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Novel approach to location planning of hydrogen refueling stations: How market drivers and existing infrastructure impact the hydrogen economy
No full textABSTRACT: This study aims to present a novel methodology to assess future potential location of hydrogen refueling stations (HRS), involving geospatial and levelized costs of hydrogen (LCOH) analyses. This methodology entails five stages and was developed and applied to mainland Portugal. It can be used in other regions or countries. In this study, a total of 708 potential locations for different HRS were identified and studied for five scenarios. The results indicate that LCOH varies between a minimum of 6.5 €/kg H and a maximum of 11.2 €/kg H. Moreover, 3 574 routes were analyzed considering four hydrogen production sites and the five scenarios, of which 2 395, or 67% of the routes, have a LCOH of between 6 - 9 €/kg H. The main conclusions of the study indicate that there are significant regional disparities in Portugal and that the adoption of hydrogen as an alternative fuel still presents challenges, especially in regions with limited hydrogen refueling infrastructure. The uneven distribution of hydrogen infrastructure and the high associated costs are likely to further exacerbate these economic and technological disparities. Addressing these imbalances requires the development of regional strategies that encourage, for example, hydrogen production in remote and underserved regions.Portuguese Programme of Recovery and Resilience (02/C05-i01/2022) through the Moving2Neutrality Mobilizing Agenda (Project 32), WP3 P3.3
New data on the palynostratigraphy and paleoenvironments of the late Miocene (Tortonian) Quifangondo Formation in the Cabo Ledo section, Kwanza Basin, Angola
No full textABSTRACT: A detailed palynostratigraphic and palynofacies analysis, associated with a lithological control, was carried out on eleven outcrop samples from the Quifangondo Formation in the Cabo Ledo (Petrofina) section, Kwanza Basin, Angola. The samples yield relatively diverse and well-preserved terrestrial and marine palynomorphs. A systematic analysis of the samples enables the identification of nine spore genera and 3 species, 20 pollen genera and 13 species, and 32 dinoflagellate cyst genera and 34 species. In addition, 10 genera of other aquatic palynomorphs, such as Chlorophyceae green algae, are identified. Dinoflagellate cysts and other aquatic palynomorphs typically dominate throughout the assemblages. In this section, a combined pollen - dinoflagellate cyst zonation is used to define two palynoassociations. The first palynoassociation is middle Tortonian in age and is characterized by the presence of the pollen grain Fenestrites spinosus and the first occurrence of the dinoflagellate cyst species Selenopemphix armageddonensis. Additionally, diverse Chlorophyceae green algae dominate most of this interval samples. The second palynoassociation is assigned to the late Tortonian and is characterized by a drastic decrease in Chlorophyceae green algae, as opposed to the gonyaulacales dinoflagellate cysts. The first occurrence of the pollen grain Fenestrites longispinosus marks the transition between the palynoassociations. Lithologically, the Cabo Ledo (Petrofina) section is dominated by a claystone with an increase in the silt and carbonate components towards the upper section. The lithological data, integrated with palynostratigraphy and palynofacies, suggests that the upper part of the Quifangondo Formation was mainly deposited in an inner to middle neritic environment characterized by dysoxic conditions punctuated by periods of terrestrial inflows. Such conditions typically result from seasonal fluctuations. The age and depositional environment of the upper Quifangondo Formation inferred from this new data allows a correlation with the other Quifangondo sequences previously studied by the authors. This multi-proxy approach is important for further stratigraphic analysis with other age-controlled lithostratigraphic units in the basin. Furthermore, the improvement of paleoenvironmental and depositional models for this unit is of great importance for cross-basin correlation and future petroleum exploration plays.info:eu-repo/semantics/publishedVersio
Are "Smart Cities” also “Climate Smart”? An Assessment of the EU Mission “Climate-Neutral and Smart Cities”
Full text linkABSTRACT: 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.N/
Assessing the industrial effects of the deployment of renewable energy technologies: when product identity matters
No full textABSTRACT: Investment in renewable energy technologies (RET) produces impacts on economic activity and job creation that are fundamental to increase the social acceptability of those technologies. Previous research that attempted to measure the impacts of RET has mainly focused on its effects in energy production and climate mitigation, but surprisingly little is known about the potential of RET to transform the industrial structure of an economy. This paper proposes a methodology to understand and measure the industrial transformative impact of RET. The paper draws on contributions from the sustainability transitions literature and from the economic literature that analyses the socioeconomic impacts of RET, and combine them with the economic complexity literature in order to address two main gaps: the lack of measurement of industrial transformative effects in the first; and the assumption of product homogeneity in the second that precludes an assessment of more structural impacts. We develop a conceptual approach to the way technology deployment can lead to changes in the industrial structure, centered on the notion of product heterogeneity intrinsic to the economic complexity literature. We advance three main dimensions along which to measure the changes in the industrial
structure driven by modifications in the basket of products being produced due to the development of the technology value chain: sophistication, connectivity, and competitiveness. We also propose a more precise delineation of the industrial value chain of the technology, by considering the actual weights of each sector to the technology and the technology to each sector. This approach is applied to the case of wind energy in Portugal (a successful fast follower), compared with three other main wind energy producers (Spain, Denmark, Germany). The results show a strong relationship between the deployment of the technology and the sophistication and the competitiveness of the Æcloud of productsÆ composing the industrial value chain. The paper proposes a novel analytical framework and measurement tools that can support a timely assessment of the effects of sustainable energy technologies in the industrial structure, with relevance for policy.N/
New C-3 Substituted 1H- and 2H-Indazolephosphonic Acid Regioisomers: Synthesis, Spectroscopic Characterization and X-Ray Diffraction Studies
No full textABSTRACT: Indazole is known as an important structural motif in medicinal chemistry and, recently, has also gained attention in other areas, such as materials chemistry, with many studies showing different potential applications for their regioisomers. Phosphonates are also a class of compounds with diverse applications, ranging from medicinal to material applications. Here we present the synthesis of 1H- and 2H-indazolephosphonic acid derivatives substituted at C-3, involving mono- or bisphosphonic acids, from their corresponding carboxylic acid and esters. These compounds were fully characterized, and their spectroscopic data were evaluated to identify and distinguish the structural scaffold of each phosphonic acid. Crystallization of [hydroxy(1-methyl-1H-indazol-3-yl)methanediyl]bis(phosphonic acid) 7 afforded crystals suitable for single crystal X-ray diffraction studies and its crystal structure details are also discussed.info:eu-repo/semantics/publishedVersio
Unit Sizing and Feasibility Analysis of Green Hydrogen Storage Utilizing Excess Energy for Energy Islands
No full textABSTRACT: This study examines whether green hydrogen production using combined wind and solar energy on Marmara Island can meet the island's electricity demand and fuel the fuel needs of a hydrogen-powered ferry. A hybrid system consisting of a 10 MW wind farm, a 3 MW solar PV system, and a PEM electrolyzer sized to meet the island's hydrogen demand was modeled for the island, located in the southwestern Sea of Marmara. The hydrogen production potential, energy flows, and techno-economic performance were evaluated using HOMER-Pro 3.18.4 version. According to the simulation results, the hybrid system generates approximately 62.6 GWh of electricity annually, achieving an 82.8% renewable energy share. A significant portion of the produced energy is transferred to the electrolyzer, producing approximately 729 tons of green hydrogen annually. The economic analysis demonstrates that the system is financially viable, with a net present cost of USD 61.53 million and a levelized energy cost of USD 0.175/kWh. Additionally, the design has the potential to reduce approximately 2637 tons of CO2 emissions over a 25-year period. The results demonstrate that integrating renewable energy sources with hydrogen production can provide a cost-effective and low-carbon solution for isolated communities such as islands, strengthening energy independence and supporting sustainable transportation options. It has been demonstrated that hydrogen produced by PEM electrolyzers powered by excess energy from the hybrid system could provide a reliable fuel source for hydrogen-fueled ferries operating between Marmara Island and the mainland. Overall, the findings indicate that pairing renewable energy generation with hydrogen production offers a realistic pathway for islands seeking cleaner transportation options and greater energy independence
Alteração hidrotermal ácido-sulfato associada aos jazigos de sulfuretos maciços de Lagoa Salgada, Caveira, Lousal, Aljustrel e São Domingos (Faixa Piritosa Ibérica)
No full textTese de doutoramento, Geologia (Metalogenia), Universidade de Lisboa, Faculdade de Ciências, 2021RESUMO: A Faixa Piritosa Ibérica é caracterizada por dezenas de jazigos de sulfuretos maciços formados no Famenniano e Tournaisiano em ambiente marinho pela circulação de fluidos hidrotermais através das rochas vulcânicas e sedimentares encaixantes. O seu enquadramento geológico decorre do evento hidrotermal e de processos posteriores como metamorfismo regional, deformação varisca e tardi-varisca e, em alguns casos, exumação, erosão e alteração supergénica. Nos 7 jazigos estudados - Lagoa Salgada, Caveira, Lousal, Algares, São João, São Domingos e Chança, definem-se as seguintes fases de veios de alunite: a) gerados em período sin/tardi-Varisco em deformação dúctil/semi-dúctil e associados a corredores estruturais com cisalhamento - I (paralelos a S1), IIa (oblíquos a S1) e IIb (redes deformadas), sendo a paragénese marcada por alunite/natroalunite ± pirite ± minamiite ± wavellite e acompanhada por argilização precoce (caulinite ± greenalite), apresentando estes veios estrutura em pente, dobramento e génese anterior ou coeva da clivagem S2; b) formados em fases tardi-variscas/eoalpinas/alpinas semi-frágéis/frágeis, com textura porcelanosa e matriz homogénea com pseudocubos de alunite - IIb (redes com veios sub-horizontais) e III (em falhas desligamento) e IV (fraturas irregulares). Em contexto supergénico ocorrem a jarosite e natrojarosite. Não existe uma relação direta entre a argilização supergénica e os veios de alunite I, IIa, IIb e III. A alteração ácido-sulfato foi marcada pela circulação de fluidos muito ácidos e oxidantes, de baixa temperatura, por um período de tempo geológico significativo. O modelo metalogenético infere uma evolução contínua. A caracterização dos chapéus de ferro nos jazigos estudados reflete o seu zonamento: topo com texturas terrosas e cavidades por erosão/dissolução/precipitação; zonas basais mais compactas e maciças, que transitam a muro a níveis de enriquecimento supergénico e, inferiormente, a mineralização primária. Identificaram-se também depósitos coluviais e brechas de preenchimento. A cartografia desenvolvida sobre a alteração ácidosulfato, argilização e oxidação constitui um vetor de prospeção mineral indicador das mineralizações de sulfuretos da Faixa Piritosa.ABSTRACT: Iberian Pyrite Belt (IPB) is characterized by dozens of massive sulfide deposits formed during Famennian and Tournaisian times in a marine environment by the circulation of hydrothermal fluids through the host volcanic and sedimentary rocks. Its geological setting is complex, resulting from the hydrothermal event and subsequent processes such as regional metamorphism, deformation (Variscan to Alpine) and, in some cases, exhumation, erosion and supergenic alteration. It was possible to identify different phases of alunite veins in the seven deposits investigated - Lagoa Salgada, Caveira, Lousal, Algares, São João, São Domingos and Chança: a) formed in the sin-/tardi-Variscan period in ductile/semi-ductile deformation associated with shear structural corridors - I (parallel to S1), IIa (oblique to S1) and IIb (deformed networks) defined by alunite/natroalunite ± pyrite ± minamiite ± wavellite being accompanied by early clay alteration (kaolinite ± greenalite) and common comb structure and folding being formed before or coeval to the S2 cleavage; b) formed in late-Variscan/eo-Alpine/Alpine semi-fragile/fragile systems - IIb (networks with subhorizontal veins), III (in strike-slip faults) and IV (irregular fractures), defined by porcelanous texture and alunite pseudocubes. Jarosite and natrojarosite occur in the supergene environment. There is no direct relationship between supergene clay alteration and the alunite I, IIa, IIb and III veins. Acidsulfate alteration is defined by low temperature acidic and oxidizing fluids, for a large geological time period considering a metallogenetic continuous evolution. The characterization of the gossans at the studied deposits made it possible to understand their zoning: top with earthy textures and cavities by erosion/dissolution/precipitation; more compact and massive basal zones, which gradually pass downward to supergene enrichment levels and to the primary mineralization. Colluvial deposits and filling breccias were also identified. The mapping developed on the acid-sulfate, clay and supergene oxidation hydrothermal systems, supported by detail stratigraphy, can be used as an efficient prospecting method focused on the IPB sulphide mineralization.N/
Identificação de áreas salinas em zonas húmidas com recurso a índices espetrais e dados geoquímicos. O caso do Baixo Vouga Lagunar (Aveiro, Portugal)
No full textABSTRACT: The Baixo Vouga Lagoon (BVL) is an important wetland on the Portuguese coastal continent that has been suffering from the destruction of its agricultural fields due to saline intrusion processes. The aim of the research was to identify areas of salinity combining geochemical data and spectral indices obtained from Sentinel 2B satellite images. The methodology was developed using images from July 2023 and February 2024, with samples taken during the same seasonal period. Fourteen spectral indices were calculated: four vegetation indices and ten salinity indices. Pearson's method was used to assess the correlation between geochemical data and the spectral indices. The Canopy Response Salinity Index (CRSI) and Salinity Index 1 (SI 1) showed the highest correlation, at 0.428 and 0.516 respectively. Despite the limitations of using optical sensor in flooded areas, the spectral response of halophyte vegetation in areas of higher salinity was crucial for its differentiation and primary delimitation of the most affected areas.RESUMO: A região do Baixo Vouga Lagunar (BVL) é uma importante zona húmida do continente costeiro português que tem sofrido com o problema da destruição dos seus campos agrícolas, devido a processos de intrusão salina. O objetivo de pesquisa foi identificar áreas de salinidade através da combinação de dados geoquímicos e índices espetrais obtidos através de imagens do sistema de satélite Sentinel 2B. A metodologia foi desenvolvida utilizando imagens referentes aos meses de julho de 2023 e fevereiro de 2024, estando as amostras situadas no mesmo período sazonal. Foram calculados catorze índices espetrais a partir das imagens de satélite: quatro índices de vegetação e dez índices de salinidade. O método de Pearson foi usado para avaliar a correlação entre os dados geoquímicos e os índices espetrais. O Índice de Resposta do Dossel à Salinidade (CRSI) e o índice de salinidade SI 1 foram os que apresentaram maior correlação, na ordem de 0,428 e 0,516, respetivamente. Apesar das limitações do uso de sensores óticos em áreas inundadas, a resposta espectral da vegetação halófita, presente nas áreas de maior salinidade, foi crucial para a sua diferenciação e delimitação primária das zonas mais afetadas
Improving bio-oil fractions through fractional condensation of pyrolysis vapors from Eucalyptus globulus biomass residues in a prototype auger reactor
No full textABSTRACT: Bio-oil produced from the pyrolysis of lignocellulosic biomass has potential as a biofuel or chemical precursor. However, its valorization is hindered by its complex composition, high water concentration, and the presence of oxygenated compounds. Operational strategies are therefore required to improve its quality. This study evaluated the technical feasibility of fractional condensation as an alternative to conventional single-stage condensation of vapors produced from pyrolysis of residual Eucalyptus globulus biomass to collect bio-oil fractions with improved properties. The process was carried out using a prototype-scale auger reactor with continuous operation. The fractional condensation system comprised four sequential condensation stages operating at progressively lower temperatures: 140, 100, 80, and 0 degrees C. The collected bio-oil fractions were analyzed in terms of product yields, water separation efficiency, elemental composition, heating value, and the presence of volatile and semi-volatile compounds. The results demonstrated that fractional condensation achieved total bio-oil yields comparable to those obtained with the single-stage condensation system, while enabling the recovery of bio-oil fractions with lower water concentration, higher carbon concentration and increased heating value. Notably, the first condensation stage collected heavy fractions with water concentration between 3 % and 6 %wt., oxygen concentration between 17 % and 21 %wt., and carbon concentration between 69 % and 72 %wt., resulting in O/C molar ratios between 0.17 and 0.22, values close to those of biodiesel. These fractions exhibited lower heating values of up to 31 MJ/kg, surpassing those of conventional liquid biofuels such as biomethanol and bioethanol. These findings highlight the potential of fractional condensation of pyrolysis vapors from residual biomass from Eucalyptus globulus as an effective strategy to produce bio-oil with properties more suitable for direct energy use or as an intermediate feedstock for biofuels synthesis. Further research is recommended to optimize the condensation stages and assess the long-term stability of recovered fractions