Increased energy consumption in the world has created an increased supply of various fuels, especially fossil fuels. The Swedish government has set up various energy targets for 2020. To reach these goals it?s important to increase the energy efficiency in local buildings such as schools. This work illustrates the breakdown between energy supply and Energy losses over the school.

Calculated and measured energy in residential buildings is going to differ. The reason to this may be due to many factors. In this study there is a study on how these factors affect the energy use in a building. To get an insight in what defines energy, there is first a description of energy supply both worldwide and used in Sweden, followed by a description of the energy balance. In this study energy will be studied in residential buildings only.

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.

To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock.The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air.

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.

This report will show the energy usage of Hotel Princess in Sandviken, Sweden. When the hotel changed owner an examination of the hotels heating, ventilation and sanitary systems were done. The report showed flaws in the ventilation system, and is why the new owner wanted a closer look at the energy use of the hotel. The original building was built in the 1930s and two major extensions have been built, one in the 1950s and the most recent in the 1980s. An assumption made is that the building parts were built to the restrictions during the time. Activities on the hotel include sleep over, conference, night club, massage and swimming in the hotels pool section.

In this report the balconies? abutments for a property in Bo01-area in Malmö has been studied. The property which is called Vitruvius contains four build-ings where two of them have corbelling balconies with intermittent abutments. With intermittent abutment means that the 50 mm thermal bridge insulation that the balconies is equipped with, is broken regularly by a 300 mm concrete heel. The reinforcement bar that holds the balcony runs through this heel.

An important process for grid companies in order to reduce power losses in electricity distribution grids is to figure out where and how they appear. This report describes the factors that cause power losses in low voltage distribution grids and methods for how they could be measured and analyzed. Measurement data for consumed and injected energy were collected for twelve low voltage distribution grids owned by Gävle Energi AB in order to analyze the size of the power losses and how the measurement uncertainty affects the collected data. Then models of three of the grids were created in MATLAB in order to analyze the data and the power losses were calculated to be compared to the collected data. Curve fitting were also used as a method in order to analyze the power losses from collected data.The results show that the losses in the studied grids are low.

Energy losses are an essential part of a power grid company?s costs. From anenvironmental and economic perspective, it is important to reduce these costs. Toknow where efforts should be deployed, it is important to have good knowledge ofwhere in the network losses are situated. When creating network tariffs, there is alsonecessary to have a correct distribution such that the network customers that use acertain part of the network, only pays for the network losses in this area.

This thesis has been carried out on behalf of IV Produkt AB and intends to set an average ratio of thermal Energy losses in apartment buildings that were built during the 1960-1990. This shall be derived by analyzing the total district energy consumption that has been divided into three parts: heat Energy losses (the actual heating requirements), the heating of domestic hot water and heating energy consumption for the controlled ventilation.Three different residential areas that were built during the years 1962-1966 and one that was built in 1993 has been analyzed. All residential areas are located in Växjö urban and contains between four and six apartment buildings.The analyzed objects have a mechanical exhaust ventilation systems and district heating as the heating method. No own laboratory work or experiments have been done in this thesis, the calculations have been done on the basis of parameters from VEAB, interviews with property managers, and literature studies. By calculations, we have got a result that is reported in Chapter 6.

Umeå Energi are working towards a goal, that in the year of 2018, they will be completely climate neutral. As a part of this, one target is to reduce their grid losses by 4 % of the 2012 level, which corresponds to an overall reduction of the grid losses of just over 1.7 GWh. In many residential areas, the distribution grid is designed and rated for electric heating as the heating in the houses. As many of the houses later has been converted to other types of heating, their electricity use has decreased and the total power output from many of the secondary substations has decreased significantly. Because of this, many of these stations today are well oversized, which in turn means that the Energy losses in these stations are unnecessarily high.In this degree project, 25 secondary substations have been studied, all located in residential areas in and around central Umeå.

AbstractEmbla 5 is an office building which has done a large improvement. The clients of this building has made an order of WSP and the student Anders Kempe to calculate the use of energy for the building, and after that result proposing further measures which can decrease the energy use of Embla 5.The ground for this report is when calculation of the present energy use of the building is stated. To make that information of a number of parameters such as envelope, the heating system and ventilation has been located and set in to the simulation program IDA ICE which calculate the energy use.To improve the energy use further this project has been concentrated to change the system of ventilation. Today the ventilation system is of the kind CAV (constant air volume) and the air flow is dimensioned for after recommendations from BBR and Arbetsmiljöverket in the office spaces. Consider that Embla 5  is an office building where the people only staying for 8-10 hours/day so was the ide to see how much energy saving if the air flow is reduced the time people not being in the building.

This diploma work has been carried out in collaboration with the building contractor Sh Bygg Fastighetsutveckling AB in Uppsala with the intention to investigate how the height of a building affects various energy aspects such as transmission losses, infiltration, and the specific energy usage. Three different reference objects have been studied. The reference objects have been simulated for four different heights in the calculation program VIP-Energy.The results show that an increase in floor number can lead to both advantages and disadvantages. As the number of floors increases, transmission losses per square meter floor area decreases. However, as the height of the building increases, the reduction rate decreases.

The technological legacy from the early electrification of the Swedish railroads has resulted in a power grid with a lower grid frequency than the national power grid from which it is fed. Energy transfer between these power grids with different frequencies requires substations, adapting the grid frequency for the rail road power grid. For this purpose, a feeding power grid has been built, stretching across the country from Boden in the north to Tälle/Häggvik in the south.Power transfer in the Swedish power grid results in voltage angle differences which increase with increasing loads and transfer distance. These voltage angle differences are transferred from the power feeding substations to the rail road power grid, will in some extent cause loss of energy due to unwanted power flows from north to south.To minimize the losses due to this phenomenon, a power management system called EFS 132 kV has been developed and implemented. The system minimizes the unwanted power flows and controls the desired power flow for a good distribution of loads between the power feeding substations.This thesis investigates the extent of the transmission losses avoided due to the EFS 132 kV that coordinates the idling angles to a common reference point.The results indicate that EFS 132 kV affects the power flow, especially between the northern substations through an improved load distribution.

In Sweden the climate makes it impossible to feed fresh herbage to cattle during many months of the year. During periods when preserved forage must be supplied it is important that this forage is stored in such a way that high quality is retained, both nutritionally and hygienically. Furthermore, it is essential that losses occurring when handling and storing the forage are kept as low as possible. This study compares storage in tower silos, bunker silos, big bags and bales,estimating dry matter losses as well as losses in metabolizable energy and crude protein that occur during storage. The results show that tower silos, bunker silos and big bags, the systems with the largest amount of forage and a long feed out period involve larger losses than bales, which are fed out immediately after being opened. As the feed out rate influences the losses, tower silos and bunker silos should be used during the period of the year when the feed out rate is as high as possible, i.e.