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2005 Uppsatser om Borehole thermal energy storage - Sida 6 av 134
Konceptstudie av Waste Heat Recovery System på Tunga Fordon
In today?s fast growing and closely connected society, a reliable and energy efficient transportation system is more than ever desirable. Nowadays the significant part of the transportation sector?s energy demand is supplied by fossil fuels.Improving energy efficiency in combustion engines will result in reduction of fuel consumption and CO2 emissions. A modern internal combustion engine has an efficiency of 30-45 %, where the most energy loss occurs as result of heat losses in the exhaust and cooling systems.
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.
Utvärdering av energieffektiviseringsåtgärder på Bokelundskolan i Växjö
The purpose with this report is to examine how the implemented energy efficiency measures on Bokelundskolan in Växjö have had impact on the energy use. The measures which have been implemented are, new ventilation system, new heating system, optimized adjustment of the heating system, new windows with U-value 1.2 and lower window height, insulation under windows and in the crawl space. The school's energy use before and after rebuilding has been calculated with the calculation program, Vip-Energy 1.5.5.Calculations of energy use for the school with windows on U-value, 0.9 and 0.7 have also been done. The replacement of windows has been studied from a cost perspective. The conclusion is that the exchange of heat and ventilation system was the biggest contributor to reduced energy use on Bokelundskolan.
Metodik för identifiering av T-stycke med risk för termisk utmattning
Thermal fatigue is a serious problem in todays power plants. A large amount of damages around the world circles around that subject. The damage can come from the mechanism of two flows mixing with different temperatures in a T-junction. It is a fundamental prerequisite that these T-junctions are frequently tested for damages. An amount of criterias steers the rate of testings.
Inverkan av Kiselhalten på Värmeutvidgningskoefficienten hos Aluminiumlegeringar
The purpose of this report is to document the experiments carried out, methods used and results gained during research into how the silicon content of an aluminium alloy affects the coefficient of thermal expansion (CTE).The goal of this paper is to better understand and to find a relation between silicon content and the coefficient of thermal expansion.Experiments were carried out using carefully prepared samples of Al Si alloys (0, 7, 10 and 20% Si content). Using these alloys, the CTE could be measured using a dilatometer.Comparative analysis carried out could map the effects of silicon content on the coefficient of thermal expansion and an equation was created. Using simple graphs and the rule of mixture method, the authors were able to build a simple tool for calculating the CTE of specific aluminum silicon alloys..
Grinda Wärdshus : Hållbara Isoleringsmöjligheter förVandrarhemmet på Grinda
pelago. There is an old inn that is located on the island that has become a very popular attraction in the last couple of years. The inn has both a well-known restaurant as well as conference facilities that are used by tourists as well as the people of Stockholm over the summer months. The inn was built 1908 and has since remained in the same condition.make islands in the archipelago more environmentally friendly and promote sustainability. One of their project islands is Grinda.
qbits : Kombinerar användning och förvaring av bits
Aren?t you tired of never finding stuff? Take a bits as example, do you store these lose in your toolbox or carpenter belt? What if you could have it all accessible and assembled in a tool, always at arm?s reach?Today bits are used together with electric screwdrivers and handheld screwdrivers in a greater spread. For these different types of storage, from pure storage boxes to complex tools with storage built in, exist. The professional craftsmen commonly use some kind of box where the bits can be stored. Even so they tend to store their bits loose in a carpenter belt or toolbox, since they want the speed and accessibility of carpenter belt over the storage box?s tidiness.The project was started in the fall of 2010 and a referents group was early put together to ensure that the developed product became as user-friendly and attractive as possible.
Konsumentvänlig Energibesparingsmodell : Ett verktyg som hjälper småhusägare att sänka sina energikostnader
Energy awareness is growing among the Swedish population and a one?to?two-family dwelling can save energy. The purpose of this paper is to design a tool that helps these home owners reduce their energy costs.The paper develops a model that gives them an indication of how much energy they can save. For the majority of homeowners, the next step in the quest to reduce theirs is most likely an energy audit. Therefore, information to help home owners to get a good energy audit performed is included in the model.A prototype running the operating system iOS is created and validated against existing models, as well as an energy audit. .
Energieffektivitet och kvalitet på inomhusluft i radon förorenade bostadshus
To build a sustainable future should we first understand that; every aspect of our daily lives can affect the environment. It?s important that we take responsibility for understanding how we impact the environment and change our actions accordingly. The worlds total energy consumption equivalent to 80 million MWh / year. This corresponds to about 220 million MWh / day.Energy consumption is one of the main reasons for increased greenhouse gases when the reduction of this consumption has a great demand worldwide.In order to prevent the energy that consumed the buildings must be energy efficient but there is a conflict between radon ventilation and energy conservation in a building, given that ventilation can consume as much energy (currently 29-59% of energy-efficient houses use), especially in a cold climate as in Norway.
En energiutredning och miljöklassning av Hemsta 12:16
The purpose of this study was to implement an energy analysis and environmental evaluation of the property Hemsta 12:16 in Gävle. Based on two different methods, Energy Balance calculation and Environmental Building, the result of the property's energy use, energy performance and environmental impacts are presented. Except that, measures to reduce final energy consumption are presented. The proposed measures can reduce energy usage by 100 400 kWh / year, which represents a decrease of 18% of the present energy usage. This would represent a total savings of 63 000 SEK per year. In addition, the environmental performance is improved by adopting the suggested measures..
Termisk hantering av litium-jon- batterier i elektriska drivsystem
The automotive market is currently undergoing a historical change where stricter emission legislations and ever increasing fuel costs have intensified the search for effective alternatives to the conventional internal combustion engine, which has resulted in a substantial trend towards electrification of powertrains. Storage of electrical energy is the fundamental component in this technology where the lithium-ion batteries are currently considered as the most appropriate solution. Lithium-ion batteries, however, as other types of batteries, can only be used efficiently and durably within a specific temperature range.This Master thesis has been carried out in collaboration with Electroengine in Sweden AB, situated in Uppsala, which has an ongoing project regarding development of a modular battery system for electric powertrains. The project is at a stage where an initial prototype has been developed which provides the foundation for this thesis. The study has addressed the battery system performance from a thermal perspective, in order to validate the ability of the system to create a thermally serviceable environment for the lithium-ion battery cells.
New Business Model for District Heating Firms Stabilizing the National Energy System with a Future Variable Electricity Production
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.
Solcellsdrivning av distribuerade inbyggda system
The high level of energy consumption that the industrialised countries have reached and thepollution that this brings has long been a cause for analysis and debate, development and usageof so called renewable energy sources is therefore more important than ever. The energy in theelectromagnetic radiation from the sun is an interesting alternative. One way of harvesting thisenergy is by using solar cells, devices that generate DC current when exposed to electromagneticradiation.The goal of this master?s thesis was to design a solar powered power supply to Syntronic AB?sMidrange platform. The envisioned application is a stand-alone distributed embedded system,for example a node-based temperature monitoring system.
Utvärdering av befintliga passivhus : En byggnadsfysikalisk bedömning och mätningar om temperatur, och fukt analys på ytterväggarna
Energy price are on the way up to a high level that will not diminish in the future make us to focus more on the sustainable development for a better solution of residential houses. Passive house or low energy housing are one of the solution to make residential more environment friendly, in same time it´s a financial security using less energy, and saving money. The last 10 years in Germany and all around Europe the concept of passive house been developed, and people aim to know more about these concept that leading the market more attractive for passive houses. A passive house is a well designed building highly insulated and air tight with mechanical ventilated system for the whole building envelope that minimizes the use of energy for heating [1].The housing company Mimer has chosen to invest in low energy consumption in every new housing project. These future plan projects are decided to use less than 75 kwh per square meter annually in purchased energy [2].This thesis is about new constructed passive houses, and focuses on the evaluations of the temperature, and moisture condition for attic, external walls and joist.
Energikartläggning och energieffektiviseringsåtgärder i Zoologen på Göteborgs Universitet
The question of excessive global energy use needs to be solved. All energy production and usage have negative environmental impacts, which are best solved by reducing energy consumption and by using energy more efficiently. A large part of the Swedish energy use is concentrated to the building sector and to reduce the total energy consumption real efforts need to be made to make buildings more energy efficient.The aim of this study was to investigate how energy is used in one of Göteborg University?s buildings and to find measures that can be taken to improve its energy efficiency. The chosen building Zoologen, is used for research and education.The main method of the study is computer simulations of the present building and of possible energy reducing measures to be made in the future.