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4212 Uppsatser om Energy Systems - Sida 36 av 281

Energiberäkningar för passivhus

AbstractClimate and environmental issues are of paramount importance. Researchers agreethat we must all contribute to a reduction of gases that contribute to climatechange. Energy consumption must decrease within all sectors and the promotionof renewable sources of energy must be introduced.Each sector should aspire to decrease its energy consumption. Energyconsumption is strongly linked to waste gases that contribute to climate change.Passive houses are a part of the construction industry's methods to attain energyconservation.Passive houses are derived from low energy houses and super insulated houses. Apassive house is intended to obtain heat from the inhabitants and through theiractivities.

Lagring av kyla i bergrum : Undersökning av ett nedlagt oljebergrum

This thesis considers the use of an oldrock cavern as thermal energy storage.With a large system of differentchillers a model was created to find anappropriate future system. There aremainly two trajectories to take. Eitheran installation of chillers needs to bemade or the rock cavern can be used tomeet the future demand of districtcooling in Solna, Sweden. Additionallythis thesis investigates the possibleuse of different techniques to utilizethe phase change energy of water.Simulation shows that it?s possible toutilize the phase-change energy of afluid; however it?s not economicallyfeasible due to the thermodynamiceffects on the Carnot cycle.

Solvärme med säsongslager i Lyckebo

The purpose of this thesis is to investigate and clarify the facts surrounding one of Vattenfall's district heating plants; The "solar field" and associated rock cavern in Lyckebo, Storvreta. The plant was built in the '80s by the formerly municipal utility,Uppsalakraftvärme AB, as an experimental building. A ground water filled cavern would serve as seasonal storage of solar heat from an adjacent solar field. Since both the energy company and the facility itself has undergone major changes over the past 30 years, there was a great need to gather facts in order to provide a picture of its current condition and potential for continued use. The thesis investigates the plant's history and problems with the rock cavern losses, and how the operation developed. It also presents the calculations regarding the possibilities of again supplementing the facility with solar energy - which is not the case today - as well as the economic conditions for it. Regarding a re-launch of solar energy, primarily a concentrating solar collector has been studied, as it has the advantages of an integrated control system.

XML som informationsbärare för EDI

Information handling has been a key issue for different companies for a long time. Electronic Data Interchange (EDI) is used to transfer different business documents from one company to another. This is done in such way that the information itself is separated from how this information is stored and handled in the companies internal systems. As different companies have different systems there is a need for a standardised format for this exchange. There is a big difference between EDI-systems based on what kind of EDI-standard is used. The most common standard in Europe is EDIFACT, but with increased interest of using the Internet for business communication there is a need for a standard that is adjusted for use over the Internet.

ScenÖsterlen. Kulturprojekt för barn och ungdomar - betydelsefullt i en mindre kommun?

AbstractThe future of ethanol is depending on good solutions for the production. ENA energy power plant produces electrical power and district heating by heating biofuel. By building an integrated bioenergy plant surplus steam could be used to produce ethanol as fuel to vehicle.This would mean that ethanol is produced renewable energy and the energy for the process derives from the surplus of power.  ENA energy, MDH (the University of Mälardalen) and the energy authority has initiated a research project were different bioenergy combinations integrate with existing power plant.  As a part of the project which size an integrated factory should be to gain the best efficiency for the plant was investigated. Consideration will be taken to the cost of the production in order to be competitive to the price of imported ethanol.  Etanolens framtid vilar på bra lösningar för framställning.  I ENA energi kraftverk i Enköping produceras el och fjärrvärme genom eldning av biobränsle.  Genom att bygga ett integrerat bioenergikraftverk där skulle man kunna använda överskottsånga till att framställa etanol som fordonsbränsle.

Systematiserad erfarenhetsåterföring inom byggbranschen. Ett arbete för att minska återkommande produktionsfel inom Tuve Bygg.

The climate changes that are occuring in the world have resulted in that the EU callingfor a 20 % reduction in energy consumption to the year 2020, to reach that goal theEU want the public sector to go forth as a good example. Västfastigheter owns andmanage the hospital buildings in the Västra Götaland region. To be able to reducetheir energy usage Västfastigheter has hired several consulting firms to chart out theenergy consumption on each hospital building. The biggest energy savings potentialhave been calculated and what the cost will be to perform each action. The energyaudit have been completed and stand as the decision basis for Västfastigheter?s choiceon which action packages that should be implemented.

Den svenska kärnkraftspolitiken : En processpårande fallstudie av svensk kärnkraftspolitik

This study deals with Swedish nuclear-energy politics from 1980 to 2006. The purpose is to trace and to explain change and stability in three political parties? rhetoric concerning the phase-out of Swedish nuclear-energy and the Swedish government?s nuclear politics. Two hypotheses based on path dependency theory are tested to analyze if rhetoric and politics are developing in separate directions. The first hypothesis is based on the idea that earlier promises from the political parties affect what promises they can make later on.

Användarkontohantering : Analys av användarvänlighet

Password Management Systems är system som hjälper användaren skapa kontroll över sinaanvändarkonton och lösenord. Denna studie analyserar tre utvalda system, hur användarvänliga de är samtvilken typ av autentisering och kryptering de använder. Metoden som används är experiment tillsammansmed intervjuer av fem deltagare, varav alla hade olika erfarenheter med datorer. Studien har visat attanvändarvänligheten bland flerparten av systemen är höga. Risker finns bland upprepade lösenord ochanvändarnamn, samt osäker autentisering.

Optisk sortering av matavfall : en jämförelse med en minskning av svinnet

The purpose of this study is to compare the energy related and environmental consequences of implementing optical sorting as a means of waste collection with those of reducing food waste. In addition to studying the possibility of implementing optical sorting in downtown Stockholm, the yielded amounts of energy from waste collection and reduced wastage will be calculated. This is done by way of literature reviews and interviews. The amount of energy that can be generated through optical sorting and biogas production via anaerobic digestion in downtown Stockholm is 29-44 TJ/year, compared to 118 TJ/year saved by completely eliminating food waste. The generated biogas can replace fossil fuels, but the required food waste contributes to increased greenhouse gas emissions as well as reduced bio diversity and eutrophication during the wasted food?s lifecycle.

Termoelektrisk lagring i system med fjärrvärmeproduktion

With increased deployment ofintermittent renewable energy, such aswind and solar power, energy storagebecomes necessary to help reduceproduction peaks. Thermoelectric EnergyStorage is a method still in researchphase, which stores electricity in hotwater at a temperature of 120 ° C. Thisthesis aims to examine whether theThermoelectric Energy Storage would bepossible to integrate into existingpower generation such as a combined heatand power plant, and how the technologypotentially could function in theelectricity market. ThermoelectricEnergy Storage consists of a chargingprocess and a discharging process, bothoperating by the working fluid CO2. Toincrease the efficiency of theThermoelectric Energy Storage, wasteheat from the district heating networkis integrated.A model of the Thermoelectric EnergyStorage has been developed and it wascalculated by thermodynamic propertiesof the working fluid, CO2, in thevarious process steps.

Budgetstöd : relationen till de svenska biståndspolitiska målen: att skapa förutsättningar för de fattiga att själva driva sin utveckling, uppnå jämlika förhållanden mellan givare och mottagare och fattigdomsbekämpning

There's no doubt today that mankind has contributed to the changing climate byher use of fossil fuels. This must change in the nearby future. The Europeanleaders are expressing concern that renewable energy sources are not beingused to their full potential. The 2001/77/EC Directive on Electricity Productionfrom Renewable Energy Sources was accepted in 2001 to encourage thedevelopment of energy production from renewable sources, which isconsidered a step towards the fulfillment of the goal of the Union, that 12% ofthe gross energy consumption should come from renewable energy sources bythe year 2010.The objective of this thesis is to illuminate the common legislation of the EUregarding renewable energy with regard to goal fulfillment, judicial quality,conflicts with other goals of the EU and other faults. The objective is reachedby a hermeneutic study in which interpretation of written text is the mainmethod.

Rökgaskondensering och skrubber till vedeldade villapannor :

This paper deals with the opportunities for the technique of condensation, for wood fired household heaters, on the Swedish market. In this project the condenser is preceded by a scrubber and both energy exchange and separation of unburnt particles have been studied. The facility studied is connected to a wood stove at 30 kW. The tests would show that the effect from the stove never reached above 16 kW. This might be a result of the low temperature of the water going into the stove, from the condenser. In addition to this the wood was not of highest quality and the stove could have needed some maintenance before the tests.

Småskaligt vattenkraftverk i Nyköpingsån

Interest in alternative energies is high in Sweden today, particularly in the agricultural sector. According to the Swedish lantbruksbarometern (2009), almost all respondents consider the use of some form of alternative energy from the farm. While interest in alternative energies is large, attention to the alternative energy straw has fallen and is almost nowhere mentioned in the literature today. Three years ago, in the Lantbruksbarometern nearly 44% of the farmers would be willing to invest in straw as heating system on the farm. How do the farmers decide to invest in alternative energies? With this information a problem is presented for this paper.

Planering, förutsättningar ocheffekter av implementering avsolceller i stadsutvecklingsprojekt.

Today, buildings utilize 40 % of the total energy consumption. New energyrestrictions and directives have entered the construction industry. Photovoltaic is asustainable, clean and quiet solution that integrates well in the urban environment buthave not yet reached a breakthrough on the Swedish market. The conditions for solarenergy production are often set in the early planning stages where they rarely arebeing prioritized.This master of engineering project focuses on identifying problems regardingimplementation of photovoltaic in city development projects and giving suggestions topossible improvements in the planning- and construction process. It also givesrecommendations on how the conditions for energy production can be optimized inthe early zoning stage.By conducting simulations with PVsystV5.21, on three ongoing city developmentprojects in Umeå, Malmö and Stockholm and by carry out and analyzing interviewswith city planners, constructors and architects, some conclusions have been made.Several improvements, both politically, with changes in the subsidization systemand/or instatement of a new law with feed-in tariffs, and within the solar- andconstruction industry itself, with better communication between different parts of theprocess as well as better use of experience, can be made.

Renovering av miljonprogrammet till Umeå kommuns nybyggnadskrav för energianvändning

A lot of houses built during the Million Homes Programme are in need of major renovation. Today?s technology and materials are better than in the 60?s and 70?s. Both Swedish government and the European Union have set climate goals regarding energy consumption by 2020 and 2050. Achieving these goals would require better standards in buildings than the Building regulations demands, such as Umeå municipality?s construction requirements for new buildings.The report aims to investigate if a renovation of apartment buildings from the Million Homes Programme can reach Umeå municipality?s construction requirements.

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