Energy Conversion and Management最新文献_第4页

Reliable quantification of liquid oxygenated products in CO2/CH4 plasma-catalytic conversion CO2/CH4等离子体催化转化中液态氧合产物的可靠定量

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-27 DOI: 10.1016/j.enconman.2026.121115

Noelia Merino , Maria Mikhail , Xavier Duten , Michael Tatoulian , Stéphanie Ognier

The direct conversion of CO₂ and CH₄ into oxygenated products via plasma catalysis offers a promising route for biogas valorization, generating molecules usable as fuels or fuel additives, or convertible into energy carriers. However, many studies lack rigor in the quantification of oxygenate selectivity, often leading to overestimations and misleading conclusions regarding catalyst performance and energy efficiency. Typically, gaseous products are analyzed online, while liquid products are collected and analyzed offline. Oxygenate selectivity is often estimated indirectly by subtracting selectivities of other carbon products from 100%, a method that lacks accuracy and tends to overestimate performance. This work highlights the need for accurate and reliable analytical approaches to provide a realistic assessment of plasma-assisted CO₂ and CH₄ conversion and guide future research. An improved experimental setup is proposed, keeping all products in the gas phase using a heated transfer line and enabling direct online quantification by gas chromatography directly after the reactor. This approach minimizes errors from incomplete condensation and indirect calculations, achieving a carbon balance close to 95%. Beyond analytical considerations, the conversion of CO₂ and CH₄ into oxygenated products by plasma catalysis remains a challenge. Results indicate that while catalysts enhance overall conversion, their effect on oxygenate selectivity is limited. These findings suggest that future work should focus on tailoring plasma conditions rather than solely on catalyst optimization. Overall, this study emphasizes the importance of robust analytical methods as a foundation for better understanding reaction mechanisms and for guiding future research on energy conversion by plasma catalysis.

通过等离子体催化将CO2和CH4直接转化为含氧产物，为沼气增值提供了一条很有前途的途径，可以产生可用作燃料或燃料添加剂的分子，也可以转化为能量载体。然而，许多研究在定量氧化选择性方面缺乏严谨性，往往导致对催化剂性能和能效的高估和误导性结论。通常，气体产品在线分析，而液体产品离线收集和分析。氧合物的选择性通常是通过从100%中减去其他碳产物的选择性来间接估计的，这种方法缺乏准确性并且倾向于高估性能。这项工作强调了对准确可靠的分析方法的需求，以提供等离子体辅助CO2和CH4转化的现实评估，并指导未来的研究。提出了一种改进的实验装置，使用加热传输线将所有产品保持在气相中，并在反应器后直接通过气相色谱进行直接在线定量。这种方法最大限度地减少了不完全冷凝和间接计算的误差，实现了接近95%的碳平衡。除了分析方面的考虑，通过等离子体催化将CO2和CH4转化为含氧产物仍然是一个挑战。结果表明，虽然催化剂提高了总转化率，但对氧选择性的影响有限。这些发现表明，未来的工作应侧重于调整等离子体条件，而不仅仅是催化剂优化。总的来说，本研究强调了强大的分析方法作为更好地理解反应机制和指导未来等离子体催化能量转换研究的基础的重要性。

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引用次数: 0

Synergistic integration of oxy-combustion and proton exchange membrane electrolysis for efficient green ammonia and clean energy co-production 全氧燃烧与质子交换膜电解协同集成，实现高效绿色氨和清洁能源联产

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-26 DOI: 10.1016/j.enconman.2026.121089

Binash Imteyaz , Mohd Bilal Naim Shaikh , Kashif Irshad , Mohamed A. Habib

Addressing global decarbonization and industrial energy demands, this study proposes a novel hybrid integrated system for co-producing green ammonia and clean power with inherent carbon capture. The system synergistically combines an oxy-combustion cycle, a proton exchange membrane water electrolyzer, a cryogenic air separation unit, and an ammonia synthesis reactor. The novelty of this work lies in the direct process integration of oxy-combustion, proton exchange membrane electrolysis, cryogenic air separation, and ammonia synthesis, enabling internal oxygen–nitrogen resource coupling and achieving thermodynamic synergies not previously quantified in the literature. A comprehensive thermodynamic, techno-economic, and environmental analysis was performed. Performance evaluation of the electrolyzer highlighted the trade-off between efficiency and production rates, influenced by current density and membrane thickness. For the oxy-combustion unit, optimal flue gas recirculation is critical for temperature control and maximizing power output, while the equivalence ratio greatly impacted cycle efficiency and net power generation. Crucially, the integrated design demonstrated significant efficiency gains: the ammonia production subsystem thermal efficiency increased from 41.3% to 45.1%, and the clean energy subsystem improved from 57.6% to 61.8% compared to standalone operations. Overall, the integrated system achieved an energy efficiency of 51.3% and an exergy efficiency of 53.5%. Annually, the system is projected to yield 192.9 MWh of clean energy and 50.8 t of green ammonia. Although the integrated configuration is evaluated at a pilot scale, normalization shows that the system corresponds to approximately 1,693 t of ammonia per year per megawatt of installed oxy-combustion capacity, demonstrating scalability of the proposed approach. Techno-economic assessment estimated the levelized cost of ammonia at $723.3/t and the levelized cost of electricity at $123.6/MWh, costs competitive within emerging green technologies. This research validates the thermodynamic superiority and techno-economic promise of holistic integration, offering a template for next-generation systems that align industrial processes with net-zero emission targets.

针对全球脱碳和工业能源需求，本研究提出了一种新型混合集成系统，用于共同生产具有固有碳捕获的绿色氨和清洁电力。该系统协同结合了一个氧燃烧循环、一个质子交换膜水电解槽、一个低温空气分离装置和一个氨合成反应器。这项工作的新颖之处在于氧燃烧、质子交换膜电解、低温空气分离和氨合成的直接过程集成，实现了内部氧氮资源耦合，实现了以前文献中未量化的热力学协同效应。进行了综合热力学、技术经济和环境分析。电解槽的性能评估强调了效率和生产率之间的权衡，受电流密度和膜厚度的影响。对于全氧燃烧机组来说，优化烟气再循环是控制温度和最大输出功率的关键，而等效比对循环效率和净发电量有很大影响。至关重要的是，集成设计显示出显著的效率提升：与独立运行相比，氨生产子系统的热效率从41.3%提高到45.1%，清洁能源子系统从57.6%提高到61.8%。总体而言，综合系统的能源效率为51.3%，火用效率为53.5%。每年，该系统预计将产生192.9兆瓦时的清洁能源和50.8吨的绿色氨。虽然综合配置是在中试规模上进行评估的，但标准化表明，该系统相当于每兆瓦安装的氧燃烧能力每年约1,693吨氨，这表明了拟议方法的可扩展性。技术经济评估估计，氨的平准化成本为723.3美元/吨，电力的平准化成本为123.6美元/兆瓦时，在新兴的绿色技术中具有竞争力。这项研究验证了整体集成的热力学优势和技术经济前景，为下一代系统提供了一个模板，使工业过程与净零排放目标保持一致。

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引用次数: 0

Innovative biomass-driven pathways for green ammonia and urea production with integration of carbon capture 创新生物质驱动的绿色氨和尿素生产途径与碳捕获的整合

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121099

Dogan Erdemir, Ibrahim Dincer

Urea and ammonia are vital fertilizers traditionally produced via the fossil-fuel-intensive Haber-Bosch process, which accounts for significant global carbon dioxide emissions. Transitioning to green ammonia and urea production is essential for sustainable agriculture and meeting the climate goals through the integration of renewable energy and carbon capturing technologies. This study investigates the feasibility of a biomass-driven system to achieve carbon–neutral synthesis while addressing the challenge of significant elemental variability in biomass feedstocks. A thermodynamic analysis is performed on 86 different biomass sources to evaluate an integrated system comprising oxy-combustion power generation, carbon capture, ammonia synthesis, and urea production across two distinct operational modes: a self-sufficient mode, and an hybrid mode that uses external energy to utilize all remaining carbon dioxide. In self-sufficient mode, the system produces a constant 118.7 kg of urea per 1 MWh of electricity using a median of 4.8 tons of feedstock, while the hybrid mode utilizes remaining carbon to produce an additional 1.25 tons of urea at a massive energy cost of 16,100 kWh. The findings demonstrate that while the system is technically viable, its economic feasibility is critically dependent on securing off-peak electricity rates of approximately $0.039/kWh to bring production costs in line with global market benchmarks.

尿素和氨是重要的肥料，传统上是通过化石燃料密集型的哈伯-博世工艺生产的，该工艺占全球二氧化碳排放量的很大一部分。向绿色氨和尿素生产过渡对于可持续农业和通过整合可再生能源和碳捕获技术实现气候目标至关重要。本研究探讨了生物质驱动系统实现碳中性合成的可行性，同时解决了生物质原料中显著元素变化的挑战。对86种不同的生物质资源进行了热力学分析，以评估一个综合系统，该系统包括氧燃烧发电、碳捕获、氨合成和尿素生产，跨越两种不同的运行模式：自给自足模式和使用外部能源利用所有剩余二氧化碳的混合模式。在自给自足模式下，该系统每兆瓦时发电产生118.7公斤尿素，平均使用4.8吨原料，而混合模式利用剩余的碳产生额外的1.25吨尿素，能源成本为16,100千瓦时。研究结果表明，虽然该系统在技术上是可行的，但其经济可行性严重依赖于确保约0.039美元/千瓦时的非高峰电价，以使生产成本符合全球市场基准。

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引用次数: 0

Dynamic assessment of electrification pathways for heating and hot water in Korean Multi-Family residential buildings 韩国多户住宅供暖和热水电气化途径的动态评估

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121107

Daneun Kim , Juneyeol Jung , Jaeheuk Choi , Hoseong Lee

The electrification of heating and domestic hot-water systems in Korean multi-family residential buildings is not well understood, as most studies overlook their distinct hydronic features—low-temperature radiant-floor heating, synchronized DHW demand, and large vertical distribution losses. This study develops an integrated TRNSYS-based dynamic framework that captures these constraints and evaluates stepwise electrification pathways rather than only end-state systems. After screening key design variables to establish realistic boundary conditions, four transition scenarios are assessed: a boiler baseline, a hybrid retrofit with central ASHP DHW, a mixed system with individual ASHP heating and central DHW, and a fully individual ASHP configuration. Results show that the fully individual system delivers the highest seasonal efficiency, reducing primary energy use and CO₂ emissions by up to 43% and 41% relative to the baseline. Intermediate stages also offer practical benefits, with hybrid and mixed configurations improving feasibility and reducing gas use under existing hydronic constraints. Overall, the study provides a practical and context-specific assessment framework for electrifying high-density apartment buildings, emphasizing that effective decarbonization requires staged, system-specific transition strategies tailored to Korean building conditions.

韩国多户住宅供暖和生活热水系统的电气化尚未得到很好的了解，因为大多数研究忽略了其独特的流体动力学特征-低温辐射地板采暖，同步DHW需求和大的垂直分布损耗。本研究开发了一个集成的基于trnsys的动态框架，该框架可以捕获这些限制并评估逐步电气化途径，而不仅仅是最终状态系统。在筛选关键设计变量以建立现实的边界条件后，评估了四种过渡方案：锅炉基线，中央空气源热泵DHW的混合改造，单个空气源热泵供暖和中央DHW的混合系统，以及完全独立的空气源热泵配置。结果表明，完全独立的系统提供了最高的季节性效率，相对于基线，减少了43%和41%的一次能源使用和二氧化碳排放。中间阶段也具有实际的优势，混合和混合配置提高了可行性，并减少了现有水力限制下的天然气使用。总体而言，该研究为高密度公寓楼的电气化提供了一个实用的、特定于环境的评估框架，强调有效的脱碳需要根据韩国建筑条件量身定制的分阶段、系统特定的过渡策略。

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引用次数: 0

Intensified turbulent thermal convection with reversible reactive fluid 可逆反应流体强化湍流热对流

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121111

Ran Yao, Sajad Jafari, Christophe Duwig

Enhancing heat transfer in turbulent convection has been a long-standing challenge in many energy and industrial processes. However, despite decades of efforts, conventional strategies have achieved only limited success, due to the intrinsic bounds of turbulent mixing. Inspired by thermal-chemical energy conversion, this work unlocks a fundamentally new route for intensified heat transfer by introducing a reversible chemical reaction (N₂O₄ ↔ 2NO₂) into Rayleigh-Bénard convection. The resulting reactive convection achieves an unprecedented increase in heat transfer (over seven times) relative to conventional non-reactive fluids. The underlying mechanism is described by a simplified double-film model: heat is absorbed as chemical energy in an endothermic film near the heated wall, then transported by reaction-intensified turbulence, and finally releases in an exothermic film near the cold wall. Unsteady analysis further confirms the coupling between chemical reaction and turbulence, particularly the coherent structures. Beyond advancing thermal convection theory, the approach offers practical potential for low-temperature waste-heat recovery where reaction reversibility is maintained, and for the design of gaseous space thermal management system.

在许多能源和工业过程中，增强湍流对流中的传热一直是一个长期存在的挑战。然而，尽管经过了几十年的努力，由于湍流混合的固有界限，传统策略只取得了有限的成功。受热化学能转换的启发，这项工作通过将可逆化学反应（N2O4↔2NO2）引入瑞利-巴萨纳德对流，为强化传热开辟了一条全新途径。与传统的非反应性流体相比，由此产生的反应性对流实现了前所未有的传热增加（超过7倍）。其基本机理用一个简化的双膜模型来描述：热作为化学能在靠近加热壁的吸热膜中被吸收，然后通过反应强化的湍流传递，最后在靠近冷壁的放热膜中释放。非定常分析进一步证实了化学反应与湍流之间的耦合，特别是相干结构。除了推进热对流理论之外，该方法还为保持反应可逆性的低温废热回收以及气体空间热管理系统的设计提供了实践潜力。

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引用次数: 0

A comparative conceptual analysis of CO2 heat pump dryers with closed-loop and open-loop air cycles 二氧化碳热泵干燥机的闭环和开环空气循环的概念比较分析

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121093

Jay Wang

This study has comprehensively compared and analysed CO₂ heat pump dryers operating under closed-loop and open-loop air cycles to evaluate their energy efficiency and drying performance. Unlike the conventional closed-loop air cycle that uses dry recirculated air as its inlet, the open-loop air cycle operates only with fresh ambient air. The physical models and working principles have been illustrated using psychrometric charts, and the influence of moisture variation has been considered in the fin-and-tube heat exchanger design for both the gas cooler and the evaporator. In the case study under typical hot and humid climate conditions (ambient temperature of 40 °C), the simulation compares three cycles over an air mass flow rate ranging from 0.5 kg/s to 1 kg/s. The open-loop air cycle with a wet air outlet achieves the largest heating capacity, i.e.: 17.44 kW at 1 kg/s, because the air is cooled in the evaporator first, allowing a greater temperature rise in the gas cooler. The open-loop air cycle with a dry air outlet produces the highest air temperature after the gas cooler, i.e.: 60.8 °C at 0.5 kg/s, which increases the air’s moisture absorption capacity. Compared with the closed-loop air cycle, the open-loop air cycle with dry air outlet proves more efficient for drying, delivering a shorter drying time (27.77 min at 0.5 kg/s) and a higher drying efficiency (0.8640 kg/kWh at 0.5 kg/s). Although the open-loop air cycle with a wet air outlet achieves the highest coefficient of performance of 2.31 at 1 kg/s, its drying performance declines obviously at higher mass flow rates, with specific moisture extraction rate dropping to 0.0767 kg/kWh. Overall, the configuration of open-loop air cycle with dry air outlet is the superior option, as it combines the shortest drying time and the highest specific moisture extraction rate, which are two critical metrics for heat pump dryers.

本研究全面比较和分析了在闭环和开环空气循环下运行的CO2热泵烘干机，以评估其能源效率和干燥性能。与传统的使用干燥再循环空气作为入口的闭环空气循环不同，开环空气循环只使用新鲜的环境空气。用干湿图说明了物理模型和工作原理，并在气体冷却器和蒸发器的翅片管式换热器设计中考虑了湿度变化的影响。在典型湿热气候条件下（环境温度为40°C）的案例研究中，模拟比较了空气质量流速从0.5 kg/s到1 kg/s的三个循环。带湿风出口的开环空气循环以1kg /s的速度获得最大的供热能力，即：17.44 kW，因为空气首先在蒸发器中冷却，使得气体冷却器中的温度上升幅度更大。干燥出风口的开环空气循环在冷却器后产生的最高空气温度为：0.5 kg/s下的60.8℃，增加了空气的吸湿能力。与闭环空气循环相比，带干风出口的开环空气循环的干燥效率更高，干燥时间更短（0.5 kg/s时为27.77 min），干燥效率更高（0.5 kg/s时为0.8640 kg/kWh）。虽然带湿风出口的开环空气循环在1 kg/s时的性能系数最高，达到2.31，但在较高的质量流量下，其干燥性能明显下降，比抽湿率降至0.0767 kg/kWh。总的来说，带干风出口的开环空气循环配置是优越的选择，因为它结合了最短的干燥时间和最高的比湿提取率，这是热泵干燥机的两个关键指标。

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引用次数: 0

A PCM based finned heat sink coupled with a finned heat pipe is an efficient thermal management option for portable electronic gadgets 基于PCM的翅片散热器与翅片热管相结合，是便携式电子设备的有效热管理选择

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121118

Bikash Kumar, Y. Naresh, J. Banerjee

Efficient thermal regulation of compact electronic devices remains a critical challenge as power densities continue to increase, necessitating effective passive cooling solutions. In PCM-based thermal management systems, the discharge cycle is just as important as the charging cycle, but it is often not studied enough. This work experimentally investigates in detail four different configurations of a heat sink (HS) with a phase change material (PCM): (i) a PCM-filled heat sink (PHS), (ii) a PCM-filled finned heat sink (PFHS), (iii) a PCM-filled finned heat sink integrated with a heat pipe (PFHSHP), and (iv) a PCM-filled finned heat sink coupled with a finned heat pipe (PFHSFHP). Docosane is the selected phase change material, and the tests are carried out at different power inputs (6, 8, 10, and 12 W) and controlled surrounding temperatures (24, 26, and 28 °C). The findings reveal that thermal performance depends to a large extent on the configuration and ambient conditions, and better performance is achieved at surrounding temperature of 24 °C. Among the investigated designs, the PFHSFHP configuration consistently exhibits the best charging and discharging performance across all operating conditions. For example, at an 8 W power level and S_T = 28 °C, the percentage improvement in charging time in PFHSFHP compared to PHS, PFHS, and PFHSHP is 35.49 %, 34.06 %, and 27.54 % respectively. Under the same conditions, the percentage reduction in discharging time is 30.94 %, 18.78 %, and 11.99 % respectively. The performance increase is mainly due to better heat spreading and faster heat rejection, which were made possible by the finned condenser section of the heat pipe, which maintained a higher thermal driving potential during both the melting and solidification of the PCM. Energy-based thermodynamic analysis further confirms the dominant role of the heat pipe in heat transport, particularly during the discharging phase. In summary, the PFHSFHP setup is a powerful and reliable passive thermal management method that can be utilized for the next generation of miniaturized electronic devices, offering extended thermal buffering, accelerated heat dissipation, and enhanced operational stability.

随着功率密度的不断增加，小型电子设备的高效热调节仍然是一个关键的挑战，需要有效的被动冷却解决方案。在基于pcm的热管理系统中，放电周期与充电周期同样重要，但通常研究不够。本研究通过实验详细研究了相变材料（PCM）的四种不同结构的散热器（HS）：(i)填充PCM的散热器（PHS），（ii）填充PCM的翅片散热器（PFHS），（iii）填充PCM的翅片散热器与热管集成（PFHSHP），以及（iv）填充PCM的翅片散热器与翅片热管耦合（PFHSFHP）。Docosane是所选的相变材料，测试在不同的功率输入（6、8、10和12 W）和受控的环境温度（24、26和28°C）下进行。研究结果表明，热性能在很大程度上取决于结构和环境条件，在24°C的环境温度下可以获得更好的性能。在所研究的设计中，PFHSFHP配置在所有操作条件下始终表现出最佳的充放电性能。例如，在8 W功率和温度为28°C时，PFHSFHP与PHS、PFHS和PFHSHP相比，充电时间的改善百分比分别为35.49%、34.06%和27.54%。在相同条件下，放电时间分别缩短30.94%、18.78%和11.99%。性能的提高主要是由于热管的翅片冷凝器段在PCM熔化和凝固过程中都保持了较高的热驱动势，从而实现了更好的传热和更快的散热。基于能量的热力学分析进一步证实了热管在热传递中的主导作用，特别是在放电阶段。总之，PFHSFHP装置是一种强大而可靠的被动热管理方法，可用于下一代小型化电子设备，提供扩展的热缓冲、加速的散热和增强的运行稳定性。

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引用次数: 0

Selection of underground hydrogen storage systems using a novel fuzzy model 基于模糊模型的地下储氢系统选择

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121082

Ömer Faruk Görçün , Gülay Demir , Dragan Pamucar , Vladimir Simic

<div><div>Storing hydrogen resources underground can accelerate the transition to renewable energy, facilitate energy supply security, and the adoption and expansion of hydrogen energy, a clean energy source. The selection of sustainable underground hydrogen storage systems is a critical research topic for addressing environmental issues caused using fossil fuels. However, decision-makers still lack a consensus-based and sustainability-oriented framework that can comparatively evaluate alternative underground hydrogen storage geological formations under economic, environmental, social, and technical uncertainties, which constitutes a critical barrier to large-scale hydrogen deployment. This issue has become more prominent as fossil-based fuel reserves are gradually decreasing worldwide. In contrast, researchers and practitioners lack a consensus on which underground storage method is most suitable for economical, safe, and efficient hydrogen storage. If this problem is not addressed correctly and reasonable solutions are not obtained, continued dependence on fossil fuels may persist. Alternatively, other renewable energy sources with relatively lower efficiency and performance may be adopted. In both cases, significant delays in achieving the global sustainability goal are likely to occur. We propose an integrated fuzzy decision-making framework (F-WENSLO & Dombi-Bonferroni & F-ARTASI) to address this selection problem under uncertainty. The proposed framework integrates fuzzy WENSLO (Weights by ENvelope and SLOpe) for robust sustainability-based criteria weighting, the Dombi–Bonferroni aggregation operator to model interdependencies among criteria explicitly, and the fuzzy ARTASI (Alternative Ranking Technique based on Adaptive Standardized Intervals) method to provide flexible and stable ranking of geological alternatives beyond rigid distance-based approaches. Key advantages of the proposed model include producing reliable and consistent solutions that accurately reflect real-world conditions for selecting sustainable underground hydrogen storage systems. The results revealed that C14 (job creation and employment opportunities) (0.0603) is the most influential criterion in selecting the most suitable storage system. In addition, salt caverns with an <span><math><mrow><msub><mi>Ω</mi><mi>i</mi></msub></mrow></math></span> of 10,5167 have achieved the highest score, placing them in the first position, and it is the most suitable and advantageous underground hydrogen storage option. The suggested decision-making tool can yield reliable and robust solutions in real-world conditions, enabling the planning of infrastructure design for hydrogen energy systems that incorporate sustainability dimensions. In that regard, the developed model possesses the characteristics of an efficient and practical roadmap that can guide policymakers and decision-makers in transitioning from fossil-based energy sources to renewable energy sources. It has been i

地下储氢可以加速向可再生能源的过渡，促进能源供应安全，以及氢能源这一清洁能源的采用和扩大。选择可持续的地下储氢系统是解决化石燃料使用造成的环境问题的关键研究课题。然而，决策者仍然缺乏一个以共识为基础、以可持续为导向的框架，可以在经济、环境、社会和技术不确定性的情况下对可供选择的地下储氢地质构造进行比较评估，这是大规模氢部署的关键障碍。随着世界范围内化石燃料储量的逐渐减少，这一问题变得更加突出。相比之下，研究人员和实践人员对哪种地下储氢方式最适合经济、安全、高效的储氢方式缺乏共识。如果这个问题没有得到正确的处理和合理的解决办法，对化石燃料的持续依赖可能会持续下去。也可以采用其他效率和性能相对较低的可再生能源。在这两种情况下，在实现全球可持续性目标方面可能会出现重大延误。我们提出了一个综合模糊决策框架（F-WENSLO & Dombi-Bonferroni & F-ARTASI）来解决不确定性下的选择问题。所提出的框架集成了模糊WENSLO（包络线和斜率加权），用于稳健的基于可持续性的标准加权，Dombi-Bonferroni聚合算子用于明确地模拟标准之间的相互依赖性，模糊ARTASI（基于自适应标准化区间的备选排序技术）方法提供灵活和稳定的地质备选排序，超越了基于刚性距离的方法。该模型的主要优点包括提供可靠和一致的解决方案，准确反映选择可持续地下储氢系统的现实条件。结果表明，C14（就业创造和就业机会）（0.0603）对选择最合适的仓储系统影响最大。另外，盐穴的Ωi得分最高，为10,5167，位居第一，是最合适、最有利的地下储氢选择。建议的决策工具可以在现实条件下产生可靠和强大的解决方案，使氢能源系统的基础设施设计规划能够纳入可持续性维度。在这方面，开发的模型具有有效和实用的路线图的特点，可以指导政策制定者和决策者从化石能源向可再生能源过渡。它已经被用于评估地下地质构造，可以促进地下氢能的储存，作为一个案例研究。该工具的可靠性和健壮性已通过广泛的验证测试得到验证。

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引用次数: 0

Research on the performance and mode switching strategy of the photovoltaic/thermal-air dual heat source direct expansion heat pump system based on micro heat pipe arrays 基于微热管阵列的光伏/热空气双热源直扩热泵系统性能及模式切换策略研究

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121125

Ze Bai , Yaohua Zhao , Zhenhua Quan , Yiyang Liu , Wanli Chang

Conventional flat-plate photovoltaic/thermal (PVT) modules suffer from low solar energy utilization efficiency and unstable heat supply when used as heat pump evaporators. Additionally, their heat dissipation capabilities are limited when used as condensers. To address these limitations, this study proposes a novel micro heat pipe array-integrated PVT–air evaporator/condenser (MHPA-PVTAE/C), coupled with a dual-source direct expansion heat pump. Seasonal experiments were conducted to characterize its trigeneration performance, and an adaptive heating-mode switching strategy was developed using the coefficient of performance for heating (COP(H)) as the optimization objective based on solar irradiance and ambient temperature. The system achieved a COP(H) of 6.2 (summer) and 4.9 (winter), power generation efficiency of up to 14%, and a COP(C) of 2.7. Throughout continuous multi-day tests, the compressor exhaust temperature remained below 90 °C, and the suction/exhaust pressure variation rates were both below 5%, demonstrating reliable and stable operation when the MHPA-PVTAE/C functioned as the evaporator or condenser. Compared with existing systems, the novel system enhanced the COP(H) by 13.1–68.1% (summer) and 15.3–75.2% (winter), and increased the COP(C) by 5.2–42.4%, providing a validated technical route for building-scale trigeneration system.

传统平板光伏/热（PVT）组件作为热泵蒸发器使用时，存在太阳能利用效率低、供热不稳定等问题。此外，当用作冷凝器时，它们的散热能力受到限制。为了解决这些限制，本研究提出了一种新型微型热管阵列集成pvt -空气蒸发器/冷凝器（MHPA-PVTAE/C），再加上双源直接膨胀热泵。通过季节性实验对其三联产性能进行表征，并基于太阳辐照度和环境温度，以供热性能系数（COP(H)）为优化目标，提出了一种自适应供热模式切换策略。该系统夏季COP(H)为6.2，冬季COP(H)为4.9，发电效率高达14%，COP(C)为2.7。在连续多天的试验中，压缩机排气温度保持在90℃以下，吸排气压力变化率均低于5%，表明MHPA-PVTAE/C作为蒸发器或冷凝器时运行可靠稳定。与现有系统相比，该系统夏季COP(H)和冬季COP(C)分别提高13.1 ~ 68.1%和15.3 ~ 75.2%，COP(C)分别提高5.2 ~ 42.4%，为建筑规模三联供系统提供了一条行之有效的技术路线。

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引用次数: 0

Semi-supervised anomaly detection in photovoltaic systems under power tracking mode 电力跟踪模式下光伏系统的半监督异常检测

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-01-24 DOI: 10.1016/j.enconman.2026.121114

Fouzi Harrou , Abdelkader Dairi , Abdelhakim Dorbane , Bilal Taghezouit , Ying Sun

Fault detection in grid-connected photovoltaic (GCPV) systems is critical for ensuring operational safety and efficiency, yet the availability of labeled fault data in real-world deployments is limited. Reliable anomaly detection in GCPV systems is vital for ensuring operational safety, minimizing energy losses, and maintaining efficiency. This study presents a systematic, mode-aware benchmarking of semi-supervised anomaly detection methods for GCPV monitoring under realistic operating conditions. This study evaluates four semi-supervised techniques, Isolation Forest (iForest), Local Outlier Factor (LOF), One-Class SVM (1SVM), and Elliptic Envelope (EE), for fault detection in GCPV systems operating under Intermediate and Maximum Power Point Tracking (IPPT/MPPT) modes. Using the GPVS-Faults dataset, which contains simulated fault scenarios generated from a grid-connected PV system emulator, all models are trained exclusively on fault-free data, following a strictly semi-supervised paradigm, and evaluated across multiple metrics, including accuracy, F1-score, AUC, and false positive rate (FPR). Experimental results show that EE achieves the best average accuracy and AUC with the lowest FPR across both operating modes, reaching an average accuracy of 94.68% under MPPT and 93.54% under IPPT. LOF exhibits the highest sensitivity and F1-score, but at the expense of increased false positives, while iForest provides a balanced trade-off between precision and recall. Beyond detection performance, this work emphasizes reproducibility and interpretability in semi-supervised PV fault detection. To enhance transparency, SHapley Additive exPlanations (SHAP) analysis is used as a post-hoc interpretability layer based on an auxiliary XGBoost model, revealing fault-specific feature contributions aligned with physical system behavior. Overall, the results demonstrate complementary strengths among the evaluated methods and highlight the effectiveness of EE for low-false-alarm fault detection, alongside the value of lightweight, explainable, and mode-aware semi-supervised frameworks in supporting GCPV monitoring.

并网光伏（GCPV）系统的故障检测对于确保运行安全和效率至关重要，但实际部署中标记故障数据的可用性有限。在GCPV系统中，可靠的异常检测对于确保运行安全、最大限度地减少能量损失和保持效率至关重要。本研究提出了一种系统的、模式感知的半监督异常检测方法的基准测试，用于GCPV在实际运行条件下的监测。本研究评估了隔离森林（ifforest）、局部离群因子（LOF）、一类支持向量机（1SVM）和椭圆包络（EE）四种半监督技术在GCPV系统中故障检测中的应用，这些技术在中间和最大功率点跟踪（IPPT/MPPT）模式下运行。使用GPVS-Faults数据集（包含由并网光伏系统模拟器生成的模拟故障场景），所有模型都只在无故障数据上进行训练，遵循严格的半监督范式，并通过多个指标进行评估，包括准确性、f1分数、AUC和假阳性率（FPR）。实验结果表明，在两种工作模式下，EE的平均准确率和AUC均达到最佳，FPR最低，在MPPT下平均准确率为94.68%，在IPPT下平均准确率为93.54%。LOF表现出最高的灵敏度和f1得分，但代价是假阳性增加，而ifforest在精度和召回率之间提供了平衡的权衡。除了检测性能，这项工作还强调了半监督式光伏故障检测的再现性和可解释性。为了提高透明度，SHapley加性解释（SHAP）分析被用作基于辅助XGBoost模型的事后可解释性层，揭示与物理系统行为一致的故障特定特征贡献。总体而言，结果显示了评估方法之间的互补优势，并突出了EE在低误报故障检测方面的有效性，以及轻量级、可解释和模式感知的半监督框架在支持GCPV监测方面的价值。

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引用次数: 0