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311 Uppsatser om Solar cooling - Sida 12 av 21
Effektivt nyttjande av högeffektslysdioder i mobil belysning
The purpose of this master thesis has been to find different solutions to the design of a headlamp with a cluster of three or possibly four high power LEDs (Light Emitting Diodes). During the work, two different problems have been considered; how to design a lens in order to shape the light beam in a desirable way, and how to design a cooling system which will lower the temperature of the LEDs as efficiently as possible, still taking into account the geometry set by the optical solution as well as other given geometries. The results presented in this thesis are partly the outcome of a literature study, but derive mainly from a number of tests and measurements made on two test rigs and one concept prototype..
Framtidens energieffektiva flerbostadshus
The housing sector of today represents for almost 40% of the energy consumption, an energy consumption of which the major part consists of non-renewable energy sources. This is not sustainable and utilization of new energy-efficient technologies in buildings can be a step in the right direction, towards a sustainable energy society.This report has been made on behalf of and in cooperation with Älvstranden Utveckling AB in Gothenburg to examine how future energy-efficient technologies can affect the energy demand in energy-efficient multi-dwelling buildings.The report is based on Älvstrandens passive house, Hamnhuset, a house whose energy consumption is far below the BBR's requirements. The report looks at the opportunities for improvement within windows, insulation, solar energy technologies, as well as white goods. Computer simulations are then made to apply the selected technologies into a reference building. Technologies are selected from an energy efficient perspective and no account has been taken of other aspects such as the economy.
Energieffektivisering av befintlig bebyggelse med exempel från Göteborgsområdet
This thesis concerns to investigate renovations of existing buildings aiming at enabling energy efficiency, from a conservation and restoration perspective. This includes performing case studies of three projects in the Gothenburg area where renovations has been done and an analysis of directives raised by the EU and later implemented by the Swedish National Board of Housing, Building and Planning, Boverket. In addition to these, regulations enforced by the Swedish law, related to the topic, have been considered.The investigated projects in this case were the housing cooperative Välten in Brämaregården, the Solar Buildings in Järnbrott and Gårdsten as well as Katjas Gata 119 at Backa Röd. In order to measure and compare the results of these projects a comparison between the pre- and post-restoration energy consumption have been performed. To capture additional perspectives the grading system Operation Kungsörn has been applied.Regarding the comparison of energy consumption the renovation of Katjas Gata 119 was found preferable but showed in my view lacking attention to the cultural heritage of the area.
LAN-Uppgradering
The interest in small-scale electricity in Sweden has increased strongly in recent years. The interest is noticeable both among politicians to increase the share of renewables in the energy mix, and among electricity consumers to partially replace purchased electricity with self-produced. This has resulted in a significant increase of electricity production in low voltage grids in recent years, and the trend appears to continue in the coming years. The majority of the new production plants are solar cells, followed by wind turbines, and it is also in these the greatest efforts are made in this paper.Distributed generation is often seen as something positive since it will contribute to reduced transmission losses and reduced voltage drop in the networks, and that it increases the share of electricity from renewable sources. In cases where the grids are not strong enough, or in other ways not adapted to manage the installed production, power quality may be adversely affected.
Säkerhetsegenskaper hos en rymdreaktor
A Monte Carlo simulation of the ELECTRA reactor using (U,Zr)N fuel and a liquid lithium coolant is performed using the Serpent simulation code. The results show a reactor with a total reactivity coefficient of the coolant, fuel and material expansion that is strongly negative. These properties make the ELECTRA reactor a good candidate for a safe space reactor that could be used for propulsion of manned and unmanned space vehicles to Mars and other parts of our solar system..
Uppvärmningssystem : Ekonomi, miljö och drift
This bachelor thesis aims at investigate how a specified house can optimize its energy consumption.Today the house often stands for the major part of the energy consumption in a consumers? life,whereas an energy optimization creates economic as well as environmental advantages. It is importantto make old houses more energy efficient, but putting high energy demands on new houses could beargued to be more important. The installations functions as both the heart and brain in a house, thusmaking it important to energy optimize these. Since the background describes the importance ofenergy efficiency and optimization in a house, the focus area of this report will be an investigation ofdifferent types of heating systems in order to be able to choose the one most suited for the house.Aspects considered when choosing the heating system was how economic the system is both inservice- and investment costs and how environmental and operational friendly the system is.Through literature reviews there were sufficient information gathered that served as a foundation whencomparing and choosing between the four systems - district heating, pellet-fired boiler, geothermalheating and solar heating.
Hantering av småskalig elproduktion : Utveckling av modell för dokumentation och elkvalitetsberäkningar
The interest in small-scale electricity in Sweden has increased strongly in recent years. The interest is noticeable both among politicians to increase the share of renewables in the energy mix, and among electricity consumers to partially replace purchased electricity with self-produced. This has resulted in a significant increase of electricity production in low voltage grids in recent years, and the trend appears to continue in the coming years. The majority of the new production plants are solar cells, followed by wind turbines, and it is also in these the greatest efforts are made in this paper.Distributed generation is often seen as something positive since it will contribute to reduced transmission losses and reduced voltage drop in the networks, and that it increases the share of electricity from renewable sources. In cases where the grids are not strong enough, or in other ways not adapted to manage the installed production, power quality may be adversely affected.
Broiler production in Zambia - management, growth, diseases and welfare
Successful broiler production in hot climates requires knowledge of how birds are affected by heat stress. It is important with access to water and good ventilation to facilitate coping with the heat. It may be useful to reduce the consumption of feed during the hottest hours of the days, which together with a few hours of extra light available could improve both productivity and animal welfare.
The vision in birds is superior to that of humans and most other mammals. Continuous light and light with low intensity can cause eye injuries, affect the eye development in young chicken negatively, as well as provide increased incidence of foot pad lesions. Access to light affects the production but also the welfare of birds.
Dagsljusdesign för en god visuell miljö
During our education to become lighting designers at Jönköping University, the artificial lighting has been in focus. Therefore we wanted to learn more about daylight. We chose to do this from a visual approach in open plan offices. Since daylight is part of the architects´ responsibility to master, we wanted to examine what architects think of when they plan daylight environments in open plan offices and how this is expressed in the buildings with focus on the visual factors.Our questions at issue are:What knowledge do architects have concerning daylight planning, and how do they use this knowledge in their practice?How well do the chosen daylight environments meet the end-users need of a good visual environment? The study consists of three case studies, carried out in the same way.
Solel från ljudbarriär : längs Annetorpsvägen i Hyllie, Malmö
City of Malmö has ambitions for the district Hyllie to become a demonstrative area ofsustainable urban development. As a part of this the following report aims to investigate the potential in using noise barriers combined with photovoltaics along Annetorpsvägen to generate solar electricity. To quantify the losses that shadows from buildings along the roadmight cause, a 3D-model of the area was constructed in SketchUp. This digital model made it possible to simulate shadows and how they change over the year. A reference model of a photovoltaic noise barrier (PVNB) was constructed and used to find the dates on which the solar cells are shadowed depending on building heights and positioning of the barrier.The results show that two lengths with a total distance of 400 meters is appropriate for applying photovoltaic noise barriers.
Driva tulpaner i näringslösning eller i jord :
The aim with this thesis is to make a comparison between forcing tulips in a hydroponic system and the forcing off tulips that have been planted in soil. The results are mostly based on interviews with six Dutch and one Swedish tulip forcer and the managing director at the Horticultural Research Centre, Proeftuin Zwaagdijke, in the Netherlands.
There are benefits and disadvantages with both methods. Tulip bulbs planted in soil seem to get a brighter colour after forcing, compared with those forced ?in water?.
Aktivt system för tidvattenreglering av Lysekilsprojektets vågkraftsteknik
This report investigates a possible solution to the problem with adapting wave powerplants to work in countries with tidal water. The wire connecting the buoy at the surface with the generator at the bottom needs to adjust to the varying water depth. Our solution to this problem is to attach the wire to a jack which is then placed inside the buoy. The jack is then powered by an electric engine. The report discuss what forces the buoy will be exposed to and then the structural integrity of the design is evaluated through simulations.
Utveckling av Innovativa Småskaliga Elförsörjningskoncept : - Minor Field Study i Namibia
A large part of the Namibian low income population lack access to grid distributed electricity. This mean they are effectively shut out from basic functions such as lighting, information technologies and hygienic food handling. Hence, finding ways of providing affordable off-grid electricity is an important, not to say critical, task.This master thesis is an innovation and concept development project that has been carried out in cooperation with organisations in Sweden and Namibia. The purpose of the project has been to (1) develop a concept for off-grid electricity supply in Namibia and (2) to gain a deeper knowledge within the area of innovation and product development for the Base of the Pyramid population, i.e. the poorest, but largest, socio-economic part of the global population.Essential in this project has been to acquire user understanding and to identify user needs to create a foundation for developing the concept.
Hydraulisk och termisk grundvattenmodellering av ett geoenergilager i Stockholmsåsen
Geothermal energy can be extracted from an aquifer, where the groundwater is used as heatexchange medium while heat and cold are stored in the surrounding material in the aquiferand to some extent in the groundwater. Application of aquifer storage for the use ofgeothermal energy is mainly used in large scale facilities and is limited to sites with suitableaquifers in the form of ridges, sandstone and limestone aquifers.Löwenströmska hospital in the municipality of Upplands Väsby, north of Stockholm, islocated nearby the northern part of the Stockholm esker. This means that it can be profitableand environmentally beneficial for the hospital to examine the possibilities of aquifer storagein the esker material next to its property.The purpose of this master thesis has been to investigate if geothermal energy storage with aseasonal storage of heat and cold can be applied within Löwenströmska hospital?s propertyarea using groundwater modeling. A hydraulic groundwater model was constructed inMODFLOW based on a simplified conceptual model of the groundwater system.
Strömmande video i trådlösa mesh nätverk : Streaming video in wireless mesh networks
This document?s content is the final report of the master´s dissertation Magnus Hällström did during springtime of year 2013. The dissertation?s subject is 802.11s wireless mesh networks with streaming video as a focus point. During the dissertation a wireless mesh network was set up with different attached cameras for streaming video. A sun panel solution was also tested with the goal of creating a package with a self-configuring network node streaming video, powered by nothing but solar energy. .