Due to the ever increasing necessity to reduce our dependence on fossil fuels as feedstocks for polymeric materials, the work presented herein describes the investigation of new metal complexes as initiators for the formation of polyesters and polycarbonates from renewable monomers. These polymers are regarded as biodegradable and have the properties required to replace traditional plastics in applications such as food packaging, electronic devices, and medical biomaterials. Chapter one introduces previous literature relevant to the research on which this study focuses; ligands based on alkoxides, phosphine oxides and N-heterocyclic carbenes with alkoxide or amino pendant groups, as well as the metal complexes in which they are used. Current methods of polymerisation and copolymerisation and the initiators utilised are also examined. Chapter two contains the design and synthesis of [M(LR n)]m metal complexes where LR is [(R)2P(O)CH2CH(tBu)O]– and R is Ph or tBu. Divalent metal centres such as CoII and ZnII have been used for the formation of the studied compounds. Studies on their reactivity as initiators for polymerisations are also described. Chapter three presents the utilisation of di- and tridentate ligands, with one or two NHC species respectively, for the synthesis of [Mx(LY n)], where M is CuI, ZnII or TiIII and LY is an alkoxy-tethered NHC species or a ‘CNC’ tridentate ligands with an amino derivative as bridge. Their reactivity and ability to act as initiators for polymerisation reactions was also examined. Chapter four comprises overall conclusions of this work and the impact of these investigations. Chapter five outlines the experimental details and data for the compounds presented.

$$Saudi Arabia faces a challenging path to generate the electricity needed to keep growing while lowering its annual emissions. The emissions from electricity generation have grown significantly due to the rising electricity demand per capita and the abundant use of liquid fuels for electricity generation. The high demand is driven by the comparatively low costs of electricity, whereas the consumption of liquid fuels for generation is driven by the distorted market caused by strong subsidies for these fuels. By 2030, in a scenario free of reforms, liquid fuels would provide more than half of the fuel energy consumed for generation and would emit around 64% of the emissions. However, they would only represent 10% of the fuel costs at a domestic price. In this work, the effect and pertinence of reforms to the electricity price and to the fuels consumed for generation are addressed. Tariffs for countries with similar size of economy are taken as a reference. We found that raising the electricity price to international tariffs could reduce the demand projections for 2030 by up to 9%. Being the industrial sector more sensitive to price changes than the residential sector. The distortion between fuel price and consumption could be adjusted by increasing the domestic fuel prices to 30% of the international reference, which affects mainly liquid fuels. In this scenario, photovoltaic panels (PV) become a competitive substitute for gas turbines (GT). However, renewables would not exceed 43% of the total capacity and 28% of the energy generated without the early retirement of firm capacity. The resulting cost of emissions avoided by reforming fuel prices is of $43/ton CO2eq. Simultaneously reforming electricity prices and fuel prices would favor the penetration of renewables without additional costs of investment. Besides, the marginal cost of electricity would remain close to $45/MWh. Finally, reforming the price of fuel and exporting the saved fuel would derive in additional revenue of up to $6.6 billion by 2030, and would reduce the annual emissions by 2030 by up to 66 million tons of carbon dioxide. The economic gain from exporting the fuel saved by 2030 would be enough to relieve the additional cost in the electricity bill to the residents which represent 73% of the total consumption, through social programs.

Offshore wind farms are widely considered to become a cornerstone of energy transition for securing energy supply and tackling climate change simultaneously. But recent developments have demonstrated that the siting of offshore wind farms is far from being conflict-free, evoking confrontations with a number of stakeholder interests. Such real-life evidence implies a reductio ad absurdum, as offshore wind farms are generally supposed to be less contested than the ones onshore and therefore more convenient for local communities. By drawing on two case studies in Scotland and Germany (Argyll Array / Baltic 1), this thesis examines various conflicts that emerge from the siting of offshore wind farms and compares their underlying causes as well as their implications and institutional consideration in the planning process. In order to understand the conflicts over offshore wind farms, the research employs the epistemological framework of ‘space-related conflicts’ which turns the attention to conflicting interests, values and practices of affected actors as well as to the significance of structural and spatial conditions. Throughout the thesis, it will be argued that it is not the wind farms per se that are contested, but that the conflicts rather revolve around the places and spaces which are meant to be changed by the siting of offshore wind farms. The findings show that both case studies reflect similar conflicts, where adverse impacts on coastal tourism and environmental impacts turned out to be the key issues for local opponents from the public. However, even though key controversies are comparable, major differences result from the rationales that opponents invoke to substantiate their concerns and more dominantly from the existing planning frameworks which pre-structure the power relations and dynamics of public engagement. The comparative study concludes by suggesting some policy recommendations for future practices of dealing with affected actors. Therefore, the research findings do not just provide a contribution to the theoretical debates about the formation of resistance to renewables, but they also present practical implications relevant to policy-makers.

Support for electricity generation from renewable energy sources is one of measures aimed at switch of European economies from fossil fuels to renewables. In the past a lot of attention was paid to the theoretical assessment of different support schemes, however, analysis of the empirical data on those schemes is somewhat lacking. This thesis analyses assessment of two types of support schemes in three countries on empirical data. The main contribution of this work is (i) expansion of previously used methodology that analyses relationship between investments into electricity generation from renewable energy and the net present value of such investments, and (ii) inclusion of the Czech Republic into the list of observed countries. JEL Classification E61, O31, O33, O38, Q28, Q42 Keywords renewables, RES-E, photovoltaics Author's e-mail jbizek@gmail.com Supervisor's e-mail milan.scasny@czp.cuni.cz

When wind power and other intermittent renewable energy (IRE) sources begin to supply a significant part of the load, concerns are often raised about the inherent intermittency and unpredictability of these sources. In order to study the impact from higher IRE penetration levels on the power system, integration studies are regularly performed. The model package presented and evaluated in Papers I–IV provides a comprehensive methodology for simulating realistic time series of wind generation and forecasts for such studies. The most important conclusion from these papers is that models based on coarse meteorological datasets give very accurate results, especially in combination with statistical post-processing. Advantages with our approach include a physical coupling to the weather and wind farm characteristics, over 30 year long, 5-minute resolution time series, freely and globally available input data and computational times in the order of minutes. In this thesis, I make the argument that our approach is generally preferable to using purely statistical models or linear scaling of historical measurements. In the variability studies in Papers V–VII, several IRE sources were considered. An important conclusion is that these sources and the load have very different variability characteristics in different frequency bands. Depending on the magnitudes and correlations of these fluctuation, different time scales will become more or less challenging to balance. With a suitable mix of renewables, there will be little or no increase in the needs for balancing on the seasonal and diurnal timescales, even for a fully renewable Nordic power system. Fluctuations with periods between a few days and a few months are dominant for wind power and net load fluctuations of this type will increase strongly for high penetrations of IRE, no matter how the sources are combined. According to our studies, higher capacity factors, more offshore wind power and overproduction/curtailment would be beneficial for the power system.

This thesis reports on the research undertaken to investigate the reduction of the environmental impacts of plastic packaging through the effective selection and application of biopolymers during the pack design process. The principle objective of this research is to develop an understanding of the strengths and weaknesses of biopolymers as a packaging material and to develop a framework which enables biopolymers to be considered at each stage of the pack design process to enable their effective and appropriate selection and use.

Avec l’évolution technologique, le progrès de l’électronique de puissance et surtout l’enjeu économique, l’utilisation des machines asynchrones à cages ou à rotor bobiné occupe de plus en plus de place dans tous les domaines comme les entrainements électriques et la production d’énergie, leur robustesse, leur fiabilité et leur coût moins élevé sont particulièrement appréciés. Ces deux types d’actionneur en fonctionnement générateur sont la base des éoliennes actuelles.Néanmoins, malgré les travaux de recherches effectués ainsi que les améliorations apportées, ces machines demeurent des sièges potentiels de défaillances aussi bien au niveau stator que rotor. Les défauts les plus courants qui peuvent se produire dans la génératrice asynchrone à rotor bobiné du système éolien, au niveau rotor et stator sont : a) le court circuit sur les enroulements rotoriques et statoriques, b) les défaillances de roulements, c) les irrégularités statiques ou dynamiques de l’entrefer, d) les problèmes au niveau des balais et collecteurs. Ces types de défauts doivent êtres détectés, localisés à temps car ils peuvent endommager gravement le système. Durant ces dernières années, le diagnostic des défauts affectant les systèmes éoliens a été largement étudié. Un grand nombre de méthodes est disponible visant à améliorer la conception du système, à augmenter la qualité et la production d’énergie électrique et d’en diminuer les coûts. Malgré les résultats de la recherche, ces systèmes multi-Complexes restent encore les sièges de réflexions de plusieurs laboratoires tant qu’industriels qu’académiques.Ce rapport de thèse présente une nouvelle méthodologie de diagnostic de défauts combinant la méthode à base de modèle utilisant les équations mathématiques explicites du processus et la méthode sans modèle. Les machines électriques sont modélisées analytiquement par la méthode des circuits électriques magnétiquement couplés. L’objectif est de générer des données en fonctionnement sain et en fonctionnement défaillant de ses variables d’état. Tandis que la méthode sans modèle utilisée est l’analyse en composantes principales (ACP). Les deux méthodes sont implémentées sous Matlab/ Simulink. Les données de la machine acquises sont traitées et analysées par des méthodes statistiques pour générer des résidus. La détection et la localisation de défauts sur la machine sont obtenues par l’analyse des résidus de ses variables d’état. Les résidus sont des indicateurs de défaillance ou non du système étudié. L’analyse des grandeurs caractéristiques de la machine étudiée dans ce rapport de thèse par le biais de plusieurs résultats de simulation montre l’efficacité de la méthode ACP, aussi bien sur le plan de la détection que de la localisation, par rapport aux autres méthodes de diagnostic des machines électriques. / With the technological evolution, due to the progress of power electronics and the economic issue, the use of induction machines with squirrel cage rotor or wound rotor induction machine occupies more and more places in all areas such as electric drive system and power production due to their robustness, their reliability and their lower cost which are highly appreciated. These two types of actuator in generator operation are the basis of the current wind turbine.Nevertheless, in spite of those different researches as well as those improvements, these machines remain still the potential faults both in stator and rotor levels.The most current default which may occur in the wound rotor asynchronous generator of the wind system at the rotor and stator levels are: a) Inter-Turn short circuit on the rotor and stator windings; b) The bearings failures; c) Static or dynamic irregularities of the air-Gap; d) Brushes and collectors ring problems;These types of faults must be detected and localized in time because they may damage the whole system. During these last years, the faults diagnosis affecting the wind systems was widely studied.A large number of methods are available to improve the system design, to increase the quality and quantity of the electrical energy produced and to decrease this energy production costs. In spite of the literatures research results, these multi-Complex systems still remain the reflections seats of several industrial and academic laboratories. This thesis report presents a new faults diagnosis methodology combining the method using the explicit mathematical equations model of the process and the method without a prior model of the system which is the data statistical analysis. The electrical machines are analytically modeled by the method of magnetically coupled electric circuits.The objective is to generate data in healthy and faults functioning of its variable state. Whereas the method without model used is of the principal components analysis (PCA).Both methods are implemented under Matlab /Simulink. The data of the acquired machines are handled and analyzed through the statistical method in order to generate the residues.The detection and the localization of the machine faults are obtained by the residues analysis of its variable state. Residues are faults indicators or healthy on the studied system.The analysis of the characteristic size of the machine studied in this thesis report through several simulation results shows the efficiency of the method PCA, as well as in detection and localization, when compared with other diagnosis methods of electrical machines.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A presente dissertaÃÃo apresenta o desenvolvimento de uma ferramenta computacional de auxÃlio ao planejamento energÃtico chamada de GDHER (GeraÃÃo DistribuÃda de Sistemas HÃbridos de Energias RenovÃveis) A ferramenta pode ser utilizada sem custo uma vez que foi desenvolvido atravÃs do Calc um programa de planilha eletrÃnica semelhante ao Excel que faz parte de um pacote de vÃrios aplicativos livres da Broffice ApÃs identificar algumas limitaÃÃes dos principais softwares disponÃveis no mercado foi desenvolvida uma nova ferramenta adaptada à realidade brasileira principalmente voltada Ãs Ãreas rurais e isoladas que utiliza o portuguÃs como idioma e possui uma interface bastante amigÃvel facilitando sua compreensÃo e operaÃÃo pelo usuÃrio A ferramenta permite o usuÃrio fazer dimensionamento de algumas modalidades de geraÃÃo de energia elÃtrica a partir de tecnologias limpas como a solar fotovoltaica aerogeradores e biodigestores e atravÃs de uma anÃlise financeira esses sistemas sÃo comparados com a extensÃo da rede de energia elÃtrica permitindo que o usuÃrio obtenha um prognÃstico de viabilidade A ferramenta tambÃm permite fazer o dimensionamento e a anÃlise financeira de configuraÃÃes de sistemas hÃbridos como fotovoltaico-eÃlico fotovoltaico-biodigestor e biodigestor-eÃlico a fim de encontrar a configuraÃÃo Ãtima para o projeto Para validaÃÃo da ferramenta foi feito um estudo de caso e a partir da anÃlise financeira e anÃlise de sensibilidade a modalidade de fornecimento de energia elÃtrica mais viÃvel para os sistemas individualizados sÃo os biodigestores em seguida sÃo os mÃdulos fotovoltaicos e a rede elÃtrica e por Ãltimo sÃo os aerogeradores De acordo com a anÃlise financeira dos sistemas hÃbridos a configuraÃÃo mais lucrativo à 75% da demanda sendo atendida por biodigestores e 25% por mÃdulos fotovoltaicos Os resultados sÃo apresentados atravÃs de tabelas e grÃficos para melhor compreensÃo do usuÃrio Com todas essas caracterÃsticas a ferramenta proposta permite dimensionar sistemas com mÃxima eficiÃncia e menor custo obtendo assim sistemas mais adequados e confiÃveis tanto do ponto de vista tÃcnico como financeiro / This work presents the development of a computational tool to aid in energy planning called GDHER (Distributed Generation of Hybrid Systems for Renewable Energy) The program can be used without cost since it was developed through the Calc a program of electronic spreadsheet similar to Excel which is part of a package of several free applications of Broffice After identifying some limitations of the main software available on the market we obtained a new tool adapted to the Brazilian reality especially to rural and isolated areas which uses the portuguese as language and has an interface very user friendly facilitating the understanding and operation of the program by the user The program allows the user to do the scaling of some methods of electricity generation from clean technologies such as solar photovoltaics wind turbines and biodigesters and through a financial analysis these systems are compared with the extension of the network of electric energy allowing the user get a prognosis of viability The tool also allows the user to do the scaling and the financial analysis of some configurations of hybrid systems like photovoltaic-wind photovoltaic-digester and wind-digester in order to find the optimal configuration for the project For validation of the program it was done a case study and from the financial analysis and sensitivity analysis the modality of electric energy supply more viable for individualized systems are the digesters then are the photovoltaic modules and the electrical network and finally are the wind turbines According to the financial analysis of hybrid systems the configuration more profitable is 75% of demand being served by biodigesters and 25% by photovoltaic modules The results are presented using tables and graphs for better understanding of the user With all these features the tool allows to scale systems with maximum efficiency and lower costs thereby obtaining more appropriate and reliable systems both from the technical point of view as financial

This study analyses the potential of onshore wind power on the African continent. Appropriate socio-economic and geographical constraints as well as current technology’s efficiencies are applied in order to reach the desired result. The current energy access in Africa is described to illustrate the need of promoting the wind power penetration on the continent. The existing as well as the under construction wind farms are mapped. Thereafter, the methodology of approaching the resource assessment is analyzed. For the energy generation assessment, not only wind speed strength but also its probability of occurrence over a certain period of time is important and thus considered in this study. High resolution wind speed data from Vortex and lower resolution daily wind speed data are combined and processed in order to obtain a fine wind speed distribution and thus wind energy production generated by selected wind turbine models. The different categories of wind power potential are defined and evaluated. Additionally, screening criteria regarding the localization of wind farms are outlined and implemented through GIS analysis. Subsequently interactive maps are prepared. ArcGIS software is used in order to capture, store and manipulate the required data and to obtain a holistic view of the study. The study is conducted at a continental level using a 1km×1km (longitude, latitude) land-use grid as the finest resolution. Ultimately the results of this work are presented and compared with similar approaches and significant conclusions are drawn. Based on the analysis there are some countries that signify high yearly wind energy yield, such as South Africa, Sudan, Algeria, Egypt, Libya, Nigeria, Mauritania, Tunisia and Morocco, whilst Equatorial Guinea, Gabon, Central African Republic, Burundi, Liberia, Benin and Togo indicate the least wind power potential. Also important future work is suggested. / Denna studie analyserar potentialen för landbaserad vindkraft på den afrikanska kontinenten. Lämpliga socioekonomiska och geografiska begränsningar samt aktuella vindkraftverkens effektkurvor tillämpas för att nå det önskade resultatet. Den nuvarande tillgången till energi i Afrika beskrivs för att illustrera behovet av att främja vinkraftens penetration på kontinenten. De befintliga vindkraftverken såväl som de under konstruktion kartläggs. Därefter analyseras metoden för att närma sig resurs bedömningen. Bedömningen av energiproduktion och vindhastighet samt dess sannolikhet att inträffa under en viss tid är både viktigt och nödvändigt för denna studie. De olika kategorierna av potential för vindkraftverk definieras och utvärderas. Dessutom beskrivs kriterier av lokalisering för vindkraftverk och genomförs genom GIS-analys. Därefter förbereds interaktiva kartor. ArcGIS software används för att fånga, lagra och manipulera data som krävs samt för att få en helhetssyn av studien. Studien genomförs vid en kontinental nivå genom att använda en 1 km x 1 km (longitud, latitud) rutnät för markanvändning med den finaste upplösningen. Slutligen presenteras resultaten av detta arbete och jämförs med liknande metoder, viktiga slutsatser dras samt viktigt framtida arbete föreslås.

Renewable energy sources have started to substitute traditional energy sources in power sector, heating/cooling sector, and transportation sector. This paper explores the potential of renewable energy (mainly solar and wind) in Information and Communication Technologies (ICT) industry. The focus is on mobile telecommunication infrastructure segment, since it is a prime consumer of energy within the ICT industry. Moving towards solar or wind power sources might bring a major shift in the ICT industry – both on the technological level as well as the service provisioning level. An overview of innovative technological solutions for solar/wind powered telecom networks is provided with a discussion on technological feasibility of innovative standalone solar/wind powered base stations. The market value of these innovative solutions as well as potential power savings are estimated in the total addressable market, the potential market, and the real market. The industry attractiveness of the innovation solutions is assessed using the Porter’s five forces and SWOT frameworks. Furthermore, these innovative solutions are assessed for their potential diffusion likelihood in different scenarios. There are several potential driving forces for the transformation towards solar/wind powered telecom networks. Based on the most important driving forces, plausible scenarios of the future have been identified and analyzed. It is identified that the renewable energy driven transformation in the ICT industry can affect developments in other industries such as automotive, agriculture, healthcare, and transportation industries.