A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.

When one experiences a place, it is a complex composition of both social and spatial factors.One of these spatial elements, is scale, which is influenced both by the room size and itsproportions. This paper aims to explore both large and small scale concepts and thus increasethe understanding of how scale directly and indirectly affects the experiences and uses ofurban space.First, is a theoretical discussion of scale in relation to aesthetics and the differencesbetween real scale and perceived scale. Next, is an analysis of spatial perception usingexamples from two existing sites. One, which is understood to have been planned in a largescale and one which is understood to have been planned in a small scale.When preparing this paper, the focus quickly became the importance of scale as itrelates to street spaces. The perception of a street usually takes place while in motion, whichforces it to be perceived in sections.

Lower energy use in buildings is a result of increasingly stringent energy requirements across Europe. When conventional district heating technology is used in areas with low energy consumption heatlosses do not fall even though the amount of energy delivered is reduced. This reduces income for thedistrict heating company. To maintain their economic viability the district heating companies? majorchallenge is to implement new solutions that minimize heat loss.

Arlanda airport is Sweden?s largest airport. The demand for comfort cooling of the airport?s buildings is high and is mainly provided by district cooling. District cooling is based on the same principle as district heating.

A district heating plant has the advantage that it can take advantage of the waste heat from industries and use of cheap fuels to produce heat. But for the long term is competitive requires that energy is also saved in district heating plants. One way to save energy in a district heating system is to increasing cooling to the return temperature. This leads to less power needed to drive the distribution pumps,  and that more energy could be extracted from the same amount of fuel by an improved flue gas condensation.In Karlskoga the return temperature into the district heating plant is high. They would therefore reduce the return temperature in order to extract more energy from the flue gases.

Uppsala County has ambitious environmental aims for the planned residential area inÖstra Sala backe. In this thesis different energy sources have been evaluated todetermine which system that would be most favorable given currently availableinformation about the project. Planned energy usage has been divided into tap waterheating, space heating and power. Three base case scenarios were made with districtheating, small scale bio fuel and heat pump. Solar power and solar heating were thensimulated and the production from the two could individually be deducted from theenergy need in the base cases, constituting 9 different scenarios.

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 concerns an energy audit of a food industry. The company's business consists of boiling and peeling shrimps, and producing mayonnaise-based salads. This type of work involves energy-intensive processes, such as steam generation, compression of air and refrigeration of large spaces. These needs are supplied with electricity. Furthermore, the industry is a major consumer of district heating, particularly for heating the supply air in the ventilation system.

The aim of this study was to develop a load prognosis model for Uppsala district heating system to be used as a tool for heat production optimization. The methodwas to build three models for the different customer types; housing, industry andoffices and then scale them for the total system using data from Uppsala districtheating system. The heat load consists of two parts, one that is temperaturedependent and one that is dependent of the social behavior of the customers. Thetemperature part was modelled with an ARX model using an outdoor temperatureprognosis as input signal. The social behavior part was modelled using the mean ofthe social behavior from some days before and additionally by distinguishing betweenweekdays and weekends.

The intrest and development of bioenergy and energy from renewable sources in Sweden has increased rapidly over the last few years. There are a whole lot of alternatives for those who would like to venture and invest in renewable energy production. Production of renewable energy opens up many opportunities for forestry and farming to venture a new branch of production, on basis of the primary production. Several of the new energy sources grows on farmland or in the forest. The opportunities exist in the primary products, as well as in refining and reselling, in the value chain of energy. The starting-point is the Farmer as an energyproducer. This master thesis studies the nature of farmer-own firms, who has invested in production of renewable energy.

AbstractBackgroundThe Swedish district heat market of today is a subject being discussed regarding the reasonableness of the heat district supplier?s price settings. The issue is currently on a government level where a new investigation is being executed at the time of writing. Many real estate owners are growing tired of the situation where the heat district suppliers are taking advantage of their monopoly position, thus feeling that the price of district heating has been increasing far too much for many years. The market can be described as a natural monopoly because the real estate owner has no possibility to choose another supplier if they are unsatisfied with the present.

This thesis examines different methods for the cooling of data centers. Several means of cooling with the refrigeration cycle have been studied, as well as the feasibility of using free cooling in different parts of Sweden. In addition, the possibilities of transferring excess heat to a nearby district heating system were investigated. It was found that in all investigated cases except two, the data center could be cooled solely with free cooling for at least 300 days a year when only the outside air temperature was considered as a constraining factor. The limit was then set to 20 °C.The vast majority of all district heating systems in Sweden get little to none of their heat from other excess heat sources.

At the moment in central Täby there are small district heating network operated by Fortum Heat. The distribution network has an annual heat demand of about 70 GWh, which is supported by the network's two plants, Galten and Farmen. Täby as a region is rapidly growing and there are grand plans to develop the area. Estimated market potential for a future district heating expansion in Täby is very high and as early as in 2007 Täby decided to invest in a large-scale expansion. In autumn 2009 Täby did a procurement process, known as the ?Täby initiative?, to find a partner that could implement those expansion plans. To secure a cheap basic production the partner also need to build a power plant at Hagby recycling center. Despite high interest during initial state of the process, only one procurement offer were received and Täby suspended the contract in March the following year.

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.

An Internet application, VEDAIR, for estimation of air quality in regions with small-scale combustion of bio fuel has been developed by Swedish Meteorological and Hydrological Institute with financing from Swedish Energy Agency and Swedish Environmental Protection Agency. The model contains user interface and a coupled model concept where concentrations of atmospheric pollutions are calculated for regional, urban and local contributions. In this report the model is described and a first study of air quality considering PM10 (particles with a diameter less than 10 µm) in two Swedish municipalities, Vänersborg and Gnosjö, is introduced.According to the result, there are areas with poor air quality even in smaller Swedish municipalities, mostly due to high emission from buildings with older wood heating furnace without hydraulic accumulator.In Vänersborg three areas were analysed in VEDAIR for the year 2003: Vargön, Mariedal and the downtown district. In the whole municipality the upper evaluation threshold for PM10, which is defined as 14 µg/m3 for annual average, was exceeded due to background contribution of particles. In all areas, however, the concentrations of PM10 were less than the environmental quality norms.