The urban heat island is an area restricted to a city center where the temperatureis higher than its surrounding environment. The greatest temperature difference isfound at night when the weather is calm and the sky is clear of clouds. There are twomajor causes behind this phenomena and the first one is the use of energy forheating of houses. The heat leaks through the walls of the buildings and warms upthe surrounding mass of air. The second one is the use of building material whichstore the suns radiation on daytime and releases the heat during night.

The purpose of this report is to investigate the possibilities with drain water heat recovery (DWHR) in residential buildings. Information and relevant theory has been collected and summarized in this report. Calculations have been done for given scenarios to evaluate profits. DWHR heat exchangers use simple technology and have long life-time. The heat exchanger is connected to outgoing drainage pipe and incoming cold-water supply so countercurrent flow is accomplished.

Gunsta is situated about 10 km east of Uppsala. Today there are plans to establish 1000 new households in Gunsta before year 2030. The required energy for heating houses and water would be distributed via a district heating system, which also includes 200 existing residences. The annual required energy, according to this study, would be 16.2 GWh with a maximal peak effect of 6.9 MW. To meet this need, the study suggests a system with heat pumps to upgrade the 31?C water from a 1.8 kilometre deep borehole.

The sound part is mainly practical and is dependent on concepts that have been tested through measuring with a sound level meter. The design part is more theoretical and has been verified with CAD models and finite element analysis.With a sound damping hood on the compressor the sound level is reduced with up to four dB. An optimized absorbent for the compressor space gives a reduction with three dB. By using the insulation for the heat water tank as absorbent we can see a sound reduction on the lover octave bands. A reduction like this is elsewhere hard to achieve as at it requires thick absorbents.By changing the today?s insulation to the heat water tank to a form of polystyrene polymer insulation the weight from the heat pump above can be transferred to the stable heat water tank.

Göteborg Energi has a surplus of district heating during spring, summer and fall. The heat surplus is due to a constant production of waste heat from oil refineries and heat from waste incineration over the year. It would be desirable to increase the demand for heat and the uptime for the newly built combined heat and power generation plant, Rya Kraftvärmeverk. One alternative could be to integrate Rya Kraftvärmeverk with a pellet production facility. By producing heat, electricity and pellet in a joint process the energy use can be decreased.

SAPA´s resource of waste heat is the basis for this thesis to investigate the possibility of energy assets in their cooling water and possible uses for it. The energy in the waste water is greater than the current need which has three uses which are (1) heating the factory, (2) converting liquid propane to propane gas and (3) local domestic heating. The average energy load that is available is 1, 7 MW and the average temperature in the cooling water is 41°C. The total energy load at dimensioning out side temperature is approximately 1,6 MW for the three current uses. The temperature is currently too low to be used directly in the existing systems so an upgrade is needed.

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.

My questions at issue for this report has it´s beginning in the growing problems of thenegative effects of burning fossile fuels and the rapidly growing energyprices.1. Is it possible to design a micro scale powerplant?2. Is it economically interesting for a potential customer to by such a product?The aim with this report is therefor, with the help of design work and calculations, to answerthese questions and to create a platform for building a fully functional micro scale powerplant.The material used in the report is mostly product catalogs from various industries but alsostudy course littrature about steam engines.The result of the report is that it is fully possible to design a fully functional micro scalepower plant.

The purpose of the study was to investigate the use and losses of energy in an existing older building. Another purpose was also to look through various options for heating systems with renewable energy in the building. The aim was to reduce the use and losses of energy. The first step was to study the related electricity bills of the building and also perform measurements and calculations of the building envelope and ventilation. The next step was to find out the possible actions for energy saving by performing measurements and calculations.

In order to reach the environmental targets, set up by the EU, there are many measures taken to make Sweden more energy efficient. In the housing and real estate sector, an installation of an exhaust air heat pump that reuses the heat in the exhaust air in order to lower the amount of acquired energy, is an example of such an action. The recovered energy can then be used for heating of radiators and tap water. This report aims to evaluate and compare three different systems using exhaust air heat pumps regarding COP, degree of coverage and cost savings. This study was delimited to only account for apartment buildings.The theory chapter describes the different conditions and factors that affect a building?s energy balance.

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.

En hanteringsutrustning för att underlätta förberedelser av gips på sjukhus.

Glass has sophisticated front properties and are used as facades in high buildings. During cold periods, these glass facades could cause thermal discomfort, due to cold downdraught. Cold downdraught can be countered by placing heaters under glass surfaces. Nowadays technology offers highly insulating windows, which is why there is an interest to investigate the indoor climate with only underfloor heating. The research in this area is limited, and few empirical methods are available.

The thesis describes a completely new biofuel system to generate particle-free heat from combustion of ash-containing biofuel particles at high temperatures.The suggested system gives opportunities to introduce biofuels in new areas.Main components in the suggested system is a heat radiating combustion chamber intended for pulverized wood, combined with regenerators to extract heat from flue gases and simultaneously preheating the combustion air.The thesis contains a description of the suggested system, theoretical considerations, calculations regarding the combustion, and includes results from tests performed.The results from calculations and tests performed concludes that the system is workable and possible to apply..

When planning new wind farms, the cost for the internal electrical grid is estimated to account for 8-9 % of the total investment cost. On top of that, the cost for accumulated reduced income over several years (due to electrical losses), has to be added. The economic lifespan is relatively long (about 20 years) which means that an error in the loss calculation could lead to a bad decision basis. The accumulated reduced incomes due to electrical losses can be higher than the initial investment cost for the internal electrical grid.Today, Statkraft Sweden is using a template number when estimating the electrical losses in a wind farm. The actual losses are probably lower than the template number which could lead to an unnecessary high loss cost when planning a new wind farm.The aim of this M.Sc.