Percorrer por autor "Nogueira, Teresa"
A mostrar 1 - 10 de 40
Resultados por página
Opções de ordenação
- An heuristic approach for optimal location of gas supply units in transportation systemPublication . Nogueira, Teresa; Mendes, Rui; Vale, Zita; Cardoso, JoséThe best places to locate the Gas Supply Units (GSUs) on a natural gas systems and their optimal allocation to loads are the key factors to organize an efficient upstream gas infrastructure. The number of GSUs and their optimal location in a gas network is a decision problem that can be formulated as a linear programming problem. Our emphasis is on the formulation and use of a suitable location model, reflecting real-world operations and constraints of a natural gas system. This paper presents a heuristic model, based on lagrangean approach, developed for finding the optimal GSUs location on a natural gas network, minimizing expenses and maximizing throughput and security of supply.The location model is applied to the Iberian high pressure natural gas network, a system modelised with 65 demand nodes. These nodes are linked by physical and virtual pipelines – road trucks with gas in liquefied form. The location model result shows the best places to locate, with the optimal demand allocation and the most economical gas transport mode: by pipeline or by road truck.
- Avaliação do Impacto dos Veículos Elétricos na Qualidade de Serviço da RedePublication . Alarcón, Celia Monja; Nogueira, TeresaO forte incremento nos veículos elétricos e suas necessidades de carregamento têm acarretado grandes desafios à gestão da rede de distribuição, nomeadamente, na alteração da sua qualidade de serviço. Este artigo propõe uma metodologia para avaliar o impacto de diferentes modos de carregamento numa rede residencial duma cidade espanhola. Trata-se duma rede em BT com 8087 consumidores, para a qual foram simulados diferentes cenários de funcionamento e foram analisados os valores apresentados para quatro variáveis críticas. Os índices de qualidade resultantes são comparados com os limites padrão fixados pela norma de referência EN50160. Constatou-se que, na generalidade, a concentração dos modos de carregamento nos parques de estacionamento leva a piores índices de qualidade de serviço, sendo determinado o modo de carregamento mais conveniente para cada localização. Foi também verificado que o desequilíbrio de tensão é a variável mais influenciada pela localização dos modos de carregamento.
- Bacterial cooperation controlled by mobile elements: kin selection and infectivity are part of the same processPublication . Rankin, D. J.; Mc Ginty, S. E.; Nogueira, Teresa; Touchon, M.; Taddei, F.; Rocha, E. P. C.; Brown, S. P.
- Baterias de Iões de Lítio, a chave da Eletrificação AutomóvelPublication . Fragoso, Henrique; Nogueira, TeresaA mobilidade da sociedade do século XXI levanta questões de sustentabilidade energética, tanto a nível da produção de energia como do seu armazenamento. As baterias de iões - lítio são um dos sistemas de armazenamento químico de energia mais relevantes da atualidade com aplicação nos mais diversos dispositivos elétricos e eletrónicos e, recentemente, nos veículos elétricos e híbridos. Comparativamente a outros sistemas, estas baterias destacam-se por serem leves e com elevado potencial elétrico, entre outras caraterísticas vantajosas que se descrevem. Neste artigo são apresentadas e comparadas 3 tecnologias de baterias de iões de lítio utilizadas na indústria automóvel, com uma reflexão sobre as necessidades tecnológicas a desenvolver nos próximos anos.
- Conceção de um sistema fotovoltaico híbrido: térmico e elétricoPublication . Maurício, José; Nogueira, TeresaO rendimento dos painéis fotovoltaicos decresce com o aumento da temperatura de funcionamento, aspeto particularmente relevante em locais onde a temperatura diária máxima atinge temperaturas elevadas, como é o caso de Portugal. Este facto tem implicações no dimensionamento de um painel fotovoltaico, desde a fase de projeto no cálculo das correntes e tensões de operação dos equipamentos a jusante do painel, até à sua operação, com influência relevante nas condições económicas de exploração. Um rendimento elétrico inferior implica mais tempo para amortizar o painel, resultando num projeto de investimento menos atrativo. Este estudo propõe a conceção de um sistema de arrefecimento térmico do painel, com base na circulação forçada de água, sendo apresentados benefícios que justificam a sua exploração. A utilização do princípio de extração do calor pode ser integrada com sistemas de aquecimento de águas (painéis solares) existentes nos edifícios, permitindo diluir os custos da solução e aumentar o rendimento global elétrico e térmico através de um pré-aquecimento.
- Consideration of Sustainability in Projects: A Cross-Sectional Quantitative AnalysisPublication . Magano, José; Silvius, Gilbert; Nogueira, Teresa; Hamed, Farzad; Nogueira, Teresa; Carmenado, IgnacioThe consideration of sustainability in projects is one of the most critical global trends in project management today, as projects are instrumental in the sustainable development of organisations and society. In the growing literature on this topic, most studies take a qualitative approach, often based on single case studies, and quantitative studies are underrepresented. To address these limitations, this study aims to examine the extent to which different aspects and perspectives of sustainability are integrated into projects by reporting a quantitative analysis of the consideration of sustainability in 134 projects. The analysis used the Sustainable Project Management Maturity Model SPM3 to analyse the level at which sustainability was considered in the projects. The results show that, on average, sustainability is considered at a reactive level, with the desired levels of consideration on average one level higher (proactive). When considering the different triple bottom line perspectives, the economic perspective scores highest, followed by the social and environmental perspectives. The study also shows that building-related projects score higher on sustainability considerations than other project types, as do larger projects. Limitations of the study include its European focus, the relatively small sample size, and the fact that the data was collected in different locations over a four-year period, which raises the possibility of subjective differences in the evaluation of individual projects. Nevertheless, the study can be seen as a ‘wake-up call’ for project practitioners, who need to be more proactive in this regard if projects are to be the route to sustainability.
- Data Management Plan: Deliverable D1.1. Relatório para o Projeto SHOREWINNERPublication . Nogueira, Teresa[excerpt from the text] The SHOREWINNER project aims to create a community of practice for Southern European offshore wind energy by partnering with five Centers of Vocational Excellence (CoVEs) from Portugal, Spain, Italy, Greece, and Cyprus. The main goals are to assess offshore resources in these countries, share best practices and knowledge, develop skills, and provide training to align with European objectives and priorities.
- Eco-Friendly Ester Fluid for Power Transformers versus Mineral Oil: Design ConsiderationsPublication . Nogueira, Teresa; Beleza Carvalho, José António; Magano, JoséMineral oil has long been used as an adequate coolant and dielectric medium in power transformer design. However, it is flammable and environmentally risky as it may be leaked or spilled. Therefore, ester fluids, which have been increasingly used in the last two decades, look promising as an ideal dielectric option. This research aims to better understand how using ester fluid insulation in power transformers impacts their physical and electrical dimensions, including their load-losses, impedance, masses, and equipment dimensions. Three case studies were carried out in a Portuguese electrical equipment manufacturer’s facility, with varying electrical parameters and physical properties of the mineral oil and ester-filled power transformers. The main results enhanced the known good electrical behavior of ester fluids, namely creating a lower electric field around winding wedges, yet the use of ester fluids led to higher load-losses, larger masses, additional radiators and, consequently, higher manufacturing costs. Nevertheless, the contribution of ester-filled power transformers to the improved environmental safety (reducing spillage and fire risks), among other advantages, makes ester fluids a truly eco-friendly option for power transformer design.
- Electric vehicles growth until 2030: Impact on the distribution network powerPublication . Nogueira, Teresa; Sousa, Ezequiel; Alves, Gustavo R.In the coming years, we will witness a change in the current car fleet sales, from traditional fuel engines towards electrical vehicles (EVs), particularly passenger light-duty vehicles. They plug into the grid and store the electricity in rechargeable batteries; therefore, the widespread adoption of EVs will bring many challenges for the distribution network. Forecasting the impact of EVs on distribution networks is a difficult task given the uncertainty on the potential evolution of their sales. This study forecasts the EVs sales growth for the 2020–2030 decade in 3 possible evolution scenarios, carried out for a given Portuguese regional area. The demanded energy for charging the batteries was estimated, considering one long and one short route. The analysis was applied to three EVs models: Nissan Leaf, Tesla Model 3, and Renault Zoe. Their impacts on the rated power of the distribution network are calculated for the three scenarios, and the results are presented, standing out the insufficient power at peak hours.
- Energy storage for renewable energy integration: the case of Madeira Island, PortugalPublication . Miguel, Miguel; Nogueira, Teresa; Martins, FlorindaEnergy storage has become a crucial issue regarding renewable energy management, even more important in an island system with the inherent fluctuating operation and inaccurate energy forecast. The growth of decentralized generation in an isolated electrical grid means load stability problems and requires energy storage as a potential solution to guarantee safety and reliability standards. The study described in this paper highlights the need to store energy in Madeira island system and evaluate theoperational power dispatch with the introduction of batteries. A simulation tool was developed to quantify the impact of batteries in wind and thermal power plants technologies.