Biogas is a gaseous fuel, rich in methane, produced through a biological route in an anaerobic digester. A gas engine generates combined heat and power, which can be used at the farm to reduce energy cost. The process also generates a digestate, with better utilization of nutrient compared to cattle manure. The aim of this study is to analyze the profitability of a farm-scale biogas plant for combined heat and power (CHP) at Wapnö. Wapnö is an agriculture company located in the southern part of Sweden.

The sun is essential to life on earth and no matter where you are, there is a constant need ofenergy. Nearly 800 000 years ago man learned for the first time to use fire in a controlled way.Since then, fire has given us the opportunity to inhabit places despite a cold climate. In Swedenthe resident sector accounts for a major part of the total consumption of energy. In a time whenenvironmental issues and greenhouse effects are increasing, we also see a future of rising energyprices. With this perspective, we have in this bachelor thesis in the Building Environment at theRoyal Institute of Technology, KTH, in Stockholm decided to focus on the renewable energysource, solar energy.The energy from solar radiation is a free resource and does not have any negative effects uponthe environment.

This diploma work on D-level is made in cooperation with Varnäsföretagen AB in Eskilstuna. The company performs contract manufactured aluminium goods. This work is a continuation on earlier diploma work in Varnäsföretagen AB. Even if the industry process consumes much energy for melting the aluminium goods, they consume a great amount of oil to warm up the building. The purpose of this work is to examine some places in the building and the process to see how much energy it is possible to recycles to the heating system and reduce the costs for heating.

The examination has been performed at Bjerking AB, which is an architectural and engineering company. Bjerking AB has the ambition to be a member of Green Building.The Green Building program developed in year 2005 by The European Commission, the program is an environmental system with the aim to improving energy efficiency within the sectors of non-residential buildings. The minimum requirements to participate the program are following: in new-built buildings the calculated energy consumption must be 25 % lower than the requirements in the BBR (Building regulations) and in refurbishment the reduction must be 25 % lower than before the optimization.The aim of this study has been to examine and review the company Bjerking AB's energy efficiency work in the project of building the school/kindergarten S:ta Maria Alsike, where the goal is to get this building Green Building classed. A description of requirements to become a member of the Green Building has also accomplished in the thesis.The methods performed in this study are literature review, searches on the Internet, studies on the project database for facts/values, calculation of energy consumption and interviews of members of the Green Building. The following issues have been dealt with in the report;-          Did the building in the project manage the requirement to achieve an   energy consumption that is 25% lower than the requirements in BBR?-          What technical measures/system was selected in the building?-          What kind of cooperation was the project based on?-          What is required for consultancy companies and real estate owners to become members of the Green Building?The study of the project and calculation of estimated energy consumption in the building, give the result 47 kWh/m2, year.

The society strives for sustainable development, in the construction industry it is expressed through sustainable building. Energy and LCC analyzes increases the ability to make conscious decisions in the process. A problem in the construction industry is that energy and LCC analysis is not used to the desired extent, as they are perceived as complicated and time consuming. The report aims to achieve a more sustainable building through increased use of energy and LCC analyzes.The goal is to show how BIM can be used to improve the efficiency of the energy and LCC analyzes.The study was conducted with a literature review and a case study to answer which information that is required in a BIM model to perform energy and LCC analyzes. The study also shows which software can be used in BIM based energy and LCC analyzes and how the analyzes can be carried out efficiently.The result shows that effective analyzes may be performed if the BIM-model contains the relevant information for making analyzes.

sustainable development by reducing the energy use by EU:s directive of energy efficiency and the UN Convention. The second purpose is to present the technical solutions regarding ventilation and heating system that is being used in passive houses. This was done using 8 passive houses, 4 germany and 4 swedish passive houses. Even the international and Swedish system requirements for passive houses have been addressed in this project. The goal was also to explain how and why the mechanical system in passive houses has developed to the technology used today.

Energy is today a very common topic, not only in Sweden but in the whole Europe. In EU they have given out a directive 2002/91/EG about buildings energy use and throw this they have forced their members to show how much energy their buildings use. In Sweden has the gouvernment established a law (SFS 2006:985) about energy declaration for buildings which demands that the building owner needs to show how much their buildings energy consumption are. Important to know is that this law doesn´t applies for industrial buildings.The report will show what the new law about energy declaration for buildings and appurtenant directions will mean for Riksbyggen. Also energy calculations will be done to be able to compare Riksbyggen buildings with the new law and directions.

This bachelor essay is divided into two parts, the first being a construction of a single-familyhouse and the second an in-depth study of five different isolation materials, analysed from anenergy perspective.The first part, the construction of the single-family house, has been created from knowledgeacquired during three years of studying at KTH Royal institute of Technology in Stockholm, inthe program Architecture and the Built Environment. The constructed house is a one-floorhouse of 137m2with façade plaster, situated in Borlänge, Sweden. The house has a wooden framewhich is built on a on sight cast concrete foundation, on the ground. The house?s roof is a gableroof, which has an angle of 24 degrees.

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.

Compressed air is a low efficiency media, and is thus very expensive to produce. This thesis work began by mind mapping how to create savings on the compressed air system at Billerud Skärblacka AB. Certain issues have been chosen for further studies.In order to identify the consumption of compressed air at PM 8 and 9, several measurements were made. At PM 8 there were not found any pressure drop, only large pressure variations for short periods of time. The causes of these pressure variations were not established.

The number of data centers and their capacity is increasing throughout the world. Theenergy used in these data centers and the emissions from the use are increasing at thesame rate. The total use of energy will double from 2008 to 2011 based on the trends indata centers use. Research in this area says that the emissions from data centers willhave surpassed the level of airline traffic in 2020. The index used today to compare howefficient a data center is, called PUE, is lacking some information.

The society strives for sustainable development, in the construction industry it is expressed through sustainable building. Energy and LCC analyzes increases the ability to make conscious decisions in the process. A problem in the construction industry is that energy and LCC analysis is not used to the desired extent, as they are perceived as complicated and time consuming. The report aims to achieve a more sustainable building through increased use of energy and LCC analyzes.The goal is to show how BIM can be used to improve the efficiency of the energy and LCC analyzes.The study was conducted with a literature review and a case study to answer which information that is required in a BIM model to perform energy and LCC analyzes. The study also shows which software can be used in BIM based energy and LCC analyzes and how the analyzes can be carried out efficiently.The result shows that effective analyzes may be performed if the BIM-model contains the relevant information for making analyzes.

Former studies have shown that a considerable part of industries? energy usage can stem from idle times in the production. This thesis, carried out at Siemens Industry sector, evaluates the potential for using the control system to automatically put machines into energy saving mode during idle times. The main part of the thesis consists of a case study performed on machine tools at a Scania production site in Södertälje. Through load measurements the potential for energy savings was determined.The results show that there is a great potential for energy savings during idle times at the site.

This thesis has identified and studied measures to allow for reduced use of electricity in a waste incineration plant in western Sweden. The energy extracted from the waste at the powerplant is utilized and sold in form of electricity and heat. Technical and environmentally the combined heat and power plant is by today's standards among the leading waste incineration plants in the world. The owners are constantly striving to improve the efficiency of the waste incineration plant. They have seen the opportunities for savings in reducing internal usage of electricity.

District heating covers around 80 % of the heating demand in apartment buildings and 10 % in single-family homes in Sweden. In the year 2010 the total input of energy to the Swedish district heating grids was about 70 TWh, which corresponds to 11 % of the total energy input to the whole energy system in the country. Through the combined production of heat and power the CHP-plants often reaches an efficiency of 90 % from energy in the fuel to produced heat and power. In order to keep the efficiency high it is important for the owners of the plant to have good knowledge about the plants performance at different operation points. Strängnäs Energi AB initiated this diploma work together with FVB Sverige ab in order to come up with a program for short term planning of the production of heat and power at the company´s CHP-plant.The work consists of three main parts.