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9400 Uppsatser om Energy research - Sida 29 av 627

Vindkraftsplanering i skogsmark

The aim of this study about wind power planning in forest was to examine the factors and restrictions, which represent technical limitations, biodiversity, tourism and amount of energy for wind farms in Kronoberg County. Suitable areas for wind power were identified from the collected information about planning principles and potential conflicts. From the suitable areas the potential energy gain is calculated. Methods used were mainly a literature review, interviews with experts and practitioners, GIS analysis and a rough calculation of the energy gain. The section of information and facts describes in general wind power planning and possible conflicts.

Biogasprocessen : Bestämning av verkningsgrad

Biogas is increasingly used for fuel in for example vehicles and it´s produced in a biogas processconsisting of the steps of pretreatment, digestion and gas cleaning. The pretreatment is a method usedto increase the gas production and / or destroy pathogens. The digestion is the stage when anaerobicmicroorganisms convert bio-mass of a substrate to a raw gas containing about 65% of methane. Thegas cleaning is used to increase the methane content to about 97% so the gas can be used for motors invehicles. The biogas part of the Ekeby sewage plant in Eskilstuna is using multiple substrates.

Grovkrossning av stubbar : en produktivitetsstudie

The Swedish parliament has decided that Sweden should increase its usage of renewable fuel sources to a level of 50% of the total energy consumption in Sweden by the year 2020. One way to reach that goal may be to increase the usage of stumps as a bio-fuel. In Sweden stump harvesting is possible on about 5-10% of the total harvested area and thus contribute with 1,3 - 2,6 TWh per year. An increase stump harvest doesn't come without its drawbacks for the environment. When harvesting stumps a tracked excavator is used to pry the stumps from the ground and then cut the stumps into smaller pieces.

Energibolagens framtida datainsamling

The Swedish energy companies have several different systems for data collection of the energy consumption of their clients. Often computerized remote meter readers are put in practice in order to register the energy consumption of large companies. The majority of household clients, however, are read off by the assistance of manual methods. Household power consumption is read off once a year. As a result, these clients are not debited for their actual consumption; their invoices during the year are the result of estimations. At times when the electricity supply system is highly loaded, electricity is more expensive.

Utvärdering av vattenrening och identifiering avförluster m a p energi vid Bravikens pappersmaskin 53

This Master degree project has been performed at the Braviken paper mill on papermachine 53 (PM53) which produces newsprint paper. The current economic situationhas contributed to declining demand for newsprint, which means it is extra important tobe competitive by high energy efficiency. Particularly as energy prices are expected torise when the economic growth returns.One way to increase energy efficiency is by reducing the water use in paper and pulpmills and consequently save energy through reduced heating of water. The thesis's maintask is to evaluate whether a water purification plant (microflotation plant) forpurification of process water in PM 53 is profitable. The microflotation plant enablesreuse of warm process water instead of losing the energy to receiving waters.

Solenergi på Kvarnholmen

In recent years it has become more and more evident that man has contributed to much of the climate changes that have taken place during the last century. A major challenge today is to reduce emissions and energy usage at the same time as the global population is growing. To contribute to a better environment, Stockholms Stad has set at target of becoming fossil fuel free by the year of 2050. The construction of new districts is done with this goal in mind; energy efficiency and renewable energy sources are examples of methods to achieve this.Solar energy is considered to be a sustainable energy source and the most common techniques to harvest solar energy in Sweden are solar cells and solar collectors which produce electricity and heat respectively. This report aims to investigate whether an investment in any of these systems would prove to be economically beneficial at Kvarnholmen, a district under construction in eastern Nacka, Stockholm.Since the finished blueprints only cover a small portion of Kvarnholmen, the report examines the possibilities for a house where construction has already begun, Nya Kvarnen.

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.

Håller vindkraften vad den lovar?

The purpose of this study is to investigate how much of the estimated annual electric energy production from Swedish wind power that actually was produced, as well as the history of this agreement over time. The aim is to also examine if there are properties that have caused some group of wind power plants to produce more or less, compared to their estimated production. Operational data on wind turbines collected by the Swedish Energy Agency was analyzed. A survey was made among owners of wind power plants with a nominal power of at least 2 MW. Two different methods for normal year correction of production data were used and compared.

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.

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.

Att göra demokrati : En kartläggning av forskningen om Botkyrkas demokratiarbete

By studying a place or a phenomena research contributes to the creation of the image of the thing that he or she studies. Also, planning is seen as a democratic tool, a way to ?make? democracy. In order to see what democratic ideals that is being express it becomes important to study the research about democracy in Botkyrka. It is from this thinking this study about democracy and research has been formed.

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..

Disclosure Tone in Environmental Reports ?A study of companies in the energy sector

Background and problem discussion: Sustainability reporting has recently risen in importance and a rising number of companies choose to issue voluntary stand-alone sustainability reports. Their non-regulated nature increases the opportunity for management to angle the information in these disclosures to their own advantage. Lately the focus has shifted from examining what kind of information is provided in environmental disclosures, to analyzing how the information is presented.Purpose: The purpose is to examine if managers in the energy sector use optimistic tone when issuing sustainability reports. The aim is to find out if the tone applied in environmental disclosures is in congruence with either the environmental or economic performance or if an excessively positive tone is being used to mislead readers.Limitations: This study is limited to information found in environmental disclosures from private companies in the energy sector, issued in 2012 or 2013. Environmental performance is defined as the amount of CO2e emissions and economic performance refers to annual company revenues.Methodology: The quantification of optimistic tone is conducted using a content analysis, relying on a pre-specified wordlist and a pilot study.

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