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383 Uppsatser om Electricity - Sida 10 av 26

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.

Framtidens driftcentral : En analys av den framtida driften av ett svenskt elna?t

Active work to increase the efficiency of energy use is taking place in Sweden and throughout all of Europe. Electricity is an important part in our society?s energy system which means that the electrical grid operators and associated therewith has a central role in this work. Monitoring and controlling the electrical grids are managed from the distribution system operator?s DC, dispatch center.The aim of this report is to examine how the operations in a typical DC on the Swedish Electricity distribution network will look like in five to ten years.

Ungdomars läsvanor och hur vi skulle kunna inspirera ungdomar att läsa mer skönlitteratur

AbstractThe purpose of this work is to try to find out how young people's reading habits among students look at different types of secondary school, ie. both theoretical and practical, and what factors might encourage them to read more. My questions have been; do young people read today? Is there any difference between city, gender or program? What can a teacher do to inspire young people to read more? I have made a questionnaire survey among different students at two different high schools in Skaraborg. The first school is a high school located in a medium sized town, where I made inquiries to the scientific program, social program, Business and Administration Program and the Electricity Program.

Faktorer som påverkar vindkraftsutbyggnaden

Wind power is expanding rapidly in Sweden. Increasing amounts of wind power sets higher requirements on balancing power and grid expansions and would affect the whole Swedish Electricity system. The aim of this report is to examine the factors affecting the wind power expansion in Sweden. How many wind power plants projects will obtain building permissions and what costs and revenues can be expected? How much balancing power will be required and does a changing geographical distribution of the wind power plants reduce the need of balancing power?A survey of the county board?s official applications has been made and out of all the applications, corresponding to 80 TWh produced per year, about half of the applications are expected to obtain a permit with a major portion of them located in the north of Sweden.Especially older wind power plants, deriving revenue from Nord pool, find themselves today in a complicated financial situation.

Alternativa drivmedel i den svenska vägtrafiken år 2030 : En utvärdering av den svenska regeringens målbilder

The Swedish government has set up the overall goal that no net emissions of greenhouse gases can occur after 2050. A sub-target has been developed for road transports which states that the use of fossil fuels must be reduced with 80% to 2030 in order to be completely abolished to 2050. A public inquiry mapping how this can be achieved was handed in to the government late in 2013. The use of alternative fuels for road transport, both biofuels and Electricity, is expected to give the biggest contribution to the reduction of the use of fossil fuels. The inquiry sets up a number of goals for how much the use of alternative fuels must increase to 2030 in order to reach the overall goal and which instruments that are needed in order to do so.The aim of this thesis is to evaluate how these goals can be reached and what the most likely obstacles that may hinder the reaching of these goals may be.

Småskalig elproduktion i Arvika

Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where Electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of Electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.

Solel och solvärme ur LCC-perspektiv för ett passiv-flerbostadshus

This master?s degree project concerns the combination of a multi dwelling passive house with solar energy for the generation of Electricity and domestic hot water (DHW). Different alternatives with either solar thermal systems or photovoltaic (PV) systems are compared with two reference alternatives producing DHW from Electricity or district heating. The economical comparison uses a life cycle cost (LCC) perspective based on the present value of expenditures for investment, energy and annual operating and maintenance.The energy yields from the solar energy systems were calculated by hand and with simulation software. Calculation and dimensioning of PV systems were carried out with a software called PVSYST.

Elektromagnetisk och mekanisk design av en 20MW turbogenerator

At the Division of Electricity at UppsalaUniversitythere are ongoing researches, including a research concerning turbo generators.Turbo generators produce a large share of Electricity in the world; however they are costly mainly due to the fact that the cooling and ventilation that are needed to eliminate the excess heat from the generators are expensive. Turbo generators work with high efficiency and in this project, the main task is to simulate a generator while taking into account that the generator must be designed against self-oscillation, centrifugal force, exhaustion and heat. The turbo generator must be simulated without being too expensive and complicated.In this project, the dimensions of the turbo generator depend on the efficiency of it, and where the losses are in the generator. Furthermore, the optimum values need to be chosen with the help of the ACE simulation program. The report begins with an introduction describing the project followed by a task description that is dealing with the project.

Kompostering av organiskt avfall från Gästrikeregionen ? miljöpåverkan av olika behandlingsalternativ

In the coming years, organic food waste will be collected in the region of Gästrikland, Sweden. The collection is planned to cover the entire region by the end of year 2007. To start with, smaller amounts are being collected and transported to a central composting plant in Sala. However, a central composting plant in the region of Gästrikland is projected.The objective of this thesis is to evaluate a number of possible methods for composting of organic food wastes regarding their environmental impacts and localization.There are four scenarios for future composting of organic waste that have been evaluated. There are two that consist of membrane composting, either in Sala or in the region of Gästrikland.

Vidareutveckling av PV/T-receiver för koncentrerat solljus

The rising demand for Electricity and heat raises a big challange for the society and engineers. Many products have been introduced to the market to supply more energy to the energy systems. Absolicon AB is a Swedish company that develops and markets a combined heat and power generating product. The product, Absolicon X10, uses a parabolic trough to concentrate the radiation of the sun onto a receiver. The receiveris equipped with mono crystalline solar cells and is cooled by a circulating liquid media.

Opportunities for improved environmental sustainability of a wine producer in South Africa : natural resource management and climate change adaptation and mitigation

South Africa has been among the top ten wine producing countries for at least 20 years. Even though the land under grapevines is decreasing globally it is still increasing in Africa. The awareness of environment has strengthen the last years and South African producers experience a high demand of environmentally friendly produced wine, especially from the European market. This demand was the driving force behind the development of the world unique sustainability certification, Integrated Production of Wine (IPW), which is inscribed in the South African legislation. What makes this certification unique is that consumers can trace their product all the way back to the farming practices owing to the identity number specified on the IPW Integrity & Sustainability seal on certified products.

Solvärme på Utö

The guest harbor on Utö, Utö Gästhamn, is currently using Electricity for heating all of the water used in the showers and taps. Because of the large amount of visitors, especially during the summer months, the hot water usage gets very high and that is also the case for the electrical bills. During the year of 2011 the cost of Electricity for Utö Gästhamn reached a total of 257 500 kr. Out of these 257 500 kr approximately 142 000 kr, 55 % of the total cost, were because of the water heating.The report is the result of a cooperation with Skärgårdsstiftelsen, the Green Islands-project and Utö Gästhamn where the mutual goal is to dimension a solar energy system, to promote the sustainable development.Initially the different techniques for the solar energy system are researched. The techniques are plane solar collectors, evacuated tube collectors, pool collectors and photovoltaic cells.

EN FALLSTUDIE OM URBAN VINDKRAFT VID ALBANO

The use of energy is an important question in today´s society, and a substantial part of the energy that is used today is used in our homes. To lower this usage is vital, and there are regulations in place both on the national and the local level, that say that new apartment blocks must be built to consume less energy, which in the end will lower the impact on the climate.One way to make the housing sector more environmentally sustainable, is to produce energy issions that are bad for the environment, for example to build wind turbines close to or even on the buildings, so called urban wind power. The scope for this report is to see if urban wind power could be a sustainable alternative for the residential area that Svenska Bostäder plans to build in Albano in Stockholm.There are extensive scientific theories regarding wind and wind power, and a literature study is made to investigate past knowledge in the area. Efforts have been made to find earlier trials with urban wind power and, both scientific research and trials where urban wind power actually has been installed. The theory chapter deals both with the wind itself and how Electricity can be generated from wind.

Energieffektivisering och solenergi i en universitetsbyggnad : Undervisningshuset och Biblioteket i Uppsala

Akademiska hus is a real estate company that specializes in providing Swedish universities with housing facilities for educational and research purposes. The company strives to reduce its use of energy by 40% between the years 2000 and 2025. The aim of this thesis is to determine which measures can be taken to reduce the need of purchased energy in a building that is used by theSwedishUniversityof Agricultural Sciences inUppsala.In order to determine the results of various changes to the building envelope and ventilation system, the building was modelled in the computer simulation program VIP-Energy. Other proposed changes to make the use of energy more efficient concerned water use and lighting. The need of purchased energy can also be reduced by producing Electricity or heat on site, using solar energy.Results show that economically viable measures include upgrading windows and faucets, adjusting control systems for ventilation and lighting, and installing roof mounted solar panels for power production.

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..

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