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.

In this project a simulator has been developed (in C++) with the purpose of illustrating how changes in environmental regulations, tax levels and other policy measures affect the composition of an energy system. The aim of the project was to investigate how energy companies? investment strategies are affected when changes in economic and environmental conditions occur. A standard scenario has been created based on current Swedish conditions, but the user can create new scenarios and set parameters freely. The user is tasked with building power plants to supply the city/region with district heating and electricity during a pre-set number of years. When the simulation is finished the result is graded in the following categories: economy, environment and quality. To evaluate the simulator three scenarios were created (?early 20th century?, ?reduced environmental control? and ?future?) in addition to the standard scenario and these were compared with each other by examining how a select group of power plants perform under the given conditions.

Nematode-transmitted plant viruses (such as nepoviruses) cause great economically losses in commercially important plants such as tomatoes, grapevines and raspberries all over the world. To avoid spread of the viruses the interest in mapping the viruses has increased. One of the important nepoviruses infecting European red raspberries (Rubus idaeus) is Tomato black ring virus (TBRV). TBRV has earlier been confirmed in raspberry samples from Belarus by ELISA and the aim of this bachelor degree project was to confirm these results by amplifying, cloning and sequencing the coat protein (CP) gene of the virus. In total eight viral cDNA samples, from two different raspberry samples, were amplified and sequenced.

In this report a systematic working procedure for risk classification of processing equipment from a maintenance point of view is described. How this system has been worked out is also an important part of the report. The classification system is adapted for use in complex processing plants. Preemraff Göteborg has been subject for the underlying study and application of the system.The system aims to give a good overview of the maintenance related risks at the plant. Furthermore, the analysis result is a good motivation for the suggested maintenance activities and as motivation for extended or decreased maintenance resources in total.

The aim of our research was to investigate if oat is capable of extracting cadmium to such extent that it is usable in decontaminating polluted soils. We grew oat in a hydroponic culture during 28 days in a controlled environment and a total of 30 plants were used. The nutrient solutions were contaminated with cadmium of ten different concentrations after seven days. After harvesting the plants, the roots were separated from the shoots, placed in separate containers and then turned to ashes. The cadmium content was measured three times per sample in an atomic absorption spectrometer.Our results indicate that the ability of oat to extract cadmium from a solution is linearly dependent of the cadmium concentration of the solution.

In Sweden there are 1894 small-scale hydropower plants in operation, which together generate 4.3 TWh of electricity per year according to Swedish hydropower compound (SVKF, 2011). This corresponds to the annual consumption of about 860,000 Swedish households (based on an annual consumption of 5000 kWh). In the mid-1950s there were around 4000 small-scale hydropower plants in operation in Sweden before cheap fossil fuels and uranium competed with them, in the current situation only 1,894 of these are in use. If slumbering small hydropower plants once again would be taken into use and some new ones are built, we would be able to extract about 7 TWh of renewable electricity from these annually in Sweden, representing about 1.4 million households.The thesis intends to calculate and construct a hydroelectric power plant at the existing dam in Olofsfors and give suggestions on how the power station should run during the time that fish migration is greatest in Leduån.The turbine and generator to the station in Leduån at Olofsfors is designed by the height of the fall and the water flow through the dam. The turbine selected for the station is a CK-1000RM turbine with a 4-pole 250 kW generator from Cargo & power turbine Sweden AB, which is expected to deliver 1.2 GWh per year.

One of the most common ways to produce heat and electricity in Europe today is by the incineration of waste or combustion of coal. These materials can be very sulfurous and during combustion sulfur dioxide is produced. This is an environmental and health related toxic substance which is why power plants have strict regulations on removing it from the flue gas. Sulfur dioxide is removed from the flue gas by adding a limestone reagent. The sulfur dioxide reacts with the limestone and the synthetic product obtained is ?Flue Gas Desulfurization gypsum?.

In order to facilitate design and maintenance of such a large and complex site as a nuclear power plant, all system functions must be described in a stringent way. In the past, these descriptions consisted of text documents and logical diagrams, but today there are an increasing number of object-oriented programs available on the market which might be used for this purpose. This Master Thesis has made a closer study of one of these programs named Rational Rose. The principal of the program is to facilitate software design and development, not to create models of plants. However, using the program the same way as developing software, specifying actors then gradually extend the model with use cases, use cases diagrams etc, the same methods can be used when modelling plants.

This thesis analyzes the expected profitability in land based wind power plants. The expected profitability is calculated on the basis of a wind power project in Vartofta, Falköping. The information required to calculate the expected outcome is then concentrated to this project, which is in this thesis called project Näs. In project Näs they plan to build three wind power plants, with each an effect of 2 MWh. These wind power plants are very capital intensive investments with a long and uncertain payback time.

Sammanfattning Kisel (Si) är det näst vanligaste ämnet (drygt 25 %) i berggrunden. Bara en del av detta är tillgängligt som monokiselsyra, den form i vilken kisel är upptagbart för växter. Jordens kiselinnehåll är beroende av bergets vittring. Mycket höga halter av kisel återfinns i naturen i vulkaniska substrat (pimpsten innehåller drygt 66 % Si och scoria närmare 47 % Si), i diatomit (ett mineral bestående av resterna från encelliga kiselhaltiga alger, s.k. diatoméer) innehållande 66 % Si, scoria approximatly 47% Si), in diatomite (a mineral consisting of the remainings of single celled algae, diatoms containing < 40 % Si) and in some clays (30-60% Si).

Tomato production is a common and important agricultural activity in Nicaragua. During the last decades tomato producers have suffered great yield losses due to begomoviruses (family Geminiviridae). The genome of begomoviruses generally consists of two circular ssDNA components, DNA-A and DNA-B. Tomato yellow leaf curl virus (TYLCV) is an example of a begomovirus with only one component. An approach to manage the virus epidemics has been to breed a cultivar with begomovirus resistance genes, which have been transferred from wild tomato.

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

The aim of this thesis is to develop a new business model for district heating and cooling firms which can contribute to a stabilization of the Swedish national energy system. The business model is developed for a district heating and cooling firm and is exemplified with Fortum Heat. The theoretical investigation around the topic creates a rigid base for following qualitative empirical studies. Osterwalder?s canvas for business model generation is used together with a Casual Loop Diagram to identify a number of business opportunities which stabilizes the national energy system.

Sigill Quality Systems has been certifying beef since the autumn of 2006 using the brand name label Swedish Sigill. IP Sigill (the certifying system for integrated production) encompasses the values: animal ethics, food safety, free range and environmental concerns. Product quality is not yet one of these values, and there is a variation in the quality of Swedish beef. Swedish Sigill wanted to investigate the factors that influence product quality, review which of the present regulations that have an influence on product quality and formulate new regulations with the purpose of enhancing the product quality (sensorial, technological and nutritional quality). A survey of quality parameters and factors that influence product quality was done in order to establish a scientific foundation to work from.