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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.

Thermal energy storage (TES) plays a key role in concentrating solar power (CSP) plants by enhancing dispatchability and improving overall system efficiency. This study presents a comparative techno-economic analysis of three TES configurations integrated into CSP plants: (i) the conventional two-tank molten salt system, (ii) a phase change material (PCM)-based system with a cascade arrangement, and (iii) a concrete-based system. While technical performance simulations indicate similar annual energy production across all cases, significant differences emerge in economic viability. The PCM TES system demonstrates the lowest levelized cost of electricity (LCoE) at $14.35/kWh, leveraging its high energy density and reduced material requirements, despite lower efficiency (93 % compared to 99 % in molten salt). Conversely, the concrete TES system, while capable of extended discharge at partial loads, incurs higher parasitic losses and investment costs, resulting in a higher LCoE ($16.16/kWh). The cost analysis further highlights the cost-performance quotient (CPQ) as a valuable metric for assessing TES competitiveness, with PCM exhibiting the most favorable CPQ of $1.04/kWh. These findings underscore the necessity of integrating economic assessments into TES selection for CSP plants. Moreover, the study identifies opportunities for cost reduction in concrete TES through optimized modular designs and improved material formulations. This work provides valuable insights for policymakers, engineers, and industry stakeholders aiming to enhance the financial feasibility of next-generation CSP storage solutions. This study receives funding from the Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033) through the PCI2020-120695-2 project and the European Union “NextGenerationEU”/PRTR“. CSP-ERA.NET is supported by the European Commission within the EU Framework Programme for Research and Innovation Horizon 2020 (Cofund ERA-NET Action, N° 838311). This work was partially funded by the Ministerio de Ciencia e Innovación de España TED2021-132216A-I00 funded by MCIN/AEI/10.13039/501100011033 and the European Union by NextGenerationEU/PRTR. This work was partially funded by the Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación (AEI) (PID2021-123511OB-C31 – MCIN/AEI/10.13039/501100011033/FEDER, UE) and (RED2022-134219-T). This work is partially supported by ICREA under the ICREA Academia programme. The authors from University of Lleida would like to thank the Departament de Recerca i Universitats of the Catalan Government for the quality accreditation given to their research group (2021 SGR 01615). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia.

ABSTRACTMedia coverage is a key factor in increasing the flow and accessibility of information among the firm's stakeholders. Drawing on the socioemotional wealth (SEW) perspective, we investigate the antecedents of the level of media coverage of family firms' activism in sustainability. Using hand‐collected data from a sample of public Italian family firms, we provide several novel contributions to the academic debate. First, we find that family involvement on the board of directors is negatively associated with the level of media coverage of the family firm's engagement in sustainability. Conversely, we find that later generational stages of the family business are positively associated with the level of corporate media coverage on sustainability. Our study advances the literature on both corporate sustainability issues and media coverage in the context of family businesses.

This study aims to review the literature on environmental disclosure and firm performance in order to show current trends, challenges, and adventures for future research. We attempted a systematic and structured literature review of 67 studies published in 2001-2023 using the accounting journal in the Chartered Accounting Business School (CABS) ranking. The analysis revealed three main research streams: 1) firm performance, CSR and sustainability; 2) accounting and environmental disclosure; 3) board of directors and decision-making process in the field environment and firm performance. The relevance of this literature review is due to understanding the state of the art between environmental disclosure and firm performance. Through our work, we highlight the current and future issues in the firm performance and environmental disclosure. This paper supports future research and it is directed to academics, practitioners, policy makers and decision makers.

Understanding the causes of past atmospheric methane (CH4) variability is important for characterizing the relationship between CH4, global climate and terrestrial biogeochemical cycling. Ice core records of atmospheric CH4 contain rapid variations linked to abrupt climate changes of the last glacial period known as Dansgaard-Oeschger (DO) events and Heinrich events (HE)1,2. The drivers of these CH4 variations remain unknown but can be constrained with ice core measurements of the stable isotopic composition of atmospheric CH4, which is sensitive to the strength of different isotopically distinguishable emission categories (microbial, pyrogenic and geologic)3-5. Here we present multi-decadal-scale measurements of δ13C-CH4 and δD-CH4 from the WAIS Divide and Talos Dome ice cores and identify abrupt 1‰ enrichments in δ13C-CH4 synchronous with HE CH4 pulses and 0.5‰ δ13C-CH4 enrichments synchronous with DO CH4 increases. δD-CH4 varied little across the abrupt CH4 changes. Using box models to interpret these isotopic shifts6 and assuming a constant δ13C-CH4 of microbial emissions, we propose that abrupt shifts in tropical rainfall associated with HEs and DO events enhanced 13C-enriched pyrogenic CH4 emissions, and by extension global wildfire extent, by 90-150%. Carbon cycle box modelling experiments7 suggest that the resulting released terrestrial carbon could have caused from one-third to all of the abrupt CO2 increases associated with HEs. These findings suggest that fire regimes and the terrestrial carbon cycle varied contemporaneously and substantially with past abrupt climate changes of the last glacial period.

In floating photovoltaics (FPV), modules are installed on bodies of water to alleviate the land competition arising from the growing deployment of photovoltaics (PV). However, the installation of artificial structures on water basins can affect the landscape and raise concerns even among those in favor of renewables. This work specifically investigates the public acceptance of FPV among renewable energy supporters to identify its main drivers and barriers. The investigation was conducted through a public survey, which counted more than 300 respondents favorable to renewable energies. The findings reveal that, while public acceptance of FPV remains positive, it is lower than that experienced by renewable energy systems in general. This disparity is mainly due to concerns surrounding the landscape and fauna impacts of this novel technology. In particular, an inverse relationship between FPV acceptance and its perceived alteration of the landscape beauty is found. Notably, respondents expressing a negative opinion on FPV are also those most concerned by the landscape impact of traditional PV. The investigation also proposes some preliminary solutions for enhancing FPV's social acceptance. The effectiveness of these potential measures is evaluated, providing valuable insights for stakeholders and policymakers in the renewable energy sector.

Not only advances but also old addictions, setbacks, obstructions and delays are observed during COP16 (on biodiversity), COP29 (on climate change) and G20 in a year full of tragedies resulting from climate change; we need to look in the rearview mirror and plan new paths to be presented and discussed at COP30, in 2025, in the Brazilian Amazon. Worldwide temperature records show that 2023 and 2024 were the warmest in at least the last 2000 years (Esper, Torbenson, and Büntgen 2024). About 90% of the excess heat trapped by greenhouse gases and 30% of human emissions of carbon dioxide are stored in the ocean, shielding the planet from even more rapid changes in the biosphere. The recent acceleration in climate change is a threat not only to terrestrial systems but also to largely neglected marine ecosystems and their socio-biodiversity. Considering the relationship between global warming and biological extinctions (Malanoski et al. 2024), as well as the high vulnerability of marine biodiversity to these global threats (Pinsky et al. 2019), we call for the urgent need to create global and multilateral policies that are based on climate-smart ocean planning and carbon neutrality, focused on climate adaptation and mitigation strategies to protect, restore and foster sustainable management of marine socio-ecological systems (Frazão Santos et al. 2024).