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Utvärdering av solcellsanläggningar i Västerås : Jämförelse av verkligt systemutbyte mot teoretisk simuleradSundqvist, Tobias, Rahimi, Elias January 2018 (has links)
Solar cells is one of the cleanest and most environmentally friendly ways to produce electricity. Västerås city has invested in a number of solar systems in public buildings as a step to solve the energy issues of the future and contribute to a sustainable environment. The purpose of this project is to compare the real system yield from Västerås city´s solar plants with simulations. Produces the solar plants as expected or not, and if not, what might be the cause. Data were collected about the solar cell installations, by Mälarenergi Elnät and Västerås city. The real system yield was calculated and then the solar plants were simulated in PVGIS (Photovoltaic Geographical Information System) to obtain the theoretical yield. This project shows that most of Västerås city´s solar plants have a yield that is as expected according to the simulations or higher. However, there are some solar plants with a low or very low yield compared to the simulations. The yield varies considerably during the year. For those plants where the yield has been studied monthly, the real yield is higher in the second half of the year compared with the first half. The self-consumption varies greatly between the different solar plants, but generally it is high. Some solar plants have a very high self-consumption of 100 % and some have a very low of 30-40 %. Some solar plants have a higher yield than expected and it may depends to the fact that the installed power is a few percent higher than what the manufacturer states. The simulations might be unsure, because losses, solar radiation and weather may vary. The solar plants that have a low yield compared to the simulations may have a broken or disconnected component, shading and dirt may also affect. To have as high self-consumption as possible is an economically advantage, as long as the plant is not under-dimensioned because the goal is to produce electricity. There is no clear pattern showing which of the four PVGIS simulations is best matched to reality.
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[en] MIMO MEASURED CHANNELS: CAPACITY RESULTS AND ANALYSIS OF CHANNEL PARAMETERS / [pt] MEDIDAS DO CANAL MIMO INDOOR: ANÁLISE DA CAPACIDADE E DOS PARÂMETROS DO CANALROBSON DOMINGOS VIEIRA 21 March 2006 (has links)
[pt] Sistemas com múltiplas antenas transmissoras e receptoras,
também conhecidos
como sistemas MIMO (Multiple Input-Multiple Output), têm
sido apontados como
uma solução para aumentar a capacidade de enlaces sem fio,
permitindo aos usuários
utilizar aplicações com altas taxas de dados. Isto é
extremamente importante em
sistemas onde a capacidade obtida com as técnicas
tradicionais é bastante limitada
devido às características do ambiente de propagação. Com o
sistema MIMO, algumas
destas características são exploradas para criar canais
paralelos e obter aumento
expressivo de capacidade. A análise da capacidade de
sistemas MIMO se baseia em
uma modelagem desenvolvida a partir do comportamento
estatístico dos pares de
enlaces existentes entre as múltiplas antenas
transmissoras e receptoras. Existe,
portanto, um grande interesse em medir este comportamento
para situações típicas
bem como em relacioná-lo a determinados parâmetros do
sistema. Nesta tese
apresentam-se os resultados de uma campanha de medidas
visando caracterizar canais
MIMO de faixa estreita e faixa larga em ambientes fechados
(indoor) com uma
freqüência de portadora de 2GHz. A partir dos dados
medidos, avalia-se a capacidade
e diversos parâmetros do canal espaço-temporal. Os
parâmetros do canal MIMO são
estimados através do algoritmo FD-SAGE e as dispersões
temporal e espacial do
canal são calculadas a partir dos parâmetros estimados.
Uma análise dos autovalores
da matriz do canal MIMO é realizada com o objetivo de
relacionar os valores da
capacidade ao número de canais paralelos. É analisada,
ainda, a correlação entre a
capacidade e os parâmetros físicos do canal, tais como
espaçamento entre os
elementos do arranjo, espalhamento angular, espalhamento
dos retardos, número e
potência dos multipercursos. / [en] Multiple antenna systems known as MIMO (Multiple Input
Multiple Output)
systems have been proposed as an effective way to address
the user demand for high
data rate applications in wireless systems. This is
especially important in systems
where the capacity attained with traditional techniques is
very limited due to the
adverse characteristics of the propagation environment.
With MIMO, some of these
characteristics are used to create parallel channels
producing significant increase in
capacity. The analysis of MIMO capacity is based on models
developed from the
statistical behavior of the multiple links between the
transmitting and receiving
antennas, and therefore there has been large interest in
measuring these characteristics
in typical scenarios and in relating the data to system
parameters. In this thesis the
results of a MIMO wideband measurement campaign carried
out in an indoor
scenario with a carrier frequency of 2 GHz is presented.
The wideband and
narrowband channel capacity and several channel parameters
are evaluated from the
measured data. The channel parameters are estimated using
the frequency domain
Space-Alternating Generalized Expectation maximization (FD-
SAGE) algorithm.
Temporal and spatial dispersions of the multipath channel
are calculated from the
estimated parameters and an eigenvalue analysis is
performed seeking to relate the
capacity values to the number of parallel channels. In
addition, the correlation
between channel capacity and physical parameters as
antenna spacing, angle spread,
delay spread, number and power of multipath components is
investigated.
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Dimensionamento de um sistema fotovoltaico conectado à rede a partir das características de inclinação e orientação dos módulos fotovoltaicos / Design of a grid-connected photovoltaic system from the photovoltaic modules tilt and azimuth angles characteristicsPaiva, Gabriel Mendonça de 03 June 2016 (has links)
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Previous issue date: 2016-06-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aimed to evaluate the design of a grid-connected photovoltaic (PV) system
according to the positioning of the modules which compose the generator depending on tilt
and azimuth angles in Goiânia, Goiás. In that purpose, a review of the literature was carried
out concerning the main methods of inverter sizing ratio analysis applied to grid-connected
PV systems. Starting from an hourly average climate measurement database from Goiania, an
algorithm was developed to search for the ideal local inverter sizing ratio, considering the
use of polycrystalline module technology. The parameters used in the analysis were provided
by the manufacturers of the componentes used in the grid-connected PV system in installation
at the Electrical, Mechanical and Computational Engineering School (EMC) from Federal
University of Goias (UFG), which nominal power is 33.84 kWp. An inverter sizing ratio band
of 0.54 to 0.77 was obtained for a -90° to +90° azimuth angle variation and 0° to 90° tilt
angle variation. The potential of financial indicators improvement was verified and it was
estimated a potential reduction in the levelized cost of energy above 10% comparing the
inverter sizing ratio improved system to an unitary inverter sizing ratio system. / Este estudo tem como objetivo avaliar o dimensionamento de um sistema fotovoltaico
conectado à rede (SFCR) de acordo com o posicionamento dos módulos que compõem o
gerador quanto ao ângulo de inclinação e ao ângulo azimutal em Goiânia, Goiás. Para isso foi
realizada uma revisão da literatura quanto às principais metodologias de análise do fator de
dimensionamento do inversor (FDI) aplicado a SFCRs. A partir de uma base de dados em
intervalos horários de medições climáticas de Goiânia desenvolveu-se um algoritmo para
busca do FDI ideal para a localidade, considerando o uso de módulos de silício policristalino
(p-Si). Os parâmetros utilizados na análise foram os parâmetros fornecidos pelos fabricantes
dos componentes utilizados no SFCR em instalação da Escola de Engenharia Elétrica,
Mecânica e de Computação (EMC) da Universidade Federal de Goiás (UFG), cuja potência
nominal é de 33,84 kWp. Os métodos de análise do FDI foram comparados e foi considerado
mais adequado neste estudo o método das perdas máximas anuais por limitação de potência
no inversor. A faixa de FDI obtida para uma variação de -90° a +90° no ângulo azimutal e de
0° a 90° no ângulo de inclinação foi da ordem de 0,54 a 0,77. O potencial de aprimoramento
de indicadores financeiros por meio do FDI foi verificado e foi estimada uma potencial
redução acima de 10% do custo da energia produzida comparando o aperfeiçoamento do FDI
com um FDI unitário.
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Multisensor Microwave Remote Sensing in the CryosphereRemund, Quinn P. 14 May 2003 (has links) (PDF)
Because the earth's cryosphere influences global weather patterns and climate, the scientific community has had great interest in monitoring this important region. Microwave remote sensing has proven to be a useful tool in estimating sea and glacial ice surface characteristics with both scatterometers and radiometers exhibiting high sensitivity to important ice properties. This dissertation presents an array of studies focused on extracting key surface features from multisensor microwave data sets. First, several enhanced resolution image reconstruction issues are addressed. Among these are the optimization of the scatterometer image reconstruction (SIR) algorithm for NASA scatterometer (NSCAT) data, an analysis of Ku-band azimuthal modulation in Antarctica, and inter-sensor European Remote Sensing Satellite (ERS) calibration. Next, various methods for the removal of atmospheric distortions in image reconstruction of passive radiometer observations are considered. An automated algorithm is proposed which determines the spatial extent of sea ice in the Arctic and Antarctic regions from NSCAT data. A multisensor iterative sea ice statistical classification method which adapts to the temporally varying signatures of ice types is developed. The sea ice extent and classification algorithms are adopted for current SeaWinds scatterometer data sets. Finally, the automated inversion of large-scale forward electromagnetic scattering of models is considered and used to study the temporal evolution of the scattering properties of polar sea ice.
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Investigation, Design and Implementation of MIMO Antennas for Mobile Phones. Simulation and Measurement of MIMO Antennas for Mobile Handsets and Investigations of Channel Capacity of the Radiating Elements Using Spatial and Polarisation Diversity Strategies.Usman, Muhammad January 2009 (has links)
The objectives of this work were to investigate, design and implement Multiple-Input Multiple-Output (MIMO) antenna arrays for mobile phones. Several MIMO antennas were developed and tested over various wireless-communication frequency bands. The radiation performance and channel capacity of these antennas were computed and measured: the results are discussed in the context of the frequency bands of interest.
A comprehensive study of MIMO antenna configurations such as 2 × 1, 3 × 1, 2 × 2 and 3 × 3, using polarisation diversity as proposed for future mobile handsets, is presented. The channel capacity is investigated and discussed, as applying to Rayleigh fading channels with different power spectrum distributions with respect to azimuth and zenith angles. The channel capacity of 2 × 2 and 3 × 3 MIMO systems using spatial polarisation diversity is presented for different antenna designs. The presented results show that the maximum channel capacity for an antenna contained within a small volume can be reached with careful selection of the orthogonal spatial fields. The results are also compared against planar array MIMO antenna systems, in which the antenna size considered was much larger.
A 50% antenna size reduction method is explored by applying magnetic wall concept on the symmetry reference of the antenna structure. Using this method, a triple dual-band inverted-F antenna system is presented and considered for MIMO application. Means of achieving minimum coupling between the three antennas are investigated over the 2.45 GHz and 5.2 GHz bands.
A new 2 2 MIMO dual-band balanced antenna handset, intended to minimise the coupling with the handset and human body was proposed, developed and tested. The antenna coupling with the handset and human hand is reported in terms the radiation performance and the available channel capacity.
In addition, a dual-polarisation dipole antenna is proposed, intended for use as one of three collocated orthogonal antennas in a polarisation-diversity MIMO communication system. The antenna actually consists of two overlaid electric and magnetic dipoles, such that their radiation patterns are nominally identical but they are cross-polarised and hence only interact minimally.
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Λειτουργική και αισθητική εφαρμογή φωτοβολταϊκών / Functional and aesthetic application of photovoltaicsΣυγκρίδου, Δήμητρα 07 June 2013 (has links)
Τα φωτοβολταϊκά είναι κατάλληλες ενεργειακές συσκευές τόσο για εφαρμογή σε κεντρικές μονάδες παραγωγής ηλεκτρισμού (φωτοβολταϊκά πάρκα) όσο και σε ξεχωριστές μονάδες (κατοικίες και άλλα κτήρια). Και στις δύο αυτές περιπτώσεις, η εγκατάσταση των φωτοβολταϊκών επιδιώκεται να έχει την βέλτιστη κλίση και αζιμούθια γωνία των φβ πλαισίων, για να επιτυγχάνεται μεγιστοποίηση του παραγόμενου ηλεκτρισμού. Εκτός από τις περιπτώσεις που είναι εφικτή η βέλτιστη εγκατάσταση των φβ, υπάρχουν και περιπτώσεις που η εγκατάσταση παρουσιάζει ιδιαιτερότητα ως προς την τοποθέτηση και χρειάζεται ειδική μελέτη για την επίτευξη ικανοποιητικού αποτελέσματος. Στις περιπτώσεις αυτές και εκτός από το αυξημένο κόστος τα άλλα κριτήρια είναι κυρίως η επιλογή του κατάλληλου φβ πλαισίου και η λειτουργική και αισθητική ιδιαιτερότητα της εγκατάστασης, σε συνδυασμό με τις ενεργειακές και περιβαλλοντικές προεκτάσεις.
Σκοπός της εργασίας αυτής είναι η μελέτη νέων τρόπων εγκατάστασης φωτοβολταϊκών, με την εξέταση των παραμέτρων που επηρεάζουν την ενεργειακή συμπεριφορά τους, ανάλογα του είδους και της τοποθέτησης των φβ πλαισίων, των συνθηκών θερμοκρασίας λειτουργίας, του πνέοντος ανέμου και φωτισμού και των ειδικών απαιτήσεων της εφαρμογής, στην κάλυψη των αναγκών σε ηλεκτρισμό. Ιδιαίτερη αναφορά γίνεται και στις συνέπειες από την ικανοποίηση αισθητικών απαιτήσεων των εγκαταστάσεων των φβ, επιδιώκοντας τον βέλτιστο συγκερασμό.
Στην εργασία μελετάται πειραματικά και σε συνθήκες φυσικού ηλιασμού η συνεισφορά των διάχυτων και κατοπτρικών ανακλαστήρων στην ενεργειακή απόδοση των φβ, η απαγωγή θερμότητας από τα φβ με νερό ή αέρα, η εγκατάσταση των φβ σε δυσμενή ενεργειακά κλίση και αζιμούθια γωνία, η χρήση διαπερατών στο φως φβ πλαισίων, κλπ. Δοκιμάστηκαν διάφορα φβ πλαίσια (πυριτίου, CIS, λεπτού φιλμ, οργανικά, άκαμπτα, εύκαμπτα, κλπ) και προτείνονται σχεδιάσεις φβ εγκαταστάσεων για ειδικές περιπτώσεις εφαρμογών. Επιπλέον, υπολογίστηκαν και τα περιβαλλοντικά οφέλη από την ευρεία χρήση των φωτοβολταϊκών, ανάλογα με τις ιδιαιτερότητες των εφαρμογών τους. / Photovoltaics are solar energy devices suitable for applications in both central power generation units (solar farms) and in separate units (residential and other buildings). In both cases, the aim is to install the photovoltaic modules with optimum tilt and azimuth angle, so that the electrical output is maximized. However, there are times where the photovoltaic modules cannot be placed with optimum angles and special considerations must be done in order to achieve a satisfactory result. In such cases, besides the increased cost, there are other things that need to be considered, such as the selection of a suitable type of photovoltaic module, the functional and aesthetic particularities of the installation in combination with the energy and environmental implications.
The aim of this thesis is to study new ways of installing photovoltaics, by examining the parameters that affect their energy behavior, depending on the type of pv module and the way they are installed, the operating temperature conditions, the wind, the lighting and the specific requirements of the installation, in order to meet the electrical needs. A particular reference is made at the consequences of satisfying the aesthetic requirements of pv installations, seeking the optimal solution between functional and aesthetic application.
In this thesis, experiments are conducted in natural conditions in order to determine the effects of the sunlight contribution of diffuse and specular reflectors at the energy efficiency of photovoltaics, the heat dissipation with water or air, the installation of pv modules with an unfavorable inclination and azimuth angle, the use of transparent pv modules, etc. Furthermore, several types of pv modules are tested (silicon, CIS, thin film, organic, rigid, flexible, etc.) and suggestions are made for special applications. In addition, an estimation of the environmental benefits of the widespread use of photovoltaics is done, according to the particularities of their applications.
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Design and Development of a Three-degree-of-freedom Parallel Manipulator to Track the Sun for Concentrated Solar Power TowersAshith Shyam, R Babu January 2017 (has links) (PDF)
In concentrated solar power (CSP) stations, large arrays of mirrors which are capable of changing its orientation are used to reflect the incident solar energy to a stationary receiver kept at a distance. Such mirrors are often called as heliostats. The receiver contains a heat absorbing medium like molten salt. By absorbing the thermal energy reflected from thousands of heliostats, the temperature would reach around 6000C and the heat can be used in thermal power plants to generate steam and thus run a turbine to produce electricity. One of the biggest advantages of CSP over conventional energy harvesting from Sun is that it can generate electricity during night for long hours of time from the thermal energy stored during daytime. This eliminates the usage of batteries or any other energy storing methods. The conversion efficiency is also high in CSP due to the high temperature achieved.
With prior knowledge of the station coordinates, viz., the latitude and longitude, the day of the year and time, the direction or the path of sun can be fully determined. Typically, the sun's motion is tracked by the azimuth-elevation (Az-El) or the target-aligned configuration heliostats. In both these approaches, the mirror needs to be moved about two axes independently using two actuators in series with the mirror effectively mounted at a single point at the centre. This arrangement causes the mirror to deform in presence of gusty winds in a solar field which results in loss of pointing accuracy. Typically a beam error of less than 2-3 mrad is desirable in a large solar field and this value also includes other sources of loss of pointing accuracy like gravity and wind loading. In order to prevent this, a rigid support frame is required for each of the heliostats.
In this work, two three degree-of-freedom parallel manipulators, viz., the 3-UPU wrist and 3-RPS, have been proposed to track the sun in central receiver systems. The main reasons for choosing a parallel manipulator as heliostat are its desirable characteristics like large load carrying capacity, high accuracy in positioning the mirror and easy to obtain the inverse kinematics and convenient for real time control. The proposed parallel manipulators support the load of the mirror, structure and wind loading at three points resulting in less deflection and thus a much larger mirror can be moved with the required tracking accuracy and without increasing the weight of the support structure. The algorithm for sun tracking is developed, extensive simulation study with respect to actuations required, variation of joint angles, spillage loss and leg intersection has been carried out. Using FEA, it is shown that for same sized mirror, wind loading of 22 m/s and maximum deflection requirement (2 mrad), the weight of the support structure is between 15% and 60% less with the parallel manipulators when compared to azimuth-elevation or the target-aligned configurations. A comprehensive study on stroke minimization of prismatic joints is carried out. It is found that a stroke of 700 mm is required for a 2 m x 2 m heliostat at Bangalore when the farthest heliostat is at a distance of 300 m from the tower. Although, there is an extra motor required to track the sun, the 3-RPS manipulator is better than the conventional methods if the mirror area per actuator criteria is taken into consideration.
Prototypes of the Az-El and 3-RPS heliostats were made with a mirror size of 1 m x 1 m. A PID controller implemented using MATLAB-Simulink and a low cost, custom made motor driver circuit is used to control the motion of the 3-RPS heliostat. The algorithm developed is tested on the prototype by tracking a point marked on the wall of the lab space and is found to have a tracking error of only 7.1 mrad. Finally, the actual sun tracking is carried out on the roof of a building reflecting the sun-light to a wall situated 6.72 m above and a distance of 15.87 m from the heliostats. The images are captured at various instances of time from 11:30 a.m. to 3:30 p.m. on October 15th and November 10th, 2016, tracking errors are quantified and it is demonstrated that the proposed 3-RPS parallel manipulator can indeed work as a heliostat in concentrated solar power plants.
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Design, Fabrication and Testing of a Novel Dual-Axis Automatic Solar Tracker System Using a Fresnel-Lens Solar ConcentratorAlmara, Laura Mabel 08 1900 (has links)
This thesis project investigates, analyzes, designs, simulates, constructs and tests a dual-axis solar tracker system to track the sun and concentrates the heat of the sunlight, using a Fresnel lens, into a small area, which is above of an evaporator, to increase the temperature of the seawater to convert it into freshwater. The dual-axis solar tracker was designed with the main objectives that the structure was portable, dismountable, lightweight, low cost, corrosion resistant, wires inside pipes, accurate, small size, follow the sun automatically, off-grid (electrical), use green energy (solar powered), and has an empty area right below of the lens. First, a 500 mm diameter flat Fresnel lens was selected and simulated based on an algorithmic method achieved by a previous PhD student at UNT using MATLAB®, to give the optimization lens dimensions. The lens profile was drawn with AutoCAD®, then output profile lens was simulated in COMSOL Multiphysics®. The objective was to provide the high efficiency, optimum and high precision of the focal rays and heat to the receiver of the evaporator. A novel dual-axis solar tracker system was then designed that is portable, dismountable, lightweight and corrosion resistant. The solar tracker tracks the sun in two axis of rotation automatically during the day time, maximizing the angles of inclination on each axis. After testing computer simulations, the dual-axis solar tracker system was constructed and tested. Last, a detailed cost analysis was performed of the entire project. The outcome of this work can be applied for desalination seawater purposes or other any Fresnel lens application that require a focal high temperature directed by dual-axis solar tracker system.
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Ολιστική ενεργειακή θεώρηση κτιρίωνΣακκά, Αγγελική 06 November 2014 (has links)
Στις χώρες της Ευρωπαϊκής Ένωσης ο κτιριακός τομέας απορροφά περίπου το 40% της συνολικής ενεργειακής κατανάλωσης, γεγονός που καθιστά απαραίτητο το λειτουργικό και φιλικό προς το περιβάλλον σχεδιασμό των κτιρίων, παράλληλα με τον περιορισμό των συνολικών ενεργειακών αναγκών τους για την εξοικονόμηση ενέργειας. Όσον αφορά τα ήδη υπάρχοντα κτίρια, μπορούν να γίνουν διάφορες παρεμβάσεις ώστε να επιτευχθεί η μέγιστη δυνατή εξοικονόμηση ενέργειας. Από την άλλη, η Ε.Ε.,στα πλαίσια της βιώσιμης ανάπτυξης και της προστασίας του περιβάλλοντος, έχει θέσει ως στόχο για το 2020 τα καινούρια κτίρια να είναι μηδενικών εκπομπών διοξειδίου του άνθρακα. Για την υλοποίηση του στόχου αυτού, είναι αναγκαίος ο σχεδιασμός των κτιρίων σύμφωνα με τις αρχές της βιοκλιματικής αρχιτεκτονικής, για την ελαχιστοποίηση των ενεργειακών τους αναγκών αλλά και η εφαρμογή συστημάτων Ανανεώσιμων Πηγών Ενέργειας για την παραγωγή θερμικής και ηλεκτρικής ενέργειας και την ελαχιστοποίηση έτσι των εκπομπών CO2 στην ατμόσφαιρα από τα ορυκτά καύσιμα.
Στην παρούσα διπλωματική εργασία, αναπτύσσονται στρατηγικές που αποσκοπούν στην αρμονική ένταξη των κτιρίων στο φυσικό περιβάλλον, παρουσιάζονται τα θέματα εξοικονόμησης ενέργειας στα κτίρια, διατυπώνονται οι βασικές παράμετροι για την επίτευξη ολιστικής ενεργειακής κάλυψης των κτιρίων και την προετοιμασία του επόμενου βήματος σχετικά με την ενέργεια στα κτίρια για το έτος 2020 και δίνονται νέες τεχνολογικές λύσεις που αναπτύχθηκαν στο εργαστήριο ηλιακής ενέργειας, με σκοπό την βέλτιστη αξιοποίηση της ηλιακής ενέργειας και των άλλων ΑΠΕ στα κτίρια.
Στα πλαίσια της πλήρους κάλυψης των κτιριακών ενεργειακών αναγκών από ΑΠΕ και της προώθησης των κτιρίων σχεδόν μηδενικής κατανάλωσης από συμβατικές ενεργειακές πηγές, μελετάται πειραματικά η συμβολή των φωτοβολταϊκών σε δυσμενή κλίση και προσανατολισμό. Εξετάζεται η συνεισφορά διάχυτων ανακλαστήρων στην ενεργειακή τους απόδοση, η επίδραση του υλικού της θερμομόνωσης και του περιορισμού των θερμικών απωλειών. Τέλος, εξετάζεται η αξιοποίηση κάθε τμήματος του κτιρίου που μπορεί να έχει θετική συμβολή στο ενεργειακό θέμα. Έτσι προτείνονται τρόποι τοποθέτησης φωτοβολταϊκών σε οριζόντιες και επικλινείς στέγες και στις προσόψεις των κτιρίων, με προσθήκη ανακλαστήρα όπου είναι δυνατό, που μπορούν να συνεισφέρουν στην επίτευξη μηδενικού ενεργειακού ισοζυγίου στα κτίρια. / In the countries of the European Union the building sector accounts for about 40% of the total energy consumption, so it is necessary that the buildings should be designed in a functional and environmentally-friendly way, in addition to the minimization of of the total energy needs to achieve energy savings. As for the existing buildings, they should be renovated so that maximum energy savings is achieved. On the other hand, the EU’s target for 2020 is that new buildings must be of zero carbon dioxide emissions. For the implementation of this goal, buildings should be designed according to the principles of bioclimatic architecture to minimize energy needs, but also systems of Renewable Energy Sources should be applied to produce thermal energy and electricity, in order to minimize carbon dioxide emissions from fossil fuels.
In the present thesis, strategies aiming to harmonic integration of buildings in the natural environment are developed, holistic energy saving aspects for buildings are presented, aspects regarding the next step to the target for 2020 are given, and some new designs of building integrated RES, investigated at the Solar Energy Laboratory, are suggested.
Approaching the holistic contribution of the renewable energy sources (RES) to buildings for total cover of their energy demand, and the achievement of nearly zero energy buildings, the contribution of photovoltaics in disadvantageous inclination and azimuth angle is experimentally studied. The contribution of diffuse reflectors to pV’s energy efficiency, the impact of thermal insulation materials and the impact of limitating the thermal losses to PV’s operation, are studied as well. Furthermore, the use of every single part of the building in order to contribute to its energy supply, is considered. Designs for photovoltaic integration on horizontal and inclined roofs and facades are suggested, combined with booster reflector if possible, aiming to achieve zero energy balance of buildings.
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Ny generation av GPS-transponder / New Generation of GPS-transponderLind, Hampus, Flenéus, Lukas January 2016 (has links)
Detta projekt har utförts på uppdrag av Saab Dynamics. Syftet med projektet var att skapa ett system för att ersätta den befintliga utrustning som fanns för att simulera radar vid testning av vissa vapensystem. Systemet byggdes upp med hjälp av GPRS, GPS och transportprotokollen TCP och UDP. Huvuddelen av arbetet berörde GPS och GPRS. Denna rapport är en redogörelse för systemets framtagning och de verktyg och metoder som användes, samt en fördjupning i ämnena GPS, GPRS och deras olika protokoll. Rapporten tar även kort upp alternativa lösningar till datasamtal. Slutsatsen som kan dras utifrån resultatet av detta projekt är att systemet fungerar och kan vara användbart i framtiden efter vidareutveckling. / This project has been carried out on behalf of Saab Dynamics. The purpose of the project was to create a system to replace the existing equipment for simulating radar when testing certain weapon systems. The system was created using GPRS, GPS and the transport protocols TCP and UDP. GPS and GPRS were used the most. This report is a description of the system's design and the tools and methods used to create it, as well as an in depth look into the subjects of GPS, GPRS and their various protocols. The report also briefly discusses some alternative solutions that could have been used instead of data calls. The conclusion that can be drawn from the results of this project is that the system works and can be useful in the future with further development.
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