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.

The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it?s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C.

Mankind faces a serious threat. Its activities, for example the burning of fossil fuels, have led to an enhancement of the greenhouse effect - something that has given rise to a global warming. The climate is becoming warmer, a change that has important effects on the nature as well as for humans and their society. Sea level rising, extreme temperatures are becoming more common, glaciers and other ice caps melt and storms becomes more intense when they appear. The main cause is the emission of greenhouse gases into the atmosphere - carbon dioxide in particular.

In Swedish sheep industry it is desired to have lambs slaughtered evenly distributed over the year. Swedish sheep are generally seasonal breeders with lambs born in the spring and slaughtered in the autumn. Some of the breeds, e.g. Swedish Finewool and Roslag sheep breeds have shown ability to lamb out of season. For increased knowledge on the possibilities to breed for out-of-season lambing in Swedish sheep breeds, the aim of this master thesis is to study the variation in frequency of two alleles in the MTNR1A gene in the three breeds; Gotland, Swedish Finewool, and Roslag sheep.

AbstractThe Municipality Council decided in 2010 to develop a comprehensive energy efficiency strategy with financial and methodological support from Energimyndigheten (The Swedish Energy Agency). The strategy should include 3 major parts: an inventory of the 2009 energy use defining the current situation, the 2014 and 2020 goals for energy use, and an action plan for goal achievements. According to Energimyndigheten, the strategy must include all municipal administration premises, vehicles, and all majority-owned companies (as Laholmshem, the municipal housing company).The report describes the inventory work in order to obtain the 2009 energy use and the sources of information used. The inventory values are used as the base year values for the 2014 and 2020 goals. The inventory showed that information about the vehicles is dispersed in the municipal administration and no clear structure exists with respect to mileage and fuels used.

AbstractThis bachelor thesis has been assigned by the company ACG Nyström, Borås. ACG Nyström is working in cooperation with a Swiss company named Jentschmann AG. Jentschmann is a manufacturer of ultra sonic welding machines which ACG Nyström is marketing in Scandinavia and the Baltic States. On behalf of Jentschmann AG the company has the aim to introduce the ultra sonic welding technique to new companies.The aim of this thesis is to compare traditional sewing machines with ultra sonic welding machines within two textile areas, protective clothing and outdoor living.Two investigative questions have been formulated for this purpose: what are the differences between a sewing machine and an ultra sonic welding machine? Is it possible to replace the sewing technology with ultra sonic welding? These stand as guidance for this paper.To gather knowledge interviews, literature studies, and tests on two different ultra sonic welding machines were performed.

The work covered in this report includes a literature study of the diesel dual fuel technology(hereinafter referred to as DDF). The literature study covers earlier work that has been doneregarding the use of compressed natural gas (CNG) and diesel in a DDF system. Moreover a onecylinder research diesel engine was fitted with a CNG fuel system for experimental testing. Theinstallation of the engine and the test cell is described. Results from the tests are presentedcovering emissions, heat release and pressure traces from the DDF-concept.During the literature study it was found that most research was related to heavy duty dieselengines.

Constantly growing demands from the costumers in the Automotive industry forces the subcontractors to seek alternative ways to compete. One parameter of quality is the components tolerance against NVH(Noise, Vibraion & Harshness) aspects. Kongsbergs Automotive has developed a new gear shifter platform (Shift-by-Wire) that is sold to Alfa Romeo and used in of their car models. However, the company is not pleased with the components sound quality, therefore the main purpose of this thesis is to develope a number of concepts that is supposed to enhance these NVH-aspects.To get an understanding of the problem an analysis of the causes of the emitted sound has been done parallell to a product decomposition, function decomposition and a Ishikawa-diagram. Together with these methods has a litterature study been performed to get familiar with the physics of an impact and especially the emittment of noise.

Today, about 15 to 20 percent of Sweden?s total emission of carbon dioxide can be traced to the household sector. By examining apartment blocks in a life cycle perspective, the origin of the carbon dioxide emission has been charted and analyzed. This information has been used to create a computational model that calculates the total emission of carbon dioxide from a specific apartment block. The results from the analyzed apartment blocks indicate that both the use of energy and the emission of carbon dioxide have been reduced since the 1960s. Through the examination of building materials, it is possible to lower the emission of carbon dioxide that origins from the construction phase of an apartment block.

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

Städerna växer och samtidigt ökar efterfrågan på närodlade och ekologiska grödor. För att klara av att producera närodlat och mer hållbart skulle ett alternativ vara att odla i så kallade vertikala växthus. I Kiruna finns Sveriges största malmgruva som drivs av företaget LKAB vars olika processer leder till spillvärme. I Kiruna är klimatet kallt jämfört med större delen av Sverige och därför erfordras uppvärmning om odling ska kunna ske året runt i ett växthus. Examensarbetets uppgift är därför att undersöka hur man kan utnyttja spillvärme till ett vertikalt växthus i samband med en ny kontorsbyggnad på LKABs gruvområde.

Today, there are no regulations saying that cows must have access to some kind of shelter at pasture during the summer. In more tropical countries, it is well-known that dairy cows might suffer from heat stress when exposed to sun and high temperatures. The well-being of the cows is thereby reduced and the production may also decrease. In Sweden, no research has been done in the area and therefore it is now a clear need of improved knowledge.The purpose of this study was to investigate the importance of shade for dairy cows in Sweden. The behaviour of 30 cows was examined to see any differences between cows with access to shade and cows without access to shade.

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

Två olika värmesystem i två flerbostadshus har analyserats. Målet med analysen är att få en uppfattning om vilket värmesystem som är mest fördelaktigt i flerbostadshus. I analysen jämförs två olika värmesystem. I värmesystemen används två olika sorters frånluftsvärmepumpar för att återvinna värme ur frånluften. När värmepumparna inte klarar av att producera tillräckligt med värme för att täcka fastighetens värmebehov används fjärrvärme som spetsning.

The task was to design and manufacture a submersible displacement pump working with the wobble plate principle. The main task for the Wobble plate pump is to be used as a sewage pump for smaller households or dewatering pump in environments where small flows and high pressures are acquired. For these purposes ITT Flygt sell a screw pump, PC-Grinder 3068. The hydraulic part of the PC-Grinder is manufactured by a subcontractor. Therefore ITT Flygt wants to evaluate an alternative to their screwpump PC-Grinder, which can be entirely manufactured by them self.