Repositório do LNEG
Repositório Científico do Laboratório Nacional de Energia e Geologia
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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.
Vida e obra de Jorge Cândido Berkeley Cotter (1845-1919)
Publication . Pacheco, Marta; Cachao, Mario
RESUMO: Assinalaram-se recentemente os 180 anos do nascimento do geólogo português de ascendência irlandesa, Jorge Cândido Berkeley Cotter (1845-1919), figura que marcou a Geologia de Portugal, nomeadamente através dos seus estudos estratigráficos e paleontológicos, sobretudo no que se refere ao Miocénico português. O presente artigo desvenda um pouco da sua relativamente desconhecida personalidade, desde as suas origens até aos seus múltiplos e versáteis trabalhos que se estendem para além da Geologia, um trabalho que permanece relevante actualmente. Com uma prolífera carreira, Berkeley Cotter dedicou-se à Geologia e à Paleontologia, e até ao ensino e divulgação da língua inglesa, tendo também trabalhado como Secretário de Estado. Foi ainda responsável pela recolha de inúmeros exemplares paleontológicos que integram, entre outros, as coleções do Museu Geológico de Lisboa.
Portuguese historical palaeobotanical collections reveal a new species of late Palaeozoic marattialean fern
Publication . Correia, Pedro; Šimunek, Zbynek; Pereira, Zélia
ABSTRACT: A new Late Pennsylvanian marattialean species, Cyathocarpus felicianoi sp. nov., is described and illustrated from the Douro Carboniferous Basin, northwestern Portugal, from Stephanian C (upper Gzhelian, Upper Pennsylvanian) deposits. The studied fossil material is composed of penultimate and ultimate sterile ‘pecopterid’ frond fragments preserved as adpressions and belongs to the Carlos Teixeira's collection, an invaluable palaeobotanical collection from the Portuguese geological surveys. The description of this new fern fossil-species based on historical palaeobotanical collections, highlights the importance of natural history collections for the advancement of science, especially regarding the knowledge about diversity and richness of marattialean ferns of Euramerican Carboniferous.