The district heating load is seasonally dependent, with a low load during periods of high ambient temperature. Thermal energy storage (TES) has the potential to shift heating loads from winter to summer, thus reducing cost and environmental impact of District Heat production. In this study, a concept of high temperature borehole thermal energy storage (HT-BTES) together with a pellet heating plant for temperature boost, is presented and evaluated by its technical limitations, its ability to supply heat, its function within the district heating system, as well as its environmental impact and economic viability in Gothenburg, Sweden, a city with access to high quantities of waste heat.The concept has proven potentially environmentally friendly and potentially profitable if its design is balanced to achieve a good enough supply temperature from the HT-BTES. The size of the heat storage, the distance between boreholes and low borehole thermal resistance are key parameters to achieve high temperature. Profitability increases if a location with lower temperature demand, as well as risk of future shortage of supply, can be met.

This thesis includes an energy survey of the Herrgården pre-school, which has a modern heating- and ventilation system, and a comparison with Östers pre-school which has an older system. An energy survey of Östers pre-school has already been done by a group of three students and all the calculations and values have been collected from that survey. As of today, both pre-schools are heated thru district heating. It will be much easier to make smart and feasible energy-saving-measures by first conducting the energy survey.Herrgården pre-school in Gävle houses 81 children, therteen teachers, one cleaner and one cook. It was finished in the middle of 2009 and the staff has been very pleased with the in-door climate.

This thesis includes an energy survey of the Herrgården pre-school, which has a modern heating- and ventilation system, and a comparison with Östers pre-school which has an older system. An energy survey of Östers pre-school has already been done by a group of three students and all the calculations and values have been collected from that survey. As of today, both pre-schools are heated thru district heating. It will be much easier to make smart and feasible energy-saving-measures by first conducting the energy survey.Herrgården pre-school in Gävle houses 81 children, therteen teachers, one cleaner and one cook. It was finished in the middle of 2009 and the staff has been very pleased with the in-door climate.

One of the city of Stockholm?s main objectives is to have a society completely free from fossil fuels. To achieve this, several investments regarding improvements in energy efficiency and renewable energy are currently being planned or implemented. One of these investments is a project called Hallbara Jarva which is located in the suburbs of Stockholm. The purpose of this thesis is to examine the prospects of an investment in photovoltaic cells from an energy-saving and economical point of view. The analysis is limited to three buildings within Hallbara Jarva and is intended for the property owner.  Solar energy is a type of renewable energy source and is commonly divided into solar heating and solar power.

The biogas plant Kungsängens gård, owned by Uppsala Vatten och Avfall AB, produces biogas and biomanure from organic household waste, food processing waste and slaughterhouse waste. In year 2012, 4.4 million Nm3 of biogas were produced from 25 200 tons of waste. Before digestion all substrate is sanitized by one hour?s pasteurization at 70°C in order to kill pathogens. Another method, integrated thermophilic sanitation (ITS), is of interest in order to decrease the energy demand.

The high level of energy consumption that the industrialised countries have reached and thepollution that this brings has long been a cause for analysis and debate, development and usageof so called renewable energy sources is therefore more important than ever. The energy in theelectromagnetic radiation from the sun is an interesting alternative. One way of harvesting thisenergy is by using solar cells, devices that generate DC current when exposed to electromagneticradiation.The goal of this master?s thesis was to design a solar powered power supply to Syntronic AB?sMidrange platform. The envisioned application is a stand-alone distributed embedded system,for example a node-based temperature monitoring system.

The climate changes that are occuring in the world have resulted in that the EU callingfor a 20 % reduction in energy consumption to the year 2020, to reach that goal theEU want the public sector to go forth as a good example. Västfastigheter owns andmanage the hospital buildings in the Västra Götaland region. To be able to reducetheir energy usage Västfastigheter has hired several consulting firms to chart out theenergy consumption on each hospital building. The biggest energy savings potentialhave been calculated and what the cost will be to perform each action. The energyaudit have been completed and stand as the decision basis for Västfastigheter?s choiceon which action packages that should be implemented.

The purpose of this study is to create a method that can be used to produce decisionsupport data for the climate goals of a municipality. The method should be able to demonstrate the potential for reducing energy use and greenhouse gas emissions for measures aimed at the stationary energy system in the municipality. It will be used to make longterm projections of energy use and greenhouse gas emissions in order to be able to demonstrate the ability to reach climate goals. The aim was also to test the method's applicability by using the municipality of Uppsala and the Uppsala climate protocol project in a case study. Uppsala climate protocol is a project consisting of participants from business, government and organizations that voluntarily want to commit to reducing their carbon footprint by reducing their energy use and thus work to achieve the municipality's overall climate goal. Public reporting of energy use and climate impact has been studied in order to examine the nature of indicators and accounting figures that are commonly used in the field and how long-term forecasts are formulated. In connection to this, the type and sources for the kind of data needed was also examined.

Drain water heat recovery is an uncommon measure in multi-unit residential buildings. There istechnology available for the purpose but the knowing and experience of the heat recovery systems islittle. The purpose of this thesis is to evaluate the future potential of drain water heat recovery inmulti-unit residential buildings.A major part of the multi-unit residential buildings in Sweden were built during modernismen andrekordåren (1940?1975). Many of the buildings have worn out drain and water supply systems andmany are in need of a general refurbishment.

This thesis includes an energy survey of the Herrgården pre-school, which has a modern heating- and ventilation system, and a comparison with Östers pre-school which has an older system. An energy survey of Östers pre-school has already been done by a group of three students and all the calculations and values have been collected from that survey. As of today, both pre-schools are heated thru district heating. It will be much easier to make smart and feasible energy-saving-measures by first conducting the energy survey.Herrgården pre-school in Gävle houses 81 children, therteen teachers, one cleaner and one cook. It was finished in the middle of 2009 and the staff has been very pleased with the in-door climate.

Energy price are on the way up to a high level that will not diminish in the future make us to focus more on the sustainable development for a better solution of residential houses. Passive house or low energy housing are one of the solution to make residential more environment friendly, in same time it´s a financial security using less energy, and saving money. The last 10 years in Germany and all around Europe the concept of passive house been developed, and people aim to know more about these concept that leading the market more attractive for passive houses. A passive house is a well designed building highly insulated and air tight with mechanical ventilated system for the whole building envelope that minimizes the use of energy for heating [1].The housing company Mimer has chosen to invest in low energy consumption in every new housing project.  These future plan projects are decided to use less than 75 kwh per square meter annually in purchased energy [2].This thesis is about new constructed passive houses, and focuses on the evaluations of the temperature, and moisture condition for attic, external walls and joist.

AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.

In this work, a method was developed and evaluated for calculating the life of welds under the influence of fatigue loads from a vibration environment. Typically, a shaker table is used for testing a component against vibration loads. The shaker table creates a vibration environment that is defined in the frequency domain by a power spectrum.Similarly, a virtual vibration table can be used to calculate the same type of load environment, which can then be used to calculate the expected lifetime. The benefit of this method is that it can be used in design, as well as in simulation of tests before physical verification tests are carried out.Today there are methods for calculating fatigue life of non-welded base material, but since many components contain welded joints, there is a need to apply this method to those types as well. To achieve this, the thesis combines two different areas, which together provide a method for fatigue assessment of welds using a virtual shaker table.The methodology is carried out by modeling the component, and its welded joints, in a finite element program.

The design of the building envelope affects the energy consumption of a building. As the energy requirements for new buildings are becoming more demanding, the performance of the building envelope must be improved. Energy efficiency and durability are important attributes to consider.This report includes investigations of the building envelope, moisture and passive solar energy. It is based on the analysis of two different buildings with different designs. These buildings stand as reference for two of the companies who are working on a new, climate smart, residential area in Uppsala, Sweden.Studies and analyses on energy consumption and moisture transportation were made.

This thesis tries to clarify why more houses such as passive houses is not built and at the same time the differences is described with the conventional construction as a starting point. Sweden has set environmental objectives to reduce energy consumption in buildings by 50 percent by the year 2050 compared to 1995. The passivehouse concept could have a significant role, particularly in the reconstruction of buildings with high energy consumption. For sustainable building the passivehouse technology is an economically viable concept while benefiting the environment. Initially an introduction is given of the background to the problem, purpose and objective of the thesis.