Esteban Asto-Ramos, María Belén Arcentales-Vera, Loreto Troncoso, Faramarz S. Gard, Cristián Huck-Iriart, Diego G. Lamas
Nanocrystalline SrTi 1 − x Fe x O 3 − δ perovskites (x = 0.20–0.50) represent a compositionally tunable platform for cobalt-free symmetric electrodes in intermediate-temperature solid oxide fuel cells. Synthesized via a gel-combustion route, all as-prepared compositions form single-phase cubic perovskites with nanometric domains, while the Fe/Ti ratio governs lattice contraction, mixed Fe + 3 / F e + 4 surface chemistry, and redox responsiveness. Electrochemical impedance spectroscopy reveals that Fe-rich materials (x = 0.35 and x = 0.50) exhibit markedly lower polarization resistances than the x = 0.20 composition under both oxidizing and reducing atmospheres. Distribution of relaxation times analysis reveals that Fe incorporation markedly attenuates the polarization contributions across the intermediate- and high-frequency ranges, confirming accelerated charge-transfer and surface-reaction kinetics under both oxidizing and reducing conditions. Under reducing conditions, STF50 undergoes adaptive structural evolution, including Fe exsolution and the emergence of Ruddlesden–Popper-type domains, highlighting a dynamic interplay between high electrochemical activity and redox-induced restructuring. Preliminary button-cell tests confirm the functional viability of STF50 as a symmetric electrode within the intermediate-temperature range. Overall, nanocrystalline SrTi 1 − x Fe x O 3 − δ emerges as a promising and structurally adaptive electrode family, in which controlled Fe substitution modulates defect chemistry, redox behavior, and electrochemical performance. These findings demonstrate the potential of Fe-rich titanate perovskites as next-generation cobalt-free electrodes for efficient and adaptable IT-SOFC architectures.
Alireza Asgari Motlagh, Timothy McCarthy, Aziz Ahmed
Steel support structures for offshore energy platforms require large volumes of steel and complex manufacturing, making them one of the most expensive elements of any offshore project. Capital expenditure (CAPEX), which includes material procurement, manufacturing, transportation, and installation, typically makes up around 70% of the total lifecycle cost of these structures. Although many studies have proposed cost models to support design and optimization, the approaches used vary considerably in terms of scope, methodology, and level of detail. This paper reviews existing CAPEX cost models for fixed and floating steel offshore structures, covering jackets, monopiles, spar buoys, semi-submersibles, and tension leg platforms, based on peer-reviewed work published mainly between 2000 and 2026. Moreover, this study offers a new quantitative framework that combines cost model completeness, modelling detail, and structural complexity to compare studies. The findings show that material costs appear in 98% of studies, with 66.7% relying on material cost alone. Manufacturing costs have been included in 29% of studies, even though they can account for more than 30% of total production costs in welded steel structures. Transportation and installation costs have received less attention, appearing in 16% and 20% of studies, respectively. Only 14.1% of the reviewed studies include all four CAPEX components together. Finally, the key gaps identified across the reviewed literature are discussed, along with recommendations for future work.
Decentralized hybrid solar photovoltaic systems present a viable option for rural electrification, especially for regions where solar irradiance is high, but grid connectivity is not feasible. In this study, the performance of a 1.6 MW solar photovoltaic–Diesel generator hybrid Mini grid located at Bukuzindu village, Bugala island in Kalangala district, Uganda was assessed. The system’s monthly energy data for the period from July 2019 to June 2023 was collected and analysed. The findings showed that the average monthly electricity generated by the plant was 203.1 MWh, of which 174.1 MWh, 22.4 MWh, 0.96 MWh, and 5.4 MWh, respectively, were distributed to consumers, accounted for generation and transmission losses, consumed at the plant site, and used to charge the battery bank system. The solar PV performance ratio and capacity factor were found to be 65.6% and 13.4%, respectively. Meanwhile, the mini grid capacity factor and overall combined generation and transmission loss were 17.39% and 11.03%, respectively.
Public institutions, as key entities fulfilling public service functions, are characterized by their substantial scale, high energy intensity, and significant demonstration role in society. Improving their energy efficiency is therefore pivotal for achieving national decarbonization targets. This study addresses the gaps in current energy efficiency evaluation systems and the lack of coordination among stakeholders by proposing a novel framework combining CRITIC-based weighting with a tripartite evolutionary game model. The evaluation system encompasses four dimensions: energy consumption, technological innovation, operational management, and contextual factors. The CRITIC method is applied to determine indicator weights, and a tripartite evolutionary game model involving the government, integrated energy service providers (IESPs), and public institutions is constructed to explore strategy evolution and equilibrium under a Carbon Inclusion mechanism. A case study of a university in Fujian Province is used to assess seven retrofit options. Results show that technological innovation indicators hold the highest weight (0.258), highlighting the importance of low-carbon technologies. The comprehensive retrofit plan yields the best results, reducing net present cost by 18.4%, annual carbon emissions by 25.2%, and electricity consumption by 34.4%. The game analysis reveals that government subsidies accelerate strategy evolution in the early stages but can be phased out over time. IESPs should implement dynamic carbon pricing and adaptive incentives. Overall, this study provides a systematic theoretical framework and practical path for improving energy efficiency in public institutions.
Electricity-price dynamics in energy-transitioning power systems reflect the interaction of fuel costs, carbon prices, financial conditions, regulatory information, and market expectations. This study examines whether text-derived news indicators provide incremental predictive information for Polish electricity prices. A curated English-language European policy-news corpus identified through a GDELT-assisted collection procedure is processed using two separate natural-language-processing branches. TF–IDF is used to characterize the thematic prominence of selected energy and climate-policy terms, while VADER is applied directly to article text to derive an interpretable news-tone indicator, referred to as the Climate Change News Index. These indicators are aligned with electricity, natural-gas, coal, oil, carbon-allowance, and equity-market variables. Ordinary Least Squares and Elastic Net models are evaluated using chronological out-of-sample forecasts. Market fundamentals remain the main predictive inputs, while the contribution of text-derived variables is small and specification-dependent. The results therefore indicate limited incremental predictive information rather than systematic forecasting superiority. The study is observational, and the reported relationships are interpreted as associative and predictive rather than causal. The proposed workflow provides a transparent way to incorporate policy-news information into electricity-price analysis. However, it does not replace physical power-system variables but it provides additional predictive power for better forecasting which can be useful for the market players.
