Browsing by Issue Date, starting with "2023-09"
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- Adaptation to climate change in cities of Mediterranean EuropePublication . Pietrapertosa, Filomena; Olazabal, Marta; Simoes, Sofia; Salvia, Monica; Fokaides, Paris; Ioannou, Byron I.; Viguie, Vincent; Spyridaki, Niki-Artemis; Hurtado, Sonia De Gregorio; Geneletti, Davide; Heidrich, Oliver; Tardieu, Léa; Feliu, Efren; Rižnar, Klavdija; Matosović, Marko; Balzan, Mario V.; Flamos, Alexandros; Sel, Natasa Belsak; Reckien, DianaABSTRACT: Cities across Mediterranean Europe face common climatic threats. They are highly vulnerable and very likely to suffer losses and damages due to heat waves, droughts, wildfires, landslides, and extreme coastal events. To this date, however, there is no systematic understanding of how cities in Mediterranean Europe are preparing to adapt to these impacts. To address this question, we analyse local adaptation plans in 73 cities located in 51 regions across 9 European countries along the Mediterranean Sea (France, Italy, Spain, Greece, Portugal, Croatia, Slovenia, Cyprus and Malta). We also investigate upper levels of planning to understand the influence of policy environments. Across the sample, 67 % of regions have adopted a plan, but only 30 % of the cities. The most common climate-related hazards these cities prepare for are extreme temperatures and rainfall, followed by drought and water scarcity, as well as floods and landslides. Without legal obligations, neither regional nor national adaptation policy frameworks seem to influence the development of urban plans. In some cases, cities are ahead of national policy. This paper sheds light on the progress of local adaptation planning in Mediterranean Europe and paves the way for further research in this climate-threatened geographical area.
- Aerogel cathodes for electrochemical CO2 reduction [Comunicação oral]Publication . Messias, Sofia; Fialho, Maria T.; Paninho, A. B.; Branco, Luis C; Nunes, A. V. M.; Martins, Rodrigo; Mendes, Manuel Joao; Nunes, D.; Rangel, C. M.; Machado, AnaABSTRACT: Electrochemical reduction of carbon dioxide powered by renewable energy to produce fuels and chemicals is a technology with potential to contribute to an economy based on a carbon neutral cycle. The development of cost effective, highly active and stable catalysts for CO2 electroreduction is being intensively researched. This work addresses the development of aerogel supported copper-zinc bimetallic catalysts[1]. Aerogels are substances with exceptional properties with many current and potential applications [2-3]. Due to their high surface area, stability in corresponding gaseous or liquid phases, transport through large meso and macropores they are especially suited as catalysts and carrier materials for catalysis and, when electric conductive for electro-catalysis. Aerogels prepared by the sol gel method and impregnated with metallic particles will be tested as cathodes for the co-electrolysis of CO2 and water to produce syngas at temperatures near room temperature and high-pressure. In this way this process can be directly coupled to other high pressure processes, such as Fischer-Tropsch that use high pressure syngas as raw material. Productivities and faradaic efficiencies will be evaluated. The characterization of the aerogel-based cathodes will be undertaken by surface analysis techniques. BET surface areas will be determined. The catalytic cathodes will be tested in an ionic liquid-based electrolyte as a way to increase current densities, due to the high CO2 solubilities exhibited by some ionic liquid families.
- Sub-Bandgap Sensitization of Perovskite Semiconductors via Colloidal Quantum Dots IncorporationPublication . Ribeiro, Guilherme; Ferreira, G.; Menda, U.D.; Alexandre, Miguel; Brites, Maria João; Barreiros, M. Alexandra; Jana, S.; Águas, Hugo; Martins, Rodrigo; Fernandes, P.A.; Salomé, P.M.P.; Mendes, M.J.ABSTRACT: By taking advantage of the outstanding intrinsic optoelectronic properties of perovskite-based photovoltaic materials, together with the strong near-infrared (NIR) absorption and electronic confinement in PbS quantum dots (QDs), sub-bandgap photocurrent generation is possible, opening the way for solar cell efficiencies surpassing the classical limits. The present study shows an effective methodology for the inclusion of high densities of colloidal PbS QDs in a MAPbI3 (methylammonium lead iodide) perovskite matrix as a means to enhance the spectral window of photon absorption of the perovskite host film and allow photocurrent production below its bandgap. The QDs were introduced in the perovskite matrix in different sizes and concentrations to study the formation of quantum-confined levels within the host bandgap and the potential formation of a delocalized intermediate mini-band (IB). Pronounced sub-bandgap (in NIR) absorption was optically confirmed with the introduction of QDs in the perovskite. The consequent photocurrent generation was demonstrated via photoconductivity measurements, which indicated IB establishment in the films. Despite verifying the reduced crystallinity of the MAPbI3 matrix with a higher concentration and size of the embedded QDs, the nanostructured films showed pronounced enhancement (above 10-fold) in NIR absorption and consequent photocurrent generation at photon energies below the perovskite bandgap.
- Marginal soils for bioenergy production : How to identify these soils in Portugal?Publication . Abreu, Mariana; Reis, Alberto; Fernando, Ana LuisaABSTRACT: n the bioenergy/biorefineries sector, energy crops have achieved a relevant position as a feedstock for bio-based products, biofuels and bioenergy. To produce the energy crops, soils with low Indirect Land Use Change (ILUC) risk must be utilized, such as marginal/degraded/contaminated (MDC) soils. Locating these types of soils in any territory, region, or country is challenging. Several criteria, e.g. soil drainage, dryness, temperature, have been identified by the European Union, and allow to classify soils as marginal. Yet, the dispersed information makes the identification and selection of marginal soils a challenging process. Therefore, this study details the tools and baseline documents that can be used to identify marginal areas, presenting low ILUC risk for the cultivation of energy crops. The application of the methodology to Continental Portugal allowed to obtain a preliminary map that indicates available soils for the cultivation of energy crops.
- Quality-assurance of heat-flow data: The new structure and evaluation scheme of the IHFC Global Heat Flow DatabasePublication . Fuchs, Sven; Norden, Ben; Neumann, Florian; Kaul, Norbert; Tanaka, Akiko; Kukkonen, Ilmo T.; Pascal, Christophe; Christiansen, Rodolfo; Gola, Gianluca; Safanda, Jan; Espinoza-Ojeda, Orlando Miguel; Marzan, Ignacio; Rybach, Ladislaus; Balkan-Pazvantoglu, Elif; Ramalho, Elsa; Dedecek, Petr; Negrete-Aranda, Raquel; Balling, Niels; Poort, Jeffrey; Wang, Yibo; Joeleht, Argo; Rajver, Dusan; Gao, Xiang; Liu, Shaowen; Harris, Robert; Richards, Maria; Mclaren, Sandra; Chiozzi, Paolo; Nunn, Jeffrey; Madon, Mazlan; Beardsmore, Graeme; Funnell, Rob; Duerrast, Helmut; Jennings, Samuel; Elger, Kirsten; Pauselli, Cristina; Verdoya, MassimoABSTRACT: Since 1963, the International Heat Flow Commission has been fostering the compilation of the Global Heat Flow Database to provide reliable heat-flow data. Over time, techniques and methodologies evolved, calling for a reorganization of the database structure and for a reassessment of stored heat-flow data. Here, we provide the results of a collaborative, community-driven approach to set-up a new, quality-approved global heat-flow database. We present background information on how heat-flow is determined and how this important ther-mal parameter could be systematically evaluated. The latter requires appropriate documentation of metadata to allow the application of a consistent evaluation scheme. The knowledge of basic data (name and coordinates of the site, depth range of temperature measurements, etc.), details on temperature and thermal-conductivity data and possible perturbing effects need to be given. The proposed heat-flow quality evaluation scheme can discriminate between different quality aspects affecting heat flow: numerical uncertainties, methodological uncertainties, and environmental effects. The resulting quality codes allow the evaluation of every stored heat -flow data entry. If mandatory basic data are missing, the entry is marked accordingly. In cases where more than one heat-flow determination is presented for one specific site, and all of them are considered for the site, the poorest evaluation score is inherited to the site level. The required data and the proposed scheme are presented in this paper. Due to the requirements of the newly developed evaluation scheme, the database structure as presented in 2021 has been updated and is available in the appendix of this paper. The new quality scheme will allow a comprehensible evaluation of the stored heat-flow data for the first time.
- New triazine-phosphonate dopants for proton exchange membranes (PEM) [Poster]Publication . Teixeira, Fatima; Teixeira, António P. S.; Rangel, C. M.ABSTRACT: The establishment of a new paradigm for energy is underway demanding new energy sources for the increasing needs of society with none or lower environmental impact. To reach the ambitious and well defined targets for decarbonized energy systems it is needed new clean technologies. Some of them rely on well-established or emerging electrochemical devices, including batteries, fuel cells and CO2 and water electrolysers, whose applications and performances depend on key components such as their separators/ion-exchange membranes.1,2 The most studied and already commercialized membranes go by the brand name of Nafion, which showed great chemical stability, but their high proton conduction depends on their water content, markedly limiting their operating temperature range. Our previous studies have demonstrated that the incorporation of aryl or heterocyclic phosphonic acid dopants into Nafion, by casting, results in an enhancement of the proton conductivity1-4 and stability5 of the Nafion doped membranes.
- Mapping municipal solid waste to boost circular valorization practices in ŁódzkiePublication . Moura, Patrícia; Eusebio, Ana; Patinha, Pedro; Quental, Lídia; Lukasik, Rafal M.ABSTRACT: Geographic Information System (GIS) is a powerful instrument that can be used for the spatial representation of waste and by-product flows at various levels, allowing to improve municipal solid waste (MSW) management. The mapping obtained can be advantageously targeted to build a regional network of technological, economic, social and environmental linkages and to boost circular economy practices. In this work, the data on MSW produced in the Łódzkie region, Poland, during 2021 were used to generate a geolocalized database and an interactive web map, using ArcGIS software. The geodatabase and the map visualization were organized in three layers of information with increasing detail to foster a map-driven symbiosis between waste suppliers and waste recipients, paving the way for a more circular regional economy.
- Materials, resources, and CO2 impacts of building new renewable power plants to reach EU's goals of carbon neutralityPublication . Simoes, Sofia; Lima, Ana TeresaABSTRACT: The European Union's low carbon power plants installed capacity needs to increase by 90% by 2030. Using a spreadsheet model, we calculate the total amounts of construction materials (henceforth materials) and natural resources (henceforth resources) used for the new renewable and nuclear power plants. Considering concrete, glass, and steel as materials and sand and water as resources, future CO2e impacts are estimated using 2010-2020 as a reference. To test if circular economy measures reduce the effects of materials and resource consumption, we derive three near-future scenarios for the decade 2020-2030: business as usual (BAU), EU manufacture (EUM), and circular (CIRC). Independent of the scenario, CO2e emissions double from increasing low-carbon power plants. Circular economy substantially lowers resource consumption but not carbon emissions. With 90% recycling (CIRC), we spare 90% sand and 5% water compared to a BAU scenario. Resource-efficient power plant design and major technological advancement in recycling processes are needed to fulfill a CIRC scenario.
- Diversification strategies and the emergence of a new industrial value-chain: challenges and opportunities for companiesPublication . Sousa, Cristina; Fontes, Margarida; Conceição, OscarinaABSTRACT: Marine renewable energy technologies (MRET) can contribute to the decarbonization of energy, as well as to the revitalisation of other sectors, but are still an emerging and uncertain area. The development of these technologies entails the construction of a new industrial value chain, requiring the involvement of established firms from a variety of industries. Thus, it is important to understand how established firms can be mobilised to support MRET development, by pursuing diversification strategies. This paper addresses this question by looking at the case of Portuguese firms that expressed willingness to engage with MRET and investigating how they perceive the opportunities for diversification into the new business area, the changes they may need to introduce in their resources and capabilities to exploit those opportunities, and the obstacles they expect to face.
- Solar Resource and Energy Demand for Autonomous Solar Cooking Photovoltaic Systems in Kenya and RwandaPublication . Cardoso, João P.; Couto, António; Costa, Paula; Rodrigues, Carlos; Facão, Jorge; Loureiro, David; Wambugu, Anne; Banda, Sandra; Da Silva, Izael; Simões, TeresaABSTRACT: The challenges associated with traditional cooking methods in African countries, particularly the use of firewood and charcoal, which have negative impacts on the environment, health and human and economic development and safety, are addressed in this work. Given the high annual solar irradiation on the African continent, photovoltaic-powered electric cooking alternatives, such as electric pressure cookers (EPCs), are identified as a potential efficient, clean and affordable cooking solution. This work focuses on the potential of standalone solar electric cookers for use in rural African locations, namely, if this type of solution can satisfy cooking demand. Surveys and experimental data from several households in two different countries (Rwanda and Kenya) were collected. Specifically, the researchers performed a survey regarding cooking habits and an experimental campaign to determine real energy consumption profiles of EPCs. The main results are analyzed and discussed in this work. An assessment of the solar power capability to directly supply the EPCs’ energy demand, as determined from the experimental data, is performed. The findings indicate that, for the most commonly prepared food types, using EPCs saves considerable time in comparison with traditional cooking methods. In Rwanda, time savings range from 55% to 84%, while in Kenya, the time saved varies from 9% to 64%. Results show that, even for scenarios with high installed solar capacity, storage solutions are required to enable the PV-powered EPC system to supply more than 50% of meal demand.