectful with the environment.

     

    An installation combining both district heating and ground heat pump, for a multi-dwelling building in Gävle has been analyzed. Different scenarios have been considered, and results obtained show that when installing a ground heat pump, both economic savings and CO2 emissions reduction are obtained. Annual economic savings account for 16,8% when providing 60% of the thermal energy with the ground heat pump, and considering the investment associated to the recent installation of a new heat pump (in the case studied, boreholes were already drilled), the payback time is 7,4 years. CO2 emissions reduction for a normal year reaches 34%. However, if we look at the wider picture of electricity and heat production from a community (local, regional, national or even international) point of view, several considerations have to be taken into account, which are discussed in the report.

  • 1005.
    Torres, João Paulo N.
    et al.
    Instituto de Telecomunicações, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.
    Fernandes, Carlos A. F.
    Instituto de Telecomunicações, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.
    Gomes, João
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Luc, Bonfiglio
    Ecole Polytechnique Universitaire de Montpellier, Montpellier, France.
    Carine, Giovinazzo
    Ecole Polytechnique Universitaire de Montpellier, Montpellier, France.
    Olsson, Olle
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Branco, P. J. Costa
    Associated Laboratory for Energy, Transports and Aeronautics, Institute of Mechanical Engineering (LAETA, IDMEC), Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.
    Effect of reflector geometry in the annual received radiation of low concentration photovoltaic systems2018In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 11, no 7, article id 1878Article in journal (Refereed)
    Abstract [en]

    Solar concentrator photovoltaic collectors are able to deliver energy at higher temperatures for the same irradiances, since they are related to smaller areas for which heat losses occur. However, to ensure the system reliability, adequate collector geometry and appropriate choice of the materials used in these systems will be crucial. The present work focuses on the re-design of the Concentrating Photovoltaic system (C-PV) collector reflector presently manufactured by the company Solarus, together with an analysis based on the annual assessment of the solar irradiance in the collector. An open-source ray tracing code (Soltrace) is used to accomplish the modelling of optical systems in concentrating solar power applications. Symmetric parabolic reflector configurations are seen to improve the PV system performance when compared to the conventional structures currently used by Solarus. The parabolic geometries, using either symmetrically or asymmetrically placed receivers inside the collector, accomplished both the performance and cost-effectiveness goals: for almost the same area or costs, the new proposals for the PV system may be in some cases 70% more effective as far as energy output is concerned.

  • 1006.
    Torres, João Paulo N.
    et al.
    University of Lisbon, Lisbon, Portugal.
    Nashih, Samuel K.
    University of Lisbon, Lisbon, Portugal.
    Fernandes, Carlos A. F.
    University of Lisbon, Lisbon, Portugal.
    Leite, João C.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    The effect of shading on photovoltaic solar panels2018In: Energy Systems, Springer Verlag, ISSN 1868-3967, E-ISSN 1868-3975, Vol. 9, no 1, p. 195-208Article in journal (Refereed)
    Abstract [en]

    A modelling description of photovoltaic (PV) modules in a PSPICE environment is presented. To validate the simulation model, a lab prototype is used to create similar conditions as those existing in real photovoltaic systems. The effects of partial shading of solar cell strings and temperature on the performance of various PV modules are analyzed. The simulation results show a very good agreement with those obtained experimentally in similar conditions, either in lab, at Lisbon University, and under outdoor testing in Sweden, using PV solar collectors manufactured by Solarus Sunpower AB. The potential of the simulation analysis is highlighted as a flexible and powerful tool for the design of new and more competitive PV module configurations for the collectors in solar panels.

  • 1007.
    Twumasi Afriyie, Ebenezer
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Norberg, Peter
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Sjöström, Christer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Forslund, Mikael
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Preparation and characterization of double metal-silica sorbent for gas filtration2013In: Adsorption, ISSN 0929-5607, E-ISSN 1572-8757, Vol. 19, no 1, p. 49-61Article in journal (Refereed)
    Abstract [en]

    This paper presents the preparation of a porous (Mg, Ca) silicate structure, which could be employed as sorbent filter media. The sorbents have been prepared using sodium silicate precipitated with various ratios of magnesium and calcium salts. The sorbents obtained were characterized using scanning electron microscope (SEM), X-ray diffraction (XRD) and nitrogen physisorption isotherm. Further, the applicability and performance of the sorbent impregnate with potassium hydroxide for removal of sulphur dioxide (SO2) has been demonstrated. From the isotherms, specific surface area, pore diameter and volume of pores were estimated. Results show that the chemical composition and textural properties of the resultant sorbents were highly dependent on Mg/Ca molar ratio. It was found that sorbents made with 68 mol% Mg and 32 mol% Ca (PSS-MgCa-68/32); and 75 mol% Mg and 25 mol% Ca (PSS-MgCa-75/25) exhibited even higher specific surface area and pore volume than the sorbents containing a single metal. The Mg/Ca-silica sorbents obtained contains interconnected bimodal porosity with large portions being mesopores of varied sizes. The pore size distribution (PSD) results further indicate that PSS-MgCa-68/32 sorbent exhibits wide PSD of interconnected pores in the size range of 1 to 32 nm while PSS-MgCa-50/50 and PSS-MgCa-75/25 exhibits narrow PSD of 1 to 5 nm. Using SO2 as model contaminate gas, it was shown that the dynamic adsorption performance of the PSS-MgCa-sorbents impregnated with 8 wt% KOH exhibits SO2 uptake, with impregnated PSS-MgCa-68/32 showing better performance. This shows that the materials prepared can be used as adsorbent for gas filtration.

  • 1008.
    Twumasi Afriyie, Ebenezer
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Norberg, Peter
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Sjöström, Christer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Forslund, Mikael
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Textural and hydrogen sulphide adsorption behaviour of double metal-silca modified with potassium permanganate2013In: Journal of porous materials, ISSN 1380-2224, E-ISSN 1573-4854, Vol. 20, no 3, p. 447-455Article in journal (Refereed)
    Abstract [en]

    A new MgCa–silica material with bimodal pore size is impregnated with KMnO4 for dynamic adsorption of H2S. The MgCa–silica was synthesized using sodium silicate and calcium and magnesium salts as precipitating agents. The KMnO4 impregnation onto MgCa–silica was obtained through either direct addition into MgCa–silica wet coagulum or doping of dried MgCa–silica pellets into KMnO4 solution. These chemisorbents were characterized by nitrogen physisorption, spectrophotometer, microscopy and dynamic H2S adsorption test setup similar to ASHRAE standard I45.I. The results show that impregnation route and KMnO4 wt% cause a reduction of surface area and total pore volume. The decrease in pore volume was slightly more in chemisorbents obtained via post doping compared to direct impregnation. Regardless of pore volume reduction the pore size range, 1–32 nm, was as in the parent MgCa–silica with micro and meso-pore diameter centered at 1.4 and 5.4 nm respectively. Thus obtained chemisorbents have their pore entrances neither blocked nor shifted. The MgCa–silica/KMnO4 chemisorbents exhibits good H2S uptake performance. The chemisorbent with 11.4 wt% KMnO4 and obtained via direct impregnation possesses the highest uptake capacity. The lowest capacity was observed for chemisorbent with 8 wt% KMnO4 and made by direct impregnation. The variations in uptake capacity are likely due to impregnation route, the KMnO4 content and its location in the pore system. The results suggest that the MgCa–silica/KMnO4chemisorbents can remove H2S from indoor air at room temperature.

  • 1009.
    Twumasi, Ebenezer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Byggnadsmaterial.
    Molecular filtration: the study of adsorbents2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Adsorbent materials for gas purification have been studied and developed for application in many areas. It is known that a single adsorbent may not adequately control multiple contaminants. Therefore, the development of adsorbent materials has accelerated over the past two decades, and is today an area attracting a lot of attention. In view of the global environmental movement for clean air, the development of improved sorbents will help address new challenges that cannot efficiently be met with the generic sorbents that are presently commercially available. On the other hand, the utilization of these new sorbents for specific applications within the area of molecular filtration remains largely unexplored. This thesis presents a synthesis of new sorbent materials, and the characterization and application of these materials for molecular filtration. Commercial adsorbents have been used for benchmarking for the pore properties, the applicability, and the performance of these new adsorbents. A double metal-silica adsorbent has been synthesized. The preparation procedure is based on the use of sodium silicate coagulated with various ratios of magnesium and calcium salts which yields micro-meso porous structures in the resulting material. The results show that molar ratios of Mg/Ca influence the pore parameters as well as the structure and morphology. The bimodal pore size can be tailored by controlling the Mg/Ca ratio. The effect of thermal treatment on pore parameters of these adsorbents has been investigated. The results show that heat treatment had a notable effect on the pore parameters, and that the pore structure was thermally stable even at 600°C.

     A synthesis method has also been developed for the preparation of carbon-silica composites. The method involves a number of routes, which can be summarised as addition of activated carbon particles to (I) the paste, (II) the salt solution, or (III) with the sodium silicate solution. In route II and III the activated carbon is present also before coagulation. The routes presented here leads to carbon-silica composites possessing high micro porosity, meso porosity as well as large surface areas. The increase in micro porosity and surface areas was linear with carbon content. The results shows further that pore size distribution may be tailored based on the route of addition of the carbon particles. Following route I and III a wide pore size (1-30nm) was obtained where as by route II a narrow pore size (1-4nm) was observed. KOH or KMnO4 modified MgCa adsorbent varieties were also prepared. The impregnationwas performed by either a direct synthesis or post-synthesis procedure. Potassium hydroxide and potassium permanganate have been chosen as impregnate chemicals. Results revealed that theimpregnate amount significantly affected both the structural and the gas adsorption characteristics of the impregnated MgCa adsorbents. The properties of double- metal adsorbents, impregnated adsorbents and carbon-silica composites were characterized by various methods (X-ray diffraction, scanning electron microscopy, thermo gravimetric analysis, and nitrogen adsorption at 77K) to study the material structure and morphology, thermal stability, ignition temperature and porous parameters with regard to surface area, pore size, pore size distribution and porosity volume, which is important for optimizing their use in many practical application. The up-take performance of adsorbents for dynamic adsorption of SO2, H2S and toluene was performed in a system similar to the setup usedin ASHRAE 145.1. Finally the applicability and performance of the impregnated modified MgCa-silica adsorbents and composites have been evaluated for H2S, SO2 and toluene adsorption and compared to some commercial adsorbent materials. Results revealed that a potassium permanganate modified MgCa-adsorbent has a H2S adsorption capacity in the range of 0.08-3.19 wt % at 50% efficiency, and that the uptake capacity was relative to the amount of potassiumpermanganate loading. Moreover, KOH modified MgCa-adsorbent shows highest SO2 adsorption capacity (1.7 wt %) which is 3.47 times higher than commercial alumina impregnate with potassium permanganate (0.49 wt %). Carbon-silica composites on the other hand shows adsorption of toluene and high adsorption capacity was obtained when carbon content was 45 wt %. The results further shows that a composite with 45 wt % carbon and obtained via route I present the highest toluene adsorption capacity ( 27.6 wt % relative to carbon content) at 0% efficiency. The large uptake capacity of this composite was attributed to the presence of high microporosity volume and a wide (1-30nm) bimodal pore system consisting of extensive mesopore channels (2-30nm) as well as large surface area. These capacity values of carbon-silica composites are competitive to results obtained for commercial coconut based carbon (31 wt %), and better than commercial alumina-carbon composite.

  • 1010.
    Twumasi, Ebenezer
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Forslund, Mikael
    Norberg, Peter
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Sjöström, Christer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Textural and adsorption properties of a carbon-silica composite adsorbent for air filtration2010In: World Journal of Engineering, ISSN 1708-5284, Vol. 7, no 2, p. 227-228Article in journal (Other academic)
  • 1011.
    Twumasi, Ebenezer
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Norberg, Peter
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Forslund, Mikael
    Materials Technology KTH Reserch School.
    Sjöström, Christer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Carbon–silica composites prepared by the precipitation method: Effect of the synthesis parameters on textural characteristics and toluene dynamic adsorption2012In: Journal of porous materials, ISSN 1380-2224, E-ISSN 1573-4854, Vol. 19, no 3, p. 333-343Article in journal (Refereed)
    Abstract [en]

    Three synthesis routes are presented here that leads to carbon–silica composites. These were characterized by nitrogen physisorption, by thermogravimetric analysis and by dynamic toluene adsorption test similar to Ashrae standard I45.1. The carbon–silica composites possess high microporosity and mesoporosity as well as large surface areas. Furthermore, the control of the microporosity as well as pore size distribution is possible because they depend on the amount of carbon used and of the synthesis route. Following routes I and III a wide micro-mesoporous pore size (1–32 nm) was obtained where as by route II narrow micro-mesoporous pore size (1–4 nm) was observed. In addition, pore diameters center in the range of 1.13–1.17 nm was observed when carbon content was 32 or 45 wt%. The dynamic adsorption of toluene was evaluated for carbon–silica composites obtained by three preparation routes at two different carbon contents, 32 and 45 wt%. The results showed that a composite with 45 wt% carbon content and obtained via preparation route I gave the highest toluene adsorption capacity (27.6 wt% relative to carbon content). The large uptake capacity of this composite was attributed to the presence of high microporosity volume and a wide (1–32 nm) bimodal pore system consisting of extensive mesopore channels (2–32 nm) as well as large surface area. These capacity values of carbon–silica composites are by weight relative to carbon content and are competitive to, results obtained for commercial coconut activated carbon (31.1 wt%) and significantly better than a commercial alumina-carbon composite(9.5 wt%) at 0% efficiency.

  • 1012.
    Twumasi, Ebenezer
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Norberg, Peter
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Sjöström, Christer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Buildning science - material science.
    Tailored Precipitated Silica Adsorbents for the Built Environment2011In: XII DBMC: 12th International Conference on Durability of Building Materials and Components (Vol. 4): Michael A. Lacasse, Vasco Peixoto de Freitas, Helena Corvacho, Porto: FEUP Edições , 2011, , p. 8Conference paper (Refereed)
    Abstract [en]

    The paper provides a review of the synthesis and adsorptive properties of a novel class of precipitated silica materials. To enhance or tailor the adsorption efficiency, various trapping chemicals (potassium hydroxide, potassium permanganate) or co-adsorbents (coconut activated carbon) are incorporated in the structure of the substrate material. Further, it discusses the applicability and performance over time of the material as adsorbents for removal of hydrogen sulphide, sulphur dioxide and toluene contaminants which are potentially hazardous to sensitive equipment and more importantly, human health. Chemical substances in the air are an unavoidable by-product of most human endeavours within industry and transportation. The need for adsorbents to combat Airborne Molecular Contamination (AMC) follows from the continued intensification of the global environmental movement as well as the rapid industrialisation of developing countries. The removal performance of modified precipitated silica adsorbent shows that the new adsorbent can be tailored to remove low concentrations of sulphur dioxide, hydrogen sulphide and toluene contaminants at indoor environment conditions. The results further shows that the new precipitated silica adsorbent impregnated with 8 wt% KOH shows better performance than commercial alumina impregnated with 8 wt% KMnO4.The adsorbent material may find interesting and efficient uses as passive sinks for pollutants incorporated into more traditional building products such as acoustic baffles or as ingredients in various coatings. The filter material is environmentally friendly and consists of benign chemicals that are abundant worldwide. Performance over time aspects, re-use and recycling of exhausted filter materials are key issues addressed.

  • 1013.
    Tärnåsen, Jim
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Framtagning av beräkningsprogram för helsvetsade balk-balkinfästningar i stål: Verifiering genom fullskalig belastningsprovning2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 1014.
    Udd, Maria
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Industrial design.
    Stämningsskapande ljus: Ett designkoncept med fokus på ljusets stämningsskapande funktion.2017Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
  • 1015.
    Uppenberg, Caroline
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Blod, svett och smärta: Innovativa handskydd2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Träningshysterin är på sin topp just nu. Idag är träning någonting många prioriterar för att må bra. Av intensivt fysiskt arbete, som till exempel hård styrketräning eller crossfit får man snabbt valkar och sår i händerna. Det finns en uppsjö av handskar designade för olika typer av träning på marknaden, trots detta används handskarna inte alls av många. Orsaken är dels att handskydd har fått en stämpel som ”fånigt” i träningssamanhang och dels upplevs handskar som ett hinder snarare än ett skyddsmedel. Detta eftersom gymhandskar upplevs klumpiga och försämrar greppet. 

    Begreppet design handlar inte endast om utseende och estetik, utan innefattar även funktionalitet. God design är när man uppfyller ett behov hos användarna både vad gäller utseende och funktion. Genom ett antal kvantitativa intervjuer, enkäter, tester, undersökningar samt observationer har data samlats in för att förstå målgruppens behov och krav. Dessa behov och krav har sedan fått stå i fokus genom hela designprocessen för att komma fram till ett slutkoncept som skyddar händerna på ett innovativt, diskret och smidigt sätt.

  • 1016.
    Vaarama Danielsson, Adam
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Ahmedi, Omed
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Energikartläggning av kvarteret Bordsgossen i Gävle.Undersökning av energieffektiviseringsåtgärder passande flerbostadshus.2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 1017.
    Vachaparambil, Kurian Jory
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Karimipanah, Taghi
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Comparative Numerical Study of the Indoor Climate for Mixing and Confluent Jet Ventilation Systems in an Open-plan Office2018In: Proceedings of the 4th international Conference on Building Energy & Environment, Melbourne: Conference On Building Energy & Environment - COBEE2018, Melbourne Australia , 2018, p. 73-78Conference paper (Refereed)
  • 1018.
    Vachon, Francois
    et al.
    École de psychologie, Université Laval, Quebec City, Canada.
    Labonte, Katherine
    École de psychologie, Université Laval, Quebec City, Canada.
    Marsh, John E.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental psychology. University of Central Lancashire, Preston, Lancashire, England.
    Attentional capture by deviant sounds: a noncontingent form of auditory distraction?2017In: Journal of Experimental Psychology. Learning, Memory and Cognition, ISSN 0278-7393, E-ISSN 1939-1285, Vol. 43, no 4, p. 622-634Article in journal (Refereed)
    Abstract [en]

    The occurrence of an unexpected, infrequent sound in an otherwise homogeneous auditory background tends to disrupt the ongoing cognitive task. This "deviation effect" is typically explained in terms of attentional capture whereby the deviant sound draws attention away from the focal activity, regardless of the nature of this activity. Yet, there is theoretical and empirical evidence suggesting that the attention-capture mechanism underlying this form of distraction could rather be triggered in a task-contingent fashion. The present study aimed at determining whether the auditory deviation effect reflects the action of either a stimulus-driven or a task-contingent orienting mechanism. To do so, we conducted a systematic investigation whereby the impact of verbal deviants-a letter embedded in the repetition of another letter-and spatial deviants-a sound presented contralaterally to the other sounds-on verbal and spatial short-term memory (STM) was assessed. This study established that both verbal and spatial deviants can hinder both verbal and spatial order-reconstruction (Experiment 1) and missing-item tasks (Experiment 2). Such results demonstrate that the deviation effect reflects a general form of auditory distraction as interference took place both within and across domains and regardless of the processes engaged in the focal task.

  • 1019.
    Vachon, François
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental psychology. École de psychologie, Université Laval, Québec, CA.
    Marois, Alexandre
    École de psychologie, Université Laval, Québec, CA.
    Lévesque-Dion, Michaël
    École de psychologie, Université Laval, Québec, CA.
    Legendre, Maxime
    École de psychologie, Université Laval, Québec, CA.
    Saint-Aubin, Jean
    École de psychologie, Université de Moncton, Moncton, CA.
    Can ‘Hebb’ Be Distracted? Testing the Susceptibility of Sequence Learning to Auditory Distraction2018In: Journal of Cognition, E-ISSN 2514-4820, Vol. 1, no 1, article id 7Article in journal (Refereed)
    Abstract [en]

    Sequence learning plays a key role in many daily activities such as language and skills acquisition. The present study sought to assess the nature of the Hebb repetition effect - the enhanced serial recall for a repeated sequence of items compared to random sequences - by examining the vulnerability of this classical sequence-learning phenomenon to auditory distraction. Sound can cause unwanted distraction by either interfering specifically with the processes involved in the focal task (interference-by-process), or by diverting attention away from a focal task (attentional capture). Participants were asked to perform visual serial recall, in which one to-be-remembered sequence was repeated every four trials, while ignoring irrelevant sound. Whereas both changing-state (Experiment 1) and deviant sounds (Experiment 2) disrupted recall performance compared to steady-state sounds, performance for the repeated sequence increased across repetitions at the same rate regardless of the sound condition. Such findings suggest that Hebbian sequence learning is impervious to environmental interference, which provides further evidence that the Hebb repetition effect is an analogue of word-form learning.

  • 1020.
    Valtin, Evelina
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Analys av lågenergihus: Energieffektivt klimatskal2013Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har utförts i samarbete med Sigtuna Kommunfastigheter. Målsättningen med arbetet har varit att ta reda på vilken tekniklösning som skulle passa bra för nybyggnation av en energieffektiv förskola med tonvikt på klimatskal.

    Under arbetets gång har material samlats in i form av litteratur, studiebesök samt intervjuer med nyckelpersoner som har erfarenheter från tidigare byggda lågenergiförskolor och byggnader i relevant geografiskt område. Studierna visar att det finns ytterligare alternativ på byggnation av energieffektivhus som i viss omfattning har andra tekniklösningar.

    I samband med miljömålen som beslutas av EU och som Sverige också följer, växer efterfrågan på energieffektiva byggnader. Målen omfattar minskning av växthusutsläppen med 20 procent till år 2020, i förhållande till år 1990 ökning av energieffektivitetens med 20 procent. Eftersom byggsektorn står för 40 procent av Sveriges totala energianvändningen och ca 50 procent för den totala elanvändningen är det av stor vikt att tänka miljö- och energieffektivt när det gäller  nyproduktion av bostäder och lokaler.

    Passivhus är en av de lågenergibyggnader som svarar för energieffektiva bostäder och lokaler. Passivhuskonceptet och dess teknik  betraktas i det här examensarbetet. Passivhus är byggnader vars målsättning är att klara låga värmeförluster med installerad värmeeffekt på 10 till 12 W/m2 enligt de svenska passivhuskraven. Det finns även internationella krav för passivhus standarden vilka ställer strängare krav på värmebehovet. Det innebär att byggnader ska klara låga värmeförluster med installerad värmeeffekt på 10 W/m2 oavsett klimat förhållandena. I Sverige finns fyra färdigställda byggnader enligt den internationella standarden  där två av dessa studeras i den här analysen.

    Nyckeln för passivhuskonceptet ligger i lufttätheten, extra tjock isolering och välfungerande ventilationssystem med värmeåtervinning. De nämnda kriterierna är även svaga punkter i passivhusbyggnationen. Det innebär att litet misstag i utförande av arbetet gällande tätheten eller isoleringen för med sig allvarliga konsekvenser i form av fuktskador. Eftersom det inte finns något rätt eller fel avseende materialanvändning för produktion av lågenergibyggnader är det av stor vikt att ha fördjupade kunskap inom området och göra regelbundna kontroller under byggandets alla skeden.

    Studierna visar att det finns andra lösningar för energieffektiva byggnader med hög lufttäthet och miljövänlig materialanvändning. Exempel på ett sådant alternativ är byggnader av träullit. Materialet som består av träull och cement är även värmelagrande vilket gör att uppvärmningskostnaderna blir låga. Dessutom är materialet fukt- och brandsäkert.

    Efter de här studierna bedömer jag att det krävs fördjupade studier om befintliga lågenergihus i det svenska klimatet och vidare forskning för en miljövänlig och energieffektiv byggsektor. Detta kan hjälpa till att göra en adekvat bedömning av lågenergibyggnaders effektivitet i framtiden samt utmana att förbättra byggsektorn.

  • 1021.
    Vergés Gil, Albert
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Application of the hot-box technique to test the insulation effect of low-emissivity film on old windowsIndependent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 1022.
    Vestin, Hanna
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Entreprenörskap inom designbranschen: En fallstudie gjord i samarbete med Studio Lisa Bengtsson2018Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
  • 1023.
    Vestling, Magnus
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Barriärer och drivkrafter för effektiviseringsamt förutsättningar vid spillvärmeåtervinning: En fallstudie av Tegera Arena2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fokus på energianvändning är idag stort då forskare konstaterar att antalet naturkatastrofer som indirekt härrör från den globala energikonsumtionen ökar. Sverige står idag för 0,5 % av den totala energianvändningen globalt. Dock ligger Sverige och Europa i toppen vad det gäller energianvändning per capita. Den slutliga elenergi användningen 2015 var 30 % av den totala slutliga energianvändningen, till dessa slutanvändare hör ishallar, så som Tegera arena, som använder genomsnittlig 1000MWh/år köpt energi.

    Tegera arena förknippas troligtvis först och främst med Leksands IF hockeylag. Men utöver ishockey används arenan för andra evenemang och har en verksamhetstid under den större delen av året. Arenans energibehov är idag något större i jämförelse med genomsnittet för andra arenor med samma publikkapacitet och detta har uppmärksammats av föreningen.

    Ett samarbete mellan Leksands IF och det lokala fjärrvärmebolaget Dala Energi eftersöks. Detta utifrån den spillvärmeåtervinning från arenan som skulle kunna vara intressant för både föreningen, som internvärme, och energibolaget, i form av tillskottsenergi till fjärrvärmenätet. Detta kommer att undersökas med hjälp av andrahandsdata från både energibolaget och från föreningen. Genom analyser av dessa data kommer bottom-up och top-down-metod att användas. Resultatet av denna metod kommer sedan att jämföras med den totala verkliga användningen och sedan diskutera eventuella avvikelser. Även kommer intervjuer att göras för att studera vilka de främsta motsättningar och drivkrafter som föreligger hos föreningen för energieffektiviseringar.

    Resultatet från fallstudien visar att nära en tredjedel spillvärmeenergi används idag för det interna värmesystemet. Dock finns det ytterligare energi att använda internt. Detta utan att öka energiinnehållet med värmepump. Resultatet visar även att ekonomi är den största barriären men tillika drivkraft. Dessa två är inte ovanliga bland andra branscher, visar undersökningar. Annan drivkraft som föreningen anser vara betydande är fungerande installationer, då det idag finns förkommer problem med nuvarande tank för varmvattenackumulation.

    För utökad återvinning av spillvärme ges fyra förslag för det interna värmesystemet samt två stycken för den extern distribution. Att installera nya ackumulatortankar anges som högsta prioritet vid utökad återvinning vilket skulle ge en beräknad besparing på 90 kkr/år. Vid extern distribution föreslås det att leverera den lågtempererade spillvärmeenergin till annan närliggande varmvattenanvändare med höga laster. Detta i förstahand utan att använda sig av värmepump och istället använda spillvärmen till förvärmning.

  • 1024.
    Vicente Pina, Alejandro
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Analysis and consumption troubleshooting in a heat pump2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    One of the European Union priorities is the promotion of electricity generated from renewable energy sources. This is due to reasons of security and diversification of energy supply, environmental protection, reducing external dependence of the European Union (EU) in its energy supply and economic and social cohesion.

    The members of the EU as a whole, constitute the major world power in what concerns the development and application of renewable energy. The Maastricht Treaty assigned the EU's objectives of promoting sustainable growth respecting the environment. Meanwhile the Treaty of Amsterdam incorporated the principle of sustainable development in the objectives of the EU.

    The price support system for renewable energy currently prevailing in the EU is the system Renewable Energy Feed-in Tariffs (REFIT). The geothermal energy is considered as one of these renewable energies, so, it gets benefits from this system.

    In the concrete case of Sweden, almost 40% of the energy used is represented by the residential and services sector. So, to maximize the usage of renewable energy in these sectors is a priority for the country. In this way, low enthalpy geothermal energy is the easiest way of using geothermal energy in residential buildings.

    In this project it is studied a block of flats in N. Kungsgatan 37-43 (Gävle), whose heating and tap hot water system are handled by a geothermal heat pump combined with district heating. The system has been analysed because the consumption of electricity was higher than expected and this is a problem when the energy saving is the objective.

    For the analysis, different elements of the installation have been checked to verify if they are working correctly. For example, if the temperature sensors are giving properly information to the controlling system and the effectiveness of heat exchangers is the correct. The whole installation has also been carefully inspected with a thermal camera to check possible liquid or heat leakages in the machines room.

    Finally, after study the heat pump, the conclusion is that the problem is in the geothermal part of the heat pump, because the probes are not able to supply the required heat to the system. This is due to the geothermal installation was designed for another heat pump which was installed in the building some years ago. However, when the new installation was done in 2010, the geothermal installation was not changed for the new heat pump installation.

  • 1025.
    Vidhög, Adam
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Analys av sekundära lågtemperatursystem i ett fjärrvärmenät för ett planerat bostadsområde i Gävle2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a time where energy efficiency and saving measures are becoming more common terms in the energy industry, it is necessary to examine the district heating networks. One of the possible measures for efficient district heating is low-temperature secondary system. This thesis examines the potential benefits available with low temperature secondary heating systems versus conventional primary connections by comparing simulated models with the data collected from existing secondary system. The simulated cases in the report is modeled, calculated and simulated in the software NetSim. The results of the simulations demonstrated a reduced power requirement for the low temperature system with 4.8 kW, which approximately is a decreasing of 6 %. Heat losses from the simulated models turn out to be lower than the actual operating systems as a result of increased temperatures in the network. The difference between the simulated and real operating systems can therefore be useful in future projects for validation. Something that can be seen is that the line density of the secondary networks often is below what is considered as a profitable expansion. This does however not mean that secondary systems should not be built, as more aspects of a low temperature secondary system may be of interest to energy companies. The price models for secondary heat networks that were investigated differ, which could indicate that the market for secondary heat in district heating systems is young and under development.

  • 1026.
    Viguer Torres, Luis
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Fatas Perez, Borja
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Computer simulations of temperature and flow field in industrial spaces using confluent jets air supply method2012Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ventilation systems are closely connected to indoor environment. In industrial spaces it has a major impact due to air quality and thermal comfort requirements, which leads into health and economy improvements.

    Confluent jets ventilation system has been assess in Söderhamn Eriksson, a machinery company located in Mariannelund, Sweden, since it has been proved as the best ventilation performance. Moreover this system is worthy for both heating and cooling purposes, although just heating case will be developed in this thesis.

    By means of modelling software such as Gambit and Airpak, the company’s case could have been analyzed via Computational Fluid Dynamics (CFD) software, i.e. Fluent. The analyzed models were accepted after a thorough study of meshing parameters, bearing in mind computational limitations.

    Every temperature data gathered from simulation results has been verified with infrared camera figures taken at the company, thus contributing to reach reliable conclusions. As it is inferred from previous papers and empiric theory, the flow field observed is also justified. Then, thermal comfort and air quality analysis relies on consistent facts.

    It has been found that current ventilation at the company is slightly misadjusted, since supplied air’s temperature and velocity are slightly off point. Therefore, it is recommended to reduce these values to reach better working environment.

  • 1027.
    Villaro, Izaskun
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Analysis of the energy savings gained by protective glazing on stained single-glass windows at Uppsala cathedral2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Most European stained glass windows have no protection to reduce the damage due to environmental exposure, and this is the case of the great gothic windows in the Uppsala Cathedral. Currently, the implementation of protective glazing systems is being carried out in order to reduce the damage of the stained glass.

    In this connection, an analysis of the energy saving potential of the protective system is of great interest. The main obstacle in the implementation of this kind of systems is a social rejection based on the fact that the additional panes perturb the appearance of the historic building. Thus, demonstrating that there would actually be an energy saving, with the corresponding economic saving, would help approving the implementation of the protective glazing system.

    Measurement data needed for the analysis were available since they were used in condensation studies for the damaging analysis. However, the fact that this data was not gathered thinking of the energy saving analysis and its difficulties, some limitations have appeared in the present study. Accordingly, the needed simplifications imply some uncertainty in the results. However, the reliability of the results and the conclusions that can be drawn from the analysis are contrasted with previous similar studies.

    Different methods of calculation and analysis will be discussed, and finally results for the heat transfer coefficients through the open air gap and through the whole double paned system will be obtained. Furthermore, an energy saving analysis will be carried out with the winter data for both the case of the case of the Sonens fönster and the case of also implementing a similar system in the rosette of the cathedral. As a result, the conclusions drawn will be that the implemented protective glazing system reduces the heat losses through the windows to less than a third and that savings of about 8700 kWh/year and 13000 kWh/year are achieved in the case of the system being implemented only in Sonenes fönster and also in the rosette respectively.

    Finally, a rough study of the condensation problem will be exposed and possible matters, along with some advices, of further studies regarding more accurate analysis of both the condensation and the energy saving analysis will be presented.

  • 1028.
    Vitharanage, Rachitha
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Techno-economic Study of Performance Deterioration and Compressor Cleaning of Aircraft Gas Turbine Engines2010Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
  • 1029.
    Wahlborg, Dan
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Björling, Mikael
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Andersson, Lars T.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Allergenic potency of birch pollen2016In: Indoor Air 2016: The 14th International Conference of Indoor Air Quality and Climate, July 3-8 2016, Ghent, Belgium. Conference Proceedings / [ed] E. Van Kenhove, J. Laverge, P. De Vlieger, ISIAQ , 2016, article id 553Conference paper (Refereed)
    Abstract [en]

    The number of people sensitized to the major birch pollen allergen Bet v 1 in industrialized countries is vast and still rising. The purpose of this study was to develop a method with sensitivity high enough to measure the Bet v 1 content of a few birch pollen grains without the interference of environmental factors such as diesel particles, ozone level, humidity, temperature and precipitation. Grains were collected from catkins at two locations in Sweden over a period of 5 years. Allergens were extracted over polytetrafluoroethylene (PTFE) filters and Bet v 1 quantification was made with a luminescence immunoassay. The average content of Bet v 1 was 3.6 ± 0.6 pg per pollen grain for samples collected in three different pollination seasons. This is the first in a series of controlled experiments on the release of the major allergen Bet v 1 from birch pollen grains.

  • 1030.
    Wahlén, Johannes
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Förbättring av U-värde i träkonstruktion för fönster med Aerogel2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 1031.
    Wallhagen, Marita
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Building materials are important for sustainable development2017In: A good life for all: Essays on sustainability celebrating 60 years of making life better / [ed] Fagerström, Arne and Cunnigham, Gary M., Mjölby: Atremi AB , 2017, 1, p. 95-101Chapter in book (Other academic)
    Abstract [en]

    In the current material world human beings consume more natural resources and use more energy than ever before. The consumption of goods connected to planning, design and management of the built environment is seldom highlighted, even though the building and property sector is highly responsible for the use of large amounts of natural resources, production of waste and carbon dioxide emissions. This chapter describes important research that acknowledges environmental impacts of building materials.

  • 1032.
    Wallhagen, Marita
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Environmental Assessment of Buildings and the influence on architectural design2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This licentiate thesis examines environmental assessment tools for buildings. This is done by investigating, analysing, comparing and testing how different environmental assessment tools measure the environmental performance of buildings and examining the consequences this may have on architectural design.

    The study begins by analysing three environmental assessment tools: LEED, CSH and EcoEffect. These tools are then tested on a case study building (an eight-storey residential building) to analyse differences regarding assessment results, improvement proposals and potential impacts on architectural design.

    One of the environmental impacts assessed in the three tools, namely Climate Change caused by gases having Global Warming Potential (GWP), is then analysed in greater detail from a life cycle perspective by measuring CO2-equivalents (CO2-eq). A basic calculation tool (referred to as the ENSLIC tool), based on life cycle assessment methodology, is used to assess a case study building (a four-storey office building in Gävle). The impact of the building on CO2-eq emissions is calculated and the impact of a number of suggested building improvements and changes of energy sources is analysed. 

    The studies show the complexity of assessment tools and different ways to make comparisons. Both similarities and differences between the tools are apparent, regarding hierarchical structure and also on each hierarchical level, from categories to issues and parameters. It is also shown that the choice of environmental assessment tool may have an influence on the architectural design of buildings.

    The difficulty with assessing complex buildings is apparent even when only one environmental issue is assessed with the LCA-based ENSLIC tool. Many aspects influence the assessment result. These include energy use, choice of materials and choice of energy sources.

    The complexity and difficulty in linking buildings to environmental impact create a need for interactive tools measuring environmental performance, which can be useful as decision support in the early design phase.

  • 1033.
    Wallhagen, Marita
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering. KTH, Miljöstrategisk analys (fms).
    Environmental Assessment Tools for Neighbourhoods and Buildings in relation to Environment, Architecture, and Architects2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis explores Neighbourhood and Building Environmental Assessment Tools’ (NBEATs’) function as assessment tools and decision support, and their relation to environment, architecture and architects. This is done by analysing, testing, and discussing a number of NBEATs (LEED-NC, Code for Sustainable Homes, EcoEffect, LEED-ND, BREEAM-C, and ENSLIC-tool), their manuals and use. Moreover, professionals’ (architects’) self-rated opinions regarding use and knowledge of NBEATs and environmental aspects are surveyed.

    Similarities and differences in NBEATs are found regarding: content, structure, weighting and indicators used. Indicators distinguished as procedure, performance and feature are used to varying extents to assess social, environmental and technical aspects. NBEATs relation to environmental sustainability has limitations due to: non-transparency, tradable indicators, relative measures, low criteria levels, limited life cycle perspective, and exclusion of relevant environmental aspects, such as embedded toxic substances, nutrient cycles, land use change, and ecosystem services. Ratings and architecture are influenced by NBEATs in varying ways. Higher criteria levels would probably increase their impact on architecture. Thus more research regarding NBEATs and links to architectural design, theory and practice is welcomed.

    There is limited use of NBEATs as decision support in early design phases such as in architectural competitions. Architects rate the importance of environmental aspects high, but few rate their skill in handling environmental aspects high. This calls for increasing knowledge and know-how of environmental strategies and solutions among architects and adaptation of NBEATs to early design processes. The values NBEATs reflect and the values we want them to create is also important. To support ‘environmental’ architecture, an increased socio-eco-technological system perspective is put forward, and other measures besides NBEATs are needed.

  • 1034.
    Wallhagen, Marita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Eriksson, Ola
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Sörqvist, Patrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental psychology.
    Gender Differences in Environmental Perspectives among Urban Design Professionals2018In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 8, no 4, article id 59Article in journal (Refereed)
    Abstract [en]

    Urban design professionals are key actors in early design phases and have the possibility to influence urban development and direct it in a more sustainable direction. Therefore, gender differences in environmental perspectives among urban design professionals may have a marked effect on urban development and the environment. This study identified gender differences in environment-related attitudes among urban design professionals involved in the international architectural competition 'A New City Centre for Kiruna' in northern Sweden. Participants' self-rated possibility to influence environmental aspects was higher for males than for females. Conversely, the importance placed on environmental aspects had higher ratings among females, although the differences regarding the rating of personal responsibilitywere small. The gap between the participants' self-rated belief in their ability to influence and rated importance of environmental aspects was larger among female participants. Females placed great importance on environmental aspects even though they felt that their possibility to influence these was rather low. Conversely, male participants felt that they had the greatest possibility to influence, although some males rated the importance of environmental aspects thelowest. The gender differences identified are important froman equality and environmental perspective as they may influence pro-environmental behavior among urban design professionals and ultimately influence the environmental performance of the built environment.

  • 1035.
    Wallhagen, Marita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Glaumann, Mauritz
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Design consequences of differences in building assessment tools: a case study2011In: Building Research & Information, ISSN 0961-3218, E-ISSN 1466-4321, Vol. 39, no 1, p. 16-33Article in journal (Refereed)
    Abstract [en]

    Environmental assessment tools for buildings are emerging rapidly in many countries. Do different assessment tools influence the design process and also guide ‘green’ building projects in different directions? Three assessment tools, Leadership in Energy and Environmental Design for New Construction (LEED-NC), Code for Sustainable Homes (CSH) and EcoEffect, were tested in a case study project in Sweden: a new multi-storey residential building called Grönskär. The content and results of the three assessment tools were compared in general, while issues in the three core common categories of Energy, Indoor Environment and Materials & Waste were compared in more detail. The assessment results for the case study building varied with the three tools, and the design strategies and tactics to improve the overall rating of the building project differed for each tool. This confirms that the tools can influence sustainable building in different directions and illustrates insufficient consensus between assessment tools in terms of issues, criteria and weighting. The divergent results highlight the need for an appropriate structure of assessment tools that are both environmentally relevant and practically useful.

  • 1036.
    Wallhagen, Marita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering. KTH, MIljöstrategisk Analys - fms.
    Glaumann, Mauritz
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering. KTH Royal Institute of Technology, School of Architecture and the Built Environment,, Division of Environmental Strategies Research, Department of Urban Studies, Environmental Strategies Research - fms.
    Eriksson, Ola
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Westerberg, Ulla
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Building engineering.
    Framework for Detailed Comparison of Building Environmental Assessment Tools2013In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 3, no 1, p. 39-60Article in journal (Refereed)
    Abstract [en]

    Understanding how Building Environmental Assessments Tools (BEATs) measure and define “environmental” building is of great interest to many stakeholders, but it is difficult to understand how BEATs relate to each other, as well as to make detailed and systematic tool comparisons. A framework for comparing BEATs is presented in the following which facilitates an understanding and comparison of similarities and differences in terms of structure, content, aggregation, and scope. The framework was tested by comparing three distinctly different assessment tools; LEED-NC v3, Code for Sustainable Homes (CSH), and EcoEffect. Illustrations of the hierarchical structure of the tools gave a clear overview of their structural differences. When using the framework, the analysis showed that all three tools treat issues related to the main assessment categories: Energy and Pollution, Indoor Environment, and Materials and Waste. However, the environmental issues addressed, and the parameters defining the object of study, differ and, subsequently, so do rating, results, categories, issues, input data, aggregation methodology, and weighting. This means that BEATs measure “environmental” building differently and push “environmental” design in different directions. Therefore, tool comparisons are important, and the framework can be used to make these comparisons in a more detailed and systematic way.

  • 1037.
    Wallhagen, Marita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Glaumann, Mauritz
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Malmqvist, Tove
    Royal Institute of Technology, Division of Environmental Strategies Research, Department of Urban Studies, School of Architecture and the Built Environment, Stockholm.
    Basic building life cycle calculations to decrease contribution to climate change: Case study on an office building in Sweden  2011In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 46, no 10, p. 1863-1871Article in journal (Refereed)
    Abstract [en]

    This study examined whether simplified life cycle-based calculations of climate change contributions can provide better decision support for building design. Contributions to climate change from a newly built office building in Gävle, Sweden, were studied from a life cycle perspective as a basis for improvements. A basic climate and energy calculation tool for buildings developed in the European project ENSLIC was used. The study also examined the relative impacts from building material production and building operation, as well as the relative importance of the impact contributions from these two life cycle stages at various conditions.

    The ENSLIC tool calculates operational energy use and contributions to climate change of a number of optional improvement measures. Twelve relevant improvement measures were tested. The most important measures proved to be changing to CO2 free electricity, changing construction slabs from concrete to wood, using windows with better U-values, insulating the building better and installing low-energy lighting and white goods. Introduction of these measures was estimated to reduce the total contribution to climate change by nearly 50% compared with the original building and the operational energy use by nearly 20% (from 100 to 81 kWh/m2 yr). Almost every building is unique and situated in a specific context. Making simple analyses of different construction options showed to be useful and gave some unexpected results which were difficult to foresee from a general design experience. This process acts as an introduction to life cycle thinking and highlights the consequence of different material choices.

  • 1038.
    Wallhagen, Marita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Glaumann, Mauritz
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Westerberg, Ulla
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Understanding differences between the environmental assessment tools: LEED, Code for Sustainable homes and EcoEffectManuscript (preprint) (Other academic)
  • 1039.
    Wallhagen, Marita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering. Department of Sustainable Development, Environmental Science and Engineering, KTH, Royal Institute of Technology, Stockholm, Sweden.
    Magnusson, Peter
    Centre for Research and Development, Uppsala University/Region Gävleborg, Gävle, Sweden; Cardiology Research Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
    Ecological worldview among urban design professionals2017In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 9, no 4, article id 498Article in journal (Refereed)
    Abstract [en]

    The built environment is responsible for a large proportion of the global use of energy, natural resources, and emissions. Architects and other urban design professionals are key actors in the building process whose behavior and decisions will influence these impacts. Because environmental attitudes are linked to pro-environmental behavior, this study aims to measure environmental worldview among urban design professionals involved in the architectural competition ‘A New City Center for Kiruna’. The mean score registered for the New Environmental Paradigm (NEP) scale was 3.68 (standard deviation 0.51) and there were no significant differences with regard to age (mean 41.3 years) or gender (64.7% males). The ecological worldview of the participants was similar to most other samples from diverse countries, but a lower score was reported in comparison to environmentalists. The score ranged from 2.53 to 4.67 which shows heterogeneity at an individual level. Thus, future efforts to improve environmental attitudes among urban design professionals are needed.

  • 1040.
    Wallhagen, Marita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering. Division of Environmental Strategies Research, School of Architecture and the Built Environment, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Malmqvist, Tove
    Division of Environmental Strategies Research, School of Architecture and the Built Environment, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Eriksson, Ola
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Professionals' knowledge and use of environmental assessment in an architectural competition2017In: Building Research & Information, ISSN 0961-3218, E-ISSN 1466-4321, Vol. 45, no 4, p. 426-442Article in journal (Refereed)
    Abstract [en]

    In early design phases, architects, landscape architects and urban planners are key actors whose decisions determine the environmental impact of planning and building projects. Environmental and sustainability assessment tools for buildings and neighbourhoods have been developed to promote sustainable building, but their usage has not been thoroughly evaluated. This study investigated self-reported knowledge and usage of such tools among competitors and jury group from 10 European countries involved in the international architectural competition '€˜A New City Centre for Kiruna'€™ in Sweden. The questionnaire revealed that 13% used environmental assessment tools or management systems in the competition, although 47% had used them previously. Tool users reported greater knowledge of how to handle environmental impacts than non-users. However, the self-rated experience of handling various environmental impacts, in the competition and in general, was low for both groups. Nevertheless, the self-rated importance of environmental impacts was high among all participants. Based on this study, it is concluded that environmental assessment tools, issues and goals can be better integrated into the processes of early design in planning and building projects, and in architectural competitions. Furthermore, to limit environmental impacts in building and planning projects, professionals need to be educated about environmental strategies and solutions.

  • 1041.
    Wanasinghe, Buddhika Hasantha
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Steam driven boiler feed pumps for Lakvijaya Power Station, Sri Lanka2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Energy saving in coal power plants is a popular topic in present days with the global energy crisis. Internal electricity demand or auxiliary power consumption is an energy portion related with equipment supportive to the main equipment, which is unavoidable but with a proper investigation, some amount of this energy can be saved either by introducing thermally efficient auxiliary equipment or improving efficiencies of available equipment.

    Out of the various auxiliary equipment, the driving motor of boiler feed pump is the largest power consumer of internal electricity demand in 3x300 MW sub-critical Lakvijaya Power Station in Sri Lanka. So it is obvious that prime movers of feed pumps could be contributed for a large percentage of the losses. So it was decided to find out how to minimize the losses related to Boiler Feed Pump (BFP) system using small steam turbine to drive the BFP.

    The widely used alternatives for the BFP drivers are condensing type and back pressure type steam turbines. Eleven (11) different configurations of Condensing type, back pressure type and also extraction back pressure type turbines were considered and software programs for each configuration were implemented using Engineering Equation Solver (EES) software. The considered configurations are different to each other by inlet steam thermodynamic parameters, steam flow rate, exhaust thermodynamic steam parameters and intermediate extraction parameters etc.

    Thermodynamic analysis ended up with interesting solutions while all the configurations are giving improved efficiencies than existing electrical motor driven mode. But some of them had not improved their net output and hence there were no gain in net generator power output although the efficiencies are higher. Out of other configurations with improved net output and efficiency, the case with back pressure turbine arranged parallel to the HP turbine had the highest net output gain with better improvement in efficiency without changing the input power to the boiler. Considering the CO2 , SOx and NOx emissions, it was cleared that power plant with suggested BFP modes will give more clean energy than existing power plant.

    Considering the partial loads behavior it was observed that power plant with Back pressure turbine, steam extracted from HP turbines inlet for prime movers of boiler feed pumps is more thermodynamically economical than existing power plant.

    Annual financial saving with BFP configurations with positive net output gain and zero boiler input gain were calculated and it will be in between 0.46 and 2.72 UDS million / Year.

  • 1042.
    Wang, Fengyuan
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Shi, Rui
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    CO2 emission in China and Europe: compare China and Europe1989Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Realize the situation about CO2 emission in Europe and China. Find out which reasons caused the CO2 emission will be changed. We did the data collection: CO2 emissions from China and EU. Energy consumption (include the total, electricity and transportation) and energy structure. Increased CO2 emission caused by Global warming. The CO2 emission increased with fossil-fuel use increased.

    China almost used of fossil energy, in 2004, domestic use for coal achieve to 67.7% of the total energy consumption. In 2010, the coal supply account for 48% of the world; the coal supply in 2000 to 2009 increased 85.5%. The CO2 emissions in 2009 is 6803.92 mil-tones, increased 13.32% than 2008, No. 1 of world.

    EU energy structure is keep changed, the rate of utilization for traditional fossil-fuel was gradually reduced. In 2010, the EU coal supply 8% of the world, 2000-2009 presents negative growth (3.8%). The CO2 emissions in 2009 were 4310.3 mil-tones, more than 2008 years to reduce 6.9%.

    CO2 emission based on energy consumption; Energy consumption is supply a variety of services to people. We must consider with population. China’s CO2/per capita less than average level in world, and lower than most EU countries.

      China and EU are planning for future energy structure (reduce the use of fossil-fuel and increase renewable energy construction), that means up to energy saving and emission reduction purpose. The emission reduction of focus is to change the energy structure, reduce fossil-fuel use.

    China predicting the coal utilization rate under 60% of the total energy consumption. Thus, by 2020, forecast reducing 40-45% CO2 emission based on 1995. EU energy structure better than china, while they planning energy saving reach 20% at 2020, and improve the renewable energy use. By 2020, EU-27 forecast reducing 20% CO2 emission based on 1990 CO2 emission.

  • 1043.
    Wang, Hao
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Numerical study of cooling demand and thermal performance for different wall constructions.2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 1044.
    Wang, Kangkang
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Assessment of photovoltaic application on a residential building in Gävle, Sweden2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The paper presents a PV-based electricity generation system of residential building located at Norra Fiskargatan in Gävle, Sweden, and aims to examine the environmental performance of PV-based electricity generation systems by conducting a thorough investigation of photovoltaic utilities of residential buildings. This paper also investigates the carbon dioxide emission reduction due to the use of the PV will estimated for the service lifetime of the PVs (30 years).

    A comparison between carbon dioxide emission of a PV-based electricity generation system and an electricity grid, during the lifetime of the PV-system. The results show if PVs installed on residential buildings, the electricity produced by grid can be reduced and the carbon dioxide emissions will be saved from the electricity grid.

  • 1045.
    Wang, Q.
    et al.
    Department of Atmospheric Sciences, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China .
    Sandberg, Mats
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Hang, J.
    Department of Atmospheric Sciences, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, China .
    Assessment of air change rate and contribution ratio in idealized urban canopy layers by tracer gas simulations2014In: Indoor Air 2014 - 13th International Conference on Indoor Air Quality and Climate, 2014, p. 470-477Conference paper (Refereed)
  • 1046.
    Wang, Qun
    et al.
    School of Atmospheric Sciences, Sun Yat-Sen University, Guangzhou, China.
    Sandberg, Mats
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Lin, Yuanyuan
    School of Atmospheric Sciences, Sun Yat-Sen University, Guangzhou, China.
    Yin, Shi
    Department of Mechanical Engineering, The University of Hong Kong, PokFuLam Road, Hong Kong, China.
    Hang, Jian
    School of Atmospheric Sciences, Sun Yat-Sen University, Guangzhou, China.
    Impacts of Urban Layouts and Open Space on Urban Ventilation Evaluated by Concentration Decay Method2017In: Atmosphere, ISSN 2073-4433, E-ISSN 2073-4433, Vol. 8, no 9, article id 169Article in journal (Refereed)
    Abstract [en]

    Previous researchers calculated air change rate per hour (ACH) in the urban canopy layers (UCL) by integrating the normal component of air mean velocity (convection) and fluctuation velocity (turbulent diffusions) across UCL boundaries. However they are usually greater than the actual ACH induced by flow rates flushing UCL and never returning again. As a novelty, this paper aims to verify the exponential concentration decay history occurring in UCL models and applies the concentration decay method to assess the actual UCL ACH and predict the urban age of air at various points. Computational fluid dynamic (CFD) simulations with the standard k-ε models are successfully validated by wind tunnel data. The typical street-scale UCL models are studied under neutral atmospheric conditions. Larger urban size attains smaller ACH. For square overall urban form (Lx = Ly = 390 m), the parallel wind (θ = 0°) attains greater ACH than non-parallel wind (θ = 15°, 30°, 45°), but it experiences smaller ACH than the rectangular urban form (Lx = 570 m, Ly = 270 m) under most wind directions (θ = 30° to 90°). Open space increases ACH more effectively under oblique wind (θ = 15°, 30°, 45°) than parallel wind. Although further investigations are still required, this paper provides an effective approach to quantify the actual ACH in urban-like geometries.

  • 1047.
    Wang, Zhao
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Liu, Longcheng
    Department of Chemical Engineering and Technology, Royal Institute of Technology, Stockholm, Sweden.
    Neretnieks, Ivars
    Department of Chemical Engineering and Technology, Royal Institute of Technology, Stockholm, Sweden.
    Hard-sphere fluid mediated interaction: a pressure expression with application of the weighted correlation approach2016In: Molecular Physics, ISSN 0026-8976, E-ISSN 1362-3028, Vol. 114, no 5, p. 599-607Article in journal (Refereed)
    Abstract [en]

    By using a so-called differential-integral method on the chemical potential of a hard-sphere fluid, a special variant of our previously developed expression that describes the interaction between charged plates immersed in an electrolyte, is introduced to examine the hard-sphere fluid mediated pressure in a slit. The resulting expression consists of a kinetic contribution and a hard-sphere contribution, and it is formulated as a function of the single-particle direct correlation function and the density distribution of a hard-sphere fluid. It allows us to conveniently apply the classic density functional theory to explicitly investigate the influence of the hard-sphere excluded-volume effect on the interaction pressure between surfaces. In this study, a newly proposed weighted correlation approach (WCA)-Denton and Ashcroft (DA) method is employed to predict the interaction pressure as well as its pressure components for a hard-sphere fluid inside a slit pore. Comparisons with the results from the Monte Carlo simulations and the fundamental measure theory suggest that the WCA-DA method is able to accurately capture the detailed characteristic pattern of the pressure-separation curves at different fluid densities. It is also found, both qualitatively and quantitatively, that the hard-sphere pressure contribution dominates over the kinetic pressure contribution in determining the oscillatory behaviour of the interaction pressure curves, especially when a hard-sphere fluid of high density is concerned.

  • 1048.
    wang, zhong tao
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    liu, qian
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Breeze Wind Power In China2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    China is an energy production and consumption country, wind power is one of the greatest development potential energy.The authors use literature research methodology, case study, comparative study and trend analysis study to analysis current condition of the breeze wind power.China has a long history of wind development, use wind power to generate electric is only developed in recent years, but it is expanding fast. China is a country covering vast territory, and it is rich in wind resources. But some reasons such like natural, economy, environmental etc, limit the wind power development of China.The VAWT is a new kind of wind driven generator, it has many advantages that HAWT doesn’t have. Utilize VAWT to develop breeze wind power generation, will bring wind power into more families.

  • 1049.
    Wang, Zhongtao
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Investigation of alternative energy and renovation opportunities for villa2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Calculate energy consumption; investigate alternative energy and renovation opportunities for a villa is the main purpose of this thesis.

     

    The calculation processes contains both hand calculation and IDA-ICE building energy modelling simulation. After validation for both hand-calculation and modelling simulation results, several energy investigations are done in the villa: introducing of heat pump, sol energy, district heating etc. for energy opportunities. Meanwhile, some building renovation suggestions for construction improvement are also introduced to reduce the energy consumption. At the end of the result part, the author combines different energy and renovation methods to improve the energy performance of villa. The result shows that, the villa has good energy potential to meet the BBR standard. And the investment for renovation is acceptable.

     

    LCC analysis is also considered during the investigation and renovation processes. That makes the results of investigation and renovation become more convincible and more economically.

     

    The discussion and conclusion part, the author make a conclusion about different renovation method, meanwhile the author also discuss about the advantage and disadvantage of the thesis, which will make the author improve in the future project.

  • 1050.
    Wangel, Josefin
    et al.
    Division of Environmental Strategies Analysis (fms), KTH Royal Institute of Technology, Stockholm, Sweden.
    Wallhagen, Marita
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering. Division of Environmental Strategies Analysis (fms), KTH Royal Institute of Technology, Stockholm, Sweden.
    Malmqvist, Tove
    Division of Environmental Strategies Analysis (fms), KTH Royal Institute of Technology, Stockholm, Sweden.
    Finnveden, Göran
    Division of Environmental Strategies Analysis (fms), KTH Royal Institute of Technology, Stockholm, Sweden.
    Certification systems for sustainable neighbourhoods: what do they really certify?2016In: Environmental impact assessment review, ISSN 0195-9255, E-ISSN 1873-6432, Vol. 56, p. 200-213Article in journal (Refereed)
    Abstract [en]

    Certification systems for sustainable neighbourhoods started to emerge around a decade ago. This study analysed the content, structure, weighting and indicators of two established certification systems for sustainable urban development - BREEAM Communities and LEED for Neighborhood Development. Several limitations of these systems were identified: both have a bias for procedure and feature indicators over indicators that assess actual performance; performance demands are set according to a relative understanding of sustainable development; the focus is on internal sustainability, while upstream and downstream impacts of construction are disregarded; the number and distribution of mandatory issues do not cover essential sustainability aspects; and the disproportionately large number of non-mandatory issues makes benchmarking difficult and signals that sustainability aspects are exchangeable. Altogether, this means that an area can be certified without being sustainable. Moreover, the lack of continuous development of certification requirements in the systems means that they risk exerting a conservative effect on urban development, rather than pushing it forward.

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