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669 Uppsatser om Electricity grid - Sida 4 av 45
Solceller pa? Uppsalahems fastigheter : Ekonomisk potential fram till 2030
Uppsalahem is the leading housing corporation in Uppsala with its over 160 real estate properties. Uppsalahem is owned by the municipality of Uppsala, which has a climate and energy goal that aims for 100 MW of solar energy to be installed in Uppsala by 2030. The 100 MW goal, combined with Uppsalahem?s environmental policy, is a strong incentive to investigate the possibility of installing PV modules on the many available roof areas that Uppsalahem possesses. The objective of this thesis is to create a foundation for future decisions regarding PV systems for Uppsalahem.
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..
Utvärdering av konsekvenserna för nätanslutning av vindkraftparker i Sverige vid införandet av nätkoden Requirements for Generators
Grid codes are becoming more demanding on power generating units due to the factthat the complexity of the power grid is increasing. The penetration of wind powerhas grown over the last years and it is clear that wind farms need to be addressedwith the same type of grid codes as conventional generation units. There is howeveran undeniable difference between the technology in conventional synchronousgeneration units, and the asynchronous generation units in wind farms.This thesis has reviewed the current grid code in Sweden and compared it to the newcode proposed by ENTSO-E, ?the Requirements for Generators?, in the aspect ofwind farms with an installed power of 30 MW or more. The comparison has beencomplemented by an analysis of how wind farms of two different technologies(Doubly fed induction generators and full power converters) can meet therequirements and technical proposals have been given on how to be able to meetcompliance with the new grid codes.The Requirements for Generators contains many non-exhaustive and optionalrequirements, because of this it has been difficult to, at this stage, exactly point outthe technical impact on the grid connection of future wind farms in Sweden.
ELCERTIFIKAT - En diskussion kring de svenska elcertifikatens rättsliga natur, ekonomiska värde samt möjlighet att ta i anspråk vid en utmätning -
1st of may 2003, a new energy system based on electricity certificates, was initiated in Sweden. The purpose with this system, is to stimulate an enlargement of energy production from renewable sources. The electricity system, ist built on that the producers of energy from renewable sources confer a electricity certificate from the government for every produced MW energy from renewable sources. The electricity certificate is supposed to be turned over and with that generate reciepts to the producers. Furthermore there is an obligation for the energyusers und energysuppliers, that means that the users and the suppliers every year the 1st of april got to have electricity certificates in proportion to their energy consumption during previous year.
Energieffektivisering i flerbostadshus för studentboende
Uppsalahem AB is a municipally owned real estate concern that owns and administrates housing for nearly 30 000 people. The company puts a lot of effort into reducing the energy use of their housing stock. This project is a master?s thesis in the energy systems programme at Uppsala University, carried out in collaboration with Uppsalahem. The aim of this thesis is to provide energy saving measures for fourteen student housing buildings in Uppsala, Sweden.
Kartläggning och utvärdering av produkter och tjänster kopplat till begreppet Smart Grids
The Smart Grids development is driven by forces concerning safe electrictransmission done in an energy efficient way. Vattenfall Eldistribution AB has a visionto transform their electricity network into Smart Grids. To invest in Smart Grids theyhave a need to show their customers what advantages they will get from thedevelopment. This led to the formulation of this dissertation project where the aim isto identify products and services related to Smart Grids that will increase thecustomer satisfaction for Vattenfall Eldistributions private customers.The project started with a mapping of existing products and services on the Swedishelectricity market. From the mapping several development possibilities for VattenfallEldistribution were identified.
Matematisk kod i grafisk design
Målet har varit att undersöka hur grafiska formgivare kan använda sig av matematisk kod i form av fraktala system för att skapa inspirerande grid. Genom att titta på befintliga fraktala mönster och sedan anpassa vissa av dem till gridsystem skapades under designprocessen ett antal olika fraktala grid. Hur väl dessa gridsystem fungerade testades i en skisskalender - en fickkalender för formgivare med plats att skissa. För att kontrollera och verifiera de resultat som kom fram under designprocesssen jämfördes de med åsikter från en fokusgrupp bestående av grafiska formgivare. Slutsatsen blev att fraktala gridsystem inspirerar grafiska formgivare att skapa dynamiska och harmoniska layouter.
Numerisk modell för global transport av spårämnen i atmosfären
The aim of this project was to develop a numerical model simulating the global transport of air pollution. The model currently used by SMHI, the Swedish Meteorological and Hydrological Institute, was intended to perform such simulations at regional scales. However, the usage of a grid based on longitudes and latitudes makes this model work poorly in global simulations. The problem with this grid is that the nodes are concentrated near the North and South Poles. Due to this characteristic, the Courant, Friedrich and Lewy-condition for numerical stability puts a sharp bound on the timestep length.
Trafikverkets effektstyrningssystem - EFS 132 kV : Bidraget till minskade förluster
The technological legacy from the early electrification of the Swedish railroads has resulted in a power grid with a lower grid frequency than the national power grid from which it is fed. Energy transfer between these power grids with different frequencies requires substations, adapting the grid frequency for the rail road power grid. For this purpose, a feeding power grid has been built, stretching across the country from Boden in the north to Tälle/Häggvik in the south.Power transfer in the Swedish power grid results in voltage angle differences which increase with increasing loads and transfer distance. These voltage angle differences are transferred from the power feeding substations to the rail road power grid, will in some extent cause loss of energy due to unwanted power flows from north to south.To minimize the losses due to this phenomenon, a power management system called EFS 132 kV has been developed and implemented. The system minimizes the unwanted power flows and controls the desired power flow for a good distribution of loads between the power feeding substations.This thesis investigates the extent of the transmission losses avoided due to the EFS 132 kV that coordinates the idling angles to a common reference point.The results indicate that EFS 132 kV affects the power flow, especially between the northern substations through an improved load distribution.
Elektrifiering av jordbruksmaskin : Direktkoppling till solföljare och elnät
The agricultural sector is currently highly dependent on fossil fuels, with diesel beingmost prominent. There are however both historical and modern alternatives thathave not been subject to enough evaluation to disregard them as suitable alternative.This report aims to theoretically investigate the feasibility of converting aconventional diesel driven tractor to run on electricity, delivered via a cableconnected to either the main power grid or on-site electric production, such asphotovoltaic. Delivering electricity to the machine via a cable is a method withhistorical roots in the early 20th century and in the present day mining industry.The economic and technological potential of the technique are evaluated, along withthe examination of several different motor powers, voltages, losses and constructionideas. The report finds the technique to be both possible as well as long termeconomically and environmentally beneficial. To realise this method however, somedeviations from the present methods of agricultural farming must be made,considering the more advanced driving patterns, the limited mobility and therequirement for extra driver awareness.
Undersökning av solcellspotentialen för golfverksamheter i Sverige
Photovoltaic Systems in Sweden has longbeen heavily dependent on subsidies and grants to bring in a profit for the investor. Production of excess electricity is a major reason for this as the compensation for excess electricity today is low. However, there are businesses that have an electricityneed that are particularly suitable for solar electricity. These businesses have an electricity demand when the sun shines the brightest and if the Photovoltaic System is properly scaled, the excess electricity can be minimized. A golf club is that kind of a business and this thesis aims to examinate the solar power potential for golf businesses in Sweden.Nine golf clubs was selected from different locations in Sweden.
Underlag till energieffektiviserande åtgärder i nätstationer
Umeå Energi are working towards a goal, that in the year of 2018, they will be completely climate neutral. As a part of this, one target is to reduce their grid losses by 4 % of the 2012 level, which corresponds to an overall reduction of the grid losses of just over 1.7 GWh. In many residential areas, the distribution grid is designed and rated for electric heating as the heating in the houses. As many of the houses later has been converted to other types of heating, their electricity use has decreased and the total power output from many of the secondary substations has decreased significantly. Because of this, many of these stations today are well oversized, which in turn means that the energy losses in these stations are unnecessarily high.In this degree project, 25 secondary substations have been studied, all located in residential areas in and around central Umeå.
Effektivare elanvändning på avfallskraftvärmeverk : Förslag till handlingsplan för minskad elanvändning på Renovas anläggning i Göteborg
This thesis has identified and studied measures to allow for reduced use of electricity in a waste incineration plant in western Sweden. The energy extracted from the waste at the powerplant is utilized and sold in form of electricity and heat. Technical and environmentally the combined heat and power plant is by today's standards among the leading waste incineration plants in the world. The owners are constantly striving to improve the efficiency of the waste incineration plant. They have seen the opportunities for savings in reducing internal usage of electricity.
Lönsamhetsanalys av tekniker för utökad elproduktion i kraftvärme : Med hänsyn till elprisets variationer
This thesis aims to examine the viability of various techniques for increased electricity generation in CHP plants and the effect of electricity price fluctuations on the profitability.The techniques examined are fuel dryer, pellet production, methane production, combined methane- and pellet production, seasonal heating storages in caverns and pit heat storages and condensing tail. Using Excel and Matlab, the prerequisites for investment costs, revenues and expenses were calculated.What affects the price of electricity is a combination of economic and technological development, energy prices, economic structure, population changes and weather. Different scenarios for the electricity price were therefore examined. In the base case, the electricity price was given by the Nord Pool electricity price statistics of area three in 2011. Thereafter, WiMo was used to design the electricity scenarios for 2030, which was then applied to the data to obtain the viability of various scenarios. The techniques examined were found to give greater profits to the CHP plant by increasing and optimizing the production of electricity.
Undersökning av elkvalitet i distributionsnät med omfattande vindkraftselproduktion
The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.