Biogas is a renewable energy produced through anaerobic digestion, which means that organic matter is degraded by microorganisms under anaerobic conditions. The produced biogas can then be used for cogeneration, electricity, heat or upgraded to vehicle gas. Eskilstuna Energy & Environment AB has four digesters at Ekeby water sewage treatment plant, Eskilstuna. One of the biogas reactor (RK4) is equipped with a jet-mixing system while the remaining digester uses top-mixing. The mixing system is an important parameter to achieve optimum operating conditions for the process regarding gas production and degree of digestion.

Syftet med denna studie var att undersöka uppfattningarna hos karaktärsämneslärarna på gymnasiet med inriktning mot El-programmet, elektronik/datorteknik vad gäller de arbetsuppgifter som de utför inom karaktärsämnet, hur förberedda de menar sig vara för dessa uppgifter, samt i vad mån de anser sig behöva utveckla sin kompetens. Vidare var syftet att ta reda på vilken kompetensutveckling som erbjuds för dessa arbetsuppgifter. Studien bygger, utifrån frågeställningen i syftet, på en kvalitativ undersökning med hjälp av intervjuer. Intervjuerna genomfördes med sex karaktärsämneslärare inom avsedda program fördelat på fyra gymnasieskolor i fyra olika orter.Resultatet visar att samtliga intervjuade känner sig kompetenta i sitt verksamma karaktärsområde i och med att de har både relevant utbildning och arbetslivserfarenhet. Men de flesta utför helst inte frivilligt det administrativa arbetet utan de vill ägna sin tid åt den tekniska delen som intresserar dem mest.

Passive houses are a relatively new concept in Sweden and by that it is meant a house without a traditional heating system. The most acknowledged passive house project is the terrace houses in Lindås, Gothenburg, which we have used as a reference. This project concerns a square apartment block. So far, no square apartment block has been built as a passive house in Sweden.The common opinion in the construction industry is that it is not economical to build extremely energy efficient houses. With Peab as commissioner our task was to investigate if that is true, if regarding the construction of a multi storey house as a passive houseMidroc, now owned by Peab, constructed in the block of Preussen in Jönköping during 2004-2005 four houses, with 132 apartments distributed on seven floors.

To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.

The object of the thesis is to propose a new lighting plan for the square Fyristorg in Uppsala, and to describe the process which have led to it. It all started when I choosed the place together with the municipality of Uppsala. I have been doing research and analyzed how the place and it´s existing lighting works both during different times of the day and also in the evening. After researching the place and it´s existing lighting I´ve decided to put up the following goals fot the new lighting design. 1. The general light level of the place shall be experienced as higher than today. 2. The light level of the place shall be adapted to the light levels of surrounding places. 3. The lighting shall be free from glare. 4. The lighting shall be adapted to people passing by. 5.The lighting shall be adapted to the surrounding architecture. 6.

Companies today are expected to communicate their responsibility to the world around them. Society?s expectations differ and stakeholders are demanding that companies act responsibly on matters related to climate, work environment and human rights. The purpose of sustainability reports is that companies should measure, present and take responsibility in relation to their internal and external stakeholders. It is intended that a reasonable picture of the company's sustainability performance should be communicated, containing both positive and negative effects.Companies efforts with sustainability issues is industry-dependent and industries with significant environmental problems perform the most advanced environmental statement.

Through our study we have found that there are moresimilarities than differences in leadership styles. The dominant leadership style of managers in both private and public sector is the democratic leadership style, often in combination with other styles; most notably the authoritarian leadership style. The charismatic leadership style doesn't seem to be popular in neither private nor public sector.Title:                                                                              A study of leadership styles in public and private sector Course:                                                    Bachelor Dissertation - LeadershipAuthors:                                                  Milos Kostic and Rudina ShabaniAdvisor:                                                   Ingemar WictorKeyword:                                                Leadership style, public, private, leadershipProblem formulation:          What differences and similarities in leadership styles are there between managers in private companies and managers in public companies?Purpose:                                                  Our purpose has been to find which similarities and differences there are in leadership styles between managers in private sector and managers in public sector.Theoretical framework:       After studying the theory of leadership, we found four different leadership styles relevant to our study. In the theoretical framework we discuss theories of authoritarian leadership, democratic leadership, laissez-faire leadership and charismatic leadership.

Biogas mainly consists of methane and carbon dioxide, where methane is theenergy-rich gas, and is naturally created when organic matter breaks down in absenceof oxygen, also known as anaerobic digestion. A biogas plant re-creates the anaerobicconditions inside a digester where the organic substrate is fed into and digests toproduce biogas. The gas is then used to produce energy by combustion and can beseen as a completely renewable fuel.Today, energy from biogas is used primarily by major stakeholders such asmunicipalities and thus the plants become very large with high investment- andconstruction costs. There are currently few small plants in Sweden, even though thepotential for agriculture and medium-sized to smaller farms to become self-sufficientin terms of electricity and heat is great. Farms have a natural stock of digestibleorganic material in form of manure or crops for example, which are constantlyavailable.

To provide our company a new business opportunity I have in this essay examined the economical possibilities to sell energy. I have chosen to do a case study on my own farm in this essay. The farm is focused to cropping and also have some properties for hire. The farm is situated in the village of Fjelie and that?s where the opportunity for selling heat are. Fjelie has about forty houses. The idea is to build a plant where straw is being used as fuel.

In this report a study has been done regarding different heating systems on which are the mostcomprehensive with solar heating systems. The report has also been focusing if solar power can beused as a primary heating source for supplying more than 50 % of the buildings total heatingproduction. The University of Dalarna constructed a demo-house for this purpose and according tocalculations the total solar usage is more than 50 %. This house has been made for referenceregarding the design of the heating system of property 5:37.Further studies have been made to compare different heating systems that are compatible with asolar system, where the compared systems purpose is to be independent of direct using electricity. Asystem of this design is regarded as sustainable according to environmental as economic issues.

This master thesis comprises analysis and dimensioning of a keyed joint between a generator axis and a hub with aid from the FEM-software ANSYS Workbench 13.0.The generator axis is a part of a hydroelectric power station that generates electricity with a reactions turbine, a Kaplan turbine. The existing keyway consists of one parallel key with the width 90 mm and height 45 mm. Due to a planned increase of the power of the generated power with 32 % a design study was needed to see if the keyed joint would be suitable for the extra force. Because of the fact that the axis diameter is bigger than the standards covers/recommends a the keyway had to be re-dimensioned. In an earlier assignment from Skellefteå Kraft AB to Sweco Energuide the keyway was planned to be properly dimensioned, but no final solution was approved.During this master thesis a number of different numerical tests were made.

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.

I det här examensarbetet dimensioneras en solcellsanläggning med batteribank till fyra kolonistugor som kommer att vara bebodda under sommarhalvåret på Wij Trädgårdar i Ockelbo. Den förväntade elanvändningen beräknas för två olika brukarbeteenden. Ett brukarbeteende där hushållsapparater med höga effekter (exempelvis mikrovågsugn) förväntas ha kortare drifttider vilket resulterar i lägre krav på installerad solcellseffekt samt en mindre batteribank.För den kemiska energilagringen i en batteribank undersöks flera olika typer av uppladdningsbara batterier. AGM blyackumulatorn är det batteri som anses vara lämpligt för kemisk energilagring i solcellssystemet och som har använts vid dimensioneringen av batteribanken. Vidare undersöks möjligheterna att lagra elektricitet småskaligt genom pumpat vatten till ett vattenmagasin, som ett komplement till energilagringen i batteribanken.

This master thesis comprises analysis and dimensioning of a keyed joint between a generator axis and a hub with aid from the FEM-software ANSYS Workbench 13.0.The generator axis is a part of a hydroelectric power station that generates electricity with a reactions turbine, a Kaplan turbine. The existing keyway consists of one parallel key with the width 90 mm and height 45 mm. Due to a planned increase of the power of the generated power with 32 % a design study was needed to see if the keyed joint would be suitable for the extra force. Because of the fact that the axis diameter is bigger than the standards covers/recommends a the keyway had to be re-dimensioned. In an earlier assignment from Skellefteå Kraft AB to Sweco Energuide the keyway was planned to be properly dimensioned, but no final solution was approved.During this master thesis a number of different numerical tests were made.

This paper aims to explore the phenomenon urban wind energy, its visual effect on built environment and the factors that affect the opinion towards new elements in the city. A place study of the city Gävle serves as a complement to the theoretical part of the paper. The theoretical discussion opens with an account for the technical and economical conditions of urban wind energy. It presents the technical basics, different types of turbines and a discussion occurring wind related techniques in built environment. Today, the knowledge of how the wind moves and acts in the rural landscape is quite good.