Repositório do LNEG
Repositório Científico do Laboratório Nacional de Energia e Geologia
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The palynology of the Upper Triassic-Lower Jurassic in the Algarve and Lusitanian basins, Portugal
Publication . Vilas Boas, Margarida; Cirilli, Simonetta; Pereira, Zélia; Duarte, Luis; Fernandes, Paulo
ABSTRACT: High-resolution palynological analyses from the Algarve and Lusitanian basins (Portugal) provide a refined biostratigraphical framework and palaeoenvironmental reconstruction for the Late Triassic-Early Jurassic transition. In the Algarve Basin, three new palynozones (AT, SC, and CP) characterise the Silves Group from the early Carnian to early Hettangian, documenting the first Iberian occurrence of Tulesporites briscoensis and precisely delineating the Triassic-Jurassic Boundary (TJB). In the Lusitanian Basin, three palynozones (CG, IK, and Pm) constrain the Conraria and Pereiros formations to the Norian-Hettangian, with the TJB located at the base of the Pereiros Formation. Palaeoenvironmental reconstructions reveal distinct basin-specific evolutions. The Algarve Basin records an early transition from fluvial (Silves Sandstones) to marginal-marine (lagoonal and pond) settings, evidenced by abundant upper Carnian algal elements and reworked Neoproterozoic algae. Conversely, the Lusitanian Basin reflects a Norian-Hettangian marginal-marine, river-dominated setting, with microforaminiferal linings at the base of the Pereiros Formation marking the earliest marine transgression in the Lusitanian Basin. Quantitatively, both basins show a persistent dominance of xerophytic taxa, indicating a shift toward warmer, seasonally dry conditions across the TJB. Malformed sporomorphs in both records suggest environmental stress potentially linked to Central Atlantic Magmatic Province (CAMP) activity. Comparative analysis reveals that sedimentation initiated earlier in the Algarve (early Carnian) than in the Lusitanian Basin (Norian), suggesting diachronous development during Pangaea breakup. The assemblages show strong affinities with the Onslow Microflora, highlighting the Portuguese margin as a key archive for western Tethyan floral and climatic evolution.
Framework of Initial Selection of Offshore Energy Island Location for Sustainable Water Desalination
Publication . Almasoudi, Muhnad; Sharifi, Soroosh; Glumac, Anina; Simões, Teresa; Hemida, Hassan
ABSTRACT: In this paper, a framework for the selection of an energy island location to supply power for water desalination plants with cleaner and more sustainable energy has been developed. The developed framework aims to evaluate the feasibility of creating offshore energy islands and select its location by considering factors such as renewable energy potential, site suitability, marine traffic, future developments, and proximity to desalination facilities. The energy and water data have been collected from available published data on marine traffic, water desalination production and government reports. Solar power data were obtained from the Ministry of Natural Resources via RETScreen, wave data were sourced from Windguru, and wind power data were obtained from both sources. The data were used for the Inverse Distance Weighting (IDW) interpolation and Multi-Criteria Decision Analysis (MCDA) to develop the framework. The developed framework has been utilized to develop an energy Island in the Red Sea to power the water desalination plants along the KSA west shore. The findings demonstrate the significant potential of energy islands to partly mitigate Carbon Dioxide (CO2) emissions from desalination plants, advancing global efforts toward water sustainability and supporting long-term goals for achieving net-zero emissions. The study also emphasizes the importance of further research into wave energy in the Red Sea, as the lack of real-time data and comprehensive resources limits accurate assessments.
Assessing energy, thermal and visual performance of photochromic glazing: From spectrophotometric characterization to building simulations
Publication . Teixeira, Henriqueta; Moret Rodrigues, António; Aelenei, Daniel; Gomes, Maria da Glória
ABSTRACT: Photochromic (PC) glazing is a promising smart glazing solution for enhancing buildings energy efficiency and indoor comfort through its ability to dynamically adjust its optical properties in response to solar radiation. However, studies assessing the global (energy, thermal and visual) performance of this technology are scarce. This work evaluates the performance of a clear double glazing incorporating a PC film. Spectrophotometric tests were first conducted to determine the thermal and optical properties of the PC film, revealing a dynamic visible transmittance and a low UV and near-infrared transmittance. Subsequently, a previously calibrated dynamic simulation model of an office room was used to assess the impact of the PC film on energy consumption (climatization energy needs and energy use considering an ideal air-conditioning system) and indoor comfort (in accordance with useful daylight illuminance, daylight glare index, predicted mean vote, adaptive thermal comfort model and Portuguese legislation) during working hours (9am-6 pm of weekdays) across the climates of three European cities (Lisbon, Berlin and London). The results show that PC glazing can reduce cooling demand in all studied climates. Total energy use decreased by up to 10% in the warmest of the studied climates, while slight increases were observed in the colder climates. Visual comfort improved significantly, with up to 24% and 74% more working hours with useful illuminance and imperceptible glare levels, respectively. Thermal comfort analysis revealed a negligible change in free-float conditions during working hours, and an improvement of up to 20% when the HVAC system was operating.
Circular economy modelling for climate change mitigation: A review of empirical evidence and modelling approaches
Publication . Zanon Zotin, Marianne; Fortes, Patricia; Corbier, Darius; Deetman, Sebastiaan; Edelenbosch, Oreane; van Engelenburg, Martijn; Hauenstein, Christian; Hertwich, Edgar; Jiang, Meng; von Köckritz, Luja; Magalar, Leticia; Pauliuk, Stefan; Straub, Lucas; Vélez-Henao, Johan; van Vuuren, Detlef
ABSTRACT: Circular economy (CE) measures can play a role in reducing greenhouse gas (GHG) emissions, especially in material- and energy-intensive sectors. Yet, their representation in GHG mitigation pathways is still not well captured in climate change mitigation models. To support modelling efforts towards better CE representation, two reviews were conducted: (1) the empirical evidence on the GHG mitigation potential of CE strategies across material supply and demand sectors and R-strategies, and (2) the current modelling approaches used to assess these strategies. Findings show that, while most studies focus on recycling, increasing attention is given to upstream strategies such as material substitution, design for reuse, and service-based business models. Important gaps remain, particularly around Refuse, Rethink, behavioural factors, rebound effects, as well as synergies and trade-offs with climate policy. Industrial ecology methods provide a detailed material flows representation but lack feedback mechanisms and economic dynamics. In contrast, GHG mitigation models offer broader system coverage but often simplify materials and CE dynamics. Better alignment between methods is needed, including shared definitions, improved data, and more collaboration across modelling communities. Strengthening the modelling of CE strategies can support policy-relevant assessments of CE’s contribution to achieving global climate goals.
A Strategy to Improve Porous MOF Structural Stability for the Effective Removal of S/N Pollutants from (Bio)fuels
Publication . Silva, Dinis; Mirante, Fátima; Santos-Vieira, Isabel; Granadeiro, Carlos; Silva, Luis Cunha; Balula, Salete S.
ABSTRACT: The need to mitigate environmental pollution drives the continuous quest for advanced desulfurization and denitrogenation methods in refineries. The presence of sulfur and nitrogen compounds in fossil fuels and biofuels contributes largely to atmospheric polllution. Oxidative catalysis presents a promising way for addressing these challenges, offering efficient and environmental friendly pathways. This work investigates the heterogeneous catalytic performance of the polyoxometalates, plenary Keggin PW12 structure and the derivative lacunary PW11 structure, supported on the porous MIL-100(Fe) metal-organic framework, for simultaneous oxidative desulfurization and denitrogenation. Both PW11@MIL-100(Fe) and PW12@MIL-100(Fe) catalysts demonstrated rapid and complete desulfurization within 60 min of reaction using a sustainable H2O2 oxidant. Remarkably, PW11@MIL-100(Fe) exhibited higher catalytic efficiency and demonstrated high recycle capacity. In fact, notable results were attained to remove the most noxious pollutants in (bio)fuels, offering insights for the development of effective catalytic materials with high viability for the energy industry.