Pub Date : 2026-03-01Epub Date: 2026-01-09DOI: 10.1016/j.nexus.2026.100630
Montserrat Montalà-Palau , Marc Cheah Mañé , Oriol Gomis-Bellmunt
The concept of resilience has gained prominence across diverse fields and has recently emerged as a crucial concept in power systems, complementing traditional notions of reliability, robustness, and security. Despite this, standardized approaches to integrating resilience into power system planning remain limited. This study proposes a novel framework that combines Geographic Information Systems (GIS) with AC and DC Optimal Power Flow (OPF) analysis to quantify power system resilience. A new resilience index is introduced, accounting for external hazards, system vulnerabilities, and inherent strengths. Recognizing resilience as a multi-layered challenge that requires comprehensive data management, the methodology utilizes GIS to efficiently integrate both qualitative and quantitative spatial and system data, enabling robust analysis even in data-sparse or heterogeneous environments. The methodology is implemented as an open-source tool and applied to a rural power network in Spain, illustrating how different mitigation strategies affect resilience outcomes. In the demonstrated case study, the proposed mitigation strategies reduced the system’s overall power at risk by nearly 90%. The tool constitutes a valuable resource for resilience-oriented power system planning and is freely available at [1].
{"title":"How resilient is a power system? An open-source tool integrating GIS and Optimal Power Flow for resilience assessment","authors":"Montserrat Montalà-Palau , Marc Cheah Mañé , Oriol Gomis-Bellmunt","doi":"10.1016/j.nexus.2026.100630","DOIUrl":"10.1016/j.nexus.2026.100630","url":null,"abstract":"<div><div>The concept of resilience has gained prominence across diverse fields and has recently emerged as a crucial concept in power systems, complementing traditional notions of reliability, robustness, and security. Despite this, standardized approaches to integrating resilience into power system planning remain limited. This study proposes a novel framework that combines Geographic Information Systems (GIS) with AC and DC Optimal Power Flow (OPF) analysis to quantify power system resilience. A new resilience index is introduced, accounting for external hazards, system vulnerabilities, and inherent strengths. Recognizing resilience as a multi-layered challenge that requires comprehensive data management, the methodology utilizes GIS to efficiently integrate both qualitative and quantitative spatial and system data, enabling robust analysis even in data-sparse or heterogeneous environments. The methodology is implemented as an open-source tool and applied to a rural power network in Spain, illustrating how different mitigation strategies affect resilience outcomes. In the demonstrated case study, the proposed mitigation strategies reduced the system’s overall power at risk by nearly 90%. The tool constitutes a valuable resource for resilience-oriented power system planning and is freely available at [1].</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100630"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146037985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-01Epub Date: 2026-02-09DOI: 10.1016/j.nexus.2026.100664
Xinyi Liu , Quan Lai , Shan Yin , Rihe Gao
Water use efficiency (WUE) encompasses precipitation use efficiency (PUE), soil water use efficiency (SWUE), and groundwater use efficiency (GWUE) and serves as a key indicator for evaluating ecosystem responses to drought, particularly as climate change continues to intensify. This study investigates the responses of various WUE indicators to drought conditions on the Mongolian Plateau at a spatial resolution of 0.1° from 2000 to 2020. Drought conditions are measured using drought indices such as the Standardized Precipitation Evapotranspiration Index (SPEI), Soil Moisture Anomaly Index (SMAI), and Groundwater Storage Deficit Index (GWSDI). The findings reveal that while PUE, SWUE, and GWUE generally exhibited upward trends, their responses to drought varied significantly. In arid regions, WUE indicators showed positive correlations with drought indices, while in humid regions, negative correlations were observed. The SPEI and SMAI predominantly indicated a wetting trend, whereas GWSDI reflected a drying trend across most of the study area (67.47 %). Moreover, the study identified lagged effects of drought on PUE, SWUE and GWUE that ranged from 2.4 to 4.4 months and varied according to vegetation type and climatic region. Although drought typically led to reductions in PUE and SWUE, enhancements of GWUE were observed in both semi-humid forests and semi-arid sandy lands under groundwater drought. Given the Mongolian Plateau's ecological fragility and its critical role in East Asia's water and carbon cycles, these findings underscore the complexity of drought impacts on WUE and highlight the need to develop appropriate ecosystem management strategies to address the challenges posed by climate change.
{"title":"Assessing the impact of drought on water use efficiency among ecosystems on the Mongolian Plateau","authors":"Xinyi Liu , Quan Lai , Shan Yin , Rihe Gao","doi":"10.1016/j.nexus.2026.100664","DOIUrl":"10.1016/j.nexus.2026.100664","url":null,"abstract":"<div><div>Water use efficiency (WUE) encompasses precipitation use efficiency (PUE), soil water use efficiency (SWUE), and groundwater use efficiency (GWUE) and serves as a key indicator for evaluating ecosystem responses to drought, particularly as climate change continues to intensify. This study investigates the responses of various WUE indicators to drought conditions on the Mongolian Plateau at a spatial resolution of 0.1° from 2000 to 2020. Drought conditions are measured using drought indices such as the Standardized Precipitation Evapotranspiration Index (SPEI), Soil Moisture Anomaly Index (SMAI), and Groundwater Storage Deficit Index (GWSDI). The findings reveal that while PUE, SWUE, and GWUE generally exhibited upward trends, their responses to drought varied significantly. In arid regions, WUE indicators showed positive correlations with drought indices, while in humid regions, negative correlations were observed. The SPEI and SMAI predominantly indicated a wetting trend, whereas GWSDI reflected a drying trend across most of the study area (67.47 %). Moreover, the study identified lagged effects of drought on PUE, SWUE and GWUE that ranged from 2.4 to 4.4 months and varied according to vegetation type and climatic region. Although drought typically led to reductions in PUE and SWUE, enhancements of GWUE were observed in both semi-humid forests and semi-arid sandy lands under groundwater drought. Given the Mongolian Plateau's ecological fragility and its critical role in East Asia's water and carbon cycles, these findings underscore the complexity of drought impacts on WUE and highlight the need to develop appropriate ecosystem management strategies to address the challenges posed by climate change.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100664"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146188346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study analyzes and forecasts economic, environmental, and health indicators in West Asian and East Asian countries. The innovation of this study is the combination of health parameters related to respiratory diseases (cancer) with economic parameters and air pollution, and the use of artificial intelligence models for long-term forecasting of these indicators. The main objective of this study was to develop and compare four AI-based models for forecasting GDP, CO2 emissions, and TBL cancer in selected countries from West and East Asia until 2040. After comparing the models using error measures such as RMSE, MAE, and MAPE, the ARIMA model was selected as the best model. The results of the forecast for one of the West Asian countries until 2040 show that the ARIMA model with RMSE errors of 0.1236 in CO2 emissions, 747.26 in GDP, and 1140.81 in TBL cancer was selected as the best model. The forecast results show that East Asian countries, especially China, have had significant growth in all indicators, especially in CO2 emissions and GDP, so that in CO2 emissions, the growth in East Asia has reached 245.5 %, while this value in West Asia has been 96.65 %. Also, the growth of TBL cancer and GDP in East Asian countries has been faster than that in West Asia. China has experienced significant growth in all three indicators. This study can help researchers and decision-makers adopt better policies in the fields of public health and sustainable development by increasing awareness of future trends.
{"title":"Comparison of classical statistical models for forecasting CO₂ emissions, GDP, and TBL cancer indicators: A comparative analysis of East and West Asia","authors":"Seyed Mohieddin Moezzi , Mohammadali Allahrabbi Shirazi , Alireza Rajabi Zadeh Monfared , Hossein Yousefi","doi":"10.1016/j.nexus.2026.100682","DOIUrl":"10.1016/j.nexus.2026.100682","url":null,"abstract":"<div><div>This study analyzes and forecasts economic, environmental, and health indicators in West Asian and East Asian countries. The innovation of this study is the combination of health parameters related to respiratory diseases (cancer) with economic parameters and air pollution, and the use of artificial intelligence models for long-term forecasting of these indicators. The main objective of this study was to develop and compare four AI-based models for forecasting GDP, CO<sub>2</sub> emissions, and TBL cancer in selected countries from West and East Asia until 2040. After comparing the models using error measures such as RMSE, MAE, and MAPE, the ARIMA model was selected as the best model. The results of the forecast for one of the West Asian countries until 2040 show that the ARIMA model with RMSE errors of 0.1236 in CO<sub>2</sub> emissions, 747.26 in GDP, and 1140.81 in TBL cancer was selected as the best model. The forecast results show that East Asian countries, especially China, have had significant growth in all indicators, especially in CO<sub>2</sub> emissions and GDP, so that in CO<sub>2</sub> emissions, the growth in East Asia has reached 245.5 %, while this value in West Asia has been 96.65 %. Also, the growth of TBL cancer and GDP in East Asian countries has been faster than that in West Asia. China has experienced significant growth in all three indicators. This study can help researchers and decision-makers adopt better policies in the fields of public health and sustainable development by increasing awareness of future trends.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100682"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146188434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Microalgae efficiently sequester carbon and accumulate neutral lipids; however, challenges persist in achieving high triacylglycerol (TAG) and biofuel yields. This study presents a novel two-stage salt stress strategy that enhances neutral lipid accumulation, jet fuel production, and biodiesel quality in Scenedesmus sp. To address this, Scenedesmus sp. was cultivated under varying NaCl concentrations (0–0.4 M) and time intervals (0–12 days) using a two-stage process. In stage I, control cells (0 M NaCl) showed a higher CO₂ fixation rate (122.06 mg L⁻¹ d⁻¹), while 0.4 M NaCl-treated cells recorded the highest neutral lipid content (77.01 %). In stage II under 0.4 M NaCl at 8 days, 1.48 kg biomass yielded 1 kg microalgal oil, and 2.59 kg biomass produced 1 kg jet fuel. Further, second derivative spectra from FTIR spectroscopy revealed shifts in functional groups favoring neutral lipid synthesis (peaks at 2923 cm⁻¹ and 1746 cm⁻¹), while thermogravimetric analysis (TGA) showed decomposition of lipids and carbohydrates during pyrolysis. Additionally, CHNS analysis revealed maximum higher heating value (25.64 MJ/kg), and lower heating values (24.71 MJ/kg) in 8th-day biomass. GC-MS analysis revealed a predominance of saturated fatty acids (SFAs; 66.67 %), particularly C16–C18, over monounsaturated fatty acids (MUFAs; 18 %) and polyunsaturated fatty acids (PUFAs; 16 %). Notably, biodiesel produced from 8th day biomass met both the EN 14214 and ASTM D6751 standards, demonstrating the potential of Scenedesmus sp. for biodiesel feedstock. Importantly, biodiesel produced from the 8th-day biomass met both the EN 14214 and ASTM D6751 standards. Thus, current study highlights the potential of salt supplementation in Scenedesmus sp. BHU1 to enhance triacylglycerol, supporting its use as a biodiesel feedstock.
微藻能有效地固碳和积累中性脂;然而,在实现高三酰甘油(TAG)和生物燃料产量方面仍然存在挑战。本研究提出了一种新的两阶段盐胁迫策略,可以提高Scenedesmus sp的中性脂质积累、喷气燃料生产和生物柴油质量。为了解决这个问题,采用两阶段工艺在不同的NaCl浓度(0-0.4 M)和时间间隔(0-12天)下培养Scenedesmus sp。在第一阶段,对照细胞(0 M NaCl)显示出更高的CO₂固定率(122.06 mg L -毒血症),而0.4 M NaCl处理细胞的中性脂质含量最高(77.01%)。在第II阶段,在0.4 M NaCl条件下8天,1.48 kg生物质产生1 kg微藻油,2.59 kg生物质产生1 kg喷气燃料。此外,FTIR光谱的二阶导数光谱显示,官能团的变化有利于中性脂质合成(峰值在2923 cm⁻¹和1746 cm⁻¹处),而热重分析(TGA)显示了热解过程中脂质和碳水化合物的分解。CHNS分析显示,第8天生物量的最高热值为25.64 MJ/kg,最低热值为24.71 MJ/kg。GC-MS分析显示饱和脂肪酸(sfa, 66.67%),特别是C16-C18,高于单不饱和脂肪酸(MUFAs, 18%)和多不饱和脂肪酸(PUFAs, 16%)。值得注意的是,从第8天的生物质中生产的生物柴油符合EN 14214和ASTM D6751标准,这表明了Scenedesmus sp.作为生物柴油原料的潜力。重要的是,从第8天的生物质中生产的生物柴油符合EN 14214和ASTM D6751标准。因此,目前的研究强调了在Scenedesmus sp. BHU1中添加盐以增强三酰甘油的潜力,支持其作为生物柴油原料的使用。
{"title":"Salt-regulated triacylglycerol accumulation and biodiesel quality of Scenedesmus sp. BHU1 under two-stage cultivation","authors":"Rahul Prasad Singh , Priya Yadav , Ajay Kumar , Amit Kaushik , Aditi Arya , Mahaswetta Saikia , Rajan Kumar Gupta , Laurent Dufossé","doi":"10.1016/j.nexus.2026.100655","DOIUrl":"10.1016/j.nexus.2026.100655","url":null,"abstract":"<div><div>Microalgae efficiently sequester carbon and accumulate neutral lipids; however, challenges persist in achieving high triacylglycerol (TAG) and biofuel yields. This study presents a novel two-stage salt stress strategy that enhances neutral lipid accumulation, jet fuel production, and biodiesel quality in <em>Scenedesmus</em> sp. To address this, <em>Scenedesmus</em> sp. was cultivated under varying NaCl concentrations (0–0.4 M) and time intervals (0–12 days) using a two-stage process. In stage I, control cells (0 M NaCl) showed a higher CO₂ fixation rate (122.06 mg L⁻¹ d⁻¹), while 0.4 M NaCl-treated cells recorded the highest neutral lipid content (77.01 %). In stage II under 0.4 M NaCl at 8 days, 1.48 kg biomass yielded 1 kg microalgal oil, and 2.59 kg biomass produced 1 kg jet fuel. Further, second derivative spectra from FTIR spectroscopy revealed shifts in functional groups favoring neutral lipid synthesis (peaks at 2923 cm⁻¹ and 1746 cm⁻¹), while thermogravimetric analysis (TGA) showed decomposition of lipids and carbohydrates during pyrolysis. Additionally, CHNS analysis revealed maximum higher heating value (25.64 MJ/kg), and lower heating values (24.71 MJ/kg) in 8<sup>th</sup>-day biomass. GC-MS analysis revealed a predominance of saturated fatty acids (SFAs; 66.67 %), particularly C16–C18, over monounsaturated fatty acids (MUFAs; 18 %) and polyunsaturated fatty acids (PUFAs; 16 %). Notably, biodiesel produced from 8<sup>th</sup> day biomass met both the EN 14214 and ASTM <span><span>D6751</span><svg><path></path></svg></span> standards, demonstrating the potential of <em>Scenedesmus</em> sp. for biodiesel feedstock. Importantly, biodiesel produced from the 8<sup>th</sup>-day biomass met both the EN 14214 and ASTM <span><span>D6751</span><svg><path></path></svg></span> standards. Thus, current study highlights the potential of salt supplementation in <em>Scenedesmus</em> sp. BHU1 to enhance triacylglycerol, supporting its use as a biodiesel feedstock.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100655"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146188355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-01Epub Date: 2026-02-09DOI: 10.1016/j.nexus.2026.100679
Chima Tansi Uwaezuoke, Nnamdi I. Nwulu
This paper presents a complete overview of optimal power dispatch algorithms and reliability analysis methods for hybrid energy systems incorporating combined heat and power (CHP), photovoltaic (PV), wind energy and grid connections in agriculture applications. Agriculture presents particular energy issues due to seasonal needs, isolated locations, and varying power requirements. Hybrid systems provide intriguing solutions by combining complementary energy sources, but require advanced techniques for power dispatch and reliability enhancement.
This review was carried out using a systematic methodology, with a structured search across the Web of Science Core Collection, Scopus, IEEE Xplore Digital Library, and ScienceDirect databases. The search terms were ‘hybrid renewable energy,” “CHP integration,” or ‘reliability analysis’. Studies were included if they focused on hybrid renewable energy systems involving CHP, photovoltaic, wind or grid integration, addressed optimisation, dispatch, or reliability analysis, and were published between 2015 and 2025 in peer-reviewed journals or conference proceedings. The exclusion criteria excluded simply theoretical works without validation, research not related to agricultural uses, and articles that lacked quantitative assessment. In total, 45 relevant studies were synthesised.
Multi-objective optimisation frameworks, advanced reliability evaluation methodologies, technology advances in energy storage and system integration, and economic-environmental sustainability concerns are all critical areas of study. Research gaps are identified, such as a lack of integration of CHP with renewable energy in agricultural contexts, insufficient dependability measurement for critical agricultural activities, and inadequate frameworks for comprehensively resolving economic-environmental-reliability trade-offs. Future research directions will focus on standardised but adaptable system designs, improved integration of thermal and electrical needs, and complete modelling approaches that consider social and regulatory factors. This synthesis contributes to the development of more efficient, reliable, and sustainable agricultural energy solutions.
本文介绍了在农业应用中结合热电联产(CHP)、光伏(PV)、风能和电网连接的混合能源系统的最佳电力调度算法和可靠性分析方法的完整概述。由于季节性需求、孤立的地点和不同的电力需求,农业提出了特殊的能源问题。混合动力系统通过结合互补能源提供了有趣的解决方案,但需要先进的电力调度和可靠性增强技术。本综述采用系统方法,在Web of Science核心馆藏、Scopus、IEEE Xplore数字图书馆和ScienceDirect数据库中进行结构化搜索。搜索词是“混合可再生能源”、“热电联产整合”或“可靠性分析”。如果研究的重点是涉及热电联产、光伏、风能或电网集成的混合可再生能源系统,涉及优化、调度或可靠性分析,并在2015年至2025年之间发表在同行评审期刊或会议论文集上,则纳入研究。排除标准仅排除未经验证的理论作品、与农业用途无关的研究和缺乏定量评估的文章。总共综合了45项相关研究。多目标优化框架、先进的可靠性评估方法、储能和系统集成方面的技术进步以及经济-环境可持续性问题都是研究的关键领域。指出了研究上的差距,例如在农业背景下缺乏热电联产与可再生能源的整合,对关键农业活动的可靠性测量不足,以及全面解决经济-环境-可靠性权衡的框架不足。未来的研究方向将集中在标准化但适应性强的系统设计,改进热电需求的集成,以及考虑社会和监管因素的完整建模方法。这种综合有助于开发更高效、可靠和可持续的农业能源解决方案。
{"title":"Hybrid renewable energy for agriculture: Review of optimising power dispatch and reliability analysis","authors":"Chima Tansi Uwaezuoke, Nnamdi I. Nwulu","doi":"10.1016/j.nexus.2026.100679","DOIUrl":"10.1016/j.nexus.2026.100679","url":null,"abstract":"<div><div>This paper presents a complete overview of optimal power dispatch algorithms and reliability analysis methods for hybrid energy systems incorporating combined heat and power (CHP), photovoltaic (PV), wind energy and grid connections in agriculture applications. Agriculture presents particular energy issues due to seasonal needs, isolated locations, and varying power requirements. Hybrid systems provide intriguing solutions by combining complementary energy sources, but require advanced techniques for power dispatch and reliability enhancement.</div><div>This review was carried out using a systematic methodology, with a structured search across the Web of Science Core Collection, Scopus, IEEE Xplore Digital Library, and ScienceDirect databases. The search terms were ‘hybrid renewable energy,” “CHP integration,” or ‘reliability analysis’. Studies were included if they focused on hybrid renewable energy systems involving CHP, photovoltaic, wind or grid integration, addressed optimisation, dispatch, or reliability analysis, and were published between 2015 and 2025 in peer-reviewed journals or conference proceedings. The exclusion criteria excluded simply theoretical works without validation, research not related to agricultural uses, and articles that lacked quantitative assessment. In total, 45 relevant studies were synthesised.</div><div>Multi-objective optimisation frameworks, advanced reliability evaluation methodologies, technology advances in energy storage and system integration, and economic-environmental sustainability concerns are all critical areas of study. Research gaps are identified, such as a lack of integration of CHP with renewable energy in agricultural contexts, insufficient dependability measurement for critical agricultural activities, and inadequate frameworks for comprehensively resolving economic-environmental-reliability trade-offs. Future research directions will focus on standardised but adaptable system designs, improved integration of thermal and electrical needs, and complete modelling approaches that consider social and regulatory factors. This synthesis contributes to the development of more efficient, reliable, and sustainable agricultural energy solutions.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100679"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146188447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-01Epub Date: 2026-01-10DOI: 10.1016/j.nexus.2026.100638
Zhou Yunlong , Sun Meng
Solar photocatalytic hydrogen production is an important technology for green hydrogen energy production. However, due to the limitation of the light absorption band of photocatalysts, the most commonly used catalysts are difficult to achieve efficient and stable photocatalysis under sunlight. Herein, a carbon microsphere-WO3 composite photocatalytic material was prepared by hydrothermal synthesis, which accelerated the directional transfer of photogenerated electrons. There is a strong local electric field effect in the carbon microsphere-WO3 composite photocatalytic material, promoting the directional transfer of electrons. Photogenerated carriers rapidly migrate from WO3 to the active sites on the surface of carbon microspheres, improving the kinetics of the photocatalytic H+ reduction reaction and accelerating the efficiency of solar photocatalytic hydrogen production. When the doping concentration of carbon microspheres is 30%, the photocatalytic hydrogen production rate of the composite material reaches 520 μmol·h-1·g-1, which is 32.5 times that of pure WO3. The carbon microsphere-WO3 composite photocatalytic material has superior photo-stability and recyclability. The experimental results reveal the reaction mechanism of the efficient catalysis of the composite material. This study opens up new prospects for the practical application of photocatalysts.
{"title":"Study on the local electric field effect of electron transfer in straw-derived carbon microsphere-WO3 composite materials: Photocatalytic hydrogen production performance and mechanism under solar light","authors":"Zhou Yunlong , Sun Meng","doi":"10.1016/j.nexus.2026.100638","DOIUrl":"10.1016/j.nexus.2026.100638","url":null,"abstract":"<div><div>Solar photocatalytic hydrogen production is an important technology for green hydrogen energy production. However, due to the limitation of the light absorption band of photocatalysts, the most commonly used catalysts are difficult to achieve efficient and stable photocatalysis under sunlight. Herein, a carbon microsphere-WO<sub>3</sub> composite photocatalytic material was prepared by hydrothermal synthesis, which accelerated the directional transfer of photogenerated electrons. There is a strong local electric field effect in the carbon microsphere-WO<sub>3</sub> composite photocatalytic material, promoting the directional transfer of electrons. Photogenerated carriers rapidly migrate from WO<sub>3</sub> to the active sites on the surface of carbon microspheres, improving the kinetics of the photocatalytic H<sup>+</sup> reduction reaction and accelerating the efficiency of solar photocatalytic hydrogen production. When the doping concentration of carbon microspheres is 30%, the photocatalytic hydrogen production rate of the composite material reaches 520 μmol·h<sup>-1</sup>·g<sup>-1</sup>, which is 32.5 times that of pure WO<sub>3</sub>. The carbon microsphere-WO<sub>3</sub> composite photocatalytic material has superior photo-stability and recyclability. The experimental results reveal the reaction mechanism of the efficient catalysis of the composite material. This study opens up new prospects for the practical application of photocatalysts.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100638"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-01Epub Date: 2026-01-10DOI: 10.1016/j.nexus.2026.100640
Safa Slouma , Abdessami Soyed
This study deals with a first approach to exploit the Nexus Approach applied to PV-powered irrigation in North Africa—a region with high solar potential but water scarcity, such as Tunisia. Tunisia had faced an arid and very changeable climate, including significant decreases in annual rainfall (455 mm per year). This research focuses on a techno-economic, social and environmental assessment of a standalone solar-powered irrigation system (SPVWPS) in the Tunisian area, based on the Water-Energy-Food (WEF) Nexus approach. It proposes a holistic assessment framework that synthesizes these interconnected dimensions. The study assesses the system's optimal sizing, economic feasibility, and social and environmental benefits by employing an optimization framework that combines solar energy potential, crop water requirements, and cost-effectiveness. Via PVsyst software, the system's performance is simulated under varying climatic conditions, with sensitivity analyses conducted to evaluate the component costs’ impact, solar irradiance variations, and water demand shapes. Economic indicators such as Net Present Value are analyzed, while environmental benefits are quantified in terms of CO₂ emissions reduction compared to conventional diesel-powered systems. Results demonstrate that the proposed SPVWPS is economically feasible and significant reductions in greenhouse gas emissions avoid >3348.57 kg of CO2 per year. The nexus approach further highlights the system's potential to enhance water-use efficiency with an average exceeding 20 m³ per day and crop productivity. This average can irrigate up to 1.5 hectares of olive crops. Policy recommendations are provided to facilitate large-scale adoption, emphasizing the role of subsidies and technical training. This study contributes to offering a replicable model for similar arid regions in North Africa.
{"title":"Optimal techno-economic and environmental assessment of a standalone solar-powered irrigation system in North Africa based on the nexus approach","authors":"Safa Slouma , Abdessami Soyed","doi":"10.1016/j.nexus.2026.100640","DOIUrl":"10.1016/j.nexus.2026.100640","url":null,"abstract":"<div><div>This study deals with a first approach to exploit the Nexus Approach applied to PV-powered irrigation in North Africa—a region with high solar potential but water scarcity, such as Tunisia. Tunisia had faced an arid and very changeable climate, including significant decreases in annual rainfall (455 mm per year). This research focuses on a techno-economic, social and environmental assessment of a standalone solar-powered irrigation system (SPVWPS) in the Tunisian area, based on the Water-Energy-Food (WEF) Nexus approach. It proposes a holistic assessment framework that synthesizes these interconnected dimensions. The study assesses the system's optimal sizing, economic feasibility, and social and environmental benefits by employing an optimization framework that combines solar energy potential, crop water requirements, and cost-effectiveness. Via PVsyst software, the system's performance is simulated under varying climatic conditions, with sensitivity analyses conducted to evaluate the component costs’ impact, solar irradiance variations, and water demand shapes. Economic indicators such as Net Present Value are analyzed, while environmental benefits are quantified in terms of CO₂ emissions reduction compared to conventional diesel-powered systems. Results demonstrate that the proposed SPVWPS is economically feasible and significant reductions in greenhouse gas emissions avoid >3348.57 kg of CO<sub>2</sub> per year. The nexus approach further highlights the system's potential to enhance water-use efficiency with an average exceeding 20 m³ per day and crop productivity. This average can irrigate up to 1.5 hectares of olive crops. Policy recommendations are provided to facilitate large-scale adoption, emphasizing the role of subsidies and technical training. This study contributes to offering a replicable model for similar arid regions in North Africa.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100640"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-01Epub Date: 2026-02-10DOI: 10.1016/j.nexus.2026.100678
Zhiquan Yao, Zhengkai Tu
Proton exchange membrane fuel cells (PEMFCs) represent a key technology for hydrogen energy utilization, yet their reliance on high-purity hydrogen restricts further advancement. While hydrogen-rich reforming gas can reduce costs, the CO present in such gas poisons the catalyst. A novel treatment method involves creating a mild hydrogen-deficient environment to enable rapid recovery from high-CO poisoning states. This approach utilizes dual-cell cycling to maintain stable operation in CO-containing environments, though research on this method remains limited. This study quantitatively analyzed the effects of CO concentration, back pressure, humidity, and temperature through multifactor experiments. A 100-h endurance test under periodic purging conditions revealed fundamentally different degradation pathways: CO exposure caused irreversible damage—a 14.29% loss in electrochemically active surface area, a 34.4% increase in charge transfer resistance, severe catalyst agglomeration, platinum particle growth reaching 55.6%, and oxidation significantly concentrated at the anode inlet due to CO concentration gradients. In contrast, hydrogen operation induced only minor degradation primarily attributable to cathode flooding. This study identified the dual effects of operating parameters, elucidated two distinct failure mechanisms, and provided critical insights for developing mitigation strategies, enabling PEMFC to operate continuously using impure hydrogen fuel.
{"title":"Study on degradation mechanisms of proton exchange membrane fuel cell under CO poisoning","authors":"Zhiquan Yao, Zhengkai Tu","doi":"10.1016/j.nexus.2026.100678","DOIUrl":"10.1016/j.nexus.2026.100678","url":null,"abstract":"<div><div>Proton exchange membrane fuel cells (PEMFCs) represent a key technology for hydrogen energy utilization, yet their reliance on high-purity hydrogen restricts further advancement. While hydrogen-rich reforming gas can reduce costs, the CO present in such gas poisons the catalyst. A novel treatment method involves creating a mild hydrogen-deficient environment to enable rapid recovery from high-CO poisoning states. This approach utilizes dual-cell cycling to maintain stable operation in CO-containing environments, though research on this method remains limited. This study quantitatively analyzed the effects of CO concentration, back pressure, humidity, and temperature through multifactor experiments. A 100-h endurance test under periodic purging conditions revealed fundamentally different degradation pathways: CO exposure caused irreversible damage—a 14.29% loss in electrochemically active surface area, a 34.4% increase in charge transfer resistance, severe catalyst agglomeration, platinum particle growth reaching 55.6%, and oxidation significantly concentrated at the anode inlet due to CO concentration gradients. In contrast, hydrogen operation induced only minor degradation primarily attributable to cathode flooding. This study identified the dual effects of operating parameters, elucidated two distinct failure mechanisms, and provided critical insights for developing mitigation strategies, enabling PEMFC to operate continuously using impure hydrogen fuel.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100678"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147396225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The planning and operation of microgrids rely on efficient energy management, especially where the generation of renewable sources is high, intermittent, and unpredictable. The intermittent characteristics of solar energy and wind velocity pose a significant challenge in ensuring economic viability, voltage stability, and safe operation. In order to solve these problems, this paper suggests a Levy Flight Particle Swarm Optimization (LFPSO)-based techno-economic optimization model of optimal integration of wind, solar, micro-turbine distributed generators, and energy storage systems within a grid-connected micro-grid. The LFPSO is an extension of the traditional PSO that adds heavy-tailed Levy perturbations of flight, which greatly increases the possibility of world exploration as well as reduces premature convergence. The optimization model will reduce the levelized operating cost, system active power losses, and dependency of this substation at the same time, with nodal voltage magnitude and phase angle constraints to provide stable operation. The uncertainty of renewable generation is modeled explicitly by applying the scenario-based stochastic make-up of wind speed and solar irradiance. The validity of the methodology is demonstrated on an IEEE-13 bus microgrid under various conditions of renewable availability and load. Comparative convergence analysis has shown that LFPSO has a convergence time which is ten times less than standard PSO, and objective values are lower as well which is statistically validated with 100 independent runs showing robustness. The simulation results show that the operating cost is reduced to 0.142–0.145 USD/kWh, the active power loss is reduced by up to 80 percent under favorable conditions of renewable sources and the Substation Dependency Index (SBDI) is improved systematically, which is an indicator of better resilience of the microgrids. The findings affirm that LFPSO offers computationally efficient and robust optimization framework of microgrid energy management in the real world and has distinct benefits over its peer meta-heuristic approaches in addressing renewable uncertainty and multi-objective operational limitations.
{"title":"Improving microgrid reliability and performance by implementing novel optimizing strategies for renewable energy and storage devices","authors":"Nilesh Chothani , Parul Upadhyay , Dharmesh Patel , Choon Kit Chan , Nithesh Naik , Subhav Singh , Saurav Dixit","doi":"10.1016/j.nexus.2026.100671","DOIUrl":"10.1016/j.nexus.2026.100671","url":null,"abstract":"<div><div>The planning and operation of microgrids rely on efficient energy management, especially where the generation of renewable sources is high, intermittent, and unpredictable. The intermittent characteristics of solar energy and wind velocity pose a significant challenge in ensuring economic viability, voltage stability, and safe operation. In order to solve these problems, this paper suggests a Levy Flight Particle Swarm Optimization (LFPSO)-based techno-economic optimization model of optimal integration of wind, solar, micro-turbine distributed generators, and energy storage systems within a grid-connected micro-grid. The LFPSO is an extension of the traditional PSO that adds heavy-tailed Levy perturbations of flight, which greatly increases the possibility of world exploration as well as reduces premature convergence. The optimization model will reduce the levelized operating cost, system active power losses, and dependency of this substation at the same time, with nodal voltage magnitude and phase angle constraints to provide stable operation. The uncertainty of renewable generation is modeled explicitly by applying the scenario-based stochastic make-up of wind speed and solar irradiance. The validity of the methodology is demonstrated on an IEEE-13 bus microgrid under various conditions of renewable availability and load. Comparative convergence analysis has shown that LFPSO has a convergence time which is ten times less than standard PSO, and objective values are lower as well which is statistically validated with 100 independent runs showing robustness. The simulation results show that the operating cost is reduced to 0.142–0.145 USD/kWh, the active power loss is reduced by up to 80 percent under favorable conditions of renewable sources and the Substation Dependency Index (SBDI) is improved systematically, which is an indicator of better resilience of the microgrids. The findings affirm that LFPSO offers computationally efficient and robust optimization framework of microgrid energy management in the real world and has distinct benefits over its peer meta-heuristic approaches in addressing renewable uncertainty and multi-objective operational limitations.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100671"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147396688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Achieving universal electricity access in Senegal by 2030 remains a major policy challenge due to persistent spatial disparities in infrastructure, population density, and resource availability. This study conducts a nationwide, spatially explicit assessment of least-cost electrification pathways using OnSSET. The analysis develops context-specific scenarios to plan optimal technology mixes across rural and peri‑urban areas, based on differentiated tiers of electricity access. By integrating high-resolution geospatial, demographic, and techno-economic data, the model identifies the most economically viable solutions for achieving universal access. Results indicate that grid extension is the least-cost option for approximately 93.7 % of the population, largely concentrated in peri‑urban areas with high population density and proximity to existing grid infrastructure. In contrast, solar PV mini-grids (MG PV) and stand-alone PV (SA PV) systems are optimal for 0.7 % and 5.6 % of the population, respectively, mainly in remote, sparsely populated rural settlements. The total investment required to achieve universal electricity access by 2030 is estimated at USD 269.8 million, corresponding to 116.1 MW of additional installed capacity.
Beyond quantifying cost-optimal solutions, the study demonstrates the potential of open-source geospatial models like OnSSET to support transparent, data-driven planning in developing country contexts. It also highlights key policy implications, emphasizing the need for integrated national electrification strategies that combine centralized and decentralized systems to address regional disparities. Limitations of the study include uncertainties in input data quality, static demand assumptions, and the exclusion of non-technical barriers such as institutional capacity and financing constraints. Nonetheless, the findings provide a valuable decision-support basis for Senegal’s ongoing energy transition and broader Sustainable Development Goal 7 (SDG7) objectives.
{"title":"Least-cost electrification pathways for Senegal by 2030: A nationwide analysis using open-source spatial electrification tool (OnSSET)","authors":"Adama Sarr , Aldo Bischi , Umberto Desideri , Cheikh Mouhamed Fadel Kebe","doi":"10.1016/j.nexus.2025.100621","DOIUrl":"10.1016/j.nexus.2025.100621","url":null,"abstract":"<div><div>Achieving universal electricity access in Senegal by 2030 remains a major policy challenge due to persistent spatial disparities in infrastructure, population density, and resource availability. This study conducts a nationwide, spatially explicit assessment of least-cost electrification pathways using OnSSET. The analysis develops context-specific scenarios to plan optimal technology mixes across rural and peri‑urban areas, based on differentiated tiers of electricity access. By integrating high-resolution geospatial, demographic, and techno-economic data, the model identifies the most economically viable solutions for achieving universal access. Results indicate that grid extension is the least-cost option for approximately 93.7 % of the population, largely concentrated in peri‑urban areas with high population density and proximity to existing grid infrastructure. In contrast, solar PV mini-grids (MG PV) and stand-alone PV (SA PV) systems are optimal for 0.7 % and 5.6 % of the population, respectively, mainly in remote, sparsely populated rural settlements. The total investment required to achieve universal electricity access by 2030 is estimated at USD 269.8 million, corresponding to 116.1 MW of additional installed capacity.</div><div>Beyond quantifying cost-optimal solutions, the study demonstrates the potential of open-source geospatial models like OnSSET to support transparent, data-driven planning in developing country contexts. It also highlights key policy implications, emphasizing the need for integrated national electrification strategies that combine centralized and decentralized systems to address regional disparities. Limitations of the study include uncertainties in input data quality, static demand assumptions, and the exclusion of non-technical barriers such as institutional capacity and financing constraints. Nonetheless, the findings provide a valuable decision-support basis for Senegal’s ongoing energy transition and broader Sustainable Development Goal 7 (SDG7) objectives.</div></div>","PeriodicalId":93548,"journal":{"name":"Energy nexus","volume":"21 ","pages":"Article 100621"},"PeriodicalIF":9.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145747039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}