The aim of this study is two folded. We wish to investigate if there is a value premium from hedging jet fuel exposure for American and European airlines. We also seek to answer if airlines can affect their probability to default by using Risk Management. During the period 2003 ? 2006 there existed a value premium for airlines that hedged their expected future consumption of jet fuel.

Global warming is a huge issue that humans have contributed to through over-exploitation of natural resources and extensive usage of fossil fuels. Now more than ever, we need to embrace a recycle thinking and reuse our waste, for example through producing biogas from our food waste. The purpose of this report was therefore to identify the energy usage and emissions resulting from the biogas chain which spans from Solna Stad to Uppsala Vatten. Furthermore, potential efficiency improvements were to be identified and proposed. This report focused mainly on the first part of the biogas chain that includes the collection of the food waste and the reloading process.

Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer (system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.

The purpose of this study is to compare the economic differences between withdraw of forest fuel and withdraw of pulpwood in first thinning, to see which method gives the maximum profitability (income - cost). Another purpose is to investigate the economic impact of the thicket cleaning. The study compares four different methods: i) pulpwood output with thicket cleaning, ii) pulpwood output without thicket cleaning, iii) forest fuel output with thicket cleaning and iv) forest fuel output without thicket cleaning. The study was conducted in a 30-years old stand, dominated by spruce, outside Harg in Uppland. The method that generated the best economic net income was pulpwood without thicket cleaning. It generated a positive net of 1,383 SEK per hectare. Forest fuel output without thicket cleaning also generated a positive net in 720 kronor per hectare.

Vehicle simulators are becoming more common in vehicle industries. Company earns lot of money on simulations instead of real tests. Real tests are necessary but not made so extensively as before.In this thesis the building of an vehice simulator will be described and a comparison between three different cruise controls. The three cruise controls are PI-regulator, a regulator who regulates after positions in the terrain and a MPC-regulator. The reason for choosing this three is to see the difference between simple regulation and more complex regulation with respect to fuel consumption, travel time and complexity.The vehicle simulator is made in Matlab/Simulink, Visual Studio and Open Scene Graph.

A Monte Carlo simulation of the ELECTRA reactor using (U,Zr)N fuel and a liquid lithium coolant is performed using the Serpent simulation code. The results show a reactor with a total reactivity coefficient of the coolant, fuel and material expansion that is strongly negative. These properties make the ELECTRA reactor a good candidate for a safe space reactor that could be used for propulsion of manned and unmanned space vehicles to Mars and other parts of our solar system..

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

This report was written by Sofia Ericson and describes the degree thesis with the title: ?Connections between the growing site of bio fuel, the chemical composition of bio fuel ash and the deposit growth in a bio fuel fired boiler.? The purpose of this degree thesis was to avoid melted deposit growth in the bio fuel fired boiler at ENA Kraft in Enköping. Potassium and sodium are known to lower the melting point of bio fuel ashes and are therefore not wanted in the trees in higher amounts than necessary for the growth. Silicon is also known to be important for the deposit growth but it is not possible to say in general if higher or lower contents of silicon is better. The relation between silicon and other chemical substances is more important than the total amount of silicon.

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.

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

At SIA TallOil's pellets factory in Latvia wood shavings and saw dust are dried with flue gases from a gas burner. TallOil wants to replace the gas with a biofuel that is available at the pellet plant. The reason for this is the unstable gas market in Europe in combination with the fact that TallOil wants to improve its profile as supplier of renewable bio fuels. In this project the technical and economical possibilities for a fuel conversion to ether bark powder, wood shavings or wood powder have been investigated. These fuels should be burned in one of the following applications: TPS BioSwirl, VTS Multifuel burner or Saxlunds bio fuel combustion plant Due to the fact that the fuel alternatives available are relatively common except for bark powder, the work has mainly been focused on bark powder.

A third party access to district heating networks has been proposed in Sweden, to increase the competition on the district heating market. Such third party access could create opportunities for the agricultural sector as an energy producer. This study describes the technical, economical and environmental prerequisites for a farmer cluster to build and run a heating plant, fueled with local wood fuel. The heating plant in the described scenario is 8 MW and will supply a village of 1000 houses, and is fueled with wood chips exclusively. Supplying a heating plant with fuel puts high demands on the logistics, since there need to be a continuous flow of fuel. In the scenario, wood residues from felling and thinning is stored in stacks in the forest, and a few times a year chipped and transported to a storage area at the heating plant. In the study, an estimation of the profitability has been made by estimating the cost of the investment, personnel, operating and maintenance costs and costs for the fuel and ash handling.

This thesis describes an optimising compiler for translating from SMV to CLP(B). The optimisation is aimed at reducing the number of required variables in order to decrease the size of the resulting BDDs. Also a partitioning of the transition relation is performed. The compiler uses an internal representation of a FSM that is built up from the SMV description. A number of rewrite steps are performed on the problem description such as encoding to a Boolean domain and performing the optimisations.

Stump biomass is energy rich and stump harvesting for use as fuel become more and more interesting in Sweden. Swedish Forest Agency (2009) has estimated that stump harvesting in Sweden would respond to an annual energy supply of 57 TWh/year. However, stump has not been recognized as a bioenergy resource in Sweden. Suitable methods for pre-treatment of stump are probably of great importance to make it accepted as fuel. It is therefore rewarding to carry out an investigation in this area for stump. This report represents results from a diploma project, which was aimed to develop a fixed bed reactor for experimental study of biomass torrefaction, followed by TG analysis and kinetic modelling employing Ozawa method and different kinetic models including one-step and three-pseudo-component models.

This project examined the possibility to create an electronical aid with the purpose of increasing environmental awareness and to design the aid in a fashion that inspires other to develop similar applications. The impact of car traffic was examined, and the base of the aid was built up in modular form to simplify the hardware aspect. For the active, data processing part of the aid the Arduino platform was chosen because of its simplicity and big possibilities of help in different internet fora, for those who choose to create similar applications in the future. The main part of the project var the use of real-time information from the car?s on board diagnostics.