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.

Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.

The purpose of this thesis was to help the company Medius AB with optimization of selected parts in an existing system to minimize the execution time by implementing multithreading. The idea was to manipulate the code so that calculations could be executed at the same time. The main work in this thesis consisted of three optimizations. The first one was to reconstruct a big ?for-loop? so it would execute every loop's work in an own thread. The second optimization also was a reconstruct of a ?for-loop? so it could execute the work in different threads. The third and last optimization consisted of reconstructing a stored procedure on the database, so different parts of it each could be executed in an own thread to create data at the same time. To implement the optimizations Visual Basic .NET and its support for multithreading and connection-pools was used. The result of the optimizations meant that one of the modules could be executed more efficiently and it was 12 % faster. The other modules execution time was more efficient by 25 % faster. The meanings and requirements for this thesis are fulfilled by now letting the system make use of its resources in a better way..

Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.

The goal of this paper is to provide a model for a sustainable electricity system to an island, in the Pacific Ocean near the equator.The method which has been used is to model supply and demand of electricity in the computer program Stella, through the creation of a dynamic system that balances them against each other. The result from the model will then be used to calculate the electricity price per kWh for the island.The result of the work is that electricity from solar energy is comparable with electricity produced from oil, if the oil pays for all its external costs, and the potential for pumped hydro storage plants is located. It also requires that consumers of electricity can be their own producers to avoid the expenditure of tax and reducing the cost of distribution. But since oil is a finite resource and has had a rising cost in recent years, while solar energy has had a declining cost, perhaps this will be a more competitive solution in the future.

 This degree project aims at developing a concept for how to use solar energy to pump up water. The target audience is people living in areas where the functioning of the electricity and water network is absent. In these areas, the hand-powered water pump is the most common technology. The degree project's goal is to find an economically viable alternative to the time consuming hand-powered water pumps. The power comes from solar energy.

The sun is a huge energy source with great potential of providing energy to the heating of homes and other buildings in an environmentally sustainable manner. In order to provide buildings with energy from the sun it is necessary to transfer the energy supply over time to when the demand arises. By storing the heat in a seasonal storage, solar energy from the summer can be used in the winter when the demand for heating is greatest.Today's existing plants are mainly in Europe and particularly in Germany. These facilities are designed to supply heat demands greater than 400 MWh and covers about 40-50 % of this need which consists of energy for space heating and domestic hot water. How much of the heat demand that is covered, the solar fraction, is partly due to losses from the storage which in turn is connected to the surface area of the storage.

Local charges may induce people to change their pattern of consumption by influencing investments and acts in certain directions. Some charges could for example give people incentives to use less natural resources. This study investigates four different local charges and whether they benefit an economical management with natural resources or not. This is carried out by investigating whether there is a polarity between local charges that may influence environmental actions or goods, and effective pollution control set to achieve certain nationally determined environmental goals. The study includes two economic perspectives and investigates on the one hand whether local charges counteract governmental subsidies and on the other hand whether the charges vary between the different municipalities since large differences may lead to cost inefficiency.

In the thesis we have shown that it is possible with current technology, to buildneighborhoods that are largely self-sufficient. We have obtained some information aboutongoing work in the field of energy efficient buildings and active house which we have usedto develop a model. The feasibility study for Ranagård we have e.g been forced tofollow laws on groundwater covered, resulting in the construction of basements for singlefamilyhome is not possible. The model that we have built up overtime has been the central part of the work. The model illustrates very well what an activehouse neighborhood means and potential of such an area.

Uppsalahem is the leading housing corporation in Uppsala with its over 160 real estate properties. Uppsalahem is owned by the municipality of Uppsala, which has a climate and energy goal that aims for 100 MW of solar energy to be installed in Uppsala by 2030. The 100 MW goal, combined with Uppsalahem?s environmental policy, is a strong incentive to investigate the possibility of installing PV modules on the many available roof areas that Uppsalahem possesses. The objective of this thesis is to create a foundation for future decisions regarding PV systems for Uppsalahem.

Detta examensarbete har utförts åt företaget MH Modules AB. Företaget arbetar med att utveckla, tillverka och sälja materialhanteringsmoduler till maskin- och systembyggare utan egen produktidentitet. En materialhanteringsmodul kan bestå av rullbanor, bandtransportörer, kedjetransportörer, hissar, vinkelväxlar och pallmagasin. Syftet med arbetet var att utveckla ett nytt pallmagasin där pallar ska kunna lastas på och av på ett enkelt och driftsäkert sätt med hjälp av en handtruck.Målsättningen var att konstruera en lyftanordning med styrenhet. Efter att lyftanordningen och styrenheten var klara gjordes det en lämplig ram som uppfyller säkerhetskraven.Arbetet inleddes med att se över konkurrenternas och MH Modules egna framtagna pallmagasinen.

Uppsalahem AB is a municipally owned real estate concern that owns and administrates housing for nearly 30 000 people. The company puts a lot of effort into reducing the energy use of their housing stock. This project is a master?s thesis in the energy systems programme at Uppsala University, carried out in collaboration with Uppsalahem. The aim of this thesis is to provide energy saving measures for fourteen student housing buildings in Uppsala, Sweden.

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.

This is a report of our examination project in electronics carried out for Bofors Test Center in Karlskoga. The task was to construct an electronic devise for starting up different kinds of measuring systems in exact time during test sequences. The modules that are used today are old and unreliable. Our goal was to construct a prototype, which later on is supposed to be developed into a useful system..

World Solar Challenge är en tävling i Australien vars syfte är att främja utvecklingen av förnyelsebar energi. Här deltar olika universitet runt om i världen och för att bygga en solcellsdriven bil som drivs av solens energi. Den ska sedan köras en sträcka mellan Darwin och Adelaide på dryga 300 mil genomAustralien på kortast möjligast tid. Projektet görs för Tekniska Högskolan i Jönköping till en kommande kurs somstudenter kan söka sig till för att delta i World Solar Challenge 2013. I kursen ingår att bygga en solcellsbil som man sedan tävlar med.