Dissertations / Theses on the topic 'Sustainable Energy'

Soaring energy demands are inevitable because of the continual increase in the global population as well as the greater reliance on electronic technologies. Current energy generation systems are highly dependent upon fossil fuels, for which the imminent risks and limitations are well known. First of all, we are confronting an energy crisis due to the depletion of these fossil fuels. However, current sustainable and renewable energy sources are not in a position to fully replace them as of yet. In fact, less than 10% of energy that is generated is from renewable energy sources, such as from hydroelectric power and solar power. Secondly, the emission of carbon dioxide (CO₂) and greenhouse gases (GhGs) from fossil fuels is currently at a serious level. As a result, today we are facing and experiencing abnormal climate changes. In order to mitigate and potentially resolve the energy crisis, energy generation systems are now shifting from fossil fuels to sustainable and renewable energy sources. Developments in energy harvesting technologies are considered to be a practical and promising way to deal with this crisis. Energy harvesting is a process that involves the generation of electrical energy by harnessing ambient environmental energy that is otherwise wasted. Generally, energy harvesting refers to a small amount of power for technologies such as portable electronic devices and wireless sensor networks. However, going forward, energy harvesting technologies beyond these would enable a bottom-up approach from 'the cell' scale to 'large farm' scale. My DPhil thesis deals with energy harvesting technologies that involve harnessing different environmental energy sources, such as solar and mechanical energy, using quantum dots for solar cells and polyvinylidene fluoride (PVDF)-based polymers for mechanical energy harvesting applications. Via novel approaches, such as the fabrication of a multi-junction quantum dot solar cell (QDSC) and the development of a room temperature polymer crystallisation method (solvent annealing), a significant enhancement in energy harvesting performance has been achieved. In addition, I have demonstrated more advanced energy harvesting devices by combining two alternative technologies together. Initially, a high efficiency QDSC is presented using the ferroelectric and piezoelectric coupling effect in PVDF-based polymer. Secondly, the integration of a QDSC with a mechanical energy harvester is demonstrated, which showed a combined enhancement by generating higher power beyond that observed from the individual components. Lastly, the thesis concludes with a demonstration of an application of these hybrid devices to self-powered electronics, which shows promise for future sustainable energy systems using energy harvesting technology.

Dissertação de Mestrado Integrado em Arquitetura, com a especialização em Arquitetura apresentada na Faculdade de Arquitetura da Universidade de Lisboa para obtenção do grau de Mestre.
Hoje em dia, as mudanças climáticas e o efeito estufa são questões globais importantes que precisam da cooperação entre os diferentes campos de estudo a serem resolvidos. A solução é bilateral, de um lado há um esforço significativo na União Européia para substituir os recursos convencionais de energia por energia renovável, como Solar, Eólica, Onda e Marés, enquanto outra solução é otimizar os consumos. Edifícios sustentáveis e edifícios com energia zero são as principais soluções em projetos de construção eficientes. Em caso de sustentabilidade na indústria de construção e arquitetura, o Zero Energy Building é uma tecnologia de última geração que aproveita os recursos locais de energia renovável enquanto é construída de forma otimizada com aquecimento, resfriamento e iluminação naturais para consumir água e energia no menor nível possível nível. Por outro lado, o roteiro europeu em diferentes campos do desenvolvimento urbano, cidade inteligente e cidades verdes, precisa de uma atenção considerável em edifícios sustentáveis e de energia zero. Neste projecto, um edifício sustentável foi concebido para funcionar como um centro de lazer público na antiga e turística região de Lisboa. Uma das principais questões da construção sustentável em pontos históricos é a morfologia da região e as situações geográficas que não podem ser alteradas devido ao impacto negativo que ela terá na aparência da região. Assim, nesta tese um lote vago da cidade é usado como o terreno do projeto e o desenho é realizado com base nas características, potenciais e restrições da zona. A funcionalidade do edifício inclui um health club, duas lojas e um restaurante, além de um espaço verde. Além disso, uma escadaria que passa pelo espaço verde aumenta a acessibilidade da região, que é um dos principais problemas nessa área de Lisboa.
ABSTRACT:Nowadays climate change and the greenhouse effect are important global issues which need the cooperation between different fields of study to be solved. The solution is bilateral, on one side there is a significant effort in the European Union to replace conventional energy resources with renewable energy such as Solar, Wind, Wave and Tidal while another solution is to optimize the consumptions. Sustainable buildings and zero-energy buildings are the main solutions in efficient building designs. In case of sustainability in building and architectural industry, Zero Energy Building is a state of the art technology which takes the advantage of local renewable energy resources while it is built optimally with natural heating, cooling, and lighting to consume water and energy in lowest possible level. On the other hand, European road map in different fields of urban development, smart city and green cities, needs a considerable attention in sustainable and zero energy buildings. In this project, a sustainable building is designed to operate as a public leisure center in the old and touristic region of Lisbon. One of the main issues in sustainable construction in historical spots is the morphology of the region and the geographic situations that cannot be changed because of the negative impact that it will have in the appearance of the region. So, In this thesis a vacant lot of the city is used as the project land and the design is fulfilled based on the zone characteristics, potentials and constraints. The functionality of the building includes a health club, two shops, and a restaurant in addition to a green space. Also, a stairway passing through the green space increases the accessibility of the region which is one of the key problems in that area of Lisbon.
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The Internet infrastructure, comprising both network and cloud facilities, has reached huge capacities but its development has not been compensated at the same rate as for its energy consumption. The energy consumption and the concomitant green house gases (GHG) emissions of the Internet are becoming major issues in the information and communication society. In such a context, there is a lack of a comprehensive energy-oriented paradigm for the Internet infrastructure that takes into account the absorbed energy, the emitted GHGs and the availability of renewable energy sources. This Thesis is focused on these very issues and tries to address the lack of such a paradigm in the Internet infrastructure by proposing energy models for energy-efficient architectures, energy-aware algorithms and protocols conceived to optimize the use of energy and minimize GHGs emissions, while preserving the traditional criteria such as network and datacenters load balancing to serve as many demands as possible and maximizing the system availability. In order to achieve the energy-oriented paradigm for the Internet infrastructure, specific problems were addressed step-wise, and then tied together in a comprehensive energy-oriented framework. Towards this goal, the power consumption of current and future energy-aware architectures was modeled through energy models that characterize the energy consumption of network equipment under different traffic loads, and power management strategies were assessed to allow network infrastructures to achieve advanced functionalities with limited energy budget. Integrated routing and wavelength assignment (RWA) schemes have been proposed (ILP formulations, heuristics and meta-heuristics, game theory, minimum affinity, minimum cut) in order to take advantage of different scenarios (complete or partial knowledge of network status, global control or individual selfishness of network elements, different requisites of computational and space complexity). Energy-aware RWA algorithms require an underlying routing protocol distributing up-to-date information about the energy consumption and GHG emissions of the network elements. Link state advertisement (LSA) messages of the OSPF-TE protocol have been extended to carry energy-related information. New TLVs have been added directly to the TE extensions of OSPF and flooded over the network. The connections re-optimization problem has been formulated as an iterative refinement process of multiple local search steps structured as a GRASP meta-heuristic, which re-reroutes connections to maintain the network traffic load balanced and free resources to serve incoming connections. To support the research tasks, a WDM-routed networks simulator, SimulNet, has been developed for the design and the evaluation of RWA and optimization algorithms. Energy-Farm, an energy manager for the modern and future grid/cloud data center infrastructures, was developed to reduce datacenters ecological footprint. Through the service-demand matching algorithm and the job aggregation capabilities, it allows turning off idle servers, while respecting both the demand requirements and the logical and physical dependencies. The risks related to energy-oriented attacks were pointed out for the first time and the potential impacts of network-based DoS attacks under the energy consumption perspective were evaluated. Finally, a holistic vision on the energy-oriented Internet is provided in which energy-efficient architectures are powered by a smart grid power distribution system employing renewable energy sources and are controlled by an intelligent energy-aware control plane, able to operate the Internet to minimize its ecological footprint. The research works leading to this Thesis delineate an energy-oriented paradigm for a sustainable high-performance Internet infrastructure that optimize the Internet ecological footprint while not disrupting the performance, towards sustainable society growth and prosperity.
La infraestructura de Internet, tanto de red como de centros de proceso de datos, ya alcanza un enorme volumen, pero este incremento no ha sido compensado con la misma rapidez en aspectos relacionados con el gasto energético. El consumo de energía y las emisiones de gases efecto invernadero (GEI) de Internet han pasado a ser un problema relevante en la sociedad de la información y las comunicaciones. En este entorno, falta un paradigma de largo alcance orientado a la energía, que considere el consumo de energía, las emisiones de GEI y la disponibilidad de recursos renovables. Esta Tesis está enfocada hacia estos problemas e intenta compensar la falta de ese paradigma en la infraestructura de Internet, proponiendo modelos energéticos para nuevas arquitecturas, así como algoritmos y protocolos conscientes de la energía para optimizar su uso y minimizar las emisiones de GEI, preservando los objetivos de calidad tradicionales de redes y centros de procesamiento de datos, así como asegurar la posibilidad de servir el mayor número de demandas posible y maximizar la disponibilidad del sistema. Para alcanzar una infraestructura de Internet orientada a la energía, se han solucionado problemas específicos y ligados a una estructura común de largo alcance. Hacia este objetivo, se ha modelado a través de modelos energéticos el consumo de los dispositivos bajo diferentes cargas, y se han valorado diversas estrategias de gestión de la energía para que las infraestructuras de red alcancen funcionalidades avanzadas con un presupuesto de energía limitado. Se han propuesto esquemas integrados de encaminamiento y asignación de longitud de onda (RWA) (formulaciones ILP, heurísticas y meta-heurísticas, teoría de los juegos, mínima afinidad, mínimo corte) para diferentes escenarios (conocimiento completo o parcial del estado de la red, control global o individual de los elementos de red, diferentes requisitos de computación y de espacio). Los algoritmos de RWA conscientes de la energía requieren un protocolo de encaminamiento que distribuya informaciones actualizadas sobre el consumo energético y las emisiones de GEI de los elementos de red. Se han desarrollado extensiones de los mensajes de aviso sobre el estado de la red (LSA) del protocolo OSPF-TE para transportar informaciones sobre la energía, añadiendo nuevos TLVs directamente a las extensiones TE de OSPF. El problema de la optimización de las conexiones se ha formulado como un proceso de refinado iterativo de pasos múltiples estructurado como una meta-heurística GRASP, que permite encaminar las conexiones para mantener el tráfico de la red balanceado y liberar recursos para servir posteriores conexiones. Para respaldar las tareas de investigación, se ha desarrollado SimulNet, un simulador de redes de encaminamiento de longitudes de ondas (WDM), para el diseño, optimización y evaluación de algoritmos de RWA. Se ha desarrollado EnergyFarm, un gestor de energía para los modernos centros de procesamiento de datos que, a través de un algoritmo de armonización entre demanda y servicio ofrecido y funcionalidades de agregación de las tareas, permite apagar los servidores no usados respetando los requisitos de las peticiones y las dependencias físicas y lógicas de los dispositivos. Se han evidenciado por primera vez los riesgos relacionados con los ataques orientados a la energía y se ha valorado su potencial impacto. Finalmente, se ha proporcionada una visión holística de Internet orientada a la energía, en la que arquitecturas eficientes energéticamente están alimentadas por una smart grid con fuentes renovables y controlada por un plano de control inteligente y consciente de la energía, capaz de operar en Internet para minimizar su huella ecológica. Los trabajos de investigación de esta Tesis conducen hacia un paradigma orientado a la energía para una infraestructura sostenible de Internet de alto rendimiento que optimice su huella ecológica sin afectar el rendimiento.

This research addresses the sustainable energy venture through an exploration of how it manages the opportunities and obstacles it faces during firm development. The literature revealed a variety of perspectives on the entrepreneurial opportunity. It was shown that linking market failures to environmental entrepreneurial opportunities failed to resolve the paradox that market failure can cause both opportunities and obstacles to entrepreneurial endeavour. It was posited that this position was resolved by focusing on the act of opportunity/creation/development by the entrepreneurial process which distinguishes opportunities from obstacles in the endeavour to create and capture value. The research process required the development of a conceptual framework of the entrepreneurial process of firm development. The conceptual framework was enabled by drawing on the resource based view and evolutionary theory and linked the entrepreneurial process with value creation and capture. This framework guided case-study research and analysis from fuel cell and renewable energy sectors. This was followed by an investigation of opportunities and obstacles in sustainable energy through an analysis of technology and market challenges to value creation. Through managing the research in parts it became possible to address the primary research question. Several strategies were found for how new ventures manage various opportunities and obstacles. However it was also clear that the entrepreneurial process is holistic and should be evaluated as a whole for efficient and appropriate resource use. Interactions between firm and business environment were shown to influence firm and industry development.

Secondary fibre paper mills are significant users of both heat and electricity which is mainly derived from the combustion of fossil fuels. The cost of producing this energy is increasing year upon year. These mills are also significant producers of fibrous sludge and reject waste material which can contain high amounts of useful energy. Currently the majority of these waste fractions are disposed of by landfill, land-spread or incineration using natural gas. These disposal methods not only present environmental problems but are also very costly. The focus of this work was to utilise the waste fractions produced at secondary fibre paper mills for the on-site production of combined heat and power (CHP) using advanced thermal conversion methods (gasification and pyrolysis), well suited to relatively small scales of throughput. The heat and power can either be used on-site or exported. The first stage of the work was the development of methods to condition selected paper industry wastes to enable thermal conversion. This stage required detailed characterisation of the waste streams in terms of proximate and ultimate analysis and heat content. Suitable methods to dry and condition the wastes in preparation for thermal conversion were also explored. Through trials at pilot scale with both fixed bed downdraft gasification and intermediate pyrolysis systems, the energy recovered from selected wastes and waste blends in the form of product gas and pyrolysis products was quantified. The optimal process routes were selected based on the experimental results, and implementation studies were carried out at the selected candidate mills. The studies consider the pre-processing of the wastes, thermal conversion, and full integration of the energy products. The final stage of work was an economic analysis to quantify economic gain, return on investment and environmental benefits from the proposed processes.

Bio-derived materials have attracted increased attention recently due to not only the sustainability, care-for-the-environment concerns, but also their naturally possessed unique structures, interesting mechanical properties, and abundant functional groups. These features endow them to potentially solve the issues that the next-generation high-capacity conversiontype lithium-ion batteries (LIBs) are facing, including but not limited to 1) great volume variation during charge/discharge for most conversion-type active materials (AMs), causing electrode pulverization, a phenomenon that active material particles are disassociated with the electrode and 2) serious shuttle effect brought by the dissolution of poly-intermediates into the electrolyte, leading to AMs loss, self-discharging, capacity fading, and shortened battery life. Bio-derived materials could provide strong binding forces and excellent mechanical strength to maintain the electrode integrity for high-capacity anodes, such as aluminum (Al) and silicon (Si) anodes. Meanwhile, Bio-derived materials possess abundant functional groups which could suppress the shuttle effect for high-capacity cathodes, such as lithium-iodine (Li-I2) batteries. These unique chemical, physical and mechanical properties of bio-derived materials make them promising in developing next-generation high-capacity LIBs. In the first study, aluminum with a high specific capacity, abundance, and electrical conductivity had been used as an active material to react with lithium ions and the electrical current collector simultaneously to save cost in the battery manufacturing process. However, its almost 100% volume variation will lead to serious electrode pulverization during lithiation/delithiation and reduce the cycle life of Al anode. Herein, a novel and robust biomassderived poly(furfuryl alcohol)/carbon black binder composite is prepared and applied on the surface of aluminum foil, and this hybrid Al anode had shown a superior 150 cycle life than unprotected Al anode that only can last for 25 cycles under a cut-off capacity loading of 400 mAhꞏg-1. This fast, quick, green, and low-cost method is potentially capable of solving the pulverization issue of high-capacity LIBs with minimal alternation on the existing battery manufacturing process. Instead of adopting complex and costly electrode structural modification methods, applying functional binders has the least impact on the existing LIBs fabrication process. Silicon has the highest theoretical capacity of 4200 mAhꞏg-1 but with an even more significant volume variation (~300%) than that of Al. Natural binders extracted from abundant plants provide effective strategies to solve the pulverization of silicon particles during charge/discharge processes. Green and abundant glutinous rice that had been used to build the Great Wall inspired the use of its main ingredient inside: amylopectin (AP). AP is a long and highly branched bio-polymer rich with carboxylic groups (-COOH) and hydroxyl groups (-OH), which can covalently bond with the SiOx on the Si nanoparticles. Also, its viscoelastic property allows it to accommodate the drastic volume variation of Si during charge/discharge. The asprepared Si-AP can uphold a high discharge capacity of 1517.9 mAhꞏg-1 at a rate of 0.1 C after 100 cycles, in which cycling stability is much higher than that of using traditional polyvinylidene fluoride (PVDF) and aqueous carboxymethylcellulose (CMC) binders. Okra, popularly known as Lady’s finger, is another commonly cultivated crop with a thick and slimy mucilage because of rich polysaccharides in it. It can be extracted and separated from the pods with a facile method and used as a binder, named okra gum (OG), showing great potential in addressing the volume variation of Si during lithiation/delithiation. Benefiting from its complex compositions and highly branched structure with rich hydroxyl groups, and viscoelastic properties, OG is able to form an interconnected network that bonds and holds the Si nanoparticles, conductive carbon, and the current collector. The as-prepared Si-OG electrode exhibits a discharge capacity of 1434 mAhꞏg-1 at a rate of 0.1 C after 50 cycles and is about 1.5 times greater than that of the Si-CMC electrode. These two studies suggest that bio-derived binder materials are able to construct more reliable LIBs with high-capacity, and both the extractions of AP and OG are greener, quicker, and cheaper than refined CMC binder. In contrast to famous lithium-sulfur (Li-S) batteries, lithium-iodine (Li-I2) batteries have also drawn great attention recently due to their high energy and power density, and iodine is low in cost and abundant. However, like Li-S batteries, Li-I2 batteries also suffer from the notorious shuttle effect, in which the dissolved iodine will leak from the cathode and diffuse to the lithium anodic side and cause self-discharge and eventually capacity fades. Here, an instant coffeederived heteroatom-rich honeycomb-like carbon filter is prepared to confine the dissolved iodine on the cathode region. In addition, this as-prepared bio-derived interlayer can bring Li-I2 battery with additional surface pseudo-capacity and results in a robust and highly reversible capacity of 224.5 mAhꞏg-1 at a rate of 10 C, and great capacity retention of 120.2 mAhꞏg-1 after 4,000 cycles. In summary, the explored bio-derived materials demonstrate the potential of solving the challenges that next-generation high-capacity lithium-ion batteries possess. Besides the facts that these materials are sustainable, green, and low cost, the extraction and electrode preparation processes are also beneficial to the environment and the operators. More importantly, these materials with environmentally friendly fabrication processes can be further developed into industrialized products for future high-capacity LIBs.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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This dissertation examines the concept of sustainable energy within a urban design context. In essence, the research aims to answer the question: “what role does the city’s built environment morphology play, if any, in the sustainability of its energy system?†. To answer this question, I first derive an operational definition of sustainable energy in the post carbon era: maintaining the capability to provide non-declining energy services in time. Providing non-declining energy services, in an urban design context, depends on urban morphologies ability to save and conserve energy, be efficient and produce energy from renewable sources without decrease the level of energy services. In other words we can think of a more sustainable energy urban built environment as one that saves energy, is efficient and produces energy from renewable resources per unit of throughput, with energy sustainability measured by urban morphologies energy performances and throughput measured by land unit. This is a normative framework. It can only indicate relative levels of sustainable energy of urban morphologies. Within a specific urban system this framework can allow us to measure which part of the city produce more sustainable energy urban patterns. To employ this framework I utilize a Spatial Pattern Oriented Modelling approach. The energy performance of an urban morphology metric comes from its basis in the international debate on urban energy sustainability, its ability to account for a specific aspect of sustainable energy and the possibility for its derivation from the spatial pattern analysis. Drawing from the large research based on exploring the role of the urban morphology on urban energy system, I derived several spatial patterns indicators that assess the influence of urban morphology on energy performances of urban settlements. These spatial patterns metrics, combined, enable the exploration of sustainable energy within a given urban morphology configuration. I apply the framework to a case study area located in northern Italy between Alps, the transect Trento-Pergine-Valsugana, utilizing data from different sources and exploring the possibilities given by a high-resolution 3D spatial database, a LiDAR survey, and by a geolocalized human activities database, internet 2.0, for the urban morphology analysis with focus to energy. The Principal Component Analysis is used to estimate the correlation between different spatial patterns indicators while a ranking system, based on arbitrary thresholds and classes, is used to visually compare the scores of different sustainable energy performances of urban morphologies.

This dissertation examines the concept of sustainable energy within a urban design context. In essence, the research aims to answer the question: “what role does the city’s built environment morphology play, if any, in the sustainability of its energy system?”. To answer this question, I first derive an operational definition of sustainable energy in the post carbon era: maintaining the capability to provide non-declining energy services in time. Providing non-declining energy services, in an urban design context, depends on urban morphologies ability to save and conserve energy, be efficient and produce energy from renewable sources without decrease the level of energy services. In other words we can think of a more sustainable energy urban built environment as one that saves energy, is efficient and produces energy from renewable resources per unit of throughput, with energy sustainability measured by urban morphologies energy performances and throughput measured by land unit. This is a normative framework. It can only indicate relative levels of sustainable energy of urban morphologies. Within a specific urban system this framework can allow us to measure which part of the city produce more sustainable energy urban patterns. To employ this framework I utilize a Spatial Pattern Oriented Modelling approach. The energy performance of an urban morphology metric comes from its basis in the international debate on urban energy sustainability, its ability to account for a specific aspect of sustainable energy and the possibility for its derivation from the spatial pattern analysis. Drawing from the large research based on exploring the role of the urban morphology on urban energy system, I derived several spatial patterns indicators that assess the influence of urban morphology on energy performances of urban settlements. These spatial patterns metrics, combined, enable the exploration of sustainable energy within a given urban morphology configuration. I apply the framework to a case study area located in northern Italy between Alps, the transect Trento-Pergine-Valsugana, utilizing data from different sources and exploring the possibilities given by a high-resolution 3D spatial database, a LiDAR survey, and by a geolocalized human activities database, internet 2.0, for the urban morphology analysis with focus to energy. The Principal Component Analysis is used to estimate the correlation between different spatial patterns indicators while a ranking system, based on arbitrary thresholds and classes, is used to visually compare the scores of different sustainable energy performances of urban morphologies.

This dissertation proposes an approach to energy that transcends the focus on energy as a mere technical economic or engineering problem, is connected to sociological theory as a whole, and takes issues of equality and ecology as theoretical starting points. In doing so, the work presented here puts ecological and environmental sociological theory, and the work of environmental justice scholars, feminist ecologists, and energy scholars, in a context in which they may complement one another to broaden the theoretical basis of the current sociology of energy. This theoretical integration provides an approach to energy focused on energy justice. Understanding energy and society in the terms outlined here makes visible energy injustice, or the interface between social inequalities and ecological depredations accumulating as the social and ecological debts of the modern energy regime. Systems ecology is brought into this framework as a means for understanding unequal exchange, energy injustice more generally, and the requirements for long-term social and ecological reproduction in ecological terms. Energy developments in Ecuador and Cuba are used here as case studies in order to further develop the idea of energy justice and the theory of unequal ecological exchange. The point is to broaden the framework of the contemporary critical sociology of energy, putting energy justice at its heart. This dissertation contains previously published and unpublished co-authored material.

Lithuania has limited domestic energy resources, and is therefore, heavily dependent on imports of oil products and natural gas. Lithuania imported around 90% of its oil and 100% of natural gas in 2009. Particularly, after the accession to the European Union (EU), and decommissioning of main electricity generation source Ignalina Nuclear Power Plant (NPP), energy security became one of the main concerns. Therefore, it is vital to evaluate different pathways the country could take in order to achieve desirable energy security, and ensure sustainable development of the energy system in Lithuania. The study was conducted using LEAP, the Long range Energy Alternatives Planning System, to develop energy policy analysis. Different scenarios presented in the report show how Lithuanian energy system would react in given different circumstances. Moreover, it demonstrates how implementation of existing energy projects separately or combined together would affect the level of energy security and sustainability in Lithuania. The research shows that current government policies could lead Lithuania to more secure and sustainable energy future. However, in a long run higher investments in renewable energy might be more environmentally and economically competitive alternative.

This study focuses on the village of Los Tumbos. It is located in a mountainous area of Cuba, farfrom the closest electric grid. The village consists of a few public buildings and around 80households. The public buildings and ten of the households are located in a small center that liesclose to a river. The villagers today use a few solar cells in order to electrify some importantpublic buildings and there is also an old hydropower plant which does not work at present. Theaccess to wind and biomass is very low, which makes the use of techniques involving theseunsuitable for electricity production. The options that will be used to electrify the dispersedhouseholds are solar cells. Combined with battery storage these works well, constantly able todeliver the electricity demand. They can also be used separately without connection the eachother, which eliminate the need to create a local grid. For the center of the village the locationclose to the river implies that the use of hydropower is a suitable option in order to power itsbuildings. Solar water heaters can also be used in order to give access to hot water and furtherincrease the life standards of the villagers.The model calculates the electricity demand in the village and estimates the sizes of theproduction facilities needed to meet the demand on the grid. In the model the load curves bothfor the dispersed households and the center of the village will be calculated. By using these resultsthe number of batteries and solar cell modules for the dispersed households can be calculated.For the center of the village the possible output from the hydropower plant can be calculated andthe number of collectors needed in the solar water heater system could also be estimated.From the model three different load curves were examined showing the peak-demand and thedaily average energy consumption for the demand levels. For each of the different levels the sizeof the energy conversion facilities were estimated showing the number of solar cells, batteries andsolar water heater collectors needed for the different levels. Any unambiguous result about asuitable demand level and by that the number of solar cells, collectors and batteries for LosTumbos cannot be selected without a complementary study of the economics available. This issince the economics is a very important factor in the decision. The output from the hydropowerplant is not dependent on the demand levels and it is capable of delivering a maximal power of2616 W and an average daily electrical consumption of 62,8 kWh per day. This result is verydependent on water flow and the available head and since the records were bad it needs to bereevaluated using records of the water flow from a longer time period, and an onsitemeasurement of the water head.

Climate change, pollution, unprecedented population growth, geopolitical tensions and rapid technological development are intrinsically connected to the nature, level and availability of global energy, which shapes present and future aspects of human society. Particularly, in a society where global energetic demand is continuously rising and the awareness of the negative impact of fossil fuels on the environment is becoming widespread, the exploitation of renewable sources for the generation of sustainable energy is highly needed. In this regard one key requirement for an effective deployment and expansion of renewable energy in the global energy market is represented by its ability to conveniently convert and store the energy derived from intermittent sources, in order to guarantee a constant supply to the electric grid. The technologies for the energy conversion and storage present various degrees of maturity, each one having specific advantages and disadvantages depending on the type of application and energetic source. This thesis aims to give a tiny contribution to the complex problem of energy conversion and storage, through the design, characterisation and testing of electrocatalytic materials for water electrolysis, photoelectrochemical water splitting and direct methanol fuel cell. It is expected that the first two processes will play an important role in the future as convenient technologies for the conversion of solar and wind power into chemical energy in the form of hydrogen. The third process is regarded as promising way to convert the renewable chemical energy in the form of methanol into electrical energy. At the core of the research lies the design and development of electrocatalysts, which are directly responsible for lowering the reaction overpotentials and ultimately increasing the overall efficiency of the processes. As such, in this thesis three materials were synthesised using straightforward methodologies and evaluated as electrocatalysts for the alkaline hydrogen evolution, the photoelectrochemical oxygen evolution and the alkaline methanol oxidation. Their performances were directly linked to the morphological and structural properties which in turn significantly affected the nature of active sites. For the first work reported in Chapter 3, a material based on a mixed cobalt nickel sulphide nanoparticles supported onto Ni foam showed high activity toward the hydrogen evolution reaction, with a required small overpotentials of 163 mV at a current density of 10 mA/cm2 in 1.0 M KOH electrolyte. This value compares well with the best existing hydrogen evolution reaction electrocatalysts based on non-noble elements. Moreover the catalyst showed good durability which was tested under chronoamperometric conditions, maintaining an optimal performance for 72 hours. The origin of such high activity was attributed to the existence of an optimal nickel-cobalt sulphide ratio at the surface of the electrode, which was obtained by selecting the appropriate temperature and time of thermal annealing of the material. This optimal presence of the biphasic nickel-cobalt sulphide nanoparticles led to high electrochemically active surface area and small charge transfer resistance, as evidenced by the extensive characterisation analysis carried out on these materials. For the second work reported in Chapter 4, a WO3/Co3O4 photoanode was successfully synthesised via a facile sol-gel method and tested for the photoelectrochemical oxygen evolution. It was found that the degree of crystallinity of the cocatalyst influenced heavily the photoelectrochemical activity towards the oxygen evolution. In particular, a poorly crystalline structure of Co3O4 led to an improvement of up to 40% in photocurrent generation compared to the bare WO3. Interestingly, the highly crystalline Co3O4 significantly suppressed the photocurrent generation, as a result of the creation of an unfavourable band alignment, with a dramatic increase in the charge recombination at the interface. Finally, for the third and last work reported in Chapter 5, ultra-small Pt nanoparticles embedded on a 3D structure composed of CeO2, NiO and Ni foam was synthesised and tested as electrocatalyst for the alkaline methanol oxidation reaction. The generated catalyst showed extremely high activity for the alkaline methanol oxidation, with mass and geometric current density values of 1160 mA/mgPt and 202 mA/cm2, whose values are among the highest ever reported for Pt-based materials. It was demonstrated that the unique morphological architecture and existence of a synergistic effect between Pt and adjacent CeO2 nanoparticles contributed decisively to the observed high performance. Particularly the presence of defective and poorly crystalline CeO2 nanoparticles was beneficial to the efficient oxidative removal of the CO from the Pt active sites which resulted in a higher durability of the electrocatalyst. Moreover, the concomitant presence of the superficial Ni(OH)2 was thought to contribute to the supply of OH species to the Pt, which act as reactants for the CO removal. The most active electrocatalyst was subjected to stability test, retaining 40 % of the initial geometric current density after 6 hours, and quite surprisingly the activity could be totally restored through straightforward CV scans in 1.0 M NaOH electrolyte.

To ensure energy independence of Ukraine on the way to sustainable development one of the priority areas is the implementation of alternative energy projects. Rising energy demand raise the issues of a gradual shift from traditional technologies that involve the use of mainly energy assets and passive energy networks to fundamentally new solutions, focused on the widespread use of renewable energy sources (RES) and active networks that can provide services for transfer, storage and conversion of electricity.

Titanium dioxide (TiO2) is a wide-band gap semiconductor with band gaps around 3 eV for the principal polymorphs rutile and anatase. Although TiO2 has been commercialized in applications that utilise its special chemical and optical properties, its band gap should be reduced to improve its performance, especially as an active photo catalyst. Band gap engineering of TiO2 has therefore attracted many researchers looking to extend its applicability as a functional material. Reduction of TiO2 introduces oxygen vacancies, initially forming disordered TiO2–x and eventually forming the ordered Magnéli phases TinO2n–1 ( n 1 x ), which have been commercialized in battery electrodes. Reduction of TiO2 under a hydrogen atmosphere is a promising method which can increase the visible-light absorption efficiency of TiO2, but the mechanism by which hydrogen exposure enhances its electrical properties is subject to controversy. TiO2 can also be reduced by carbon-containing gases, including CO, CO2 and CH4. Using methane as a reducing agent has the advantage of consuming a greenhouse gas in favour of producing oxygen deficient TiO2 for cocatalyst free methane decomposition processes. Reduced rutile is bluish in colour, while reduced anatase is black. Slightly reduced anatase or rutile nanoparticles have been reported to be yellow. Hydrogen-modified TiO2 In the first part of the project, carried out at Griffith University, the focus was on fundamentals, particularly the production and influence of O vacancies under vacuum and hydrogen, aiming to understand the action of hydrogen as a reducing agent. Oxygen deficient TiO2‒x was produced by exposing rutile to hydrogen at temperatures up to 500 C. Magnéli phases were produced by exposing rutile to vacuum at temperatures up to 1100bC. The absorption and desorption of hydrogen were studied by thermogravimetric analysis at temperatures up to 730 C, with simultaneous mass spectrometry measurements. The structural modifications caused by hydrogen absorption and desorption were confirmed by in-situ x-ray powder diffraction measurements at temperatures up to 1100 C. It was found that the Magnéli phases produced also absorbed hydrogen and desorbed higher amounts than hydrogen-modified rutile. Recent explanations of the enhancement of the electrical properties of hydrogen-modified TiO2 propose mid-band gap states just below the conduction band and, based on the absence of obvious structural changes in x-ray diffraction measurements, relate these to surface disorder. The reasoning behind this conclusion is that the volume of material subject to structural change must be too small to contribute noticeably to the measured diffraction pattern. On the other hand, x-ray diffraction is insensitive to light elements such as oxygen. In-situ high-resolution neutron powder diffraction with deuterium in place of protium was carried out to test this hypothesis, based on the high neutron scattering length of O relative to Ti. A small contraction of the unit cell was found, accompanying the introduction of oxygen vacancies. By refining the O occupancy, it was determined that TiO2–x with x = 0.2 (equivalent in stoichiometry to a Ti5O11 Magnéli phase) was formed under 50 bar of deuterium at 500 C. This indicates that vacancies are introduced throughout the volume of the TiO2 particle, because a surface-only structural change would not be resolvable. The sample was bluish in colour as is usual for reduced rutile. It therefore appears that the explanation of enhanced electrical properties owing to surface-only processes is wrong, or at best incomplete. Reduction and Carburization of TiO2 by Methane The second part of the project, carried out at University of California Santa Barbara, focused on applications of reduced TiO2. TiO2 reduction was studied using methane-containing gas (CH4-H2-Ar). In addition, catalytic decomposition of methane to hydrogen and carbon over reduced TiO2 surface was investigated. Oxide reduction using methane-containing gas occurs through adsorption and dissociation of methane with formation of adsorbed active carbon. Methane decomposition on metal oxides and solid solutions has been limited by carbon formation and deactivation. Carbon formation in the alkane dehydrogenation process is problematic because even small amounts of carbon can deactivate catalytic surfaces by physically blocking active sites. Methane pyrolysis experiments were performed in a lab-scale fixed-bed reactor and molten salt environment by flowing CH4 through a molten halide (LiCl-KCl eutectic mixture)/TiO2(Degussa P25) mixture. The highest degree of CH4 conversion (~34% initially) occurred at 1000 °C, but owing to catalyst coking and sintering fell quickly to ~20.0%. Temperature-programmed reaction (TPR) was also performed on the molten salt/additives mixture. The H2 yield of the LiCl-KCl/TiO2 mixture was not much higher than that of plain salt. The salt mixture turned yellow and TiO2 particles precipitated in the bottom of the reactor. Since it is known that CH4 reduces TiO2 to TiO2–x, the yellow colour of the molten salt/TiO2 mixture was likely due to the presence of TiO2–x. The higher density of the TiO2 particles relative to the molten salt, and ability to be wetted by the molten salt, caused them to settle in the reactor. It is concluded that the precipitation of TiO2 particles in the bottom of the reactor caused the low yield of the salt/catalyst mixture. More experiments should be done to confirm the catalytic activity and stability of TiO2 and Magnéli phases for methane pyrolysis.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
Full Text

Energy Management strategy for sustainable regional development has been selected as the topic of my research due to the fact that energy demand alongside with energy dependency have been continuously growing from a long term perspective. Sustainable development is defined by three imperatives – energy efficiency, ecology and security. Review of the current state and analysis of historical trends in Energetics at global and regional level are covered in this research. Results of the Multi-Criteria Decision Analysis introduce a set of implications and recommendations for Energy Management strategy in the Czech Republic.

IoT systems have been massively infiltrating our everyday's life for various applications. One of the main constraints inhibiting the further development of these applications is the limited autonomy of present day batteries. Moreover, energy sustainability is a crucial requirement for systems employed in critical mission applications. A widely used approach to increase the autonomy of IoT systems is the use of renewable sources of energy such as solar, wind, heat, and others to power the devices. For instance, one of the most widespread solutions for wireless sensor nodes is the use of solar panels, which can provide reasonable power input. Their efficiency is determined by the panel's material that defines the conversion efficiency. Renewable sources of energy are too erratic to provide complete system reliability unless over-dimensioned. In reality, energy supply is often limited, which causes the need for adaption of the node operational strategy to ensure the functional reliability of the system. However, the unreliable nature of renewable energy causes several challenges, which we address in this work. In particular, this thesis investigates the effect of battery imperfections caused by inner diffusion processes in the battery on the energy harvesting wireless device operation and effective energy-balancing strategies for different scenarios and system types. We propose 1) the transmission strategy, that takes into account the battery properties (leakage, charge recovery, deep discharge, etc.), and reduces the data losses and discharge events; 2) adaptive sampling algorithms, that balances the erratic energy arrivals, validated on the industrial data-logger powered by a solar panel; and 3) energy cooperation in WSN and Smart City contexts. We also focus on critical-mission IoT systems, where the freshness of delivered packets to the monitoring node by the information sources (communication nodes) is the important parameter to be tracked. In this context, we set the objective of age of information minimization taking into account the battery constraints, asymmetry in reliability of information sources, and stability of energy arrivals, that is, the energy harvesting rate. This array of strategies covers a wide range of applications, scenarios, and requirements. For instance, they can be applied to a smart city represented as a large system of interconnected smart services, or a WSN employed for critical mission applications. We demonstrated that the knowledge of battery and environmental characteristics, and the asymmetric properties of a system is beneficial for designing transmission/sensing strategies.
I sistemi IoT si sono massivamenti entrati nella vita quotidiana per varie applicazioni. Uno dei principali vincoli che inibiscono l'ulteriore sviluppo di queste applicazioni è l'autonomia limitata delle batterie attuali. Inoltre, la sostenibilità energetica è un requisito cruciale per i sistemi impiegati in applicazioni mission-critical. Un approccio ampiamente utilizzato per aumentare l'autonomia dei sistemi IoT è l'uso di fonti energetiche rinnovabili come solare, eolico, termico e altri per alimentare i dispositivi. Ad esempio, una delle soluzioni più diffuse per i nodi di sensori wireless è l'uso di pannelli solari, che possono fornire un ragionevole input di energia. La loro efficienza è determinata dal materiale del pannello che definisce l'efficienza di conversione. Le fonti energetiche rinnovabili sono troppo irregolari per garantire la completa affidabilità del sistema se non sovradimensionate. In realtà, l'approvvigionamento energetico è spesso limitato, il che causa la necessità di adattamento della strategia operativa del nodo per garantire l'affidabilità funzionale del sistema. Tuttavia, la natura inaffidabile delle energie rinnovabili provoca diverse sfide, che affrontiamo in questo lavoro. In particolare, questa tesi studia l'effetto delle imperfezioni della batteria causate dai processi di diffusione interna della batteria sul funzionamento del dispositivo wireless per la raccolta di energia e strategie efficaci di bilanciamento dell'energia per diversi scenari e tipi di sistema. Proponiamo 1) la strategia di trasmissione, che tiene conto delle proprietà della batteria (perdite, recupero della carica, scarica profonda, ecc.) E riduce le perdite di dati e gli eventi di scarica; 2) algoritmi di campionamento adattivo, che bilanciano gli arrivi irregolari di energia, validati sul data logger industriale alimentato da un pannello solare; e 3) cooperazione energetica in contesti WSN e Smart City. Ci concentriamo anche su sistemi IoT di missione critica, in cui la freschezza dei pacchetti consegnati al nodo di monitoraggio da parte delle fonti di informazione (nodi di comunicazione) è il parametro importante da tracciare. In questo contesto, fissiamo l'obiettivo dell'età della minimizzazione delle informazioni tenendo conto dei vincoli della batteria, dell'asimmetria nell'affidabilità delle fonti di informazione e della stabilità degli arrivi di energia, ovvero della velocità di raccolta dell'energia. Questa serie di strategie copre una vasta gamma di applicazioni, scenari e requisiti. Ad esempio, possono essere applicati a una città intelligente rappresentata come un grande sistema di servizi intelligenti interconnessi o come WSN impiegato per applicazioni mission-critical. Abbiamo dimostrato che la conoscenza della batteria e delle caratteristiche ambientali e le proprietà asimmetriche di un sistema sono utili per la progettazione di strategie di trasmissione / rilevamento.

The study aims to identify the reasons behind power shortages in the city Sulaymaniyah, located in northern Iraq or Iraqi Kurdistan, and to clarify how large the difference between power demand and supply is. Also, several interviews have been performed to give further insight to the issues and possibilities the region is facing. Nevertheless, a portion of the energy demand is met by local diesel generators supplying power in city districts. With the use of the software program ArcGIS, a mapping of all the diesel generators in the city districts is done in order to visualize the unsustainable conditions of the city. In addition, the energy output of the diesel generators is quantified, and the energy supplied to a household is estimated on an average. Later, calculations are performed to estimate the diesel generators price for electricity, their amount of annual CO 2 emissions and social costs. In order to bring light to renewable energy solutions, a solar PV configuration was chosen based on regulations and infrastructure issues in the region, suitable for households. Furthermore, with the use of intra-hour solar irradiance data from Meteonorm and the software Matlab, an optimal solar PV angle was calculated for Sulaymaniyah. Thereafter, the goal was to substitute diesel generated energy with solar PV energy and thus a solar PV system was estimated for a typical household based on; the average energy received from diesel generators, the solar PV system’s efficiency and the total solar irradiance striking the tilted panels. Furthermore, a Net Present Value was calculated to evaluate the economic profitability of the solar PV investment. Lastly, a sensitivity analysis was done with different scenarios to predict different outcomes of the NPV model. The study found that the energy system in Iraqi Kurdistan is unreliable and unsustainable, mostly due to infrastructure issues and political uncertainties. Due to these issues, power shortages occur on a daily basis and the difference between power supply and demand reached an average of 350 MW throughout 2018, and the largest difference reached 1304 MW. The number of diesel generators in the city was 525 and had a combined installed capacity of 176.6 MW, however they are usually working at 85 % operational efficiency resulting in a power supply of 150.1 MW. Additionally, it was estimated that a household receives an average of 920.07 W from the diesel generators. Furthermore, the calculated price for electricity was 207 IQD/kWh and all the generators combined pollutes approximately 319000 tons of CO 2 per year. The optimal angle for a solar panel in Sulaymaniyah was calculated to 21° and the recommended configuration for a solar PV system for households was a stand-alone battery storage system. In order for households to replace the diesel generators they need a capacity of 1.62 kW and a dimensioning of 9.66 m 2 . Finally, based on the NPV model it was found that it is economically profitable to invest in a solar PV system with today’s conditions. However, the investment is profitable with a relatively small margin and based on a scenario analysis, it showed that the investment might easily become unprofitable with the change of the discount rate. Lastly, it can be discussed that the actual demand in Sulaymaniyah is lower than the one presented, since it is artificial and very dependent on peoples consuming behaviors which might be different if they were to have access to electricity all the time. Also, one of the biggest obstacles that might hinder solar PVs to be integrated to the energy system is the net-metering, regulations and tariff issues. The KRG clearly does not give incentives to its people to invest in renewable energy, which also might be the reason why there is a very small market in Sulaymaniyah.

La energía es un elemento fundamental para muchos aspectos del desarrollo socioeconómico. Los servicios que la mayoría de las personas en los países industrializados dan garantizados - iluminación adecuada, energía limpia para calefacción y cocina, telecomunicaciones, fuerza motriz y ocio - están fuera del alcance en gran parte de la población mundial. La falta de acceso a servicios energéticos confiables y asequibles representa un claro obstáculo para el desarrollo humano, social, económico y para el logro de los Objetivos de Desarrollo del Milenio. Constituyendo actualmente un hecho inaceptable e insostenible, la pobreza energética representa una cruda realidad que junto a otros problemas globales debe ser tratada de manera urgente. A pesar de los importantes esfuerzos realizados por las instituciones y los gobiernos locales, las entidades públicas y las organizaciones internacionales, la tendencia indica que el número total de pobres en términos de acceso a la energía aumente en las próximas décadas, a menos de que se inicien de forma inmediata acciones adicionales orientadas a evitar ese incremento. En este sentido, la historia ha demostrado que es posible lograr un significativo avance en acceso energetico en un corto espacio de tiempo. Este hecho se ha producido recientemente en varios países asiáticos (por ejemplo, Vietnam), Sudáfrica y Brasil. Sin embargo, a pesar de los avances realizados en los países mencionados, las iniciativas que hoy en día se están desarrollando a nivel global para erradicar la pobreza energética no son suficientes en cuanto a su tamaño y alcance. Las estrategias relacionadas con la promoción del acceso a la energía para el desarrollo socioeconómico deben ir mucho más allá de la iluminación para hogares pobres. Los objetivos de dichas estrategias deberían estar orientados a generar cambios estructurales que originen un desarrollo sostenible. Además, la reciente crisis ha provocado retrocesos en el desarrollo sostenible de los países. La comunidad internacional tiene que adaptarse rápidamente a las nuevas circunstancias y proporcionar asesoramiento y asistencia que sea duradera en el tiempo y adaptable a cada caso, de cara a provocar un ambiente propicio para el desarrollo interno en los países. Hoy en día, no existen barreras técnicas que impidan suministrar servicios modernos de energía de forma segura, fiable y asequible a los miles de millones de pobres que no tienen acceso a la misma. Es nuestro deber contribuir a lograr la aspiración de los países más desfavorecidos para avanzar hacia economías sostenibles, y la energía es fundamental para esta transformación. Afortunadamente, el tema de acceso a la energía está recibiendo una atención cada vez mayor en todas las esferas. Como ejemplo ilustrativo de este hecho, el año 2012 ha sido declarado por la Asamblea General, el principal órgano normativo y representativo de las Naciones Unidas, como el Año Internacional de la Energía Sostenible para Todos. Es fundamental aprovechar este impulso, ya que la energía es necesaria para enfrentar muchos de los desafíos clave actuales. Así, abordar la pobreza energética de manera integral tendría enormes beneficios en diversas áreas relacionadas con el desarrollo de los países (por ejemplo, salud, educación, igualdad de género). Los capítulos de esta tesis persiguen conformar un conjunto coherente de piezas individuales de análisis en torno a un tema central: el nexo entre energía y el desarrollo socio-económico. Los diferentes capítulos están basados en artículos independientes y ofrecen perspectivas contrastadas y a la vez complementarias en relación al tema en cuestión. En definitiva, se trata de un ejercicio de investigación aplicada así como de desarrollo metodológico y el conjunto deriva en una evaluación integrada de las implicaciones de la energía para el desarrollo sostenible. La tesis está organizada de forma que se presente como una narrativa coherente y estructurada. En términos generales de su estructura, los primeros capítulos describen el problema de la pobreza energética, como la falta de acceso a servicios energéticos modernos. Estos capítulos ofrecen una idea de la magnitud del desafío que nos ocupa y presentan una evaluación de los escenarios posibles para lograr el acceso universal a la energía. En los capítulos siguientes, se presenta la escala de la inversión necesaria para abordar la cuestión así como intervenciones concretas que permitirían superar algunas de las cuestiones que se discuten. La Energía y los Objetivos de Desarrollo del Milenio Aunque intuitiva, la relación entre energía y desarrollo sostenible es difícil de determinar cuantitativamente y no ha sido explorada ni analizada en detalle en la literatura científica. La correlación entre el acceso a los servicios de energía y el desarrollo socioeconómico se refleja a menudo, por ejemplo, mediante el uso de índices compuestos como el Índice de Desarrollo Humano (HDI), o a partir de un análisis centrado únicamente en las repercusiones económicas. Este trabajo presenta una articulación estadística que analiza la relación entre la energía y varios elementos clave del desarrollo socioeconómico, utilizando los Objetivos de Desarrollo del Milenio como marco de referencia. Los resultados confirman la influencia potencialmente positiva que el acceso a los servicios de energía genera. La evaluación desarrollada en el trabajo proporciona una perspectiva basada en una serie de supuestos que a menudo se emplean alrededor de la correlación entre energía y desarrollo, y examina reivindicaciones de sus beneficios universalmente positivos a las prioridades específicas de desarrollo socioeconómico. Entre las conclusiones, se destaca que los beneficios para el desarrollo sostenible del acceso a los servicios de energía varían considerablemente. Medición de la pobreza energética Cualquier política que pretenda ser efectiva para expandir de forma considerable el acceso a energía moderna ha de estar fundamentada en una sólida base documental. Por lo tanto los análisis cuantitativos que se pueden utilizar con fines comparativos y de seguimiento de los avances hacia los objetivos planteados, representan una herramienta de apoyo esencial. Este trabajo revisa la literatura relevante en la materia, y analiza la idoneidad y la aplicabilidad de los instrumentos existentes para medir la pobreza energética. Basándose en esos instrumentos y en sus resultados, se propone un nuevo índice compuesto para medir la pobreza energética. Tanto la metodología como los resultados iniciales obtenidos de la aplicación del índice son presentados para varios países africanos. Mientras que la mayoría de los indicadores e índices compuestos existentes se centran en la evaluación del acceso a la energía o en el grado de desarrollo relacionado con la energía, el nuevo índice desarrollado - el Índice de Pobreza Multidimensional de la Energía (MEPI) - se centra en la privación del acceso a servicios energéticos modernos. Este índice, refleja la incidencia e intensidad de la pobreza energética y proporciona una nueva herramienta para la elaboración de políticas. Escenarios de acceso a la energía hasta el año 2030 para el África subsahariana Con el fin de alcanzar una meta de acceso universal a servicios modernos de energía para el año 2030, se han considerado varias opciones de desarrollo de sector eléctrico así como el hecho de informar consecuentemente a los políticos e inversionistas, de cara a orientar de forma adecuada el diseño del sistema. Con este fin, y basándose en las herramientas y análisis existentes, se presentan varios escenarios de forma transparente y para toda la economía del sector energético de África subsahariana hasta el año 2030. Estos escenarios se han elaborado teniendo en cuenta el contexto de las tendencias históricas y las diversas interpretaciones sobre el concepto de acceso universal a la energía. Los mismos, están diseñados para proporcionar una indicación de la escala general en relación al esfuerzo requerido por la comunidad internacional. Actualmente, la mayoría de las proyecciones con métodos tradicionales de predicción a largo plazo en materia de planificación energética muestran un aumento de aproximadamente tres veces la capacidad de generación instalada para el año 2030, pero probablemente se requiera que ese aumento sea de más de diez veces, si se pretende proporcionar un acceso completo a nivel global - incluso a niveles relativamente modestos de consumo de electricidad. Esto equivale a aproximadamente un 13% la tasa media de crecimiento anual, en comparación con un histórico (en las últimas dos décadas) de 1,7%. Escala de la inversión para el acceso a la energía universal Para ayudar a proporcionar una mayor claridad y apoyo a la toma de decisiones políticas, así como en el diseño de propuestas financieras, en este trabajo es considerado y analizado el nivel global de gasto requerido para satisfacer el acceso universal a servicios de energía modernos. Este trabajo revisa la literatura existente a nivel mundial, regional, nacional y de proyecto, y a su vez se realiza un desglose de las estimaciones de costos necesarios, a fin de proporcionar una mayor transparencia a través del desarrollo de indicadores comparables. Con la nueva metodología desarrollada, calculamos tres escenarios de costos nuevos que intentan abordar varias deficiencias analíticas existentes. Como conclusión, el costo total de proporcionar (de forma aproximada) el acceso universal se espera que probablemente sea considerablemente más alto que las estimaciones publicadas, que a menudo se centran principalmente en los costos de capital. Si bien se reconoce la naturaleza aproximada de los análisis, el costo anual del acceso universal a la electricidad y energía limpia para la cocinar se calcula que va desde USD 14 a 136 mil millones (de USD 12 a 134 mil millones para electrificación y de USD 1,4 a 2,2 mil millones para energía limpia para la cocinar). Actuales flujos financieros relacionados con el acceso a la energía De cara a contribuir al diseño de políticas apropiadas y eficaces para reducir la pobreza energética, este análisis presenta una evaluación de los flujos macro financieros actuales en el sector eléctrico y de distribución de gas en los países en desarrollo. Se basa en la metodología más extendida actualmente para cuantificar los flujos de inversión en el área de cambio climático. El enfoque se centra en las variables de formación bruta de capital fijo nacional, la ayuda al desarrollo procedente del extranjero y la inversión extranjera directa. Estas cifras proporcionan a los responsables políticos una idea de la escala de inversión necesaria, aunque esto representan sólo una pequeña parte de la información necesaria para diseñar los instrumentos financieros requeridos para lograr el acceso universal a la energía. Igualmente, estas cifras tienden a ocultar muchas variaciones entre sectores y países, así como las tendencias y otras fluctuaciones en el tiempo. En cualquier caso, se puede concluir que la corriente de inversión destinada a los países más pobres se queda muy corta (por lo menos cinco veces) si se pretende proporcionar un nivel básico de acceso a servicios modernos de energía limpia a los ‘pobres energéticos’. Mecanismo de Desarrollo Limpio y el Desarrollo Sostenible El Mecanismo de Desarrollo Limpio (MDL) tiene un doble objetivo: compensar las emisiones de gases de efecto invernadero y contribuir al desarrollo sostenible en el país anfitrión, aunque la contribución a este último objetivo parece marginal en la mayoría de las actividades del MDL. Además, las actividades del MDL están distribuidas de forma desigual entre los países en desarrollo. En respuesta a estas inquietudes, se han puesto en marcha varias iniciativas cuyo objetivo es la promoción de proyectos MDL que generen amplios dividendos orientados al desarrollo local sostenible, como el Gold Standard y el Community Development Carbon Fund (CDCF). La certificación Gold Standard recompensa las mejores prácticas de proyectos MDL, mientras que el CDCF se centra en la promoción de las actividades del MDL en comunidades desfavorecidas. A partir de un método de criterios múltiples, este trabajo analiza, la contribución potencial al desarrollo local sostenible de los proyectos del MDL, comparando los proyectos que tienen atributos particulares con los proyectos ordinarios. Los resultados obtenidos sugieren que generalmente aunque no siempre, los proyectos MDL con certificación, tienden a superar ligeramente a los proyectos similares sin certificación en términos de beneficios a nivel local.
Energy is central to many aspects of socio-economic emancipation. The services that most people in industrialised countries take from granted – adequate lighting, low-polluting heating and cooking energy, telecommunication and entertainment, motive power – are out of reach to large parts of the world’s population. A lack of access to affordable and reliable energy services represents a key obstacle to human, social, and economic development and the achievement of the Millennium Development Goals. As unacceptable and unsustainable as it is, widespread energy poverty represents a stark reality which must be dealt alongside other pressing global issues. Despite the significant efforts by local institutions and governments, utilities and international organisations, the absolute number of energy poor is expected to rise in coming decades in the absence of additional dedicated action. History has shown, however, that significant progress can be achieved with regard to improving energy access in a short timeframe. Remarkable improvements occurred rapidly in several Asian countries (e.g. Vietnam), South Africa and Brazil in the recent past. However, current initiatives to eradicate energy poverty are insufficient in scale and scope, and attempting to address the issue in the same incremental fashion as in the past is clearly inappropriate. Energy for development strategies must go well beyond merely providing light to poor households. They should aim at transformative changes that bring about sustainable development. The recent succession of crises has set back some development progress. The international community needs to adjust swiftly to the new circumstances and provide advice and assistance that is resilient and long-lasting, and creates an environment that is conducive to enhancing endogenous development. Today, there is no technical barrier to providing the billions of energy poor with modern, safe, reliable and affordable energy services. It is our duty to deal with the aspiration of countries to move towards modern economies, and energy is paramount to such transformation. Fortunately, the issue of energy access is receiving greater and greater attention. As an illustrative example, 2012 has been declared by the General Assembly, the main deliberative, policymaking and representative organ of the United Nations, as the International Year of Sustainable Energy for All. It is crucial to capitalise on this momentum, as energy is central to facing many of today's key development challenges. Addressing the issue of energy poverty in a comprehensive manner would have enormous multiple benefits (e.g. health, education, gender equality). The various chapters of this thesis form a coherent ensemble of individual pieces of analysis around a core topic, namely the nexus between energy and socio-economic development. The different chapters, which are based on stand-alone articles, provide contrasting and complementary perspectives around the issue at hand. It consists of applied research as well as methodological development, and forms altogether an integrated assessment of energy for sustainable development. The thesis is organised in such a way so as to present a consistent and structured narrative. In terms of broad structure, the first chapters gauge the issue of energy poverty, or the lack of access to modern energy services. They offer a sense of the magnitude of the challenge at hand, as well as present an assessment of scenarios towards universal energy access. This is followed by insights on the scale of investment required to address the issue. Finally, concrete interventions to overcome some of the issues are discussed. Energy and the Millennium Development Goals While intuitive, the relationship between energy and development is difficult to quantitatively ascertain and has not been analytically explored in detail in the scientific literature. The correlation between access to energy services and development is, however, often addressed in aggregate in the literature, for example by using composite indexes such as the Human Development Index (HDI), or by focusing strictly on economic impacts. This analysis presents a statistical articulation of the link between energy and various proxies of development, using the Millennium Development Goals as a framework. The outcomes confirm the potentially positive influence of access to energy services on development. The assessment provides a perspective on a number of often employed assumptions about the correlation between energy and development, and challenges claims of its universally positive benefits to specific development priorities. It is found that the benefits to development of access to energy services vary considerably. Measuring Energy Poverty Effective policies to dramatically expand modern energy access need to be grounded in a robust information-base. Metrics that can be used for comparative purposes and to track progress towards targets therefore represent an essential support tool. This analysis reviews the relevant literature, and discusses the adequacy and applicability of existing instruments to measure energy poverty. Drawing on those insights, it proposes a new composite index to measure energy poverty. Both the associated methodology and initial results for several African countries are discussed. Whereas most existing indicators and composite indices focus on assessing the access to energy, or the degree of development related to energy, the new index developed – the Multidimensional Energy Poverty Index (MEPI) – focuses on the deprivation of access to modern energy services. It captures both the incidence and intensity of energy poverty, and provides a new tool to support policy-making. Energy Access Scenarios to 2030 for sub-Saharan Africa In order to reach a goal of universal access to modern energy services by 2030, consideration of various electricity sector pathways is required to help inform policy-makers and investors, and help guide power system design. To that end, and building on existing tools and analysis, several ‘high-level’, transparent, and economy-wide scenarios for the sub-Saharan African power sector to 2030 are presented. These simple scenarios are constructed against the backdrop of historical trends and various interpretations of universal access. They are designed to provide the international community with an indication of the overall scale of the effort required. Most existing projections, using typical long-term forecasting methods for power planning, show roughly a threefold increase in installed generation capacity occurring by 2030, but more than a tenfold increase would likely be required to provide for full access – even at relatively modest levels of electricity consumption. This equates to approximately a 13% average annual growth rate, compared to a historical one (in the last two decades) of 1.7%. Scale of Investment for Universal Energy Access To help provide clarity, support political decision making, and inform the design of financial responses, the overall scale of spending required to meet universal access to modern energy services is considered. The existing literature at the global, regional, national, and project levels and disaggregate cost estimates is reviewed in order to provide increased transparency through comparable metrics. A new methodology is developed to calculate three new cost scenarios that attempt to address several existing analytical gaps. As a conclusion, the total cost of providing (near) universal access is expected to be likely considerably higher than published estimates which often focus primarily on capital costs. While recognizing the coarse nature of the analysis, the annual cost of universal access to electricity and clean cooking is estimated at ranging from USD 14 to 136 billion (USD 12 - 134 billion for electrification and USD 1.4 to 2.2 billion for clean cooking) depending on the various scenarios and assumptions. Current Financial Flows related to Energy Access To help inform the design of appropriate and effective policies to reduce energy poverty, this analysis presents an assessment of the current macro financial flows in the electricity and gas distribution sectors in developing countries. It builds on the methodology used to quantify the flows of investment in the climate change area. The approach relies on national gross fixed capital formation, overseas development assistance, and foreign direct investment. These high-level and aggregated investment figures provide a sense of the scale to policy-makers, but are only a small part of the information required to design financial vehicles. In addition, these figures tend to mask numerous variations between sectors and countries, as well as trends and other temporal fluctuations. Nonetheless, for the poorest countries, one can conclude that the current flows are considerably short (at least five times) of what will be required to provide a basic level of access to clean, modern energy services to the ‘energy poor’. Clean Development Mechanism and Sustainable Development The Clean Development Mechanism (CDM) has a twofold objective, to offset greenhouse gas emissions and to contribute to sustainable development in the host country. The contribution to the latter objective seems marginal in most CDM activities. Also, CDM activities are unevenly spread among developing countries. In response to these concerns, initiatives with the objective of promoting CDM projects with broad local sustainable development dividends have been launched, such as the Gold Standard and the Community Development Carbon Fund. The Gold Standard label rewards best-practice CDM projects while the Community Development Carbon Fund focuses on promoting CDM activities in underprivileged communities. Using a multi-criteria method, the potential contribution to local sustainable development of those CDM projects with particular attributes is compared with ordinary ones. This evaluation suggests that labelled CDM activities tend to slightly outperform comparable projects, although not unequivocally.

Modern energy services are a foundation for sustainable development. As recently acknowledged by the multilaterally supported UNDP’s ‘energy access for all’ objective, it is a missing cog for the socio-economic, empowerment, livelihood enhancement and sustainability of more than 2 billion people in developing and less developed countries. Efforts to provide modern energy services, however, face pervasive challenges reflective of wider development efforts, establishing the imperative for greater understanding of their underlying dimensions as a basis for enhancing sustainable development pathways. The thesis pursues this through ethnographic studies of innovative and contrasting energy access pathways in remote areas of Nepal. These were supported by preliminary site visits, semi-structured interviews, participant observation and observant participation with a range of key development actors, led by a reflexive, multi-sited research approach. The research reveals that the challenges and opportunities of effective energy access and sustainable development are embedded in under-recognised social routines and contexts that subsume essential dimensions of daily life. These are dynamic, multi-actor and interconnected through routinised codes, performances and institutions for which social emotions, meanings and relations are integral. Interventions, technologies and impacts interdepend on these mundane interactions and structures, signifying the vital role of social agency and conventions in everyday life. ‘Access’ is a constant (re)negotiation of these within a socio-technical context. The findings demonstrate the value of integrating these dimensions into development approaches through being attentive to, and co-produced by, the plurality of actors, settings and routines. A practice theory informed approach supported the analysis to signify further distinctive policy, research and pathway implications. The thesis thus demonstrates the potential of a social practice approach for enabling a more sensitive and effective framework for enabling energy access for sustainable development.

The closed greenhouse is an innovative concept in sustainable energy management. The closed greenhouse can be considered as a large commercial solar building. In principle, it is designed to maximize the utilization of solar energy through seasonal storage. In a fully closed greenhouse, there are not any ventilation windows. Therefore, the excess sensible and latent heat must be removed, and can be stored using seasonal and/or daily thermal storage technology. The available stored excess heat can be utilized later in order to satisfy the heating demand in the greenhouse, and also in neighbouring buildings. A model for energy analysis of a greenhouse has been developed using the commercial software TRNSYS. With this model, the performance of various design scenarios has been examined. The closed greenhouse is compared with a conventional greenhouse using a case study to guide the energy analysis. In the semi-closed greenhouse, a large part of the available excess heat will be stored through thermal energy storage system (TES). However, a ventilation system can still be integrated in order to use fresh air as a rapid response indoor climate control system. The partly closed greenhouse consists of a fully closed section and a conventional section. The fully closed section will supply the heating and cooling demand of the conventional section as well as its own demand. The results show that there is a large difference in heating demand between the ideal closed and conventional greenhouse configurations. Also, it can be concluded that the greenhouse glazing type (single or double glass) and, in the case of the semi-closed and partly closed greenhouse, the controlled ventilation ratio are important for the thermal energy performance of the system.  A thermo-economic analysis has been done in order to investigate the cost feasibility of various closed greenhouse configurations. From this analysis, it was found that the load chosen for the design of the seasonal storage has the main impact on the payback period. In the case of the base load being chosen as the design load, the payback period for the ideal closed greenhouse might be reduced by 50% as compared to using peak load. Thus, future studies should explore innovative combinations of short term and seasonal storage. Finally, several energy management scenarios have been discussed in order to find alternatives for improving the energy performance of the closed greenhouses. However, no specific optimal solution has so far been defined.

QC 20111115

This research aims at exploring meanings, qualities and analytical abilities of density concept and its potential interpretations in architecture and sustainability fields. Despite the growing unsustainability of today's city facing an effective energy and environmental crisis, recent statistics have confirmed the increasing attractive power of metropolitan areas. Within the context of European compact city, new building models based on energy conservation principles account for an insignificant percentage compared to the great mass of existing city whose functioning remarkably affects the inefficiency of the whole metropolitan system. Therefore an approach determining design instruments and methods at urban and architectural scale must be found in order to set out conditions more appropriate to the compact city. At this analysis stage, the relationship between energy and form takes a central role in the variation of energy performances; at the same time the concept of density has showed the ability to describe the morphological performances of the built form. The general aim of the present research is to determine the relationships among built-form, energy and urban fabrics by the density parameter in compact city with Mediterranean climate. This research is composed by four interconnected parts. The first one examines the relationship among current urban and energy dynamics to comprehend the role and contribution of the building industry in the light of the scientific progress and the implementation of present operational and regulatory instruments. The second one investigates role and evolution of the density concept as parameter, design instrument and basis of theoretical categories, especially referring to interactions with urban form and sustainability. In the third part the analytical and interpretative abilities of density are employed in order to prove the environmental implications and verify the existence of interactions among urban sustainability indicators and density. Finally, the fourth part enquires into the relationships among form, building, density and energy set up in the compact fabrics in Rome and Barcelona by models and simulations in order to control the main formal, building and energy factors parametrically. The influence of urban morphology, built-form and constructive features on solar access and energy demand for conditioning are shown by different density indicators that are the more suitable to express reliable trends. Firstly results point out that the contribution of the built environment to the complex energy issue arisen by metropolitan systems must be focused on the reduction of the demand - even before on the consumption and impact - operating with multi-scale instruments and methods for the transformation of existing city. The density has a preferred role in the relationship between sustainability and form thanks to its interpretative skills and meanings undertaken as theoretical and design category. At the metropolitan scale, urban quality indicators and density do not always show evident relationships with energy and environmental implications. Built-form typology and constructive features are the main factors that occur on energy performances variation of urban fabrics. The investigation of these kind of performances by density parameters leads to the comprehension of the different energy behavior in each urban texture, offering a contribution to the energy analysis at urban scale. Methodology and the defined parameters of density show themselves as knowledge base for aware transformations of Mediterranean compact city as well as applications in other urban contexts both for existing and new constructions.
La ricerca esplora significati, proprietà e capacità analitiche del concetto di densità e delle sue possibili interpretazioni nell’ambito dell’architettura e della sostenibilità. Il suo obiettivo è la determinazione di relazioni tra costruito, energia e forma dei tessuti urbani della città compatta mediterranea ricorrendo alla densità quale parametro utile a decifrarne le specificità. A dispetto della sempre maggiore insostenibilità della città odierna, di fronte alla crisi energetica ed ambientale in atto, recenti statistiche hanno confermato il crescente potere attrattivo delle aree metropolitane. Nel contesto della città compatta europea, i nuovi modelli insediativi basati su principi di risparmio energetico rappresentano una percentuale insignificante rispetto alla città esistente che, nel funzionare, incide notevolmente sull’inefficienza dell’intero sistema metropolitano. In questo quadro, potrebbe essere risolutivo identificare un approccio che individui strumenti e metodi progettuali alla scala urbana piuttosto che a quella architettonica, utili a definire condizioni più appropriate e realmente incisivi per la città compatta. Se riferito in primo luogo a tale scala il rapporto tra energia e forma assume un ruolo centrale sulla variazione delle prestazioni energetiche; allo stesso tempo il concetto di densità appare un’efficace strumento di analisi delle prestazioni morfologiche del costruito. La ricerca si compone di cinque parti. La prima analizza la condizione odierna delle dinamiche urbane ed energetiche, per comprendere ruolo e contributo dell’edilizia alla luce dell’avanzamento del pensiero scientifico e degli strumenti operativi disponibili. La seconda affronta il significato e l’evoluzione del concetto di densità quale parametro di misura, strumento progettuale e fondamento teorico, facendo riferimento in particolare alle interazioni con la forma urbana e la sostenibilità. Nella terza si utilizzano le capacità analitiche della densità per comprovare le implicazioni ambientali e verificare l’esistenza di leggi di dipendenza tra indicatori di sostenibilità urbana e densità. La quarta pone le basi per la comprensione delle relazioni tra densità ed energia alla scala urbana. La quinta parte, infine, indaga tali relazioni nei tessuti compatti di Roma e Barcellona declinandole in termini di caratteri formali e costruttivi, con l’ausilio di modellazioni e simulazioni strutturate allo scopo di controllare i corrispondenti fattori. S’illustra l’influenza di morfologia urbana e caratteri tipologico-costruttivi su guadagno solare e domanda energetica per riscaldamento e climatizzazione, individuando per mezzo di differenti definizioni d’indicatori di densità, i più adeguati ad esprimere con queste leggi di variazione affidabili. I risultati evidenziano che il contributo dell’edilizia alla complessa questione energetica posta dai sistemi metropolitani deve concentrarsi sulla riduzione della domanda - ancor prima che su consumo e impatto - operando con strumenti e metodi interscalari per la trasformazione della città esistente. La densità ha un ruolo privilegiato nel rapporto forma-sostenibilità per capacità interpretative e significati assunti quale categoria teorica e progettuale. A scala metropolitana, indicatori di sostenibilità urbana e densità non sempre mostrano chiare relazioni con le implicazioni ambientali ed energetiche. Morfologia, tipologia e aspetti costruttivi sono i fattori che più intervengono sulla variazione delle prestazioni energetiche dei tessuti urbani. Analizzarli mediante parametri di densità conduce alla comprensione del diverso comportamento energetico, fornendo un contributo agli strumenti d’indagine a scala urbana e favorendo una connotazione più efficiente del costruito riconducibile alla dimensione della densità sostenibile. Il metodo e gli strumenti individuati si offrono come base di conoscenza per trasformazioni consapevoli della città compatta mediterranea
El presente estudio indaga significados, propiedad y capacidad analíticas del concepto de densidad y de su posible interpretación en el ámbito de la arquitectura y de la sostenibilidad. El principal objetivo es determinar las relaciones entre ambiente construido, energía y forma de los tejidos urbanos recurriendo a la densidad como parámetro útil para descifrar sus especificidades de la ciudad compacta mediterránea. A pesar de una siempre mayor insostenibilidad de la ciudad actual, frente a la crisis energética y ambiental en curso, estadísticas recientes han confirmado el creciente poder atractivo de las metrópolis. En el contexto de la ciudad europea, los modelos de asentamiento actuales, basados en principios de ahorro energético, constituyen un porcentaje insignificante frente a la ciudad existente que, funcionando, grava notablemente en consumo el sistema metropolitano. En esta situación, podría ser resolutivo identificar un acercamiento que identifique herramientas y métodos para el proyecto a escala urbana, que sean útiles para definir condiciones más apropiadas y sean realmente eficaces para la ciudad compacta. Si se refiere en primer lugar a dicha escala, la relación entre energía y forma asume una función central para la variabilidad de la prestación energética; al mismo tiempo el concepto de densidad parece una herramienta eficaz para analizar las prestaciones morfológicas del ambiente construido. La investigación se compone de cinco partes. La primera analiza las dinámicas urbanas y energéticas actuales, para entender capacidad y contribución de la construcción a la luz del avance del pensamiento científico y de las herramientas disponibles. La segunda trata el significado y la evolución del concepto de densidad como parámetro de medida, herramienta del proyecto y origen teórico de la arquitectura, con particular referencia a las interacciones con la forma urbana y la sostenibilidad. En la tercera se utilizan las capacidades analíticas de la densidad para comprobar las repercusiones ambientales y verificar la existencia de leyes de dependencia entre indicadores de sostenibilidad urbana y densidad. La cuarta explica las relaciones entre densidad y energía a la escala urbana. La quinta, finalmente, estudia estas relaciones en los tejidos compactos de Roma y Barcelona, explicándolas en función de forma i construcción, con el auxilio de modelos y simulaciones. Se muestra la influencia de la morfología urbana y las características tipológicas y constructivas sobre la captación solar y la demanda energética por calefacción y climatización, individualizando entre diferentes indicadores de densidad los más apropiados para representar tendencias fiables. Los resultados prueban que la contribución de la construcción a la compleja cuestión energética tiene que basarse en la reducción de la demanda - antes que del consumo y del impacto - utilizando herramientas y métodos multi-escalares para la transformación de la ciudad existente. La densidad tiene una función privilegiada en la relación forma-sostenibilidad que depende de sus capacidades analíticas y significados en calidad de categoría teórica y del proyecto. A escala metropolitana, los indicadores de sostenibilidad urbana y densidad no siempre muestran una relación clara con las repercusiones ambientales y energéticas. Morfología, tipología y aspectos constructivos son los factores que más influyen sobre la variación de la prestación energética de los tejidos urbanos. Analizarlos recurriendo a parámetros de densidad, lleva a entender el diferente comportamiento energético, contribuye a las investigaciones a escala urbana y favorece la eficiencia del ambiente construido, con lo cual se reconduce el análisis al concepto de densidad sostenible. La metodología y las herramientas individualizadas se ofrecen como base de conocimiento para orientar las transformaciones de la ciudad compacta mediterránea.

The need to reduce humankind reliance on fossil fuels by exploiting sustainably the planet renewable resources is a major driving force determining the focus of modern material research. For this reason great interest is nowadays focused on finding alternatives to fossil fuels derived products/materials. For the short term the most promising substitute is undoubtedly biomass, since it is the only renewable and sustainable alternative to fossil fuels as carbon source. As a consequence efforts, aimed at finding new synthetic approaches to convert biomass and its derivatives into carbon-based materials, are constantly increasing. In this regard, hydrothermal carbonisation (HTC) has shown to be an effective means of conversion of biomass-derived precursors into functional carbon materials. However the attempts to convert raw biomass, in particular lignocellulosic one, directly into such products have certainly been rarer. Unlocking the direct use of these raw materials as carbon precursors would definitely be beneficial in terms of HTC sustainability. For this reason, in this thesis the HTC of carbohydrate and protein-rich biomass was systematically investigated, in order to obtain more insights on the potentials of this thermochemical processing technique in relation to the production of functional carbon materials from crude biomass. First a detailed investigation on the HTC conversion mechanism of lignocellulosic biomass and its single components (i.e. cellulose, lignin) was developed based on a comparison with glucose HTC, which was adopted as a reference model. In the glucose case it was demonstrated that varying the HTC temperature allowed tuning the chemical structure of the synthesised carbon materials from a highly cross-linked furan-based structure (T = 180oC) to a carbon framework composed of polyaromatic arene-like domains. When cellulose or lignocellulosic biomass was used as carbon precursor, the furan rich structure could not be isolated at any of the investigated processing conditions. These evidences were indicative of a different HTC conversion mechanism for cellulose, involving reactions that are commonly observed during pyrolytic processes. The evolution of glucose-derived HTC carbon chemical structure upon pyrolysis was also investigated. These studies revealed that upon heat treatment (Investigated temperatures 350 – 900 oC) the furan-based structure was progressively converted into highly curved aromatic pre-graphenic domains. This thermal degradation process was observed to produce an increasingly more hydrophobic surface and considerable microporosity within the HTC carbon structure. In order to introduce porosity in the HTC carbons derived from lignocellulosic biomass, KOH chemical activation was investigated as an HTC post-synthesis functionalisation step. These studies demonstrated that HTC carbons are excellent precursors for the production of highly microporous activated carbons (ACs) and that the porosity development upon KOH chemical activation is dependent on the chemical structure of the HTC carbon, tuned by employing different HTC temperatures. Preliminary testing of the ACs for CO2 capture or high pressure CH4 storage yielded very promising results, since the measured uptakes of both adsorbates (i.e. CO2 and CH4) were comparable to top-performing and commercially available adsorbents, usually employed for these end-applications. The combined use of HTC and KOH chemical activation was also employed to produce highly microporous N-doped ACs from microalgae. The hydrothermal treatment of the microalgae substrate was observed to cause the depletion of the protein and carbohydrate fractions and the near complete loss (i.e. 90%) of the microalgae N-content, as liquid hydrolysis/degradation products. The obtained carbonaceous product showed a predominantly aliphatic character indicating the presence of alkyl chains presumably derived from the lipid fractions. Addition of glucose to the initial reaction mixture was found out to be extremely beneficial, because it allowed the fixation of a higher N amount, in the algae derived HTC carbons (i.e.  60%), and the attainment of higher product yields (50%). Both positive effects were attributed to Maillard type cascade reactions taking place between the monosaccharides and the microalgae derived liquid hydrolysis/degradation products, which were in this way recovered from the liquid phase. KOH chemical activation of the microalgae/glucose mixture derived HTC carbons produced highly microporous N-doped carbons. Although the activation process led to a major reduction of the N-content, the retained N-amount in the ACs was still considerable. These features render these materials ideal candidates for supercapacitors electrodes, since they provide extremely high surface areas, for the formation of electric double-layer, coupled to abundant heteroatom doping (i.e. N and O) necessary to obtain a pseudocapacitance contribution.
Die Notwendigkeit, die Abhängigkeit der Menschheit von fossilen Brennstoffen zu reduzieren ist die treibende Kraft hinter aktuellen Forschungsanstrengungen in den Materialwissenschaften. Folglich besteht heutzutage ein erhebliches Interesse daran Alternativen zu Materialien, die aus fossilen Resourcen gewonnen werden, zu finden. Kurzfristig ist zweifellos Biomasse die vielversprechendste Alternative, da sie aus heutiger Sicht die einzige nicht-fossile, nachhaltige und nachwachsende Kohlenstoffquelle ist. Konsequenterweise werden die Antrengungen neue Syntheseansätze zur Konvertierung von Biomasse und ihren Derivaten in kohlenstoffbasierten Materialien forwährend erhöht. In diesem Zusammenhang hat sich die Hydrothermalkarbonisierung (HTC) als sehr vielseitiges Werkzeug zur Konvertierung von Biomasse-basierten Ausgangsstoffen in funktionale Kohlenstoffmaterialien herausgestellt. Dennoch gibt es bisher wenige Ansätze um rohe Biomasse, genauer gesagt Lignicellulose, direkt in funktionale Materialien umzusetzen. Könnte der direkte Einsatz von roher Biomasse Verfahren wie der HTC zugänglich gemacht werden, würde dies die Nachhaltigkeit des Verfahrens immens steigern. Daher wurde in dieser Dissertation die Hydrothermalkarbonisierung von kohlenhydratreicher (d. h. Lignicelluse) und proteinreicher (d. h. Microalgae) Biomasse systematisch analysiert. Diese Untersuchung galt dem Ziel einen besseren Einblick in das Potential dieser thermochemischen Verarbeitungsmethode funktionale Kohlenstoffmaterialien aus unverarbeiteter Biomasse hervorzubringen zu gewinnen. Die hergestellten Materialien wurden mittels chemischer Aktivierung nachträglich weiter behandelt. Dieser zusätzliche Verarbeitungsschritt ermöglichte die Herstellung hochporöser aktiverter Kohlenstoffe (AC). Die aus Lignicellulose gewonnenen ACs zeigten exzellente Eigenschaften bei der Aufnahme von CO2 und der Hochdruckspeicherung von CH4 währen die aus Microalgae gewonnen Eigenschaften an den Tag legten (z. B. hohe Oberfläche und N-Dotierung), welche sie zu vielversprechenden Materialien für Superkondensatoren machen. Die in dieser Dissertation präsentierte Arbeit zeigte außergewöhnliche Fortschritte in Richtung der Anwendung von unbehandelter Biomasse als Ausgangsmaterial für die Produktion von funktionalen Kohlenstoffen.

Ethiopia is a nation endowed with huge amount of water, wind, solar and geothermal energy potentials.However, regardless of its enormous potentials the energy system is highly dependent on traditional fossilfuels and biomass and only about 32% of the nation‟s population has access to electricity. Given this fact,the country has engaged itself in unprecedented multimillion dollar energy projects in recent years.However, some of the projects and the construction of huge dams have raised controversy oversustainability issues. In this thesis work, the potentials and opportunities of the Ethiopian energy systemsand the sustainability of the ongoing and planned energy projects are discussed. Their social,environmental and economic implications are also addressed based on an in depth literature review. Asurvey was also conducted through questionnaire to research people‟s opinion on the current projects andtheir implications and results were interpreted using Web HIPRE software. It is concluded that thesurveyed group, selected and contacted randomly, believe that the economy is the most important aspectfor the country to consider giving it a weight of 43% over the social (29%) and environmental (28%)aspects. The Web HIPRE analysis also showed that respondents support the current hydropower projectson the Gibe River. Different important stakeholder such as farmers, fishermen and other inhabitants of thearea who are directly affected (positively or negatively) by the projects and also people from EEPCo andother concerned bodies such as policy makers are not included in this survey due to communicationproblems to gather data. The inclusion of data from such key stakeholder could have potentially changedthe outcome of the survey. It is also concluded that while there are lots of rooms for improvements on theprojects (prior and post construction), some of the criticisms encircling the project seem to lack allrounded understanding of the social and economic needs of the country as well as the long term ecosystemimplications of the projects. It is also concluded that Ethiopia, if it uses its energy potentials properly,could not only meet its energy demands but also be a giant energy supplier to east African nations in a few years.

This dissertation seeks to contribute to the policy discussion on how to design efficient and sustainable energy policies. In three self-contained chapters, it applies microeconomic theory and empirical analysis to identify three market failures in European energy markets and to evaluate specific policy measures that strive to overcome these failures in order to increase market efficiency and to enhance environmental or societal sustainability. Chapter 1 and 2 study European electricity markets, which play an important role in the transition towards a carbon-neutral energy future. Overcoming barriers to efficient electricity markets is a crucial step to keep the costs of this transition as low as possible to society. Both chapters focus on obstacles to electricity market efficiency that have recently been highlighted by the European Commission. On the supply side, subsidies for renewable electricity may distort production incentives and competition in wholesale electricity markets. Chapter 1 applies a theoretical model to study the effect of different subsidies on producer strategies and competition in wholesale electricity markets. On the demand side, the European Commission seeks to overcome the reluctance of residential electricity consumers to switch electricity supplier in order to ensure effective competition in the retail electricity market. Chapter 2 empirically quantifies different reasons for switching inertia using a structural discrete choice model and performs counterfactual analysis to study the effect of different policy measures that seek to overcome switching inertia. Chapter 3 looks at the building sector, which accounts for 40% of final energy consumption in Europe and is a major emitter of carbon emissions. In the residential housing market information asymmetries hamper incentives to invest in energy efficiency improvements of rental property. This chapter empirically analyzes the effect of a European policy that mandates the use of energy performance certificates aiming at establishing an efficient market for energy efficient dwellings.
Doctorat en Sciences économiques et de gestion
info:eu-repo/semantics/nonPublished

Thesis (Master of Architecture)--University of Cincinnati, 2008.
Committee/Advisors: Tom Bible (Committee Chair), Elizabeth Riorden (Committee Co-Chair), Gerald Larson (Advisor). Title from electronic theses title page (viewed Sep. 2, 2008). Includes abstract. Keywords: Sustainable; Energy; Renewable; Skyscraper. Includes bibliographical references.

This dissertation explores catalyst technology for the production of renewable liquid fuels via thermo-chemical conversion of biomass derived syngas. Fischer-Tropsch synthesis is a process for converting syngas, i.e. a mixture of CO and H2, into energy rich long chain hydrocarbons and oxygenated compounds. This synthesis process involves a number of elementary reactions leading to an array of polymeric products. The economic operation of an FTS process lie in the interplay of both catalyst and reactor design. In relation to catalysis, the nature of chemisorbed species, and the fractional availability of active metal sites determines rate, conversion and yield. Similarly, reactor design decides the operational envelope and determines the economics of an FTS process. Eggshell cobalt catalysts are used in CO hydrogenation reactions due to their ability to maximize the use of precious cobalt metal. The thickness of the shell can be utilized to control the product yield and distribution. In this study, during catalyst synthesis stage, metal-support interaction has been exploited to control the thickness and hence, the product distribution. The catalysts are prepared using precipitation of cobalt nitrate (dissolved in ethanol) on silica support. The metal deposition rate and the location are controlled through optimized non-polar solvent imbibing, followed by water addition to a Co(NO3)2-ethanol solution and hydrolysis by urea. The eggshell coating thickness (in the absence of restricting solvent) onto silica gel substrate was modeled via theoretical equations and experimentally verified during catalyst preparation through microscopic analysis of catalyst samples. Bulk precursor solution properties such as viscosity and surface tension along with substrate properties such as tortuosity are analyzed and included in the theoretical analysis for tailoring the catalyst eggshell thickness. Polar and non-polar solvent interactions with silica gel are exploited during cobalt precipitation to control the eggshell thickness. The catalyst samples were characterized using hydrogen chemisorption studies. The catalyst was tested in a fixed bed tubular bench scale reactor using research grade synthetic feed gases (H2:CO being 2:1). Products were analyzed in a GC column fitted with flame ionized detector and the results were compared with Anderson-Schulz-Flory distribution. Liquid product analysis validated the approach used for eggshell catalyst design and synthesis. The impact of solvent and calcination conditions, on the performance of eggshell catalysts was examined. Solvents such as water and alcohol attach to the silanol groups on the silica gel surface and compete with metal salts during ion exchange and adsorption. The solution properties impact metal dispersion and interaction with metal support. The calcination conditions (static versus dynamic, oxidizing versus reducing atmosphere) also have an impact on metal dispersion and support interaction. Ethanol proved to be a better solvent for enhancing the dispersion due to its surface wetting properties. Direct reduction in dynamic hydrogen provided gradual decomposition of the cobalt precursor thus reducing agglomeration. Both the use of water as a solvent and a static air environment during calcination led to lower dispersion. The back reaction of calcination products (especially H2O) and agglomeration due to thermal expansion were competing phenomenon in a static oxidizing environment. Catalyst characterization revealed that the latter effect was pre-dominant. Catalyst performance testing was first done with pure gases (H2 & CO) in a fixed bed reactor. Additionally, to examine the technological feasibility and economic viability of producing liquid fuels from biomass via the thermo-chemical route, laboratory scale testing was done using syngas produced by gasification of pine chips. The pine chips were gasified in a tubular entrained flow gasifier operated at MSU and supplied in cylinders. The raw biomass syngas was treated using a series of adsorbents to remove tar, water and other impurities. This pre-treated gas was subjected to Fischer-Tropsch Synthesis (FTS) in a bench scale fixed bed reactor using the eggshell cobalt catalyst developed in our laboratory. Hydrogen was added to attain the 2:1 stoichiometric ratio required for the FTS reaction. The product gases were analyzed using an FTIR gas cell while liquid product was analyzed using a GC/MS HP-5 column. The eggshell catalyst produced fuel preferentially in the range of middle distillates. The activity of FTS catalyst under biomass derived syngas was lower when compared to that under pure surrogates (H2/CO) due to the presence of inert components (such as methane) in the biomass derived syngas To complement the experimental study, a comprehensive model of FTS catalytic process was developed. This included both catalyst and a fixed bed reactor model. While modeling a catalyst pellet, intra-particle diffusion limitation was taken into account. For a spherical 2mm pellet, eggshell morphology provided highest activity and selectivity. The reactor model was developed by coupling intra-pellet model with inter-pellet model via reaction term. The entire process operation starting with gas injection was considered. Presence of radial temperature profile, due to wall cooling, was confirmed by Mears criterion. Thus for a fixed time duration, a 2-dimensional reactor model, with respect to temperature and concentration, was developed. The safe operational envelopes for a fixed bed reactor, using cobalt catalyst, was narrow 473 < T < 493. The extent of catalyst pore fill changed (i) the radial thermal conductivity (ii) the overall temperature and concentration profile across the bed and (iii) the limits of safe operation without reaction runaway. Finally, hydrocarbon product selectivity also varied during startup. While the catalyst pores were being filled, effluent product mainly composed of lighter, more volatile components. Once the pores are filled, heavier products started to trickle down the bed. The economics of a large scale production of liquid fuels using this technology was explored using a CHEMCAD model of a large scale process for producing liquid fuel from biomass, a sensitivity study was conducted to determine key process parameters Two different gasification technologies were compared, one that uses only biomass (BTL process) and a second process that supplements the biomass feed with natural gas for meeting energy and hydrogen needs (BGTL process). The basis for the design was 2000 metric tons of dry biomass feed per hour. The breakeven price for synthetic crude oil was estimated at $106/bbl. for the BTL plant, and $88/bbl. for a natural gas assisted BGTL plant using current market prices for raw materials utilities and capital equipment. With the increasing availability, and falling prices of natural gas, the reforming of natural gas will provide a bridge solution in the short term for economical natural gas assisted BTL conversion, thus making it competitive in marketplace.

Adequate energy supply has become one of the vital components of human development and economic growth of nations. In fact, major components of the global economy such as transportation services, communications, industrial processes, and construction activities are dependent on adequate energy resources. Even mining and extraction of energy resources, including harnessing the forces of nature to produce energy, are dependent on accessibility of sufficient energy in the appropriate form at the desired location. Therefore, energy resource planning and management to provide appropriate energy in terms of both quantity and quality has become a priority at the global level. The increasing demand for energy due to growing population, higher living standards, and economic development magnifies the importance of reliable energy plans. In addition, the uneven distribution of traditional fossil fuel energy sources on the Earth and the resulting political and economic interactions are other sources of complexity within energy planning. The competition over fossil fuels that exists due to gradual depletion of such sources and the tremendous thirst of current global economic operations for these sources, as well as the sensitivity of fossil fuel supplies and prices to global conditions, all add to the complexity of effective energy planning. In addition to diversification of fossil fuel supply sources as a means of increasing national energy security, many governments are investing in non-fossil fuels, especially renewable energy sources, to combat the risks associated with adequate energy supply. Moreover, increasing the number of energy sources also adds further complication to energy planning. Global warming, resulting from concentration of greenhouse gas emissions in the atmosphere, influences energy infrastructure investments and operations management as a result of international treaty obligations and other regulations requiring that emissions be cut to sustainable levels. Burning fossil fuel, as one of the substantial driving factors of global warming and energy insecurity, is mostly impacted by such policies, pushing forward the implementation of renewable energy polices. Thus, modern energy portfolios comprise a mix of renewable energy sources and fossil fuels, with an increasing share of renewables over time. Many governments have been setting renewable energy targets that mandate increasing energy production from such sources over time. Reliance on renewable energy sources certainly helps with reduction of greenhouse gas emissions while improving national energy security. However, the growing implementation of renewable energy has some limitations. Such energy technologies are not always as cheap as fossil fuel sources, mostly due to immaturity of these energy sources in most locations as well as high prices of the materials and equipment to harness the forces of nature and transform them to usable energy. In addition, despite the fact that renewable energy sources are traditionally considered to be environmentally friendly, compared to fossil fuels, they sometimes require more natural resources such as water and land to operate and produce energy. Hence, the massive production of energy from these sources may lead to water shortage, land use change, increasing food prices, and insecurity of water supplies. In other words, the energy production from renewables might be a solution to reduce greenhouse gas emissions, but it might become a source of other problems such as scarcity of natural resources. The fact that future energy mix will rely more on renewable sources is undeniable, mostly due to depletion of fossil fuel sources over time. However, the aforementioned limitations pose a challenge to general policies that encourage immediate substitution of fossil fuels with renewables to battle climate change. In fact, such limitations should be taken into account in developing reliable energy policies that seek adequate energy supply with minimal secondary effects. Traditional energy policies have been suggesting the expansion of least cost energy options, which were mostly fossil fuels. Such sources used to be considered riskless energy options with low volatility in the absence of competitive energy markets in which various energy technologies are competing over larger market shares. Evolution of renewable energy technologies, however, complicated energy planning due to emerging risks that emanated mostly from high price volatility. Hence, energy planning began to be seen as investment problems in which the costs of energy portfolio were minimized while attempting to manage associated price risks. So, energy policies continued to rely on risky fossil fuel options and small shares of renewables with the primary goal to reduce generation costs. With emerging symptoms of climate change and the resulting consequences, the new policies accounted for the costs of carbon emissions control in addition to other costs. Such policies also encouraged the increased use of renewable energy sources. Emissions control cost is not an appropriate measure of damages because these costs are substantially less than the economic damages resulting from emissions. In addition, the effects of such policies on natural resources such as water and land is not directly taken into account. However, sustainable energy policies should be able to capture such complexities, risks, and tradeoffs within energy planning. Therefore, there is a need for adequate supply of energy while addressing issues such as global warming, energy security, economy, and environmental impacts of energy production processes. The effort in this study is to develop an energy portfolio assessment model to address the aforementioned concerns. This research utilized energy performance data, gathered from extensive review of articles and governmental institution reports. The energy performance values, namely carbon footprint, water footprint, land footprint, and cost of energy production were carefully selected in order to have the same basis for comparison purposes. If needed, adjustment factors were applied. In addition, the Energy Information Administration (EIA) energy projection scenarios were selected as the basis for estimating the share of the energy sources over the years until 2035. Furthermore, the resource availability in different states within the U.S. was obtained from publicly available governmental institutions that provide such statistics. Specifically, the carbon emissions magnitudes (metric tons per capita) for different states were extracted from EIA databases, states' freshwater withdrawals (cubic meters per capita) were found from USGS databases, states' land availability values (square kilometers) were obtained from the U.S. Census Bureau, and economic resource availability (GDP per capita) for different states were acquired from the Bureau of Economic Analysis. In this study, first, the impacts of energy production processes on global freshwater resources are investigated based on different energy projection scenarios. Considering the need for investing on energy sources with minimum environmental impacts while securing maximum efficiency, a systems approach is adopted to quantify the resource use efficiency of energy sources under sustainability indicators. The sensitivity and robustness of the resource use efficiency scores are then investigated versus existing energy performance uncertainties and varying resource availability conditions. The resource use efficiency of the energy sources is then regionalized for different resource limitation conditions in states within the U.S. Finally, a sustainable energy planning framework is developed based on Modern Portfolio Theory (MPT) and Post-Modern Portfolio Theory (PMPT) with consideration of the resource use efficiency measures and associated efficiency risks. In the energy-water nexus investigation, the energy sources are categorized into 10 major groups with distinct water footprint magnitudes and associated uncertainties. The global water footprint of energy production processes are then estimated for different EIA energy mix scenarios over the 2012-2035 period. The outcomes indicate that the water footprint of energy production increases by almost 50% depending on the scenario. In fact, growing energy production is not the only reason for increasing the energy related water footprint. Increasing the share of water intensive energy sources in the future energy mix is another driver of increasing global water footprint of energy in the future. The results of the energies' water footprint analysis demonstrate the need for a policy to reduce the water use of energy generation. Furthermore, the outcomes highlight the importance of considering the secondary impacts of energy production processes besides their carbon footprint and costs. The results also have policy implications for future energy investments in order to increase the water use efficiency of energy sources per unit of energy production, especially those with significant water footprint such as hydropower and biofuels. In the next step, substantial efforts have been dedicated to evaluating the efficiency of different energy sources from resource use perspective. For this purpose, a system of systems approach is adopted to measure the resource use efficiency of energy sources in the presence of trade-offs between independent yet interacting systems (climate, water, land, economy). Hence, a stochastic multi-criteria decision making (MCDM) framework is developed to compute the resource use efficiency scores for four sustainability assessment criteria, namely carbon footprint, water footprint, land footprint, and cost of energy production considering existing performance uncertainties. The energy sources' performances under aforementioned sustainability criteria are represented in ranges due to uncertainties that exist because of technological and regional variations. Such uncertainties are captured by the model based on Monte-Carlo selection of random values and are translated into stochastic resource use efficiency scores. As the notion of optimality is not unique, five MCDM methods are exploited in the model to counterbalance the bias toward definition of optimality. This analysis is performed under “no resource limitation” conditions to highlight the quality of different energy sources from a resource use perspective. The resource use efficiency is defined as a dimensionless number in scale of 0-100, with greater numbers representing a higher efficiency. The outcomes of this analysis indicate that despite increasing popularity, not all renewable energy sources are more resource use efficient than non-renewable sources. This is especially true for biofuels and different types of ethanol that demonstrate lower resource use efficiency scores compared to natural gas and nuclear energy. It is found that geothermal energy and biomass energy from miscanthus are the most and least resource use efficient energy alternatives based on the performance data available in the literature. The analysis also shows that none of the energy sources are strictly dominant or strictly dominated by other energy sources. Following the resource use efficiency analysis, sensitivity and robustness analyses are performed to determine the impacts of resource limitations and existing performance uncertainties on resource use efficiency, respectively. Sensitivity analysis indicates that geothermal energy and ethanol from sugarcane have the lowest and highest resource use efficiency sensitivity, respectively. Also, it is found that from a resource use perspective, concentrated solar power (CSP) and hydropower are respectively the most and least robust energy options with respect to the existing performance uncertainties in the literature. In addition to resource use efficiency analysis, sensitivity analysis and robustness analysis, of energy sources, this study also investigates the scheme of the energy production mix within a specific region with certain characteristics, resource limitations, and availabilities. In fact, different energy sources, especially renewables, vary in demand for natural resources (such as water and land), environmental impacts, geographic requirements, and type of infrastructure required for energy production. In fact, the efficiency of energy sources from a resource use perspective is dependent upon regional specifications, so the energy portfolio varies for different regions due to varying resource availability conditions. Hence, the resource use efficiency scores of different energy technologies are calculated based on the aforementioned sustainability criteria and regional resource availability and limitation conditions (emissions, water resources, land, and GDP) within different U.S. states, regardless of the feasibility of energy alternatives in each state. Sustainability measures are given varying weights based on the emissions cap, available economic resources, land, and water resources in each state, upon which the resource use efficiency of energy sources is calculated by utilizing the system of systems framework developed in the previous step. Efficiency scores are graphically illustrated on GIS-based maps for different states and different energy sources. The results indicate that for some states, fossil fuels such as coal and natural gas are as efficient as renewables like wind and solar energy technologies from resource use perspective. In other words, energy sources' resource use efficiency is significantly sensitive to available resources and limitations in a certain location. Moreover, energy portfolio development models have been created in order to determine the share of different energy sources of total energy production, in order to meet energy demand, maintain energy security, and address climate change with the least possible adverse impacts on the environment. In fact, the traditional “least cost” energy portfolios are outdated and should be replaced with “most efficient” ones that are not only cost-effective, but also environmentally friendly. Hence, the calculated resource use efficiency scores and associated statistical analysis outcomes for a range of renewable and nonrenewable energy sources are fed into a portfolio selection framework to choose the appropriate energy mixes associated with the risk attitudes of decision makers. For this purpose, Modern Portfolio Theory (MPT) and Post-Modern Portfolio Theory (PMPT) are both employed to illustrate how different interpretations of “risk of return” yield different energy portfolios. The results indicate that 2012 energy mix and projected world's 2035 energy portfolio are not sustainable in terms of resource use efficiency and could be substituted with more reliable, more effective portfolios that address energy security and global warming with minimal environmental and economic impacts.
Ph.D.
Doctorate
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering

Commercial Buildings and complexes are no longer just national heat and power network energy loads, but they are becoming part of a smarter grid by including their own dedicated local heat and power generation. They do this by utilising both heat and power networks/micro-grids. A building integrated approach of Combined Heat and Power (CHP) generation with photovoltaic power generation (PV) abbreviated as CHPV is emerging as a complementary energy supply solution to conventional (i.e. national grid based) gas and electricity grid supplies in the design of sustainable commercial buildings and communities. The merits for the building user/owner of this approach are: to reduce life time energy running costs; reduce carbon emissions to contribute to UK’s 2020/2030 climate change targets; and provide a more flexible and controllable local energy system to act as a dynamic supply and/or load to the central grid infrastructure. The energy efficiency and carbon dioxide (CO2) reductions achievable by CHP systems are well documented. The merits claimed by these solutions are predicated on the ability of these systems being able to satisfy: perfect matching of heat and power supply and demand; ability at all times to maintain high quality power supply; and to be able to operate with these constraints in a highly dynamic and unpredictable heat and power demand situation. Any circumstance resulting in failure to guarantee power quality or matching of supply and demand will result in a degradation of the achievable energy efficiency and CO2 reduction. CHP based local energy systems cannot rely on large scale diversity of demand to create a relatively easy approach to supply and demand matching (i.e. as in the case of large centralised power grid infrastructures). The diversity of demand in a local energy system is both much greater than the centralised system and is also specific to the local system. It is therefore essential that these systems have robust and high performance control systems to ensure supply and demand matching and high power quality can be achieved at all times. Ideally this same control system should be able to make best use of local energy system energy storage to enable it to be used as a flexible, highly responsive energy supply and/or demand for the centralised infrastructure. In this thesis, a comprehensive literature survey has identified that there is no scientific and rigorous method to assess the controllability or the design of control systems for these local energy systems. Thus, the main challenge of the work described in this thesis is that of a controller design method and modelling approach for CHP based local energy systems. Specifically, the main research challenge for the controller design and modelling methodology was to provide an accurate and stable system performance to deliver a reliable tracking of power drawn/supplied to the centralised infrastructure whilst tracking the require thermal comfort in the local energy systems buildings. In the thesis, the CHPV system has been used as a case study. A CHPV based solution provides all the benefits of CHP combined with the near zero carbon building/local network integrated PV power generation. CHPV needs to be designed to provide energy for the local buildings’ heating, dynamic ventilating system and air-conditioning (HVAC) facilities as well as all electrical power demands. The thesis also presents in addition to the controller design and modelling methodology a novel CHPV system design topology for robust, reliable and high-performance control of building temperatures and energy supply from the local energy system. The advanced control system solution aims to achieve desired building temperatures using thermostatic control whilst simultaneously tracking a specified national grid power demand profile. The theory is innovative as it provides a stability criterion as well as guarantees to track a specified dynamic grid connection demand profile. This research also presents: design a dynamic MATLAB simulation model for a 5-building zone commercial building to show the efficacy of the novel control strategy in terms of: delivering accurate thermal comfort and power supply; reducing the amount of CO2 emissions by the entire energy system; reducing running costs verses national rid/conventional approaches. The model was developed by inspecting the functional needs of 3 local energy system case studies which are also described in the thesis. The CHPV system is combined with supplementary gas boiler for additional heating to guarantee simultaneous tracking of all the zones thermal comfort requirements whilst simultaneously tracking a specified national grid power demand using a Photovoltaics array to supply the system with renewable energy to reduce amount of CO2 emission. The local energy system in this research can operate in any of three modes (Exporting, Importing, Island). The emphasise of the thesis modelling method has been verified to be applicable to a wide range of case studies described in the thesis chapter 3. This modelling framework is the platform for creating a generic controlled design methodology that can be applied to all these case studies and beyond, including Local Energy System (LES) in hotter climates that require a cooling network using absorption chillers. In the thesis in chapter 4 this controller design methodology using the modelling framework is applied to just one case study of Copperas Hill. Local energy systems face two types of challenges: technical and nontechnical (such as energy economics and legislation). This thesis concentrates solely on the main technical challenges of a local energy system that has been identified as a gap in knowledge in the literature survey. The gap identified is the need for a controller design methodology to allow high performance and safe integration of the local energy system with the national grid infrastructure and locally installed renewables. This integration requires the system to be able to operate at high performance and safely in all different modes of operation and manage effectively the multi-vector energy supply system (e.g. simultaneous supply of heat and power from a single system).

The 2040 governmental goal of 100 % renewable electricity in Sweden means that there will be a shift in electricity production and a phasing out of nuclear power. This nuclear power has to be replaced by some other source. Wind power is a viable alternative, thanks to its reliability and the abundance of wind in Sweden. However, wind power production requires a large amount of land and carries the risk of disrupting the landscape. Wind energy is therefore often difficult to develop, and when developed it is often in rural areas where it disturbs as few people as possible. This study presents an alternative to rural exploitation, it investigates whether it is possible to produce sufficient wind power to satisfy urban demand within 20 000 meters of the 20 largest cities in Sweden. Firstly, the criteria for areas where wind power can be developed were synthesised. Secondly a numerical model was used to simulate energy demand in TWh considering the future growth in demand and the phasing out of nuclear power. The demand for wind power was then translated into correlating area in km2. Finally, a GIS analysis was conducted to estimate the extent of area suitable for wind power development based on the criteria above and within a 20 000m perimeter from the 20 largest cities in Sweden. The analysis showed that only 35 % of the required area for wind power development fulfilled the criteria within the given perimeter. From the GIS analysis only 940.73 km2 was found to be suitable. From the numerical model, the results showed that for it to be sufficient, there would have to be at least 2687.1 km2 suitable land. The conclusion from this study is that in order to phase out the nuclear power, the majority of the wind power has to be located in the rural areas.

The purpose of this study is to exlpore the possibilities of power generation using human and mechanical means. This paper will introduce alternative means, methods, and procedures for the implementation of cutting edge technologies to address the energy needs for today and the future. Further, this project will serve as an aid in the development of a base camp facility layout optimization system by understanding the proximity relationships between base camp components, developing a facility layout domain, and comparing generated layouts to existing models and camps.

Municipal energy systems in Nordic environments face multiple challenges: the cold climate, large-scale industries, a high share of electric heating and long distances drive energy consumption. While actions on the demand side minimize energy use, decarbonization efforts in mining, industries, the heating and the transport sector can increase the consumption of electricity and biofuels. Continued growth of intermittent wind and solar power increases supply, but the planned phase out of Swedish nuclear power will pose challenges to the reliability of the electricity system in the Nordic countries. Bottlenecks in the transmission and distribution grids may restrict a potential growth of electricity use in urban areas, limit new intermittent supply, peak electricity import and export. Environmental concerns may limit growth of biomass use. Local authorities are committed in contributing to national goals on mitigating climate change, while considering their own objectives for economic development, increased energy self-sufficiency and affordable energy costs. Given these circumstances, this thesis investigates existing technical and economic potentials of renewable energy (RE) resources in the Nordic countries with a focus on the northern counties of Finland, Norway and Sweden. The research further aims to provide sets of optimal solutions for sustainable Nordic municipal energy systems, where the interaction between major energy sectors are studied, considering multiple objectives of minimizing annual energy system costs and reducing carbon emissions as well as analyzing impacts on peak electricity import and export. This research formulates an integrated municipal energy system as a multi-objective optimization problem (MOOP), which is solved by interfacing the energy system simulation tool EnergyPLAN with a multi-objective evolutionary algorithm (MOEA) implemented in Matlab. In a first step, the integration or coupling of electricity and heating sectors is studied, and in a second step, the study inquires the impacts of an increasingly decarbonized transport sector on the energy system. Sensitivity analysis on key economic parameters and on different grid emission factors is performed. Piteå (Norrbotten County, Sweden) is a typical Nordic municipality, which serves as a case study for this research. The research concludes that significant techno-economic potentials exist for the investigated resources. Optimization results show that CO2 emissions of a Nordic municipal energy system can be reduced by about 60% without a considerable increase in total energy system costs and that peak electricity import can be reduced by up to 38%. The outlook onto 2030 shows that the transport sector could be composed of high electrification shares and biofuels. Technology choices for optimal solutions are highly sensitive to electricity prices, discount rates and grid emission factors. The inquiries of this research provide important insights about carbon mitigation strategies for integrated energy sectors within a perspective on Nordic municipalities. Future work will refine the transport model, develop and apply a framework for multi-criteria decision analysis (MCDA) enabling local decision makers to determine a technically and economically sound pathway based on the optimal alternatives provided, and analyze the existing policy framework affecting energy planning of local authorities.
Kommunala energisystem i nordiska miljöer möter flera utmaningar: det kalla klimatet, storskaliga industrier, en stor andel elvärme och långa distanser driver energiförbrukningen. Medan åtgärder vidtas på efterfrågesidan för att minimera energianvändningen, kan utsläppsminskande åtgärder inom gruvdrift, industrier, uppvärmningen och transportsektorn öka förbrukningen av el och biobränslen. Fortsatt tillväxt av intermittent vind- och solkraft ökar elproduktion, men den planerade avvecklingen av svensk kärnkraft kommer att utmana tillförlitligheten i elsystemet i de nordiska länderna. Flaskhalsar i överförings- och distributionsnäten kan begränsa en potentiell tillväxt av elanvändningen i stadsområden, begränsa ny intermittent utbud, och påverka elutbyte mellan länderna. Miljöhänsyn kan begränsa ökad användning av biomassa. Lokala myndigheter är engagerade i att bidra till nationella klimatmål, samtidigt som de följer sina egna mål för ekonomisk utveckling, ökad självförsörjning av energi och överkomliga energikostnader. Mot bakgrund av dessa omständigheter undersöker denna avhandling befintliga tekniska och ekonomiska potentialer för förnybar energi i Norden med fokus på de nordliga länen i Finland, Norge och Sverige. Forskningen syftar vidare till att utveckla optimala lösningar för hållbara nordiska kommunala energisystem, där samspelet mellan stora energisektorer studeras, med tanke på att minimera årliga energisystemkostnader och samtidigt minska koldioxidutsläppen samt analysera påverkan på elimport till och export från kommunen. Denna forskning formulerar ett integrerad kommunalt energisystem som multimåloptimeringsproblem (multi-objective optimisation problem - MOOP), som löses genom att kombinera simuleringsverktyget EnergyPLAN med en evolutionär algoritm implementerad i Matlab. I ett första steg studeras kopplingen av el- och värmesektorerna, och i ett andra steg effekterna av en integrerad och alltmer förnybar transportsektor på energisystemet. Känslighetsanalys på viktiga ekonomiska parametrar och på olika utsläppsfaktorer utförs. Piteå (Norrbottens län, Sverige) är en typisk nordisk kommun som fungerar som en fallstudie för detta arbete. Forskningens slutsatser innebär att det finns betydande teknisk-ekonomiska potentialer för de undersökta förnybara resurserna. Optimeringsresultaten visar att koldioxidutsläppen från ett nordiskt kommunalt energisystem kan minskas med cirka 60% utan en avsevärd ökning av de totala energisystemkostnaderna och att den högsta elimporten kan minskas med upp till 38%. Resultat för år 2030 visar att transportsektorn kan ha en mycket hög elektrifieringsgrad och samtidigt används biobränslen i tunga fordon. Optimala lösningar är mycket känsliga för elpriser, räntor och utsläppsfaktorer. Detta arbete ger viktiga insikter om strategier för koldioxidminskning för integrerade energisektorer i ett perspektiv på nordiska kommuner. Min framtida forskning kommer att förfina transportmodellen, utveckla och tillämpa ett ramverk för beslutsanalys med flera kriterier (multi-criteria decision analysis - MCDA) som ska stödja lokala myndigheter att fastställa tekniskt och ekonomiskt hållbara lösningar i deras energiplanering.

Ukraine belongs to energy-scarce countries and satisfies its needs in energy resources by domestic mining less than 50% (including with consumption of the imported natural gas per capita Ukraine ranks/holds the first place in the world). In addition, the fuel and energy resources efficiency use in the economy is low, energy intensity of gross domestic product is twice higher than the energy intensity in the industrialized world countries. In addition, a significant gap between Ukraine and countries of the EU in the energy efficiency is certified by a comparative assessment of a number of aspects of the energy sector and other sectors of economy, mainly of energy intensive ones. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/36864

Yes
Concrete with smart and functional properties (e.g., self-sensing, self-healing, and energy-harvesting) represents a transformative direction in the field of construction materials. Energy-harvesting concrete has the capability to store or convert the ambient energy (e.g., light, thermal, and mechanical energy) for feasible uses, alleviating global energy and pollution problems as well as reducing carbon footprint. The employment of energy-harvesting concrete can endow infrastructures (e.g., buildings, railways, and highways) with energy self-sufficiency, effectively promoting sustainable infrastructure development. This paper provides a systematic overview on the principles, fabrication, properties, and applications of energy-harvesting concrete (including light-emitting, thermal-storing, thermoelectric, pyroelectric, and piezoelectric concretes). The paper concludes with an outline of some future challenges and opportunities in the application of energy-harvesting concrete in sustainable infrastructures.
The full-text of this article will be released for public view at the end of the publisher embargo on 19 Jul 2022.

Swine production represents approximately 40% of the world's meat production, and swine wastes contain high concentrations of organic matter, nitrogen (N) and phosphorus (P). Swine production is intensifying as meat demand increases and concentrated animal feeding operations (CAFOs) are becoming increasingly common, making it difficult to treat the waste generated. A system for holistic treatment of swine waste produced in CAFOs was investigated in this study that sustainably generates energy and recovers N and P as saleable fertilizers. The system uses anaerobic digestion (AD) for methane production and solids stabilization, followed by precipitation of struvite (MgNH4PO4*6H2O) and recovery of N by ion exchange onto natural zeolites. This process is expected to mitigate both eutrophication of receiving waters and greenhouse-gas emissions while generating products that meet agronomic nutrient demands; however, the economic and environmental sustainability remains unknown. The objectives of this study were to: (1) evaluate water quality and the fate of nutrients and ions in each step in the proposed system through pilot and bench scale experiments, (2) evaluate content/quality of struvite precipitates formed in wastewater treatment processes, (3) assess basic composition of zeolite materials that are being considered for use as IX materials, (4) quantify the environmental impact of the proposed system, and (5) estimate the economic benefits and costs of the proposed system. The results of a bench scale evaluation of the system show that although water quality greatly improves throughout the treatment process, the effluent water quality has high concentrations of COD (2,803 mg O2/L) and E. coli (106.3 CFU/100ml). This limits reuse options for the reclaimed water, however a variety of on-farm applications may be suitable. During struvite precipitation, the recovery efficiency of SRP was 87% (60 mg/L recovered); however, although measurements that take into account P in suspended solids show a lower recovery efficiency, they also show higher mass recovery (77% efficiency, 66 mg/L recovered). N recovery during struvite precipitation showed a similar trend, with 49% of TN and 7% of NH4-N being recovered. Struvite recovery can only occur from NH4-N and soluble reactive P. The additional recovery observed is likely due to adsorption of the nutrients onto the precipitate. Therefore, to accurately measure and report recovery, measurements of N and P that take into account suspended solids should be used. In most wastes, magnesium is the limiting constituent for struvite formation, but for swine AD effluents, P is the limiting constituent. Therefore, a higher soluble P concentration would increase recovery potential. The majority of the remaining N and P as well as a significant amount of potassium (K) were recovered during IX. Six struvites from commercial processes as well as our bench-scale experiments were assessed and compared by X-ray diffraction, SEM imaging, and SEM-EDX scans. All samples were confirmed as struvite by XRD, however they varied widely in crystal size and shape. The elemental composition of the samples was similar; however, struvite formed from phosphate mining waste had higher amounts Mg and P, indicating more pure struvite formation. The presence of impurities in some samples was likely due to the reactor design and solids separation methods. XRD was also used to confirm the identity of zeolites. Three clinoptilolites had similar crystal size and elemental composition except for Zeosand [reg] which showed a surface roughness, which likely contributes to higher cation exchange capacity. Chabazite has smaller crystal size and larger pores than clinoptilolite, which also likely contributes to its higher capacity. Life cycle assessment (LCA) was used to evaluate the environmental sustainability of the system and the results suggested that environmental benefits were provided across almost all impact categories. Two alternatives for raising the pH in struvite precipitation (NaOH addition vs. aeration) and two alternatives for zeolite IX materials (chabazite vs. clinoptilolite) were assessed, but there were negligible differences between alternatives. The system was also assessed at a medium and large scale, and the large scale was more environmentally friendly across all categories. Operational impacts were significantly greater than construction impacts; therefore, the environmental impact of the system can be accurately assessed by only including operation. A life cycle cost assessment (LCCA) was also performed on the system and showed a payback period of 39 years for a medium sized system and 15 years for a large size. This, however, is when compared to a "business-as-usual" scenario and does not consider renewable energy credits or government grants. Furthermore, although a larger system is more economically beneficial, this must be balanced with quality of animal care. From a cost standpoint, IX recovery using chabazite is not recommended and struvite precipitation using aeration is more economically beneficial than NaOH addition.

Growth in aviation has resulted in large airports that can be described as Airport Metropolises. This thesis reviews a variety of sustainable energy options that are suitable for such airports, and presents a decision support framework that can be used to guide decision makers towards the adoption of sound sustainable energy projects and practices. The thesis demonstrates use of the decision support framework via a number of case studies and outlines a methodology which could be incorporated within a Decision Support System.

With the raising concerns about the environment, the ICT equipments have been pointed out as a major and ever rising source of energy consumption and pollution. Among those ICT equipments, data centres play obviously a major role with the rise of the Cloud computing paradigm. In the recent years, researchers have focused on reducing the energy consumption of data centres. Furthermore, future environmentally friendly data centres are also expected to prioritize the usage of renewable energies over brown energies. However, managing the energy consumption within a data centre is challenging because data centres are complex facilities which supports a huge variety of hardware, computing styles and SLAs. Those may evolve through time as user requirements can change rapidly. Furthermore, differently from non-renewable energy sources, the availability of renewable energies is very volatile and time dependent: e.g. solar power is obtainable only during the day, and is subject to variations due to the meteorological conditions. The goal in this case is to shift the workload of running applications, according to the forecasted availability of the renewable energy. In this thesis we propose a flexible framework called Plug4Green able to reduce the energy consumption of a Cloud data centre. Plug4Green is based on the Constraint Programming paradigm, allowing it to take into account a great number of constraints regarding energy, hardware and SLAs in data centres. We also propose the concept of an energy adaptive software controller (EASC), able to augment the usage of renewable energies in data centres. The EASC supports two kind of applications: service-oriented and task-oriented applications; and two kind of computing environments: Infrastructure as a Service and Platform as a Service. We evaluated our solutions in several trials executed in the testbeds of Milan and Trento, Italy. Results show that Plug4Green was able to reduce the power consumption by 27% in the Milan trial, while the EASC was able to augment the renewable energy percentage by 7.07pp in the Trento trial.