Existing low-voltage networks may not accommodate high penetrations of low-carbon technologies. The topic of this thesis is unbalance, which if minimised can delay or avoid the constraining of these technologies or the replacing of still-useful network assets. Most of the discussion on unbalance, as seen in the standards and the literature, centres on the effects of voltage unbalance on consumer equipment. Its effects on the network are not equally reported. This thesis recognises fundamental differences between the consumer and network perspectives. It can inform distribution network operators on the interpretation of measurements taken on low-voltage networks and guide research on unbalance due to high penetrations of low-carbon technologies. Much of the work involved simulations of LV networks. Initially, existing 3 x 3 or 5 x 5 approaches to the forward-backward sweep method were thought suitable. After a review of these approaches however, there were doubts as to how accurately they accounted for the shared neutral-earth return path on which the out-of-balance current flows. This led to the derivation of a new 5 x 5 approach using only Kirchhoff s voltage (KVL) and current laws (KCL). Its results are validated thoroughly in the thesis. In addition to satisfying KVL and KCL, they match Matlab SimPowerSystems exactly and are in close agreement with measurements taken on a very unbalanced rural feeder. This thesis also investigates the mitigation of unbalance using the static balancer. This is a transformer with a single interconnected-star winding. It was used in 1930-1950s to correct unbalance. Contributions are made for its possible re-introduction as a retrofit option. They include a model for use in the forward-backward sweep method, validated by laboratory and field measurements, and the quantification of the static balancer s strengths and weaknesses as this can help identify when it should be used.

The risks and opportunities that climate change presents for Small and Medium-Sized Enterprises (SMEs) have been largely overlooked by previous research (Schaefer et al. 2011, Williams & Schaefer 2013). The subsequent lack of knowledge in this field makes a meaningful, profitable and sustainable engagement of SMEs with climate change challenging. Current research has difficulty explaining (1) why SMEs rarely engage with climate change (2) how climate change is currently communicated to SMEs and (3) how SMEs overcome the knowledge gap between business practice and climate change science (cf. Hoffman 2004, 2006, Hart 2007, Goodall 2008). In this thesis I critically examine 31 SMEs which engage with climate change knowledges, 5 Innovation-Support-Organizations (ISOs) which communicate climate change knowledges and 2 business-led communities of practice that discuss climate change-related business practices. Over a three-year period, I explore why and how business leaders approach the knowledge gap between climate change science and business practice, drawing on a variety of ethnographic research methods: (1) in-depth semi-structured and open interviews; (2) participant observations; (3) practitioner's workshops; and (4) an online survey. My research demonstrates that the participating ISOs communicate climate change in an overly simplistic way. The participating ISOs focus on persuading business leaders to engage with climate change. The participating business leaders who hear this persuasive message are already willing to engage with climate change. Their motivations to engage are lay-knowledge-dependent, derived from personal values, space and place identity. What the participating business leaders require is practical advice on how to mitigate the impact of, and adapt to, climate change, and they therefore try to overcome the limitations of current climate change communication through forming and joining communities of practice. By doing this, they can make sense of climate change in specialist niche communities and benefit from social belief systems. To enhance the number of SMEs engaging with climate change, I recommend that the participating ISOs target the personal values of business leaders and actively use these specialist niche communities niches within which the participating business leaders develop business practice to learn about climate change-related business practices themselves. Overall, my PhD shows that to create meaningful, profitable and sustainable engagement with climate change, business leaders and ISOs, as well as governments and society, need to address their "confusion and anxiety about the goals, ambitions and destinies [they] foresee" for themselves (Hulme 2013: 298).

<p>Predstavljena je nova metoda intenzivne plastične deformacije &ndash; višefazno sabijanje V-alatom. Koristeći ovu metodu, sabijanjem u osamnaest faza, unapređene su mehaničke osobine niskougljeničnog čelika Č.1221 &ndash; tvrdoća, čvrstoća i deformabilnost. Za ispitivanje mikrostrukture korišćeni su svetlosni, skening i transmisioni mikroskop. Prosečna veličina kristalnog zrna početnog materijala od 19 mikrometara je smanjena na 250 nanometara nakon dvanaest faza sabijanja. Nakon osamnaest faza sabijanja na čelu uzorka ostvarena je ukupna deformacija u iznosu od 3,38.</p> / <p>A new severe plastic deformation method has been presented - multistage upsetting by V-shape dies. By using this method, in eighteen upsetting stages, mechanical propreties (hardness, strenght and formability) of C15E low carbon steel has been improved. For microstructure analysis light, scanning and transmission microscopes have been employed. Initial average grain size of 19 &mu;m has been reduced to 250 nm after twelve upsetting stages. After eighteen upsetting stages, total effective deformation at the sample forehead of 3,38 has been obtained.</p>

The implementation of a low carbon electricity system within the GB requires a significant change to the generation mix with an increasing role for renewable generation. Much of this generation will be intermittent. To date system balancing has largely relied on predicting demand and ensuring provision. With substantial intermittency, continuation of this paradigm necessitates significant investment in peaking plant and/or storage. However, some of this investment can be avoided by harnessing the flexibility inherent in many electrical loads. Despite the attractiveness of such services, we do not see their large-scale implementation. The aim of this thesis is to consider why. A historical analysis reveals that both nationalisation and subsequent privatisation provide precedents for significant structural change as the integration of large-scale flexible demand might require. The need for political will is identified as a crucial enabling factor. Without an ideological driver, however, a perception of economic and/or technological risk can preclude the implementation of supportive policy. This perception is addressed through demonstration. An effective demonstration must show the ability to aggregate many small loads in a coordinated manner. A genetic algorithm that provides this core dispatch and optimisation capability is presented. This algorithm is shown to be effective in aggregating many small loads to provide a net effect that can be used as a balancing service and to do so in an optimal way considering both cost and reliability. Having demonstrated feasibility appropriate incentives must be created. An initial outline for a framework based on SysML is presented that can be used to identify where structural barriers to implementation are present to aid the design of appropriate policy incentives.

Na última década em diversos países do mundo vem crescendo o debate para o aumento do uso da madeira, em especial para o setor da construção civil, incentivado por dois motivos principais: pela capacidade de absorção de CO2 e consequente contribuição para a economia de baixo carbono e o desenvolvimento de novas tecnologias industrializadas, predominantemente aquelas conhecidas como mass timber. Apesar de 60% do território brasileiro ser coberto por florestas e do potencial madeireiro do país, o uso da madeira como material construtivo é pouco expressivo. No entanto, em consonância com o debate mundial, o Brasil também dá indícios de desenvolvimento do setor da construção civil em madeira. Este trabalho teve como objetivo caracterizar a tendência de aumento do uso da madeira através do levantamento dos agentes envolvidos nesse processo; das ações para a promoção do uso do material e dos produtos disponíveis no mercado. Também foram identificados os obstáculos enfrentados, as motivações e as perspectivas futuras. Cabe ressaltar que a pesquisa foi realizada com foco no setor privado e com o uso da madeira predominantemente em edificações na forma de estrutura e/ou vedação. Foram utilizadas duas abordagens metodológicas: mapeamento sistêmico e estudo de caso. O mapeamento sistêmico foi composto pelo levantamento bibliográfico e pesquisa documental, que num primeiro momento identificou quem são os principais agentes envolvidos e posteriormente, levantou dados sobre sua atuação e produção. Como resultado, foram identificadas 42 instituições e 66 empresas, além de 24 produtos entre sistemas, subsistemas e componentes construtivos e 20 ações de promoção da madeira, entre eventos, programas e mídia. Posteriormente foram selecionados 22 agentes, com base na expressividade em sua área de atuação, entre empresas e instituições, para a aplicação de entrevistas semi-estruturadas visando levantar as motivações e entraves do setor. Com isso foi possível verificar o aumento do número de empresas atuantes com tecnologias construtivas em madeira, e da variedade de produtos disponíveis no mercado, com destaque para as tecnologias industrializadas, assim como de ações para a promoção da madeira, particularmente no ano de 2017. Constatou-se ainda que o fenômeno trata-se não do aumento do uso da madeira em si, mas das tecnologias em produtos industrializados e que existe uma aproximação entre o setor florestal e da construção civil, o que é fundamental para o pleno desenvolvimento da cadeia produtiva. E por fim, apesar de haverem diversos entraves a serem sobrepostos, a expectativa é de que os produtos industrializados em madeira tenham uma participação cada vez maior na construção civil brasileira nos próximos anos. / Over the last decade the debate about the rise of use of wood, specially in the construction sector, is growing because of two main reasons: the potential to stock CO2 and consequently to contribute to a low carbon economy and the development of industrialized technologies, predominantly those known as mass timber. Even though roughly 60% of the Brazilian territory is covered by forests and the potential of the forestry sector the use of wood as a construction material is incipient. Nevertheless in consonance with a global trend, there are evidences indicating the development of the timber construction industry in Brazil. This research aimed to characterise this trend through the identification of the main stakeholders, the initiatives to promote wood and the available products on the market. Also, matters related to obstacles, motivations and future perspectives were also analysed. It is important to highlight that the research focused on the private sector with the use of wood predominantly on buildings as structure and/or sealing. To accomplish it two methods were used: systemic mapping and study case. The systemic mapping consisted on both the research through the scientific literature and documents (i. e. catalogs, data available on websites) which identified 42 institutions, 66 companies, 24 different products among construction systems and components, and also 20 wood promotion actions (i. e. conferences, programs, media). Afterwards 22 stakeholders among companies and institutions were selected based on the relevance of their activities. Then semi-structured interviews were conducted to collect data about the difficulties, motivations and perspectives of the timber construction sector. As a result it was identified a rise on the quantity of companies, variety of products available on the market (specially engineered wood products) and wood promotions initiatives, particularly on the year of 2017. The study revealed that the development is not about the use of wood itself, but instead highly industrialized products. There is also the approximation between the forest and civil construction sector, which is essential for the full development of the production chain. Besides, despite the many obstacles found, it is expected for the next years a consistent growth of engineered wood products in Brazilian civil construction sector.

The following project aims to create a decentralised heat network development methodology which makes best use of heat sources and loads and can be widely applied to evaluate the energy economics of a heat network scheme and energy centre. As the energy transition takes shape, the key is connectivity and the potential now, or in the future to aid progressive development of energy systems and technologies rather than traditional models that consider schemes individually in isolation and not holistically; where with the latter we’re more likely to end up with robust, future-proof solutions.   A methodology was formulated which encompassed various elements of decentralised energy masterplanning approaches and enabled heat demand loads and associated profiles to be simulated. The development of an optimisation model enabled strategies to be devised (maximisation of energy generation and revenue independently) over a set technology lifetime for the energy centre.   The results have concluded that the maximisation of revenue optimisation strategy is the most viable economically. An energy generation optimisation for the energy centre produced optimal results in terms of its heat generation profile, however, the scheme was not economically viable due to significantly high capital costs associated with piping connections to multiple clusters.   A CO2 emission analysis was carried out for a selection of energy technologies (CHP, heat pumps and gas boilers) for the heat network energy centre. An evaluation of the results has concluded that the optimal selection of technology for the energy centre for the minimisation of CO2 emissions is heat pumps. When selecting combinations of technologies for peak and base loads within the energy centre, heat pumps (base load) and gas boilers (peak load) are optimal when aiming to maximise revenue generation whilst minimising CO2 emissions. In this case, reductions in associated CO2 emissions have been calculated to achieve up to 89.07% when compared to a base case gas boiler technology (energy centre) scenario alone.   The methodology and models developed in this project can be widely applied to decentralised heat network projects in London in order to identify optimal development and expansion strategies and evaluate the energy economics of schemes.

O processo de conformação de chapas planas, estampagem, consiste na obtenção de peças conforme o projeto do processo e do produto. Faz-se necessária uma margem de segurança para que as variações de processo e do material possam ser absorvidas e o sucesso seja alcançado no processo de produção do componente. O presente trabalho mostra aspectos de estampabilidade de uma chapa de aço de baixo teor de carbono, o material mais utilizado no processo de estampagem. Estes aspectos são descritos e demonstrados como influenciam no processo de estampagem. No caso prático apresentado, evidencia-se que com a aplicação dos conhecimentos científicos de comportamento mecânico do material obtém-se uma melhoria no desempenho do processo e, conseqüentemente, na redução de custos e no aumento de competitividade. Como objetivo principal, tem o presente trabalho estudar a influência da redução a frio de acabamento do processo de relaminação no coeficiente de encruamento e mostrar como este estudo teve participação na solução e aplicação de uma peça-exemplo. Conseqüentemente há como objetivos secundários o estudo da influencia do tamanho de grão no coeficiente de encruamento, o desenvolvimento da textura cristalográfica antes e após a conformação da peça-exemplo e demonstrar a importância da utilização do método de elementos finitos no processo de conformação por estampagem para determinação dos tipos de conformação predominante no processo. Para realização do trabalho foram utilizados dois aços de baixo teor de carbono com composição química semelhantes porem com processos de fabricação diferenciados. Atenção especial foi dada a redução aplicada na laminação de acabamento de ambos os aços, através do uso de medidores de espessura e redução através de raios-X. Os aços foram caracterizados antes da conformação da peça-exemplo quanto a orientação cristalográfica através de difração de raios-X e EBSD, quanto as propriedades mecânicas através de ensaios mecânicos de tração e quanto a microestrutura e tamanho de grão através de metalografia. Foi realizada uma simulação de estampagem da peça-exemplo através de elementos finitos afim de determinar o tipo de conformação predominante na região mais solicitada da peça-exemplo. A peça exemplo foi conformada na pratica e caracterizada a distribuição das deformações através da medições da rede circulo previamente impressa na superfície da chapa na região mais solicitada conforme previamente determinado através da simulação. A orientação cristalográfica da região mais solicitada também foi caracterizada. Os resultados mostram a influencia de uma pequena variação na redução, 0,73% e 0,34%, aplicada na laminação de acabamento no coeficiente de encruamento. Para confirmação de que a redução aplicada foi a principal influenciadora no resultado o coeficiente de encruamento foi calculado através de equações disponíveis na literatura que correlacionam composição e tamanho de grão com o coeficiente de encruamento. A textura preferencial dos dois aços também foi avaliada através de figuras de função de orientação da distribuição e o comportamento dos dois aços foi relativamente semelhante, onde o aço com melhor desempenho demonstrou um aumento na componente {223} também conhecida como &#947;'. O estudo através de elementos finitos mostra que região mais solicitada da peça tem conformação predominada por estiramento. Por fim é mostrada a melhor distribuição das deformações na peça-exemplo produzida com aço de maior coeficiente de encruamento. Concluindo o trabalho permitiu a avaliação da influencia da redução aplicada na laminação de acabamento de aços de baixo teor de carbono nas propriedades mecânicas do aço e também o resultado deste comportamento mecânico na peça-exemplo adotada.Também permitiu avaliar a evolução da textura cristalográfica dos dois aços escolhidos antes e após a conformação da peça-exemplo. / The forming process of plain sheets, stamping, consists on the obtainment of parts according to the project of the process and the product. A safety margin becomes necessary so that the process variations and of the material can be absorbed and the success is reached in the process of production of the component. The present paper shows aspects of formability of a steel sheet of low carbon content, the most used material in the stamping process. These aspects are described and demonstrated how they influence the stamping process. In the presented case, it is proven that with the application of the scientific knowledge of mechanical behavior of the material an improvement in the performance of the process is reached and, consequently, the reduction of costs and the increase of competitiveness. As main objective, the present work study the influence of the cold reduction applied on skin pass of the cold rolling process on the strain hardening coefficient and to show how this study had participated on the solution and application of an part. Consequently it has as secondary objective the study of influences of the size of grain in the coefficient of strain hardening, the development of texture before and after forming of the part and to demonstrate the importance of the use of the method of finite elements in the forming process for determination of the predominant types of forming in the stamping process. For accomplishment of this paper two steel of low carbon content had been used with similar chemical composition but with differentiated rolling processes of manufacture. Special attention was given to the reduction applied in the skin pass of both steel, through the use of measurers of thickness and reduction through x-ray. The steel had been characterized before the stamping of the part above crystallographic texture through x-ray diffraction and EBSD, above mechanical properties through mechanical tensile tests and above microstructure and size of grain through metallography. A simulation of stamping process of the part through finite elements was carried out with the objective of determine the type of predominant forming in the most requested region of the part. The part was formed in mechanical presses and characterized the distribution of the deformations through the measurements circle grids, previously printed in the surface of the sheet, in the region most requested as previously determined through the simulation. The crystallographic orientation of the most requested region was also characterized. The results show influence of a small variation in the rolling reduction, 0.73% and 0.34%, applied in the skin pass on the strain hardening coefficient. For confirmation that the pplied skin pass was the main influence in the strain hardening coefficient result, was calculated hrough available equations in literature that correlate composition and grain size with the strain hardening coefficient. The preferential texture of two steel was also evaluated through figures of orientation function distribution and the behavior of two steel was relatively similar, where the steel with better performance demonstrated an increase in the {223} component also known as &#947;'. The study through finite elements shows that the more requested region of the part has forming predominated for stretching. Finally the best distribution of the deformations in the part produced with steel of higher coefficient of train hardening is shown. Concluding the work allowed the evaluation of influences of the skin pass on the rolling of steel of low carbon content in the mechanical properties of the steel and the result of this mechanical behavior in the adopted part. Also it allowed to evaluate the evolution of the crystallographic texture of two steel chosen before and after.

This article develops a novel methodological framework to investigate the exposure of eco- nomic systems to the risk of physical capital stranding. Combining Input-Output (IO) and network theory, we define measures to identify both the sectors likely to trigger relevant capital stranding cascades and those most exposed to capital stranding risk. We show how, in a sample of ten European countries, mining is among the sectors with the highest external asset strand- ing multipliers. The sectors most affected by capital stranding triggered by decarbonisation include electricity and gas; coke and refined petroleum products; basic metals; and transporta- tion. From these sectors, stranding would frequently cascade down to chemicals; metal products; motor vehicles water and waste services; wholesale and retail trade; and public administration. Finally, we provide an estimate for the lower-bound amount of assets at risk of transition-related stranding, which is in the range of 0.6-8.2% of the overall productive capital stock for our sample of countries, mainly concentrated in the electricity and gas sector, manufacturing, and mining. These results confirm the systemic relevance of transition-related risks on European societies. / Series: Ecological Economic Papers

São realizadas análises teóricas e experimentais do atrito nos processos de forjamento a frio, através do ensaio de compressão do anel. Os modelos de atrito de Amonton-Coulomb (μ), atrito interfacial (m) e de Levanov (f) são investigados com auxílio de softwares comerciais de simulação de processos de forjamento. Diferentes condições de lubrificação foram aplicadas para o aço baixa liga 16MnCr5 e a liga de alumínio AA6351 nas condições recozido e encruado. O atrito foi analisado, utilizando os softwares MSC.Superforge e Qform, em função dos resultados obtidos e as condições de lubrificação e estado do material. Valores paramétricos do atrito adquiridos através de correlação teórico-experimental são condizentes com a literatura, indicando a relação do atrito com o material de trabalho, inclusive com seu grau de encruamento. Os modelos de atrito m e f apresentaram maior sensibilidade com relação ao estado do material. / Experimental and theoretical analyses of friction in cold forging process are evaluated by means of the ring compression test. Friction models from Amonton- Coulomb (μ), interfacial friction (m) and Levanov’s model (f) are investigated by aid of numerical simulation software. Different lubricants are applied for low carbon steel alloy 16MnCr5 under annealed and work-hardened conditions. Friction is analyzed by means of lubricant and material conditions using MSC.Superforge and Qform numerical simulation softwares. Acquired frictional parameter values obtained by theoretical-experimental correlation agree with literature, showing friction’s relationship with workpiece material and its hardening level. Friction models m and f presented better sensitivity when concerning the material’s hardening level.

The ability for domestic consumers to provide demand response to dynamic electricity pricing will become increasingly valuable for integrating the high penetrations of renewables that are expected to be connected to electricity networks in the future. The aim of this thesis is to investigate whether domestic consumers will be willing and able to provide demand response in such low-carbon futures. A broad approach is presented in this thesis, with research contributions on subjects including data privacy, behavioural economics, and battery modelling. The principle argument of the thesis is that studying the behaviour of consumers with grid-connected photovoltaic ('PV') systems can provide insight into how consumers might respond to dynamic pricing in future low-carbon power systems, as both experience irregular electricity prices that are correlated with intermittent renewable generation. Through a combination of statistical and qualitative methods, this thesis investigates the demand response behaviour of consumers with PV systems in the UK. The results demonstrate that these consumers exhibit demand response behaviour by increasing demand during the day and decreasing demand during the evening. Furthermore, this effect is more pronounced on days with higher irradiance. The results are novel in three ways. First, they provide quantified evidence that suggests that domestic consumers with PV systems engage in demand response behaviour. Second, they provide evidence of domestic consumers responding to irregular electricity prices that are correlated with intermittent renewable generation, thereby addressing the aim of this thesis, and supporting the assumption that consumers can be expected to respond to dynamic pricing in future markets with high penetrations of renewables. Third, they provide evidence of domestic consumers responding to dynamic pricing that is similar to real-time pricing, while prior evidence of this is rare and confined to the USA.