The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an Electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

To be able to secure a safe and reliable power supply is becoming increasingly important since society depends on services and functions that need continuous power supply. The delivery rate in Swedish power supply is 99.98 % which insists on a high availability. During the past decade several storms has passed Sweden which resulted in large amount of tree felling leading to extended power outages. During these storms many socially critical activities, such as electric utility company Fortum, experienced disruption in mobile communication which affected the crisis management. This paper has investigated Swedish mobile operators? crisis management at Hi3G, Tele2 and TeliaSonera with a case study of the storm Dagmar that hit Sweden during December in 2011.

The aim of this study is to examine possibilities and barriers for an introduction of electric vehicles in Sweden. The study has an interdisciplinary approach and thoroughly examines the essential topics which influence the future of the electric vehicle. The study reaches from answering the question on why electric vehicles lost the game to petrol cars in the early 20th century, to sketch how the difference in total cost of ownership will be between electric vehicles and petrol cars for the coming 20 years. Apart from these subjects the main topics of the study are today?s and tomorrow?s situation regarding technology, charging, fuel, market and economic incentives from an electric vehicle perspective.

The purpose of this study is to investigate how much of the estimated annual electric energy production from Swedish wind power that actually was produced, as well as the history of this agreement over time. The aim is to also examine if there are properties that have caused some group of wind power plants to produce more or less, compared to their estimated production. Operational data on wind turbines collected by the Swedish Energy Agency was analyzed. A survey was made among owners of wind power plants with a nominal power of at least 2 MW. Two different methods for normal year correction of production data were used and compared.

The present study concerns a concept development of a product idea that Bengt Magnuson, associate professor, had when a heavy storm caused a widespread power failure of long duration. With a basic power-producing unit one should be able to get through a power loss. The product could also be useful for other tasks if different modules are connected, e g grass mower or snow-blower.According to the product idea the basic unit will be able to produce Electric power enough for a fridge, freezer, TV, and a few electric lamps. Normally the basic unit can be used e g as a mower, when such a module is attached. An increased number of tasks would make the contraption useful and tempting for those who do not own an electrical power set in reserve.

Distributed, renewable generation-units and more efficient use of Electric power,demands a developed electric grid. This grid is often referred to as the ?Smart Grid?.This future electric system rise expectations among actors in the existing electricmarket. International organizations share visions of opportunities for electricityconsumers and new actors, ready to enter the market. At the same time, electricutility companies may question the need for some of these upcoming changes, as theyare sometimes expected to lead the development.This paper therefore seeks to investigate the business opportunities related to SmartGrids.

This thesis was carried out at Atlas Copco Tools and Assembly Systems. The purpose hasbeen to develop a design tool to be used for development of new electric motors for AtlasCopcos electric nutrunners. The focus of the thesis has been to increase productivity bydecreasing the power losses in an electric tool. The productivity is defined as themaximum number of tightenings a nutrunner can perform without becoming too hot.Before starting the development of this design tool an existing Matlab script, whichcalculates the losses in a slotless electric motor, has been studied and modified torepresent the real losses in a better way. The modification has been made by performingpractical studies of different losses and then adjusting existing parameters in the Matlabscript.Because design changes in one part of a mechatronic system can lead to a decrease inperformance of another part the choice of parameters that can be changed has been madeso that other parts of the system is affected as little as possible.A study of the existing tools efficiency during an entire tightening has been made toincrease the understanding of when and where the different losses appear and to comparethe modified Matlab script with the measured values.The design tool was formed so that it executes the Matlab script, that calculates thelosses, for a number of different design options and stores the alternative which producesthe least losses.

Most of the portable electronic devices use a battery as a primary power source. Nowadays, when the applications are becoming smaller and smaller and more power efficient, the designer needs to concentrate more on reducing power consumption, using secondary power sources and introducing power storage devices. Multiple power source availability and a power storage device on the board will make the applications much more useful and efficient in everyday use. This thesis proposes a power supply unit (PSU) for wireless sensor platforms which is capable of supplying a sensor node with energy from multiple sources, as well as status information from the PSU. Present power storage devices, like electric double-layer capacitors (EDLCs) and batteries, have become more and more common as their characteristics have developed.

The assignment given to us by NCC was to compose a degree project based on ground excavations for power cables. The aim of the study was to examine suitable excavation methods depending on different possible terrain conditions. The amount of previously written material within this subject is nearly non- existent and therefore there is a genuine interest by the NCC to receive a compilation of different production methods. The greater part of this study is based upon interviews with several companies active within this area of expertise. The technique of placing the electricity grid beneath ground for safety is today getting more and more common.

The Island of Öland has one of the best wind climates for land based wind power in Sweden. An objective for the Island is to become self sufficient using electricity from renewable source of energy such as wind. There is currently 55 MW capacity installed on the Island and it is estimated that grid congestion will occasionally occur if more than 135 MW was installed.The aim of this thesis is to investigate he possibilities for load management by smart charging of electric vehicles, EV. The definition of smart charging is that the charging is done to some extent with an ICT-system, (information and communication technology) that correlates wind electricity generation to the charging of electric vehicles. The purpose is to avoid grid congestions on the sub-sea cable that connects Öland to the mainland because that in turn would curtail wind energy production.

Tumble dryers and drying cabinets have to a large extent replaced the traditional way of drying clothes outdoors. They are faster, more convenient, require less space and can be operated regardless of weather conditions. This replacement has significantly increased residential energy consumption, due to the fact that tumbles dryers consume large amounts of electrical energy. In the USA 9 % of the households electric energy is consumed when drying clothes. Over 4 million tumble dryers are sold in Europe each year and 20 % of the residential electricity consumption in Sweden is used drying and washing clothes.

I have in my thesis, examined the possibilities in terms of energy for a condominium association.To have an effective and good energy is becoming increasingly important with today's rising electric and oil prices. In my thesis I have used the condominium association Kärralyckan, which is situated in Falkenberg. The buildings at Kärralyckan are built in the mid-1970s, and are heated by electric radiators. The tap water is heated by an electric boiler.Based on that calculation I can show the various energyststem. The different solutions have been developed by contact manufacturers and installers through phone calls and e-mail.According to the results shows that geothermal heating has been a great solution for Kärralyckan.

The electric car has existed for over a century and producers has tried to commercialize it earlier but has not succeeded. In recent years, however, a change occurred that may be significant for the electric car and it is now to commercialize in the market of passenger cars. The technology has in recent years elaborated as more car manufacturers have started to invest in development in the subject field. This thesis aims to compile an action plan for the development of charging infrastructure for electric vehicles in Uppsalahem ABs residential areas. It is based on a survey of different residential areas and a survey of charging infrastructure.

Hydropower is the largest renewable energy source available in today's society. Operation and production is handled by high-tech electronics. This thesis is done on behalf of Statkraft Sweden AB who wants to explore the possibility of replacing the hydraulic cylinder with an electric actuator, generally as well as a case of a small power station on the river Nissan. Whether it is the chaplain or francis turbine vanes are actuated by hydraulic cylinders. Because of Gustavsberg hydropower is inconstant operation, this report is based on power calculations, which are read and computed according to the available hydraulic diagram.

Jämtkraft AB which is a power production company in Sweden has bought two newhydro power units to their station in Hissmofors. The two new generators are using aconcept with sliding stator feet to handle the thermal expansion.The concept with sliding stator feet on hydro electric generators has not beenworking satisfactory on many hydro power stations in Sweden and has caused a lot ofcosts due to long downtimes.The new station in Hissmofors is very important for Jämtkraft AB, and therefore theywant to know how to make sure that the sliding stator feet are working as theyshould. According to theories and a simplified model of the generator the stator feetdisplacement should be around 1 -1,6 mm.The generators are delivered with a surveillance system that will measure thedisplacement of the sliding stator feet. The signal from the system isn?t accessible forJämtkraft AB but it will alarm when the sliding stator feet are malfunctioning.To secure the function of the sliding feet a logger for the surveillance system or adifferent measurement system must be used; if both systems are used Jämtkraft cansecure the function of the surveillance system..