ER - Comunicações em actas de encontros científicos internacionais
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- On the Integration of Hydrogen in multipurpose wave energy platformsPublication . Mourão, Guilherme; Portillo, Juan C. C.ABSTRACT: his work presents an integrated numerical modelling approach implemented in Modelica language, which combines a multipurpose wave energy floating platform made of multiple oscillating water columns and the production and storage of green hydrogen in the same platform. The modelling approach comprised the simulation of the platform in WAMIT from which the hydrodynamic coefficients were obtained that serve as input for the integrated model implemented in Modelica. The Cherry Library for electrolysis processes and new modules developed in this work for storage were used and coupled to a model for the five-oscillating-water-column floating platform. The optimisation of hydrogen production based on hydrodynamic performance and energy conversion from waves off the coast of Portugal was conducted to identify optimal green hydrogen production parameters. The operational performance of the system was studied in detail for four representative days of the seasons to estimate optimal production of green hydrogen from ocean waves under those conditions. Dispatch of hydrogen and its conversion to other sustainable fuels, such as methanol or Ammonia are also discussed in terms of the total levelised cost of hydrogen (LCOH). A new tool developed at the National Laboratory for Energy and Geology was implemented to estimate costs. Results are still under progress.
- Experimental investigation of a novel wave energy floating platform for hybrid wind-wave applications: The OctaPlatPublication . Mendonça, Nuno P.; Portillo, Juan C. C.ABSTRACT: The work presents the process of model design and testing and the experimental results for the OctaPlat, a new wave energy floating platform, conceived at IST/ULisboa. A physical model was designed on the basis of the Octaplat concept, which comprises five oscillating water columns (OWCs). The physical model design considered only three of the five OWCs due to infrastructure constraints and was made of acrylic material on a scale of 1:100th scale. The experimental campaign comprised free decay tests and tests under both regular and irregular wave conditions. Different power take-off systems for OWCs (impulse air turbines) were approximated through small orifices. Parameters such as RAO, dimensionless pressure, and the capture width ratio (CWR) were determined and analysed to understand the model performance under different conditions. Under regular waves, the results showed that the coupled hydrodynamic interaction between pitch and surge motions mainly affects the chambers located at the outer edges of the platform. Furthermore, the RAOs of the OWCs seem to be influenced by the natural coupled heave frequency, the natural frequencies of OWC1 and OWC3, and possibly the submultiple of the coupled heave natural frequency (k=1.5). Results also show that the different orifice plates considerably affect the CWR and the peaks' frequencies of its maximum values. Under irregular waves considering full-scale values, for a 2.5 m significant wave height, the peak pneumatic power reached 1.6 MW at 0.077 Hz with an equivalent rotor air turbine diameter of 6.3 m (that is, 30 mm orifice diameter) and 1.9 MW at 0.083 Hz with an equivalent rotor air turbine diameter of approximately 4 m (i.e., 20 mm orifice diameter). For a significant wave height of 3.4 m, the 30 mm orifice produced 3.6 MW at 0.077 Hz, while the 20 mm orifice reached 3.8 MW at 0.091 Hz. These results confirm the platform's feasibility for megawatt-scale wave energy conversion, supporting a key claim of this technology. The experimental results were compared with the numerical ones in terms of CWR. Good agreement was found between both, with a coefficient of determination (R^2) of about 0.94, and the relative difference between them was always less than 20%, except for a few peak deviations.
- Numerical investigation of a novel hybrid wind-wave system and its variable pneumatic chamber volume controlPublication . Marreiros, João; Portillo, Juan C. C.ABSTRACT: This work presents a numerical investigation of a novel control system for a new hybrid wave-wind energy floating platform. It comprises the design of a control system for controlling the variable pneumatic chamber volumes coupled with the hydrodynamics of the floating platform to maximise wave power production. The numerical model is developed in the object-oriented non-casual language Modelica, for which a new module for the control system was integrated into an existing package developed at IST/ULisboa. A sensitivity analysis of the main control parameters in terms of techno-economic parameters is performed and analysed. Results show that the envelope of control parameters’ values for increasing conversion efficiencies and power production is narrow, and an increase of about 30% was achieved with the best case compared with the base case. Moreover, it was observed that the variable volume of the pneumatic chambers shows significant variations on a part of the operational periods typical of the west of Portugal.
- New Greenhouse Gas simulation and mapping tools to support local carbon neutrality agendas: application to the city of AlmadaPublication . Amorim, Filipa; Simoes, Sofia; Barbosa, Juliana; Oliveira, Paula; Trindade, Paula; Aelenei, Laura Elena; Catarino, Justina; Viana, Susana; Figueiredo, LeonorABSTRACT: The aim of this work is to develop three innovative decision support tools: (1) a scenario tool that enables users to interactively design scenarios of activity variables that support decarbonisation trajectories on a local scale; (2) a mitigation tool that translates scenarios into greenhouse gas (GHG) emissions, taking into account the identification and prioritisation of the most innovative, cost-effective mitigation options (technological and behavioural) for Portuguese municipalities; and (3) a mapping tool to identify GHG emissions ‘hot spots’ on a local scale. In the first phase, these tools are applied and tested for the case study of the city of Almada in support of the ‘Agenda for a Carbon Neutral Almada by 2050’. These tools will also contribute to the training and involvement of local stakeholders, to improve the design of local GHG emissions mitigation strategies and roadmap. In the second phase, these tools will be further developed so they can be used in other Portuguese municipalities.
- European policies on Circular Economy and Climate Mitigation: synergies or antagonisms?Publication . Trindade, Paula; Barbosa, Juliana; Amorim, Filipa; Simoes, Sofia; Lima, Ana TeresaABSTRACT: The main objective of this paper is to review policy goals, measures and instruments across the following policy areas: climate, energy; environment (including CE) and industry. This review's objective is twofold: (1) to assess and characterise synergies and antagonisms among policy domains regarding CE and climate mitigation, and (2) to identify innovative and effective policy approaches for integrating CE into climate action. The analysis will focus on the EU+ policy level, with some incursions at Member State level (+UK) for the cases where best practices in integrating CE policies are identified. The policies assessment will feed into the climate mitigation scenarios for circular construction.
- How the quality of urban adaptation plans in Europe has evolved over time: indication of progress? Judgement by way of an assessment frameworkPublication . Reckien, Diana; Buzási, Attila; Olazabal, Marta; Spyridaki, Niki-Artemis; Eckersley, Peter; Simoes, Sofia; Salvia, Monica; Pietrapertosa, Filomena; Fokaides, ParisABSTRACT: Since the Paris Agreement, there has been an increasing focus on assessing the progress of climate change adaptation across multiple sectors and regions (Lesnikowski et al., 2017; Tompkins et al., 2018; Berrang-Ford et al., 2019). An important question is what ‘progress’ means and how it could be assessed, at the international, national, and local levels. Hitherto, there is a wealth of information on climate responses at sub-national levels (Hale et al., 2021). Cities and urban areas are increasingly recognized as important actors in climate response (Sanchez Rodriguez et al., 2018). In urban adaptation studies, most assessments focus on tracking and analysing policy outputs, such as approved adaptation plans (Castan Broto et al., 2020; Dodman et al., 2022). Analysing plans cannot tell the whole story in terms of actual progress in the collective reduction (or redistribution) of climate risks. However, it can provide information about the quality and relevance of adaptation processes and actions, and help to assess the likelihood that cities’ advance adaptation goals by reducing risks and increasing resilience equitably (Olazabal et al., 2019; Woodruff & Stults, 2016). Scholars have argued that ‘the best method to ensuring robust adaptation is to ensure rigorous adaptation planning processes’ (Preston et al., 2011).
- Design for Sustainability Tools: Categories of Classification Towards Practical UsePublication . Vicente, José; Camocho, DavidABSTRACT: Since the emergence of early approaches to design for the environment (such as green design or ecodesign), several tools have been developed to support the design process in the integration of environmental, social and, more recently in a comprehensive way, sustainability and circularity criteria. The vast quantity and diversity of tools have required the creation of ways to organize and classify them to facilitate their identification, selection and use by designers, engineers, and other product development professionals, according to the needs of the design practice objectives, and the specificities of the project. This paper aims to analyze the existing knowledge regarding design for sustainability and circularity tools to identify the main categories used to classify these tools. This was done with the aim of synthesizing the most appropriate classification from the point of view of the product designer who will use the tools. To achieve this, the methodology of literature review was employed, which included scientific papers, theses, and reference books in the field. This analysis gathered a wide diversity of classification forms and organized them into 6 overarching categories. It was also possible to verify that certain forms of classification are not particularly relevant for designers when selecting a tool, as they don’t clarify the feasibility of applying the tool. It is possible to conclude that there is still a need for homogenization and consensus in academia regarding the best way to classify these tools so that the classification is scientifically sound and useful for designers.
- Are "Smart Cities” also “Climate Smart”? An Assessment of the EU Mission “Climate-Neutral and Smart Cities”Publication . Salvia, Monica; Pietrapertosa, Filomena; Maestosi, Paola Clerici; Simoes, Sofia; Reckien, DianaABSTRACT: Urbanization and the concentration of energy-consuming economic activities make cities responsible for more than 70% of global greenhouse gas emissions. At the same time, cities are becoming increasingly vulnerable to climate change impacts. The EU Mission “Climate-Neutral and Smart Cities”, recently launched a call for starting a pathway towards “100 climate-neutral and smart cities by 2030”. The list of 336 candidate cities (86% from the EU-27 and 14% from associated or negotiating countries) was published in February 2022. The cities constitute a very large and diverse sample that was used to conduct this timely research to identify the main factors that can drive and support a smart and sustainable transition of urban areas. A critical analysis of the main achievements in five main driving factors (local climate planning, climate emergency declaration, participation in networks, international projects and competitions) provides insights on the main factors driving cities towards climate smart actions. Results show that 76% of the cities have a local climate, in 82% of cases developed under the Global Covenant of Mayors for Climate and Energy, which involves about 75% of the candidate cities. URBACT is the most popular funding programme, with 23% of cities involved in at least one funded project. The five selected driving factors seem to capture fairly well the level of "activism" of the sample cities in pursuing smart and climate-related projects and initiatives (15 of the 16 cities that have initiatives and activities in their background that fall into all five sets of the Venn diagram are among the 112 cities selected in this first phase of Mission 100 CNSC). 90% of the sample cities are part of at least one Transnational Municipal Network, which is the most important influencing factor, among the five analysed, for cities applying for this Mission. The original results of this timely study can be useful to decision-makers at all levels, but especially to other cities, to enhance knowledge on steps to be taken to accelerate the transition to carbon neutrality. Moreover, the rich dataset made available by this research represents an important knowledge base not only for future monitoring of the selected cities' progress during the implementation phases, but also for the desired replication effects in other urban areas.
- Simulated hydropower production under climate change scenarios at Torrão reservoir, in northern PortugalPublication . Diogo, Paulo; Mujtaba, Babar; Beça, Pedro; Simoes, Sofia; Fortes, Patricia; Amorim, FilipaABSTRACT: Climate conditions have a significant impact on energy demand and production. The project CLIM2POWER, completed in 2021, aimed to develop a climate service at European scale for the planning of the power infrastructures operations using seasonal forecasts and long-term climate projections. This work presents part of the project, and focus on assessing the climate change impacts on hydropower production of Torrão Dam. Torrão reservoir is located on the Tâmega river, a tributary of the Douro river in northern Portugal. The long-term (2016-2100) climate data used is obtained from the EURO-CORDEX simulations, on a daily time scale. Two different combinations of regional and global climate models for scenarios RCP 4.5 and 8.5 (four combinations) were used: ICHEC-EC-EARTH-CLMcom-CCLM4 (CCLM4) and ICHEC-EC-EARTH-DMI-HIRHAM5 (HIRMAM5). Long-term precipitation data was bias-corrected using the multiplicative shift method, and for rainfall-runoff simulation, HEC-HMS model was used. The results showed that 30-years total annual precipitation for future periods (i.e, 2016-2040, 2041-2070 and 2071-2100) was 3.4%-28.1% lower than the historical one. 30-years annual total discharges of all future periods decreased for both models and RCPs (1.2%-30.2% less than the historical ones). Regarding future 30-year annual average capacity factors, there was reduction (1.8%-24.8%) with respect to historical one, except in two future periods for CCLM4 model of RCP 4.5 scenario i.e., 1.2% increased in the period 2016-2040 and 1.5% increased in the period 1971-2100. This suggest that hydropower production is not only dependent on future precipitation trends but also on the hydropower production procedures.
- Competing water uses between agriculture and energy: Quantifying the future impacts of climate change for the Portuguese power sectorPublication . Fortes, Patricia; Simoes, Sofia; Brás, Teresa; Amorim, FilipaABSTRACT: This paper analyses to which extent the competition for water resources between water demand for agriculture and hydropower may affect the future Portuguese carbon-neutral power sector under RCP8.5 climate scenario. Climate change effects on the availability of wind, solar PV and electricity demand are also modelled by the energy system eTIMES_PT model. Results show that, by 2050, Portuguese irrigation water demand is projected to increase between 3.5%-9.7% and 19% in Douro watershed, responsible for more than 50% of the national hydropower production. Consequently, annual average hydropower capacity factor reduces around 9-10%. Comparing with historical average hydrological years, climate change can lead to a reduction of hydropower production between -9% to -30%, which may be aggravated to -21% to -39%, with water competition. This reduction is compensated with a rise of Offshore Wind less affected by climate change.
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