Sigma energy app is a mobile application for subscribers to various energy subscriptions. The subscribers can use this mobile application to access information regarding their consumption, invoices and active subscriptions. The mobile application that was built consists of a GUI and a web API as middleman between the application and the database.                     .

In Sweden, a big part of the energy use is used in the housing sector. Political goals and targets are set up which the housing sector needs to work towards. Apartment buildings are a major part of the housing sector in Sweden and therefore reduction of energy use in these kinds of buildings are key to lower the energy use in Sweden. But there are not only political incentives to reduce the energy use. Some energy?saving measures are directly profitable and should thus be performed.

The EU has decided that it should be possible for consumers to get information about the origin of the electricity they buy. Therefore, there is a need to examine different systems for electricity disclosure. In this thesis two ways of disclosure have been studied:? Certificate system. A certificate system involves two parallel markets, one for trading electrical energy and one for trading certificates of origin.? Separated Markets.

In the year 2002 the European Union decided on a new directive according to the energy use in buildings. The outcome of this direction is a proposition from the Swedish government on the outlines of a new law in the field of energy use in buildings. The date that the law will be applied is the first of October 2006. In the future al real estate owners must be able to show an energystatement over the real estate. This project contains cooperation with HFAB a local real estate company where two buildings are analyzed according to their energystatement.

Energy efficiency is important both to reduce costs and to reduce greenhouse gas in the atmosphere. In Sweden 40 percent of the energy consumption is related to the buildings sector. Hospitals are complex buildings with different activities in the same building, which requires flexible technical systems for ventilation, heating and lightning. A quarter of the total energy consumption in Swedish hospitals is related to user activities in the hospitals. Therefore it is not only important to work with operational optimization but also to change user activities, to reduce energy consumption.The objective of this thesis was to examine the user-related energy efficiency work at two care units, at the central hospital in Sundsvall within Västernorrlands County.

This report discusses a method to detect divers in harbour environments usingpassive acoustic detection. The goal was to achieve as high detection as possiblewithout having too high false alarm rate. A short execution time was also desirable.By using the characteristic of an inhalation a band-pass filter was applied to the signalto improve the signal to noise ratio. After the filtering an energy estimation of thesignal was made. This energy estimation was later used in a frequency analysis, whichcould tell us if there were enough energy in the frequencies that correspond to adivers breathing frequency.

Geothermal energy can be extracted from an aquifer, where the groundwater is used as heatexchange medium while heat and cold are stored in the surrounding material in the aquiferand to some extent in the groundwater. Application of aquifer storage for the use ofgeothermal energy is mainly used in large scale facilities and is limited to sites with suitableaquifers in the form of ridges, sandstone and limestone aquifers.Löwenströmska hospital in the municipality of Upplands Väsby, north of Stockholm, islocated nearby the northern part of the Stockholm esker. This means that it can be profitableand environmentally beneficial for the hospital to examine the possibilities of aquifer storagein the esker material next to its property.The purpose of this master thesis has been to investigate if geothermal energy storage with aseasonal storage of heat and cold can be applied within Löwenströmska hospital?s propertyarea using groundwater modeling. A hydraulic groundwater model was constructed inMODFLOW based on a simplified conceptual model of the groundwater system.

Efficient energy use in restaurantsUmeå Municipality wishes to combine energy issues with food control, and thus help restaurants to become more energy efficient. During March and April 2010, I visited seven restaurants and interviewed restaurant personnel about current state and application of kitchen appliances, using a checklist to make sure that the same questions were asked at all restaurants. The restaurants were all different sizes and offered different kinds of food. The study mostly focuses on energy efficiency by behaviour and not on location or technology. Almost every restaurant that was visited had the potential to improve in one or more areas, such as kitchen appliances, lamps and lighting fixtures, heating, cooling and ventilation.

The assignment is issued by Scania Maintence AB seeking a new approach to detect power changes in their industrial processes. The work has taken place at Ångströmslaboratoriet and tests have been performed at Scania AB Södertälje.Today?s society consumes enormous amount of energy. In both economically and environmental view, it is important that the processes are effective, with high power factor. There are many ways to measure power in the industry, what they all have in common is that the installation is advanced, requires time and planning.

There is always a need for more effective ways to store energy in order to reduce the human impact on the environment. One step on the way can be the use of flywheels as kinetic energy storage devices. Low frictional losses are essential for a flywheel to be effective. To minimize these losses active magnetic bearings (AMB) can be used to keep the shaft centered instead of the more conventional ball-bearings. AMBs use actuators and a fast control system that needs correct and noise-free measurement data of the shaft position and the current in the actuators to work properly.This thesis explains the process of constructing power electronics and a current measurement system for active magnetic bearings (AMB).

This thesis investigates how energy is used in three public baths today and suggests measures that could reduce the energy demand. The results show that there is a great poteltial for energy savings i public baths, and that it would be interesting to examine some of the proposed measures further..

This thesis concerns an energy audit of a food industry. The company's business consists of boiling and peeling shrimps, and producing mayonnaise-based salads. This type of work involves energy-intensive processes, such as steam generation, compression of air and refrigeration of large spaces. These needs are supplied with electricity. Furthermore, the industry is a major consumer of district heating, particularly for heating the supply air in the ventilation system.

The Swedish building and property management sector are responsible for about 30 % of the total energy use. In order to take environmental consideration, different environmental assessment tools and standards are used. Miljo?byggnad, Svanen, FEBY12 and PHI are some of these. There has been increased interest to certify buildings and therefore it is of interest to evaluate the assessment of the energy field to see if relevant energy aspects are assessed.

Wind power in Sweden is expanding in response to the government's decision that 49% of Sweden's power should originate from renewable energy sources by the year 2020. Problems with noise and sound emissions related to wind turbines are a constant argument against the wind power expansion and this paper means to examine if vertical axis wind turbines might be a viable alternative to the conventional horizontal design for noise sensitive areas. In order to determine factors like difference in frequency, noise propagation and noise emission level, measurements of both horizontal and vertical axis wind turbines have been completed and the data analyzed with MATLAB. It is shown that there is a difference in how the noise from the two types of turbines propagates due to avariation in the frequency spectra of the emitted sound. It is also shown that vertical axis wind turbines generate a lower sound emission with less intensity inthe lower frequencies..

This master?s degree project concerns the combination of a multi dwelling passive house with solar energy for the generation of electricity and domestic hot water (DHW). Different alternatives with either solar thermal systems or photovoltaic (PV) systems are compared with two reference alternatives producing DHW from electricity or district heating. The economical comparison uses a life cycle cost (LCC) perspective based on the present value of expenditures for investment, energy and annual operating and maintenance.The energy yields from the solar energy systems were calculated by hand and with simulation software. Calculation and dimensioning of PV systems were carried out with a software called PVSYST.