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1951 Uppsatser om Energy- effectiveness - Sida 33 av 131
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.
Barnanpassade söktjänster på Internet
The purpose of this study is to investigate childrens possibilities to retrieve information by searching in searching engines designed for children. Two such search engines are examined: Yahooligans and Kids Click, both of which index pages in English only. I have compared Yahooligans with its equivalence for adults; Yahoo, by evaluating the retrieval effectiveness. Some functions in Kids Click and in Yahooligan are investigated. Seven class room studies are described in the prior research chapter.
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..
Värdet av att bygga grönt för kommunala bostadsbolag
AbstractThe real estate sector is today responsible for 40 per cent of the total amount of energy consumption within the members of the EU. All over the world there are collaborations within research and projects to find ways of reducing the amount of energy consumed by the real estate sector. In Sweden, a directive from the European Union has posed demands on authorities as well as on the private sector to reduce the amount of energy consumed by new building constructions. Together with the directive from the EU there are also new requirements and demands from Boverket for the real estate sector. These requirements mostly concern the energy consumption of kilowatt-hour per square metre and that the consumed energy also should be renewable. The aim of this study is to explain what kind of value municipalities experience in using certifications and environmental investments for new and existing buildings. Within the chapter theory, essential areas are described such as; environmental certification systems, economical viability, proceeds connected to building green, difficulties with building green, the performance of green buildings when affected by the behaviour of tenants and customer value. The following chapter describes the methodology with which we have conducted this study.
Beskrivning av fel och brister på broräcken och förslag till förebyggande åtgärder avseende tillverkning och montering
On a request from the water sewage plant Gryaab in Gothenburg a power quality survey was performed. The voltages and currents have continuously been sampled in the incoming 10 kV substation HSP01 from April-August 2008. Power quality measurements were also performed in Gryaabs other 10 kV substation HSP04 fed from HSP01 and at the terminals of the induction motor IN_PU4040 of 1.3 MW which controls one of the four large inflow pumps to the plant. The reason for the latter measurement was due to registered negative transients each time the motor was connected to the grid. The cause of the transients could be explained by the coupling in the substation, the ageing of the motor which could result in damage of the bearings or resonance in the motor circuit which amplifies high frequency harmonics.
Sättningsberäkningar I kalkcementpelarförstärkningar. Jämförelse mellan mätningar och beräkningar enligt Allmän teknisk beskrivning
On a request from the water sewage plant Gryaab in Gothenburg a power quality survey was performed. The voltages and currents have continuously been sampled in the incoming 10 kV substation HSP01 from April-August 2008. Power quality measurements were also performed in Gryaabs other 10 kV substation HSP04 fed from HSP01 and at the terminals of the induction motor IN_PU4040 of 1.3 MW which controls one of the four large inflow pumps to the plant. The reason for the latter measurement was due to registered negative transients each time the motor was connected to the grid. The cause of the transients could be explained by the coupling in the substation, the ageing of the motor which could result in damage of the bearings or resonance in the motor circuit which amplifies high frequency harmonics.
Återladdning av borrhål i Borås Djurpark. En studie om möjligheter att kombinera solfångare med ett befintligt bergvärmesystem
On a request from the water sewage plant Gryaab in Gothenburg a power quality survey was performed. The voltages and currents have continuously been sampled in the incoming 10 kV substation HSP01 from April-August 2008. Power quality measurements were also performed in Gryaabs other 10 kV substation HSP04 fed from HSP01 and at the terminals of the induction motor IN_PU4040 of 1.3 MW which controls one of the four large inflow pumps to the plant. The reason for the latter measurement was due to registered negative transients each time the motor was connected to the grid. The cause of the transients could be explained by the coupling in the substation, the ageing of the motor which could result in damage of the bearings or resonance in the motor circuit which amplifies high frequency harmonics.
Föroreningstransport med dagvatten - Utveckling av reningsmoduler för modellverktyget Mike Urban SWQ (Storm Water Quality)
On a request from the water sewage plant Gryaab in Gothenburg a power quality survey was performed. The voltages and currents have continuously been sampled in the incoming 10 kV substation HSP01 from April-August 2008. Power quality measurements were also performed in Gryaabs other 10 kV substation HSP04 fed from HSP01 and at the terminals of the induction motor IN_PU4040 of 1.3 MW which controls one of the four large inflow pumps to the plant. The reason for the latter measurement was due to registered negative transients each time the motor was connected to the grid. The cause of the transients could be explained by the coupling in the substation, the ageing of the motor which could result in damage of the bearings or resonance in the motor circuit which amplifies high frequency harmonics.
Norra Djurga?rdsstaden som nollstad : En studie av miljo?projektets sista etapp och dess potential
All around the world more and more people move from rural areas to live in the cities. Because of this, the urban areas have become an important part in the debate about the effects on the environment and sustainability. In many countries word wide initiatives have been taken to build sustainable cities and eco cities, the Stockholm Royal Seaport is one example. The vision for the district is to become a world class sustainable city based on the three dimensions of sustainable development: social, economic and ecologic. The municipality of Stockholm has set requirements for the buildings? energy usage, emissions and amount of waste generated during the building process.
Effektivisering av dataflödet mellan anläggningsmodell och maskinstyrning - En översikt av flödet från konsult till entreprenör
On a request from the water sewage plant Gryaab in Gothenburg a power quality survey was performed. The voltages and currents have continuously been sampled in the incoming 10 kV substation HSP01 from April-August 2008. Power quality measurements were also performed in Gryaabs other 10 kV substation HSP04 fed from HSP01 and at the terminals of the induction motor IN_PU4040 of 1.3 MW which controls one of the four large inflow pumps to the plant. The reason for the latter measurement was due to registered negative transients each time the motor was connected to the grid. The cause of the transients could be explained by the coupling in the substation, the ageing of the motor which could result in damage of the bearings or resonance in the motor circuit which amplifies high frequency harmonics.
Inventering av bitumenbundna lager med hög stabilitet ?hård asfalt? anpassade för stora hjultryck på industri- och hamnytor
On a request from the water sewage plant Gryaab in Gothenburg a power quality survey was performed. The voltages and currents have continuously been sampled in the incoming 10 kV substation HSP01 from April-August 2008. Power quality measurements were also performed in Gryaabs other 10 kV substation HSP04 fed from HSP01 and at the terminals of the induction motor IN_PU4040 of 1.3 MW which controls one of the four large inflow pumps to the plant. The reason for the latter measurement was due to registered negative transients each time the motor was connected to the grid. The cause of the transients could be explained by the coupling in the substation, the ageing of the motor which could result in damage of the bearings or resonance in the motor circuit which amplifies high frequency harmonics.
Söktjänster för akademiskt bruk. En jämförande undersökning mellan Google, Google Scholar och Scirus.
This paper is a comparing study of the retrieval effectiveness of the search engines Google, Google Scholar and Scirus. The aim is to find out how good they are at retrieving relevant academic material in the research-field of Library and Information science. The thirty search questions where based on actual information needs collected from exams within the field of Library and Information Science. This method was used to prevent that none of the search engines were given an advantage because of construction of the information needs. The first twenty retrieved documents on the retrieval lists are examined for academic content and relevance.
Energisystemanalys av ABB AB LV Motors
With a larger awareness of the climate changes and increasing electricity prices, energy efficiency measures in the industry have become more common. By rationalize the activity and by the same time decrease the emission of greenhouse gases the company can both save money and reduce negative environmental impact. For the Swedish industries the electricity price have traditional been relative low, which has resulted in a considerable larger usage than other European countries. By a deregulation of the European electricity market the electricity price will level off between the countries, which will cause a higher electricity price in Sweden than we are use to. To prevent that the Swedish industry don?t lose competitiveness against the other European countries, it will require energy efficiency activities in all different forms.ABB Sweden has decided to decrease their total energy usage with five percent in two years.
Passivhus, detaljutformning och dess köldbryggor
Along with rising energy prices and increasing awareness of environmental issues, the criteria for buildings energy performance have been sharpened through the years. Today, ?passive house? and ?low energy house? are commonly used phrases in the construction industry and is expected to become increasingly common in the future.For houses with well-insulated building envelope the importance of well constructed details increases when minimizing the heat losses. Examples of these details are floor-wall junction and window openings in the wall. In such connections thermal bridges occur, which means that heat more easily is transported out of the building, compared to the rest of the building envelope.This report deals with detail solutions around windows and a comparison between a traditional slab and a foundation from Koljern consisting of foam glass.