Hydropower is an important source of energy in Sweden and accounts for about 46 % of the total energy production. Sweden has about 1 200 hydropower plants and with the intention of raising the pressure head of the water and to store water, dams are built by the power plants. The storage reservoirs make it possible to adjust the energy production by demand and season. Dams in connection to the reservoirs are subjected to additional loading during periods of high floods or when an icecap in the winter is formed on the reservoirs. In order to maintain the dam safety, the power companies in Sweden are working with guidelines for dam safety from RIDAS.

In today?s society a large focus is put on energy systems and how our energy systems are built up. In order to make sure that we in the future still can enjoy the living standards that we are used to today, Sweden and EU have made a number of decisions on making our energy system more energy efficient and consequently reduce the usage of energy resources. By 2020 the European Union should have reduced its energy consumption by 20 % compared to 1990?s level, and by 2050, 50%.

Buildings worldwide account for 40 % of the total energy use. Climate change is of increasing importance, but few are willing to reduce their standard of living or get a higher cost for the change. Energy efficiency of existing buildings gives the greatest benefit economically and environmentally. The real estate company Klövern AB manages 46 properties in Karlstad. Heating is the major cost of the total operating costs of real estate. Rising energy prices increase the need for Klövern AB to improve energy efficiency and to investigate alternative sources of heat.

The Goal with this Master of Science thesis is to expand the possible turbine efficiencymeasurements on an exhaust turbocharger. It was done as a part of the CICERO competencecentre. To feed the turbine with air a special flow rig has been used. Instead of loading theturbine by just restricting the compressor flow a docking system for an electrical dynamometer isdesigned to use the dynamometer as an additional loading source. By using an electricaldynamometer as loading device for the turbine, measurements are not depending on compressorperformance.A large part of the work consists in designing accessories for the dynamometer.

In Sweden, the eutrophication of lakes, water courses and the coastal areas is considered the major threat to aquatic ecosystems and therefore actions taken to reduce the nutrient load to aquatic system including the Baltic Sea has high priority. There are many different sources of phosphorous and nitrogen and domestic wastewater is one contributing factor to the high load. Especially waste water from households that is not connected to municipal sewage treatment or a local small scale plant with appropriate nutrient removal efficiency is considered a problem. These types of households are quite common in rural areas in Sweden and in areas where summer houses has been converted to permanent living. Swedish legislation now permit the municipalities to decide in which areas within the municipality higher demands of the local small scale treatment facility should be met by the households (i.e.

The project contains a force analysis of the vertical axis wind turbine Lucia's supporting arms and a measuring device to experimentally measure the forces is made. The forces between the supporting arms and the tower are calculated theoretically and then simulated by a computere. A measuring devise is then designed to measure the forces experimentally. The forces acting on the attachment between the supporting arms and the tower is primarily the centripetal force, gravitational force and the aerodynamic forces on the rotor wings. The maximum forces were theoretically calculated and is 13.38 kN along the x-axis, -0.25 kN along the y-axis and then 0.5 kN along the z-axis.

The first part of this essay is about a single-family house that we have planned and projected. Thesecond part is a deeper study in ways to further insulate windows when they are not in use.In the first part the building?s design and its most important construction elements are described.The planning of all major installations (heating, domestic water, ventilation, sanitation, electricity)are reported so that one can in principle start construction of the house. In addition there arecalculations done on the building?s energy management.The result is a two stored house angled toward the south.

Regulations on the exhaust emissions of HD-diesel engines are becoming more and more stringent, and therefore, emission after-treatment systems are commonly used. These systems rely on catalytic conversion of NOx,CO , and HC emissions, and are thus dependant on temperature. At low load of the engine, exhaust temperatures are not sufficient for the after-treatment components. Therefore, means to increase the exhaust temperature while maintaining low emissions and fuel consumption are needed.The focus of this project has been to develop strategies for the lift profiles of exhaust and intake valves in the engine, with the goal to raise exhaust temperature in combination with low emissions and fuel consumption. The strategies have been tested in a single-cylinder research engine equipped with a hydraulic variable valve actuation system.

Detta examensarbete utgör resultatet av en studie på uppdrag av Volvo Cars Torslanda (VCT) i Göteborg. Syftet med studien har varit att undersöka produktflödena mellan VCT och dess leverantörer med hjälp av analyser. Dessutom utreds hur transporterna skulle kunna optimeras och vilka konsekvenser som uppstår. Beräkningar, diskussioner och analyser resulterar i rekommendationer för företaget.För att få mer kunskap om transportlogistik, produktionsekonomi och miljöpåverkan av transporter genomförs först en litteraturstudie. En granskning av nuläget beskriver hur situationen ser ut i dagsläget och ger även en detaljerad bild av flödena från leverantörer till VCT.Sex stycken flöden vars gods transporteras från leverantörer till VCT har undersökts.

Förmågan att prestera under akut eller kraftig stress är en förutsättning för en del yrken. Forskningsresultaten gällande hur stress påverkar prestation pekar åt olika håll. Denna studie undersökte sambandet mellan fysiologisk arousal och kognitiv problemlösningsförmåga under stress. Trettiotvå polisstudenter testades på Ravens test av flytande intelligens APM set II både före och efter att antingen ha sprungit i tjugo minuter eller haft en självskyddslektion på ca fyrtio minuter. Resultaten från en mixed ANOVA för beroende mätningar visade på en signifikant interaktionseffekt (F (30) = 6,547, p < 0,05) ? en ökning i prestationen hos självskyddsgruppen med arton procent och en minskning med femton procent hos löpningsgruppen.

To build high-rise buildings made of timber has for long been limited by national laws, due to the lack of knowledge in engineering solutions. Frame structures made of wood has for a long time been associated with major fire hazards and consequently lower safety and this connection is still being made today. The increased environmental awareness in recent years has contributed to the exploitation of indigenous building materials, including wood from our own Swedish forests and has become increasingly common. Increased knowledge about how structures behave in fire and how they can be protected in order to achieve safe timber structures has resulted in a growing interest in these structures in the construction industry. Research in the area is constantly updated and new laws allow any number of storeys in wooden buildings in Sweden as long as the performance requirements are fulfilled.The main part of this work has involved calculations of the fire resistance and load bearing capacity of floor and wall constructions.

AbstractThe tests work is about the subject "synergism of steel and concrete."The construction sector is in a strong competition and the different companies in the PrefabMarket has ever tried to develop new design solutions that are efficient and environmentallyfriendly.The purpose of this report is to highlight different aspects of interaction and size up a columndimension and to examine its efficiency and load capacity as Eurocode 3 and Eurocode 4. A sizing chart that describes the relationship between the torque and normal force shouldalso be made of the interaction . .

District heating covers around 80 % of the heating demand in apartment buildings and 10 % in single-family homes in Sweden. In the year 2010 the total input of energy to the Swedish district heating grids was about 70 TWh, which corresponds to 11 % of the total energy input to the whole energy system in the country. Through the combined production of heat and power the CHP-plants often reaches an efficiency of 90 % from energy in the fuel to produced heat and power. In order to keep the efficiency high it is important for the owners of the plant to have good knowledge about the plants performance at different operation points. Strängnäs Energi AB initiated this diploma work together with FVB Sverige ab in order to come up with a program for short term planning of the production of heat and power at the company´s CHP-plant.The work consists of three main parts.

Energy efficiency is important both to reduce costs and to reduce greenhouse gas emissions in the atmosphere. Reducing costs will also help maintain business competitiveness.Scania in Södertälje is a company where the optimization of energy use is an ongoing and continual process. One area with potential to make energy and cost savings is the effectiveness of the ventilation systems in offices and industrial premises at Scania. During the summer months an increased demand for cooling occurs, leading to increased ventilation and a peak in district cooling system usage. Sorptive cooling is a technology where the supplied air is cooled by applying external heat.

The thermal response of a borehole field is often described by non?dimensional response factors called gfunctions.The g?function was firstly generated as a numerical solution based on SBM (Superposition BoreholeModel). An analytical approach, the FLS (Finite Line Source), is also accepted for generating the g?function. In thiswork the potential to numerically produce g?functions is studied for circular borehole fields using the commercialsoftware COMSOL.