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Portugal faces water scarcity challenges, yet studies on per-household water consumption are limited. This study aims to address this gap by employing cluster analyses to assess how population trajectories, a previously overlooked aspect, and the regional location influence per-household monthly water consumption across 122 municipalities. Findings highlight higher consumption in the South despite lower prices. Municipalities experiencing population growth and those with long-term population declines show higher per-household water consumption but lower prices. Interestingly, while higher prices correlate with lower consumption, southern municipalities show increased prices without reduced consumption. Clustering reveals slight changes in consumption patterns from 2011 to 2020.

Rising temperatures, increasingly frequent extreme weather events and sea level rise are playing a growing role in shaping displacement, rural-urban migration, circular movements but also voluntary and forced immobilities. The debate on climate mobilities – the interplay between climate change and human mobility – is currently moving centre stage in migration studies. Migration theory, on the other hand, does not necessarily reflect sufficiently on the role of the environment in mobility patterns. Including an understanding of the complex nature of climate mobilities avoids assuming climate change related mobility as new or exceptional per se, and offers understanding of the plural, multi-causal, and political ways in which climate change and human im/mobilities intersect.

Electrochemical CO2 reduction (CO2RR) is one of the most promising methods for decreasing the concentration of CO2, meanwhile, converting them into the high value-added chemicals, which has been more and more investigated and developed recently. Imidazolium ionic liquids (ILs) have been widely used as electrolytes in CO2RR and shown satisfactory performance. While the function of ILs is still unclear. Besides, the economic feasibility and potential of CO2RR with ILs-based electrolytes as well as the environmental effects are also unclear. Therefore, this work focuses on the technology evaluation and exploration for CO2RR-to-CO with ILs-based electrolyte. Firstly, a literature review about CO2RR to CO, CH4, CH3OH, and syngas (H2/CO=1:1 and 1:2) in ILs-based electrolytes was conducted. Then the processes to obtain these C1-products were analyzed from both economic and environmental aspects based on the state-of-the-art technology and the rationally hypothetical future cases. The results show that CO is the most valuable product considering both the economic benefits and environmental impact, which will be more lucrative in the future with the improvement of CO2RR performance. Then, based on 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]), a series of imidazolium ILs with various proton in the group (-CH3, -CH3OH and -SH, noted as [BMMIM][PF6], [BMOHIM][PF6] and [BMSHIM][PF6], respectively) at C2 site of the imidazole ring were synthesized and used as electrolyte to perform CO2RR over a commercial Ag foil. As a result, the more inert the active proton, the more favorable for the production of CO. Notably, nearly 100% CO was obtained when [BMMIM][PF6] with the most inert proton. This confirms that the C2-H of the imidazole ring has an important influence on CO2RR performance and may be involved in the reaction. Finally, [BMMIM][PF6] and [BMIM][PF6] were selected as the electrolytes to conduct CO2RR over a bimetallic catalyst. As a result, the product from 99.69% HCOOH switched into 98.85% CO only via changing the electrolyte from [BMIM][PF6] into [BMMIM][PF6]. Mechanistic studies reveal that the CO2 adsorption configuration on the surface of the catalyst was altered when switching to another IL with a different CO2 active site, resulting in two distinct pathways for the generation of HCOOH and CO, respectively. 

Abstract: This study evaluates the economic and environmental benefits of implementing the proposed REcovered Nitrogen from manURE (RENURE) criteria as mineral fertiliser into the Nitrates Directive (ND) to facilitate the utilisation of minerals from manure. Implementing the RENURE amendment could significantly contribute to sustainability goals in an economic way, offering a 4.8 % reduction in economic costs in livestock-dense regions including Brittany (-0.7 %), Lombardy (-2.3 %), Flanders (-2.6 %), Lower Saxony (-4.7 %), Catalonia (-4.8 %), North-Rhine Westphalia (-4.8 %), and the Netherlands (-5.0 %). Through spatially explicit multi-agent modeling, the study revealed that the RENURE amendment not only promises economic benefits, but also enhances nitrogen circularity by 1.3 % and reduces greenhouse gas emissions by 6 % in these areas. These findings highlight the potential of nutrient recovery and reuse under RENURE to address both economic and environmental challenges, supporting the European Union's (EU) Farm-to-Fork strategy (F2F) goals of reducing nutrient emissions to the air and fertilizer use.

The high expansion rate of renewable generation in the last years was mainly driven by the green transition and the net zero emission targets for 2050. Concerns on the volatility of wind and solar energy, can be mitigated by combining these renewable energy sources with energy storage and operating them coordinately, creating hybrid power plants. Price of batteries has also dropped significantly reaching US$139/kWh in 2023 (battery pack price) and it is expected that by the end of this decade the price will fall below US$100/kWh. Thus, more developers and owners of large renewable plants are looking into their hybridization for both off-grid and grid-connected configurations. The advantages for such a hybrid renewable power plant include complementarity of energy production, better utilization of grid connection while reducing the connection costs, firm capacity of energy production, increase of revenue streams by providing ancillary services, etc. However, the control of a wide range of technologies i.e. wind turbines, solar PV and batteries, from different suppliers poses challenges during their integration into a hybrid power plant.This paper aims to provide an overview of the most common configurations of co-located hybrid power plants including their control architectures. The advantages and challenges for each configuration are discussed in detail from the perspective of OEMs and system integrators.The work presented is part of the ongoing activities in the IEA Wind TCP Task 50 on Hybrid Power Plants that aims to provide a systematic framework and guidelines in this area.

Optimal power flow (OPF) plays a crucial role in addressing asymmetric operational problems of bipolar direct current distribution networks (DCDNs). However, the effectiveness of existing OPF models applied to bipolar DCDNs exhibits sensitivity to the problem type, underlying assumptions, and choice of objective functions. Hence, this paper proposes a dynamic decoupling-based convex-concave programming (CCP) framework to formulate an OPF model, aiming for a more rational impact across diverse applications in asymmetric operational bipolar DCDNs. More specifically, the coupled power between poles and ports of bipolar DCDNs is analyzed in detail, leading to the derivation of decoupled pole-to-ground equivalent circuits without relying on any preliminary assumption. Subsequently, the OPF problem of the equivalent circuits is formulated via CCP, involving the introduction of a cutting plane through difference-of-convex inequalities to limit the feasible region of the traditional OPF based on second-order cone programming, thereby diminishing dependence on exact relaxation conditions. Finally, a solution method is proposed to dynamically correct both the decoupled equivalent circuits and the cutting plane. The numerical results indicate that this method effectively addresses power optimization problems with a non-strictly monotonic objective function. Furthermore, it exhibits scalability, showcasing its applicability to large-scale radial bipolar DCDNs.

Periglacial alluvial fans are common in northwestern and central Europe and their pre-Holocene stratigraphic records typically date back to late Middle Pleniglacial and Late Pleniglacial (late MIS3 and 2). Preserved stratigraphic records that include an entire interglacial-glacial cycle have, so far, not been described and it is thus unknown how periglacial alluvial fans responded during a full cycle of interglacial-glacial climate changes. In this paper, we reconstruct the evolution of the Eerbeek periglacial alluvial fan in the Netherlands which was deposited during the late Saalian (MIS 6) to late Weichselian (MIS 2) period, including the entire last interglacial–glacial cycle (MIS 5-2). Our reconstruction is based on 48, up-to 45-m deep borehole and Cone Penetration Test (CPT) logs that allowed the construction of an 8-km long longitudinal and a 7-km long transverse cross section over the Eerbeek periglacial alluvial fan. Age control was provided by means of 17, previously published, Optically Stimulated Luminescence ages of two boreholes on the fan, and 14 14C ages from three boreholes and a nearby, now abandoned, quarry.Overlying a thick, late Saalian (MIS 6) alluvial fan record, is a 4- to 18-m thick alternation of distinct organic (mainly peat and humic clays), siliciclastic alluvial fan (coarse- and medium-grained sands), Rhine (coarse- and medium grained sands), and aeolian (mainly medium-grained sands) stratigraphic units. Organic levels indicate fan stability during the Eemian interglacial (MIS 5e), and Brørup (MIS 5c), Odderade–Ognon interstadial complex (MIS 5a), and Middle Pleniglacial (MIS 3) interstadials 14, 13, 12 and 11 as well as late MIS 2 interstadial 1a. Clastic sediments indicate alluvial fan activity during the Herning (MIS 5d), Rederstall (MIS 5b), Ognon stadial complex (late MIS 5a), Early Pleniglacial (MIS 4) and upper Middle Pleniglacial (upper MIS 3) stadials 13, 12 and 11. Sediments from the coldest and driest period of the Last Glacial (late MIS 3 and MIS 2) are absent and following a phase of aeolian activity, the fan was only reactivated at the MIS 2 to MIS 1 transition (stadial 1). We attribute the absence of fan activity during the coldest period of the last interglacial-glacial cycle to the eastward orientation of the fan making it less sensitive to permafrost melt.The colder MIS substages and stadials in which the Eerbeek fan was active coincided with the presence of permafrost and/or a seasonal, deeply frozen soil, and a relatively humid climate during which vegetation was largely absent. The presence of channels that dissect the underlying organic units suggests that the Eerbeek fan initially responded to the changes from interstadials to stadials by means of erosion. As climate cooled and permafrost/deep frost developed, the fan switched to alluvial aggradation. The consistent presence of coarsening-fining upward sequences suggests a relation with cycles of increased overland flow due to increasingly more frozen subsoil conditions. The fan stratigraphy therefore shows the direct coupling between warmer-colder MIS substages and interstadial-stadial climate cyclicity and alluvial fan response over the entire last interglacial-glacial cycle.

Inorganic phosphors with tunable broadband emission hold significant applications in solid-state lighting. Herein, a series of novel Sr3YGa2O7.5: Bi3+, Eu3+ (abbreviated as SYGO: Bi3+, Eu3+) phosphors with tunable optical properties were synthesized by high-temperature solid-state reaction process. The photoluminescence excitation (PLE) spectrum of Sr3YGa2O7.5: Bi3+ ranges from 200 to 400 nm with two peaks at 280 and 331 nm, matching well with the n-UV chip based white light-emitting diodes (WLED). Under ultraviolet light excitation, a single Bi3+-doped Sr3YGa2O7.5 phosphor exhibited five distinct luminescence peaks at 410, 510, 560, 605, and 700 nm at 10 K, which are attributed to the 3P1→1S0 transition emissions of Bi3+ ions occupying the four Sr sites and one Y site within the Sr3YGa2O7.5 host lattice. The optical tuning of the Sr3YGa2O7.5: Bi3+ phosphor is achieved by designing the Bi3+→Eu3+ energy transfer and changing the excitation wavelength based on the selected site occupation. The Commission Internationale de l'Eclairage (CIE) coordinates and emission color of the Sr3YGa2O7.5: Bi3+, Eu3+ phosphors were successfully tuned from blue via white to red. The energy transfer efficiency from Bi3+ to Eu3+ can reach as high as 89.54 %, and this energy transfer process is predominantly governed by the dipole-quadrupole interaction. In addition, the white LED device prepared by combination of SYGO: 0.02Bi3+, 0.03Eu3+ phosphors with 365 nm chip has high color rendering index (CRI) of 85.5 and low correlated color temperature of 3537 K. As the driving current increases, the white light emitting diodes (WLED) device demonstrates good color stability. Based on these findings, the synthesized SYGO: Bi3+, Eu3+ phosphors can serve as color-tunable and single-phase white phosphors with potential applications in UV-excited white LEDs. © 2025

Integrating environmental, social and governance (ESG) variables into the assessment of a mining project is essential to ensure the short and long term acceptance by the various stakeholders involved and the lack of doing so can put the sustainability of a project at risk. Thus, a holistic approach has been proposed which combines profitability and sustainability analysis with social and environmental considerations for any decisions made on processing operation selection or mine expansion. The potential economic implications of these factors would be used for determining the operational strategy. This study is based on an actual quarry case study and statistical data taken from Spain. Quantitative variables related to ESG aspects have been integrated into a block model, and optimisations were performed based on different plant types and waste disposal strategies. Results demonstrate a strong interdependence between profitability and sustainability. It is observed that strategies related to operating costs impact the environmental and social impacts. A green index is also incorporated to evaluate and compare the different scenarios, determining that the most relevant strategies in adding value to mining projects include investment in new technologies, environmental solutions, and economic and social benefits. Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura Objectius de Desenvolupament Sostenible::8 - Treball Decent i Creixement Econòmic Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables Peer Reviewed