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1692 Uppsatser om Excess energy - Sida 59 av 113
Optisk karakterisering av tunna SiO2/NiO-filmer syntetiserade med en sol-gelmetod
In an attempt to develop a more cost-efficient material for solar energy applications, nano-particles of nickel oxide composite in a silikatmatris manufactured with solar gelmethod and studied structurally by electron microscopy. Furthermore, the thin film optical properties characterized by Variable. Angel Spectroscopic Ellipsometry. Sol gelfilms suitability as a selective absorber surface is also analyzed by optical modeling..
Miljöbyggnad i ombyggnadsprocessen : Miljöcertifiering av Jakobsbergsskolan i Kristinehamn
Climate change is an increasingly widely known concept. In the EU the construction sector is responsible for more than a third of the carbon dioxide emissions and 40 % of the total energy use. In Sweden, measures have been taken to prevent this climate change. By 16 targets, three of which can be linked to the construction sector, Sweden will reduce the negative trend. None of the three goals with relation to the construction sector will however be achieved before 2020.
Environmental impact assessment of energy recovery from food waste in Singapore : comparing biogas production to incineration
As a small and land scarce country, effective waste management is ofoutmost importance in Singapore. In this study the production of biogasthrough anaerobic digestion from the organic fraction of municipal solidwaste (OFMSW) was compared to incineration of the waste. At the momentalmost all of the OFMSW in Singapore is incinerated. Three differentscenarios were compared to the reference scenario (incineration): one with alarge scale biogas plant that can treat half of all OFMSW in Singapore, onewith a medium scale biogas plant about 15 times smaller than the large oneand one with a small scale biogas plant that can treat waste from e.g. ashopping center or a food center.By using life cycle assessment (LCA) the different scenarios were comparedin terms of global warming potential (GWP), acidification, eutrophication,energy use and land use.
Värmeöverföring i bergvärmesystem : En numerisk analys av den ringformade koaxiala borrhålsvärmeväxlaren
The borehole heat exchangers of today suffer from poor thermal and hydrodynamic performance. The purpose of this thesis is to improve the performance of ground source heat pump systems and thermal energy storages by increasing the energy efficiency of the borehole heat exchangers. For this reason, the annular coaxial borehole heat exchanger (CBHE) has been analyzed. This type of heat exchanger is interesting in terms of both thermal and hydrodynamic performance. A model has been set up in the program Comsol Multiphysics in order to investigate the heat transfer characteristics along the borehole.
Designerrollen i en webbdesignprocess
This study investigates if, and in that case, how design theory is applied in practice in the web development field. Prior research has focused on methods used in the web development field. We wanted to study the designers role in a web design process by comparing existing designer roles with design theory literature. We did qualitative interviews with two practitioners at two different communication agencies in northern Sweden. Based on our qualitative data and literature review we have concluded that a designer has to devote a lot of energy on requirements engineering in order to develop a clear understanding of the design situation..
VÄRDERING OCH REDOVISNING AV FÖRVALTNINGSFASTIGHETER I KONJUNKTURNEDGÅNG
In the year of 2005 the international standard IAS 40 came in to use in Sweden, this lead to an opportunity for the corporations to choose either to evaluate their investment properties according to the historical cost accounting principal. The model contains the obtaining price with reduction for the planned writing off. The alternative that IAS40 offers is the fairvalue principal, which evaluate the investment properties by consideration of the income versus outcome and surrounding factors for every accounting periodSince the fairvalue is buildt on numbers the corporations them self choose what to publish and for how long the value depreciation should be lasting before it should be taken up as an unrealized value change in the reporting material. This means that there is a big chance that the evaluation can be distortedSince we just recently have had strong cyclical variation and are on our way from an excess boom into a weak economic climate, this will be the first study performed about fair value in a weak economic climate since the adoption of IAS40.The purpose of the essay is to find out how well the booked value of investment properties owned by corporations listed on the Swedish stock market accord with the fairvalue that the market and the Swedish property index indicates on. To be able to test this connection we gathered information from the corporation?s annual reports which we compiled to see how the market comprehends.
Effektiv lagerstyrning genom tillförlitlig prognostisering : Effective inventory control through reliable forecasting
This study was done regarding whether sealing or ventilation is the best solution to prevent moisture on cold attics. The authors of this report addressed the problem with moisture in attics when they started their cooperation with Peab.The methods included interviews with people, database research, and calculations of a project in Akersberga north of Stockholm. The conclusion is based on interviews and other information as they are analyzed in relation to the house of reference. The focus of this report is on problems with moisture in the attics known as cold attics.The background of the problem with moisture is that today?s slabs are usually insulated to save energy and that the attics nearly gives the climate as the outdoor climate.
Landskapsplanering ur ett hållbarhetsperspektiv :
Environmental problems are accelerating with energy consumption and the release of greenhouse gases as the major issues. This affects landscape planning mostly through environmentally hazardous transportation and heating of buildings. In environmental work, the term "Sustainable development" is often used. This term was coined in the Bruntland report in 1987. A number of frameworks have been developed to clarify the term and to remind the user about relevant aspects of sustainability.
Fireball 2 : Energieffektiv fiber produktion
The development within the textile industry is always ongoing with development of new andbetter textiles, which often mean the use of non-natural materials like polyester. This doesn?t lineup with the work shared around the world against an improved environment, so the idea came touse a form of linen fibers instead of polyester as the reinforcing material together with cotton.The idea was to use flax, linen of low quality, which is seen as a waste product and garbage inthe production of high quality linen and flax seed oil. This flax of low quality needs to beseparated before it can be used in cotton spinning machines. Fireball 2 is just that, a process toseparate flax fibers through the treatment of a technique called electrohydraulic discharge.The thesis works goal is to evaluate the Fireball 2 process ability to separate flax fiber.
Pre-treatment of grain for ethanol production during storage
Ethanol for automotive purposes is an issue much debated and researchers disagree about the benefits of bioethanol. Converting energy-rich crops into ethanol suitable as motor fuel is a complex process and continuous development and improvements of processes and material used are important steps in the work of developing environmental friendly fuels. Grain is usually preserved by drying which consumes a lot of energy. Alternative storage of high-moisture grain in airtight storage systems reduce the energy required to produce bioethanol and studies have also shown that ethanol yields are increased more than 10% in ethanol fermentations of moist grain compared to dry. Airtight storage is often not perfectly airtight so biocontrol agents are necessary in order to preserve the grain.
Fukthalt i GROT - påverkande faktorer :
This study was carried out at the request of the bio energy company Naturbränsle. The company handles annually 750 000 m3 of chips from logging residues from a large area, from Östergötland in the south to Härjedalen in the north. In that area, about 50 bio fuel plants are customers. When Naturbränsle deliver chips from logging residues to their customers, the moisture content varies from 30 % to 60 %. The aim of the study was to sort out the affecting factors on the moisture content in the chips during handling and storage processes.
Undersökning av energibesparande metoder för multiplikator
In this thesis a number of energy saving methods for a multiplier on algorithmic level are investigated. For the investigation a multiplier is constructed in VHDL, after which the circuit's performance is investigated. A number of techniques for reduced power consumption are introduced in the circuit and are then evaluated. The conclusions are that all investigated methods, pipelining, interleaving and voltage scaling, should be maximally made use of in order to minimize the power consumption..
Beräkning av byggnaders energiprestanda med anledning av energideklarationerna.
Europaparlamentet antog i december 2002 ett direktiv om byggnaders energiprestanda.Direktivet kräver att byggnader skall energideklareras, alltså undersökas och dokumenteras urett energiprestandaperspektiv. Direktivet har hittills resulterat i två svenska delbetänkandensamt ett slutbetänkande. Dessa tre skrifter kommer att ligga till grund för den svenska lagenom energideklarationer. Enligt SOU 2005:67 skall energiprestandan beräknas för samtligasmåhus och nybyggda hus. För flerbostadshus och byggnader med lokaler skallenergiprestandan beräknas då det inte finns några uppgifter på byggnadens energianvändning.Eftersom byggnaders energiprestanda är en central del av energideklarationerna ägnas det enutförlig analys av olika energiflöden ut ur och in i en byggnad.
Energieffektivisering genom ombyggnad : Med hjälp av VIP-Energy
Detta examensarbete har genomförts i samarbete med Värmex AB där vi har haft Anders Ericsson som handledare, och Peter Hansson (Sweco) som handledare från skolan, Kungliga tekniska högskolan i Haninge.Idag är energianvändningen i flerbostadshus en stor fråga att ta itu med, och för varje byggnadsprojekt skall en energideklaration som visar mängd köpt energi göras. Vi strävar idag efter att minska energianvändningen i flerbostadshus med 50 % till 2050. I denna analys beskriver vi vilka åtgärder man kan ta an för att minska just energianvändningen i ett specifikt flerbostadshus belägen i kommunen Nacka i Stockholm.Då denna byggnad stått från år 1949 utan större underhållning har det visat sig att byggnaden står över BBRs krav gällande energianvändning (90 kWh/m2), och stor anledning är klimatskalet. Källor visar även att delar av klimatskalet så som fasad etc. bör ändras inom 30 år efter det att det byggts, vilket inte har gjorts.Vi har genom en programvara, VIP-Energy valt att utföra denna analys.
Beräkning av baslinje för Performance Contracting med linjär regression
Energiutvecklingsprojekt är idag mer aktuella än någonsin. För att kunna genomföra så stora projekt som hela fastighetsbestånd, och samtidigt ta hänsyn till lagen om offentlig upphandling har affärsmodellen EPC, Energy Performance Contracting, utvecklats. I samarbete med SIEMENS AB Building Technologies har jag tittat på hur man kan garantera en viss nivå på besparingarna som genomförs. Denna garanterade besparing beräknas mot en uppställd baslinje, som är en beräkning av hur energianvändningsmönstret skulle ha sett ut med dagens förutsättningar om inga förändringar gjorts. Modellen med regression är noggrann och hjälper till att identifiera avvikande användningsmönster..