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Mapping Critical Raw Materials (CRM) hard rock deposits in Europe
Publication . Albert, Capucine; Bertrand, Guillaume; Berthier, Hervé; de Oliveira, Daniel Pipa Soares; Tulstrup, Jørgen
ABSTRACT: This article presents the new version of the map of critical raw materials hard rock deposits that has been produced in the frame of the GSEU project (Geological Service for Europe). The map displays over 800 medium to very large deposits for 30 Critical Raw Materials (CRM) from the 2023 list of the European Commission, in 33 European countries. We explain the objective of this work and the process and methodology for collecting, compiling and harmonizing CRM data from multiple providers. We also describe the map itself, the information it carries and its availability. As an example of added-value output, we present a pan-European assessment of CRM potential, classified in 4 categories of confidence from “historical or non-compliant resource estimates” to “mineral reserves”. This assessment provides an image of the current known potential for CRM in Europe. Based on this exercise, we discuss the challenges and barriers of compiling and harmonizing mineral resources data at continental scale, and the future perspectives of this work we envision through the EGDI (European Geological Data Infrastructure). We also discuss the limitations of the map and dataset to raise awareness on their proper interpretation and use.
Systematic review on social acceptance of mining in the context of the energy transition
Publication . Santos, Elaine; Simoes, Sofia
ABSTRACT: This technical report presents a systematic review of the scientific literature on the social acceptance of mining in the context of the energy transition. The analysis covered 118 publications from 1998 to 2025 in English, Portuguese, and Spanish, integrating quantitative and qualitative methods. The results show the growth of the field (7.47% per year) and reveal the following central factors for social acceptance: community participation, transparency, procedural justice, institutional trust, and conflict management. Regional differences were identified: in Europe, the emphasis falls on governance and transparency, whereas in Latin America socio-environmental justice, conflicts, and expectations prevail. Despite the centrality of critical minerals for the energy transition, few studies explicitly articulate both themes. The report proposes recommendations for policymakers, companies, and communities, aiming at more participatory practices. This is the first LNEG study on this topic, contributing to public policies and institutional strategies in the mining sector.
Optimizing Chlorella vulgaris production and exploring its impact on germination through microalga-N2-fixing bacteria consortia
Publication . Sanchez-Zurano, Ana; Vilaro-Cos, Silvia; Figueiredo, Daniel; Melkonyan, Lusine; Ferreira, Alice; Acien Fernandez, F. Gabriel; Lafarga, Tomás; Gouveia, Luisa
ABSTRACT: Microalgal biomass is increasingly valued in industrial and agricultural sectors due to its bioactive compounds. However, large-scale production remains costly, mainly due to nitrogen fertilizer expenses. A promising sustainable alternative is co-cultivation with N2-fixing bacteria, capable of supplying biologically available nitrogen. In this study, Chlorella vulgaris was grown in synthetic medium with and without nitrogen, as well as in co-culture with three different N2-fixing bacteria in nitrogen-free medium. Microalgal growth was assessed by dry weight, Fv/Fm ratio, and flow cytometry, which also allowed evaluation of population dynamics and cell viability. Biomass composition (proteins, carbohydrates, lipids, chlorophyll, and carotenoids) was analyzed under all conditions. Co-cultures in nitrogen-free medium showed comparable biomass productivity to nitrogen-supplemented controls, although Fv/Fm values indicated physiological stress in some cases. Moreover, the agricultural potential of the resulting biomass and supernatants was evaluated through germination bioassays using lettuce seeds. All cultures tested at 0.2 g & sdot;L-1 significantly improved the germination index. Also, applying the culture supernatant (biomass removed) also yielded positive effects, with GI increases exceeding 40 %. These results suggest that co-cultivation with N2-fixing bacteria can support efficient microalgal production while generating biomass and supernatants with biostimulant potential, contributing to sustainable agriculture and circular bioeconomy strategies.
Determination of reflectance of interest from limited state-of-the-art solar reflector field soiling measurements
Publication . Wette, Johannes; Sutter, Florian; Cunha Diamantino, Teresa; Montecchi, Marco; Bern, Gregor; Fernández-García, Aránzazu
ABSTRACT: In concentrated solar thermal technologies, plant operators usually monitor the soiling of their solar field with handheld reflectometers. These measurements can be used for yield calculations and to adapt cleaning strategies: if the reflectometer reading falls below an empirically established threshold, the solar field should be cleaned. There are several commercial reflectometers available for this purpose, but all of them measure at different combinations of wavelength, acceptance angle or incidence angle. It is the purpose of this study to bring the readings from all main commercial reflectometers to the same representative value, enabling their comparison with one another and the translation of these readings into a meaningful reflectance parameter. Thus, different handheld reflectometers are correlated with a laboratory reflectometer, capable of measuring in the whole solar spectral region, covering a wide range of incidence and acceptance angles. The most significant parameter is the near-specular solar-weighted reflectance, measured at the typical incidence and acceptance angles for a given plant, as it is the most precise parameter to describe the reflected energy from the solar field. The correlations for all included reflectometers, show highly linear correlations over a wide range of soiling levels with low deviations. Consequently, the correlations presented herein enable the plant operators at the studied site to compute the near-specular solar-weighted reflectance from their reflectometer readings. and, with that, increase the significance of the measurements without collecting any additional data. The work also establishes a detailed procedure to derive this type of correlations at any site of interest.
Como o trabalho do LNEG apoia a concretização do PNEC: Plano Nacional de Energia e Clima - Conheça 10 dos trabalhos do LNEG que contribuem para a concretização do PNEC
Publication . Simoes, Sofia; Simões, Teresa; Barbosa, Juliana Pacheco; Rodrigues, Carlos; Azevedo, Pedro; Cardoso, João; Facão, Jorge; Costa, Paula Silva; Justino, Paulo Alexandre; Gírio, Francisco; Reis, Alberto; Passarinho, Paula; Duarte, Luís; Moura, Patrícia; Abreu, Mariana; Estanqueiro, Ana; Couto, António; Oliveira, Paula; Quental, Lídia; Patinha, Pedro; Catarino, Justina; Picado, Ana; Ramalho, Elsa; de Oliveira, Daniel Pipa Soares; Filipe, Augusto; Albardeiro, Luís; Santos, Sara; Gonçalves, Pedro