The product structure of the fuel tank installation is one of the most complex product areas at Scania. Caused by the number of parameters, which affect the fuel tank installation, a product structure is created which is very difficult to handle. Knowledge exist that the structure in a nearby future will be considerable more complex. The purpose of the study has been to understand in why this complexity exist and find ways to break the trend of a growing product structure. The goal was to achieve a more standardized fuel tank installation.A theoretical study was performed in order to bring knowledge in relevant areas both in general theory but also in documentation at Scania.

Research on Stone Age hunters and gatherers in Norrland has been lively since the 1960s. Central to this research are questions about the organization of society, sedentariness, continuity and resource management. One central part of life in the taiga is the need for fire and fuel. This aspect has been little discussed in conjunction with the mentioned research questions. My goal is to show that the matter of fire and fuel is an important one that needs to be taken in to consideration when discussing Stone Age Norrland and hunter/gatherers.

 With the increases in fuel costs due to the depletion of the world oil reserves and the increase of greenhouse gasses as a consequence to using oil as a fuel many companies are looking to new and innovative ways to power their aircraft. One of these new ways to power an aircraft is using fuel cells powered using hydrogen and oxygen, thus producing nothing but water vapour and small amounts of nitrogen dioxide as well as trace amounts of other emissions. Both Boeing (1) and Politecnico di Torino (2) have shown that it is possible to build an all-electric aircraft powered by fuel cells. Both flights used small, two-seater aircraft and a constant between them was the loss of the co-pilot seat due to weight and lack of space. As this paper will deal with a commercial aircraft a primary concern is the cargo and passenger capacity and whatever impact switching propulsion system has on these.

Dimensional stability is an important aspect of fuel mechanical design and licensing of new fuel designs for nuclear power plants. Dimensional changes within the reactor can affect the safety margins against overheating of the cladding and the pellets, therefore it is crucial that the dimensional changes are kept to a minimum.The profits per produced kiloWatt hour continue to decrease for the Swedish nuclear power plants. Some reactors are even operated with a calculated loss. To reduce fuel costs and thereby improve the profit some reactors are operated with higher uranium enrichment, so that the assemblies can reach a higher average burnup. This increases the neutron fluence to the pellets, cladding an spacers.

The use of bio fuel is increasing every year. Nowadays you will find different alternatives to oil and electricity heating system. In this essay I have examined what the economic conditions are to invest in a bio fuel furnace. I have chosen to assume from a specific farm and do a case study on this farm. Malmvik farm is located just outside of Stockholm.

As the Swedish governments long term goals include a reduction of fossil fuel dependency, increasing pressure is placed upon energy companies to create and develop new solutions for renewable energy. The following case study was done in collaboration with the company Sydved Energileveranser AB and one of their contractors, Enarssons Skogsentreprenad AB. The objective of the study is to examine the bioenergy situation in region of Skåne and evaluate the potential solutions in the region for a forest-fuel assortment, based on a bioenergy-cutting-system. As a part of this study I have compared ordinary manual cuttings done with a chain saw and cuttings made using the new ?bio- energy cutting system?. The cuttings made under both systems were tested in areas near agricultural fields or pasture land in order to maintain an open landscape.

The demand for biogas as vehicle fuel has risen sharply and there is a great need for increased production. A possible addition of vehicle gas can be produced by upgrading landfill gas which is formed by degradation of organic waste. This thesis investigates the potential of producing vehicle fuel from landfill gas in the region of Biogas Öst.In 2008, an amount of 32 million Nm3 landfill gas was extracted in the region. This level can be maintained for another ten years if the efficiency of gas extraction is improved. The annual production will decrease with time since landfills aren?t allowed to receive more organic waste.

New energy resources that can replace petroleum diesel are needed and biodiesel may be an excellent substitute. During storage and use, biodiesel can oxidize and form peroxides, leading to degradation of the fuel. It is therefore important to determine the peroxide content of the fuel. In this thesis the triphenylphosphine method, which involves GC-MS analysis has been compared to the standard iodometric method which involves titration with sodium thiosulfate. Working standards were made to see how well the iodometric method worked and also in order to make a calibration curve in GC-MS.

This study has analyzed particel size distribution and needle content in chipped logging residuals (branches and tops) delivered to the district heating plant Ryaverket in city of Borås, Sweden. Two fuel assortments has been analyzed: Chipped logging residuals from pure softwood and from mixed fuel (connifers and broadleaves). The samples has been sieved at Linneaus University laboratory.The study of particle sizes indicates that only 53,2 % of delivered fuel is within the fuels specification (7? 45 mm). The needle content is in this study 12,4 % (dry mass) which is higher than expected..

Mathematical models possible to simulate are of great importance in order to make successful projects in the aircraft manufacturing industry. An aircraft fuel system is very complex, containing pipes, tanks, orifices, valves and pumps. The principal of this thesis is using the tool Easy5, which no longer is considered reliable enough in terms of development and support. This thesis tries to evaluate the Modelica language as a possible alternative to Easy5. To make this evaluation, the components concerned in the fuel library in Easy5 are implemented to the Modelica language.

There are several energy systems in the Swedish society and to ensure the comfort and health of the citizens it is of importance that the different energy systems are functioning properly. District heating is one of these energy systems and many household depend only on district heating to warm up their homes. District heating is dependent on several processes where every step needs to function in order to deliver the produced heat to the end consumer. Previous studies have investigated the distribution of district heating and how to make customers choose district heating as their heating method. The supply of fuel to the district heating plant has not been studied as much, even though it is an important part of the whole system. This thesis is a part of the project NORD-STAR (Nordic Strategic Adaption Research), which has focused on climate adaption in the Nordic countries.

The gas turbines in the Swedish secondary reserve are reaching the end of their technical lifetime, hence alternative solutions need to be considered. One of the solutions thought to have the greatest potential is the use of so called consumptionreduction. By entering contracts with large consumers, agreements are made to reduce consumption in the event of major disturbances in the power system and thus being used as a secondary reserve. This thesis investigates the feasibility of consumption reduction as part of the secondary reserve. This has been achieved by developing a requirement specification for the disturbance reserve and by studying the technical and economic potential for consumption reduction among a range of consumers.The technical potential for consumption reduction that fulfils the requirements for participating in the secondary reserve are on average 750 MW in SE 3 and 98 MW in SE 4.

The purpose of this study is to investigate university students, studying social work, attitudes against the drug policies, zero tolerance and harm reduction. This was done by quantitative survey utilizing questioners targeting students in semester one to four at Stockholm University, Department of Social Work. The study included 295 students responding to the questioners. The results have been analyzed utilizing theories regarding attitudes and their influence of different social aspects; social influences, social norms and conformity. The result of this study shows that the students prefer the drug policy of harm reduction over zero tolerance.

The gas turbines in the Swedish secondary reserve are reaching the end of their technical lifetime, hence alternative solutions need to be considered. One of the solutions thought to have the greatest potential is the use of so called consumptionreduction. By entering contracts with large consumers, agreements are made to reduce consumption in the event of major disturbances in the power system and thus being used as a secondary reserve. This thesis investigates the feasibility of consumption reduction as part of the secondary reserve. This has been achieved by developing a requirement specification for the disturbance reserve and by studying the technical and economic potential for consumption reduction among a range of consumers.The technical potential for consumption reduction that fulfils the requirements for participating in the secondary reserve are on average 750 MW in SE 3 and 98 MW in SE 4.

The gas turbines in the Swedish secondary reserve are reaching the end of their technical lifetime, hence alternative solutions need to be considered. One of the solutions thought to have the greatest potential is the use of so called consumptionreduction. By entering contracts with large consumers, agreements are made to reduce consumption in the event of major disturbances in the power system and thus being used as a secondary reserve. This thesis investigates the feasibility of consumption reduction as part of the secondary reserve. This has been achieved by developing a requirement specification for the disturbance reserve and by studying the technical and economic potential for consumption reduction among a range of consumers.The technical potential for consumption reduction that fulfils the requirements for participating in the secondary reserve are on average 750 MW in SE 3 and 98 MW in SE 4.