This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

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.

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.

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

In modern society in terms of economics and environmental impact, it is important to ensure that a company is as energy efficient as possible to reduce the amount of energy used. About 10 TWh of electricity used annually to pump drives in Swedish industry. Therefore, pumping system has great potential for energy savings.The objective of this report was to determine how much energy and money that can be saved with the insertion of variable speed drive to six pumps on Bleach plant 4 in Skutskär Mill. The work was performed with electrical measurements during one week, analysis of pump curves and the compilation of production data over a year.The results show that four of these six pumps were profitable and yielded an annual saving of 1172 MWh of electricity and 560 000 SEK. With an economic lifetime of 10 years and a discount rate of 6.8% the final result for the entire life-cycle savings became 3 355 000 SEK.

The purpose with this report is to examine how the implemented energy efficiency measures on Bokelundskolan in Växjö have had impact on the energy use. The measures which have been implemented are, new ventilation system, new heating system, optimized adjustment of the heating system, new windows with U-value 1.2 and lower window height, insulation under windows and in the crawl space. The school's energy use before and after rebuilding has been calculated with the calculation program, Vip-Energy 1.5.5.Calculations of energy use for the school with windows on U-value, 0.9 and 0.7 have also been done. The replacement of windows has been studied from a cost perspective. The conclusion is that the exchange of heat and ventilation system was the biggest contributor to reduced energy use on Bokelundskolan.

During the last decennium climate issues have become more and more important. Many steps towards an adaption of efficient energy supply systems have been taken all around the world. These steps have been created to ensure the next generation?s energy demand. In EU and Sweden objectives have been set to ensure that the energy consumption decreases by 20% year 2020 and by 50% year 2050 compared with the energy consumption levels of year 1995.

In today?s society there is an increasing demand for renewable energy sources such as sun and wind power. These sources are intermittent, and energy storage is therefore needed to ensure a constant power supply. This report compares pumped hydro energy storage (PHES), compressed air energy storage (CAES), flywheels, batteries, super magnetic energy storage (SMES) and hydrogen energy storage.The opportunities for further development are limited for PHES and CAES in comparison with the other technologies. Lithium-ion batteries and hydrogen energy storage are considered to have the most potential in the future.

Energy awareness is growing among the Swedish population and a one­?to­?two-family dwelling can save energy. The purpose of this paper is to design a tool that helps these home owners reduce their energy costs.The paper develops a model that gives them an indication of how much energy they can save. For the majority of homeowners, the next step in the quest to reduce theirs is most likely an energy audit. Therefore, information to help home owners to get a good energy audit performed is included in the model.A prototype running the operating system iOS is created and validated against existing models, as well as an energy audit. .

To build a sustainable future should we first understand that; every aspect of our daily lives can affect the environment. It?s important that we take responsibility for understanding how we impact the environment and change our actions accordingly. The worlds total energy consumption equivalent to 80 million MWh / year. This corresponds to about 220 million MWh / day.Energy consumption is one of the main reasons for increased greenhouse gases when the reduction of this consumption has a great demand worldwide.In order to prevent the energy that consumed the buildings must be energy efficient but there is a conflict between radon ventilation and energy conservation in a building, given that ventilation can consume as much energy (currently 29-59% of energy-efficient houses use), especially in a cold climate as in Norway.

The purpose of this study was to implement an energy analysis and environmental evaluation of the property Hemsta 12:16 in Gävle. Based on two different methods, Energy Balance calculation and Environmental Building, the result of the property's energy use, energy performance and environmental impacts are presented. Except that, measures to reduce final energy consumption are presented.      The proposed measures can reduce energy usage by 100 400 kWh / year, which represents a decrease of 18% of the present energy usage. This would represent a total savings of 63 000 SEK per year. In addition, the environmental performance is improved by adopting the suggested measures..

The question of excessive global energy use needs to be solved. All energy production and usage have negative environmental impacts, which are best solved by reducing energy consumption and by using energy more efficiently. A large part of the Swedish energy use is concentrated to the building sector and to reduce the total energy consumption real efforts need to be made to make buildings more energy efficient.The aim of this study was to investigate how energy is used in one of Göteborg University?s buildings and to find measures that can be taken to improve its energy efficiency. The chosen building Zoologen, is used for research and education.The main method of the study is computer simulations of the present building and of possible energy reducing measures to be made in the future.

The construction industry has demands on energy use in permanent buildings. How much energy that is permitted to use during the time the building is produced has no requirements. The purpose with this study is to learn how far Skanska has come with the work of making the building site more energy efficient.A literature study has been performed in the beginning of the study to survey what energy efficient arrangements that can be applied and how they operate. Using site visits and interviews the situations on the building sites have been studied as well as the energy efficient measure that are in use.Skanska has come a long way with the work of energy efficient building sites and they keep improving. They have improved half of their cabins so they use 50 % less energy.