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4212 Uppsatser om Energy Systems - Sida 14 av 281

Samverkande, motverkande eller kompletterande? : En uppsats om relationer mellan styrsystem

Title: Co-operative, prevent or complement? - An essay on the relationships between control systems. Authors: Kim Eriksson and Victoria KarlssonPurpose: The essay aims to describe the relations between control systems and how they related to each other, based on an operationalization of the control systems. Research question: What are the control systems relations to each other? With regards whether control systems co-operative, prevents and/or complement each other.Theoretical framework: The essays theoretical framework is based on Malmi and Browns (2008) description of five different control systems and control mechanisms associated with each control system.   Research methodology: The method was based on three different data collection methods. These methods were observations, documentation, and semi-structured interviews.Conclusions: It is concluded that the control systems has comprehensive relations. Control systems have more, than one, relation to each other..

Traditionell ekologisk kunskap i en framtid med lokala, självförsörjande och urbana samhällen

Several scenarios point toward a future where we are far more people on Earth than today, where most of those people will live in cities and where oil no longer dominates in the transport systems and in agriculture as an energy source and where less energy will be available to us. The report investigates what areas in traditional ecological knowledge that can contribute to the transition that follows a future with less energy and establishes three areas with the potential of becoming important: areaspecific biological knowledge in societies that are more dependent upon its surrounding environment and its natural prerequisitesthe local management of these biological resources, which often means a fair sharing and sustainable handling of the resources and which has been observed in Nobel price awarded Elinor Ostrom?s researchthe world views that lie behind how the environment is considered and managed, world views that can inspire and point toward how we in the future should formulate world views that do not give the destructive modern management of the environment It is also noted that the magnitude of the city living in the future is a historical news and that very little research has been done in how traditional knowledge can be transferred into this kind of living..

Utredning av fastighetsel i ett äldre och ett ombyggt flerbostadshus i Gävle

The residential and service sector in Sweden accounts for approximately 38% of the total energy usage and Sweden has an aim to reduce the total energy use by 20% by 2020 compared to 2008, which means residential sector will have to improve energy efficiency. As part of that a law was instituted by the Swedish parliament that all properties must have an Energy Performance Certificate (EPC) to thereby give the property owners a greater insight into energy use in their buildings and propose recommendations for energy-efficiency measures. On the EPC, a value on the building's energy performance in terms of energy use in kWh / m2 per year is declared, of which electricity is a share of it. Instructions on what to include in the amount facility electricity for running the facilities is regulated by the authority for building, Boverket while SVEBY has made an interpretation of the regulations in their report "Brukarindata bostäder" where they have a table on what should be included in the amount and what not to include.This report is a study of two similar apartment buildings, where one of the buildings recently underwent renovation, to see if the declared amount of energy for electricity, in the EPC, is consistent with the measured value, and whether there has been any reduction in facility electricity in the renovated building after the renovation.The result shows that the measured value of the building electricity was 2.6 kWh / m2 per year, 28,8 %, lower than the declared value in the building that have not undergone a renovation. Calculation of values from previous years (2011) by the same percentage of facility electricity as in the results of the measurements, 56.7%, it becomes clear that the declared value for facility electricity in the EPC of the renovated building do not correspond with reality and that there has been an increase in use of facility electricity after the renovation..

Miljö eller avkastning? : en investeringsjämförelse mellan gammal och ny energi

The purpose with this study is to investigate funds that are environmentally friendly. Environment issues has become a large subject that affects all aspects in today?s society.  It is a global issue which has affected the awareness of environmentally friendly products and its benefits for the environment.How has this awareness affected the financial market?  In this study the authors have looked at six environmentally sound funds and six energy funds to answer the question if it´s better to have your money in traditional energy or in renewable energy.This study is made in an quantitative way, the data has been gathered from the internet database Morningstar. The energy funds have had its biggest assets in companies dealing with oil, and the environmentally sound funds have had its biggest assets in renewable energy. Bye looking at the different funds rate of return and relating that to risk managing theories of Sharpe and Treynor, the authors compared the two types of funds.During the period that was looked at during this study ( third quarter of 2007 until third quarter 2010) the energy funds outperformed the environmentally sound funds in every aspect. .

OSE och Linux : En studie om prestanda

There are some key elements which distinguish a general operating system, such as Linux, from a Real Time operating system, such as OSE. The later belongs to the category of soft Real Time systems while Linux is a general operating system, with significantly improved real time properties after version 2.6. These improvements make it interesting to compare the two systems.When comparing two operating systems, there are a number of issues which have to be considered. One way to measure the performance of the systems is by studying the time consumption for the same functionality and hardware.During the study, the items that appeared as the most important for the performance of the systems, were: process primitives, system primitives, interprocess communication, context switches and interrupt latency.This work demonstrates that it is possible and reasonable to do performance testing on two different operating systems. The implemented tests cover a number of basic functionalities, which appeared to be the most crucial ones for the performance of the systems..

Byggnadsintegrerade solcellssystem : Solceller som byggnadsmaterial

This thesis aims to identify the building integrated photovoltaic solutions available in the market with respect to general pros and cons of different systems and a technical description of there attachment system. Investigate and provide examples of various building integrated photovoltaic solutions in Sweden and describe the experiences and results of these projects.The methods used to obtain relevant information are interviews with individuals involved in significant projects and a thorough search of different solutions from solar suppliers.The conclusion is that solar energy is needed for a sustainable society. There are endless opportunities regarding BIPV, with many companies with different products and individual solutions. But so far it?s not so customary in Sweden.

Energisparläge i automationsindustrin : Potential för att minska tomgångsförluster med industriella styrsystem

Former studies have shown that a considerable part of industries? energy usage can stem from idle times in the production. This thesis, carried out at Siemens Industry sector, evaluates the potential for using the control system to automatically put machines into energy saving mode during idle times. The main part of the thesis consists of a case study performed on machine tools at a Scania production site in Södertälje. Through load measurements the potential for energy savings was determined.The results show that there is a great potential for energy savings during idle times at the site.

Effektiviseringsåtgärder i tryckluftsystemet hos Vattenfall Värme Uppsala

In this work an assessment of the compressed air system in the facilities of Vattenfall Heat Uppsala has been conducted. The facilities constitutes, among others, a combined heat and power plant, and two waste incineration plants. The compressed air is supplied primarily by seven rotary screw compressors and yearly electric energy consumption in these has been determined. Furthermore, the usage of compressed air has been mapped in order to find processes with energy savings potential. Several suggestions how to reduce the usage of compressed air have been presented, resulting in decreased need of electric energy and reduced CO2-emissions.The results show that total need of electric energy in the compressors, during a standard production year, amounts to 5.83 GWh.

Solvärme för en skola i Lerum. Studier av olika systemalternativ.

Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.

Energieffektiv byggnad i stadsmiljö

This report will present an energy efficient building in the centre of Kalmar city. It willbecome energy efficient because of the worldwide goal to reduce our energy using in ourbuildings.The values of architecture have been given a great part in this report. The building is supposed to be placed in Kvarnholmen in a unique environment in centre of Kalmar city.Because of the placement it is very important to show respect to the surroundings and the history of Kalmar..

Har energidryck någon kognitiv effekt i kombination med alkohol? : Med fokus på komponeneten koffein

Background: Energy drinks have been found in everyday-stores since 1997 and their popularity have increased over time. Consumtion of energy drinks takes place because of their ability to increase concentration and to decrease fatigue but also because of the popularity the drinks have got. Target groups for these stimulating beverages are adolescents and young adults. Energy drinks contain caffeine, taurine, glucuronolacton, carbohydrates and B-vitamins and voices have been raised about the eligibility for young people to ingest large quantities of these kinds of substances. Because of the properties of these substances it has become popular to mix energy drinks and alcoholic beverages to make up for the negative effects of alcohol and to be able to drink larger quantaties.Aim: The aim of this literature work was to investigate cognitive effects of the combination of caffeine in terms of energy drinks and alcohol and to determine if these effects could be harmful.Method: This literature work is based on five scientific articles retrieved from PubMed.

Förnybar energi ur ett kvinnligt och manligt perspektiv : En attitydundersökning med avseende på att kartlägga hur synen på fönybar energi påverkas av om individen är kvinna eller man

Abstract The extraction and usage of energy give rise to immense environmental problems which helps to accelerate climate change. Energy is an important resource for the community and there are a variety of different types of energy sources available, that are either classified as renewable or non-renewable energy sources. The usage of renewable energy sources cause less environmental impact than the usage of non-renewable energy, which in turn means that the energy?s strain on the environment is strongly affected by the type of energy source used.The aim of the study is to describe to what extent attitudes towards renewable energy are affected by whether the individual is male or female, by examining the hypothesis regarding how women have a closer connection to nature and to a larger extent shows on an pro-environmentally friendly behavior than men, and if it also can be detected on issues related to renewable energy and thus imply that women have a friendlier approach towards renewable energy than men. A number of ecofeminist believe that women have a stronger bond with the nature through her embodiment as a woman and by her maternal role, which according to previous research also leads to the fact that women shows on a more extensive environmental behavior.Through a qualitative research method in the form of semi-structured interviews has three female and three male respondents been asked questions with regards to the environment, individual responsibility and energy.

HÅLLBART BYGGANDEMED HJÄLP AV BIM : Effektiva energianalyser och LCC

The society strives for sustainable development, in the construction industry it is expressed through sustainable building. Energy and LCC analyzes increases the ability to make conscious decisions in the process. A problem in the construction industry is that energy and LCC analysis is not used to the desired extent, as they are perceived as complicated and time consuming. The report aims to achieve a more sustainable building through increased use of energy and LCC analyzes.The goal is to show how BIM can be used to improve the efficiency of the energy and LCC analyzes.The study was conducted with a literature review and a case study to answer which information that is required in a BIM model to perform energy and LCC analyzes. The study also shows which software can be used in BIM based energy and LCC analyzes and how the analyzes can be carried out efficiently.The result shows that effective analyzes may be performed if the BIM-model contains the relevant information for making analyzes.

Prefabricerade passivhusväggar

Background: The most energy efficient houses today are so called passive houses. These houses achieve high energy-efficiency partly by having well insulated walls. U-value describes the amount of heat transfered through a building element, the more insulation, the smaller U-value. A typical passive house wall have a U-value of 0.10 W/m2,°C. The passive houses are primarily made as small family houses and not as a block of apartments.

Optimering av B-stolpe

Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.

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