Climate and environmental issues is now high on the agenda. We live in a generation that must try to solve some major environmental problems. Buildings and habitations account for approximately 40 % of Sweden's total energy today. To reduce this figure, as needed, more research in the field of energy efficiency is required.This thesis concerns the heating of buildings. The load on district heating is heavy during certain times of the day.

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.

At the Division of Electricity at UppsalaUniversitythere are ongoing researches, including a research concerning turbo generators.Turbo generators produce a large share of electricity in the world; however they are costly mainly due to the fact that the cooling and ventilation that are needed to eliminate the excess heat from the generators are expensive. Turbo generators work with high efficiency and in this project, the main task is to simulate a generator while taking into account that the generator must be designed against self-oscillation, centrifugal force, exhaustion and heat. The turbo generator must be simulated without being too expensive and complicated.In this project, the dimensions of the turbo generator depend on the efficiency of it, and where the losses are in the generator. Furthermore, the optimum values need to be chosen with the help of the ACE simulation program. The report begins with an introduction describing the project followed by a task description that is dealing with the project.

There are several energy systems in the Swedish society and to ensure the comfort and health of the citizens it is of importance that the different energy systems are functioning properly. District heating is one of these energy systems and many household depend only on district heating to warm up their homes. District heating is dependent on several processes where every step needs to function in order to deliver the produced heat to the end consumer. Previous studies have investigated the distribution of district heating and how to make customers choose district heating as their heating method. The supply of fuel to the district heating plant has not been studied as much, even though it is an important part of the whole system. This thesis is a part of the project NORD-STAR (Nordic Strategic Adaption Research), which has focused on climate adaption in the Nordic countries.

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.

Detta examensarbete handlar om utveckling och konstruktion av ett spjäll och spjällblad till en plattvärmeväxlare som ingår i Fläkt Woods AB:s produktsortiment.Bakgrunden till utvecklingen berodde på två problem med det nuvarande spjället. Ett problem var att det fanns vissa hygienproblem med befintlig konstruktion som behövde rättas till och ersättas mot en bättre lösning. Detta för att produkten ska kunna certifieras enligt normen VDI 6022. Det andra problemet var att den befintliga konstruktionen kändes gammal och behövde förbättras.Examensarbetet omfattar två stycken huvuddelar/mål. Den första delen är att finna ett material för att kunna täta i spjället på ett effektivt sätt.

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 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.

District heating covers most of the residential areas and industries in the twoneighbouring Swedish municipalities Nyköping and Oxelösund. In Nyköping,Vattenfall AB Värme produces heat in a bio-fuelled CHP plant. In Oxelösund,waste heat and use of waste gases from the steel production at SSABOxelösund is the basis in the district heating system.This report examines the environmental consequences of a connection betweenthe two district heating systems. A broad system approach is used and the focusis on environmental effects in the system.A system analysis has been performed on the result of simulations of differentheat and electricity production alternatives. The alternatives simulated wereone where Vattenfall Nyköping covers the base load in the joint district heatingsystem and two where the power plant at SSAB Oxelösund supplies the heatbase load.The conclusion in this report is that the consequences of connecting the twodistrict heating systems can be both positive and negative, depending onsystem boundaries and on the environmental focus.

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.

In today?s society climate change has grown to one of the largest global issues. To reduce emissions of greenhouse gases, large changes of the energy system are required. An increasingly popular solution is investments in local production of renewable energy resources like wind, solar or geothermal power. The following report examines the possibility for implementing a solar power plant on the new hospital Nya Karolinska Solna. Two different technologies for extraction of solar energy has been studied, solar thermal collectors  to meet the need of heating and solar cells to satisfy the need for electricity linked to operating the hospital building.

Sweden is a country that has made some progress in developing energy efficient solutions. The problem in Sweden is that many houses and apartment buildings are old and have inefficient ventilation- and heating systems. This energy is lost when systems are inefficient, which then results in huge economic costs. Luckily, more and more people are becoming aware of this, which means that Sweden is on track to become even better within energy efficiency.Energy use for the housing- and service sector amounts to 166 TWh of total use at 616 TWh. Without distribution and conversion losses, these figures show that the housing- and service sector accounts for almost 40 % of the country's total energy consumption.

The demand for environmental assessments on buildings and energy consumption is increasing as well as the energy performance requirements for buildings. At the same time it is increasingly common with self-producers of heat and electricity generation.The main purpose with this master thesis is to investigate how time resolution affects the environmental assessment of energy consumption in office buildings connected to district heating (DH). Environmental assessments were done with both attributional LCA and consequential LCA with system expansion.Fortum´s DH system in Stockholm was analyzed and district heating production was simulated in a Matlab-model. Greenhouse gas (GHG) emissions for the production were calculated. The heat demand of the office Gångaren 16 in Stockholm was simulated in IDA ICE.