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3861 Uppsatser om Energy power - Sida 49 av 258
Pellets - en framtidsmarknad?
With higher prices for oil and increased focus on fossil fuels impact on the environment the heating sector are searching for alternative fuels. Pellets are a quite new product whose production has risen exponential in recent years. Today there are small-, medium-and large-scale users, where the large-scale consumers are the heating sector. The heating sector is mainly using oil to cover the increased demand during cold periods.
The purpose of this study is to analyze the potential of pellets if it would replace thermal power plants oil and coal. The study will also analyze the economic impact a conversion would mean for a heating plant and if the pellet is a reasonable substitute.
2008 statistics from the Swedish district heating association were analyzed and a calculation was performed to determine how many tons of pellets is needed to replace coal and oil.
Tilla?mpning och simulering av naturlig ventilation : Potential fo?r utnyttjande i kontorsrum
Mechanical ventilation is the most common type ofventilation in newly constructed office buildings. Therehas been an interest to utilize natural ventilationinstead of mechanical ventilation among architects andHVAC consultants in recent years. This is due to thesize of mechanical ventilation systems, which arespace consuming. The mechanical ventilation system isalso complex and requires maintenance. Furthermore,the fan uses a considerable amount of energy.
Småskalig biobränsleeldad kraftvärmeproduktion : teknik och investeringsutrymme
To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.
Flygteknik : Konceptstudie av ett obemannat flygplan
Unmanned aerial vehicles (UAV?s) are nowadays greatly appreciated. The advantage over manned airplanes are great since UAV?s can be much smaller and therefore lighter. The goal of this project is to evaluate the performance of an environmentally friendly UAV using only lithium-ion batteries.
Biobränsle från det jämtländska jordbruket : en studie om lantbrukarnas alternativkostnader vid odling av rörflen
The use of fossil fuels such as coal and gas are a contributor to the global warming. The climate change is a worldwide problem with far reaching consequences that is believed to be very expensive. The United Nations has been introducing a framework convention on climate change. One component of the convention is the Kyoto protocol. The protocol is obligating the developed countries to decrease their emissions of greenhouse gases by 5.2 percent during the time period 2008-2012.
Bergkyla och bergvärmeutredning för industrilokalen Rödbergsmyran 5 i Umeå, Västerbotten.
Grubbe Ventilation AB is a sheet metal and ventilation company who provides design, installation, service, and repair of ventilation. The company is expanding their business by building a new facility in Umeå, Västerbotten. The property is designed to be used for both office and industrial work.Grubbe Ventelation AB has not yet decided upon wish system which is to be established to provide the building with heating and cooling. The consulting firm Umeå Projekt Team has therefore been asked to investigate the possibilities to invest in geothermal- heating and cooling.If the investigation of a geothermal heating- and cooling system would provide favorable results it would be a very appropriate alternative that provides energy at low costs and are an environmentally friendly option as the energy comes from stored solar energy in the ground is provided by stored solar energy in the ground.The facility ´s heating and cooling consumptions are calculated in the program BV2 and the result indicate a heating demand of 185 000 kWh per year due to thermal transmittance, transmission losses, heating of warm water and a cooling requirement of 5500 kWh.Three different systems of geothermal heating and cooling were tested in the computer program Energy Earth Design. The results show no difference in the dimensioning of the drill hole if merely heating were to be used or both heating and cooling were to be established.
Konceptstudie av kombinerad nödgenerator-trädgårdsredskap : Concept Study of a Combined Emergency Generator-Garden tool
The present study concerns a concept development of a product idea that Bengt Magnuson, associate professor, had when a heavy storm caused a widespread power failure of long duration. With a basic power-producing unit one should be able to get through a power loss. The product could also be useful for other tasks if different modules are connected, e g grass mower or snow-blower.According to the product idea the basic unit will be able to produce electric power enough for a fridge, freezer, TV, and a few electric lamps. Normally the basic unit can be used e g as a mower, when such a module is attached. An increased number of tasks would make the contraption useful and tempting for those who do not own an electrical power set in reserve.
Temperaturzoner för lagring av värmeenergi i cirkulärt borrhålsfält
The thermal response of a borehole field is often described by non?dimensional response factors called gfunctions.The g?function was firstly generated as a numerical solution based on SBM (Superposition BoreholeModel). An analytical approach, the FLS (Finite Line Source), is also accepted for generating the g?function. In thiswork the potential to numerically produce g?functions is studied for circular borehole fields using the commercialsoftware COMSOL.
Optimerade material för optiska komponenter i koncentrerande solfångare
The energy consumption continues to increase as the use of electronics and energy consuming equipment increases. The use of fossil fuels has to be phased out for this to be sustainable in the long run while the use of renewable energy continues to increase. A renewable energy source is solar energy but the production of heat and electricity are today very expensive compared to other energy sources and an important task for the solar energy market to grow is therefore to minimize the production cost of the solar collectors while increasing its efficiency to produce heat and/or electricity. One way to convert solar energy into heat is by using solar collectors and electricity can be produced by utilizing the produced heat, or by applying solar cells.This thesis aims to recommend a reflective material for the next generation solar collectors from Absolicon and to recommend a commercially available coating for the receiver tube of the solar collector. A market study has been carried out to investigate the cost-related aspects along with the optical and durable aspects for the optical material of the solar collector.
Effektiviseringspotential inom industrisektorn : Energibesparing vid frekvensstyrning av centrifugalpumpar ? en fallstudie
The project was performed at SiemensIndustry Drive Technologies with theobjective to provide actual values forthe energy savings potential withinSiemens scope of practice.In Sweden the electrical drives standfor about 30 % of the total electricityconsumption and about 60 % of theelectricity consumption within theindustry. During the pre-study phaseelectrical drives with pump applicationswere identified as large energy users.Because of this a case study at one ofSiemens customers, Stora Enso Fors wasperformed. The system that was evaluatedduring the case study was a throttledsystem with a centrifugal pump forpumping pulp.The results yielded that a saving ofover 50 % could be achieved by replacingthe throttle valve with a variable speeddrive, a frequency converter. Thepayback period was two years and twomonths and the present value for thetotal life cycle cost of the variablespeed system was 662.566 SEK lower thanfor the throttled system. As aconsequence, Stora Enso Fors is advisedto invest in a frequency converter forregulation of the system.The general conclusion is that a focuson system efficiency is the mostimportant factor in energy efficiencyprojects and that the system regulationmethod has a large impact on the overallsystem losses and hence its efficiency.Energy efficiency potential forthrottled systems with centrifugal pumpsis large and significant economicalsavings can be made through investmentswith short payback time..
Värdet av att bygga grönt för kommunala bostadsbolag
AbstractThe real estate sector is today responsible for 40 per cent of the total amount of energy consumption within the members of the EU. All over the world there are collaborations within research and projects to find ways of reducing the amount of energy consumed by the real estate sector. In Sweden, a directive from the European Union has posed demands on authorities as well as on the private sector to reduce the amount of energy consumed by new building constructions. Together with the directive from the EU there are also new requirements and demands from Boverket for the real estate sector. These requirements mostly concern the energy consumption of kilowatt-hour per square metre and that the consumed energy also should be renewable. The aim of this study is to explain what kind of value municipalities experience in using certifications and environmental investments for new and existing buildings. Within the chapter theory, essential areas are described such as; environmental certification systems, economical viability, proceeds connected to building green, difficulties with building green, the performance of green buildings when affected by the behaviour of tenants and customer value. The following chapter describes the methodology with which we have conducted this study.
Gradering av vindkraftslägen i Lerums kommun med hänsyn till infrastruktur och läge
The aim of this master thesis was to find and grade suitable sites for wind turbines in the rural district of Lerum at the reguest of Göteborg Energi. The rural district of Lerum consists of very complicated terrain which was the reason why we picked Lerum.The assignment was achieved by using the software program ArcGIS and its attendant tools. In step 1 an overall analysis was made in order to sort out the least suitable sites. Step 2 consisted of a 3D analysis in ArcScene together with a more precise analysis in ArcMap. As result we found two interesting sites, which met our demands and specific constraints.
Skådespelerskor i politiken : En innehållsanalys om mediers gestaltningar av kvinnliga och manliga politiker
As a starting point the society is more enlightened and has gained a greater awareness about the gender power structures and its different forms. Present research shows the continuous development into other shapes and comes into different expressions that might be unrecognised. In order to gain knowledge about the present structure of the gender power structure system, the aim of this study was to investigate framing of female and male politicians in media. The main question asked was: ?are there framing differences in the portraits of the male and female politicians?? In order to achieve results articles in the biggest Swedish daily newspaper were examined.
Bemötandet inom socialtjänsten : En kvalitativ studie om klienters upplevelser
The aim of this study was to examine how clients who have or have previously had a drug- and/or alcohol addiction experienced interchanges with social workers. In this study, eight semi-structured interviews were made with respondents from an out-patient clinic in a small town in Sweden. Questions were asked regarding clients? experience of the social workers' attitudes during the initial meeting as well as all continuing meetings. Other possible variables that affected the interchanges, either positively or negatively, including how the clients wanted to be treated, were also explored.
Bioenergy from the forest ? a source of conflict between forestry and nature conservation? : an analysis of key actor?s positions in Sweden
Bioenergy from the forest has been heavily debated in Sweden for several decades due to the interest of society to decrease dependence upon fossil fuels and limit the effects of climate change. The actual use of bioenergy from the forest has shifted over the years but increased during the last decades. Private actors within forest and nature conservation sectors play an important role for the development of bioenergy from the forest as well as for the debate and the implementation of political goals. Forestry in Sweden is characterised by ?freedom under responsibility? for private actors and the perspective of governance is valuable for studying actors and discourses.