China, People’s Republic

The integration of renewable energy resources (RES) into microgrids (MGs) poses significant challenges due to the intermittent nature of generation and the increasing complexity of multi-energy scheduling. To enhance operational flexibility and reliability this paper proposes an intelligent energy management system (EMS) for MGs incorporating a hybrid hydrogen-battery energy storage system (HHB-ESS). The system model jointly considers the complementary characteristics of short-term and long-term storage technologies. Three conflicting objectives are defined: economic cost (EC) system response stability and battery life loss (BLO). To address the challenges of multi-objective trade-offs and heterogeneous storage coordination a novel deep-reinforcement-learning (DRL) algorithm termed MOATD3 is developed based on a dynamic reward adjustment mechanism (DRAM). Simulation results under various operational scenarios demonstrate that the proposed method significantly outperforms baseline methods achieving a maximum improvement of 31.4% in SRS and a reduction of 46.7% in BLO.

Hydrogen is an ideal energy carrier in future applications due to clean byproducts and high efciency. However many challenges remain in the application of hydrogen including hydrogen production delivery storage and conversion. In terms of hydrogen storage two compression modes (mechanical and non-mechanical compressors) are generally used to increase volume density in which mechanical compressors with several classifcations including reciprocating piston compressors hydrogen diaphragm compressors and ionic liquid compressors produce signifcant noise and vibration and are expensive and inefcient. Alternatively non-mechanical compressors are faced with issues involving large-volume requirements slow reaction kinetics and the need for special thermal control systems all of which limit large-scale development. As a result modular safe inexpensive and efcient methods for hydrogen storage are urgently needed. And because electrochemical hydrogen compressors (EHCs) are modular highly efcient and possess hydrogen purifcation functions with no moving parts they are becoming increasingly prominent. Based on all of this and for the frst time this review will provide an overview of various hydrogen compression technologies and discuss corresponding structures principles advantages and limitations. This review will also comprehensively present the recent progress and existing issues of EHCs and future hydrogen compression techniques as well as corresponding containment membranes catalysts gas difusion layers and fow felds. Furthermore engineering perspectives are discussed to further enhance the performance of EHCs in terms of the thermal management water management and the testing protocol of EHC stacks. Overall the deeper understanding of potential relationships between performance and component design in EHCs as presented in this review can guide the future development of anticipated EHCs.

In response to the global climate change and the need for green and low-carbon development hydrogen energy has been recognized as a clean energy source that can achieve carbon neutrality unlike fossil fuels. As a country with a shortage of energy resources the development of hydrogen energy is of significant importance for China to adjust its energy structure and accelerate the new era of energy transformation. Based on the development of China’s hydrogen energy industry this paper elaborates on the current status and development trends of key technologies in the entire industrial chain of hydrogen energy in various stages including production storage transportation and application and identifies the problems and challenges of hydrogen energy development. The paper focuses on the analysis of hydrogen storage and transportation application scenarios and clarifies the selection of hydrogen storage and transportation technologies in different scenarios. To achieve healthy devel opment of China’s hydrogen energy industry it is necessary to strengthen top-level design make strategic planning encourage large-scale state-owned energy enterprises to play a leading role promote the development of the entire industry chain increase technological research and development efforts prevent the risk of core technology constraints and vigorously promote the application of hydrogen energy to realize the construction of a hydrogen energy society.

To enhance the accommodation capacity of renewable energy and promote the coordinated development of multiple energy this paper proposes a novel economic dispatch method for an integrated electricity–heat–hydrogen energy system on the basis of coupling three energy flows. Firstly we develop a mathematical model for the hydrogen energy system including hydrogen production storage and hydrogen fuel cells. Additionally a multi-device combined heat and power system is constructed incorporating gas boilers waste heat boilers gas turbines methanation reactors thermal storage tanks batteries and gas storage tanks. Secondly to further strengthen the carbon reduction advantages the economic dispatch model incorporates the power-to-gas process and carbon trading mechanisms giving rise to minimizing energy purchase costs energy curtailment penalties carbon trading costs equipment operation and maintenance costs. The model is linearized to ensure a global optimal solution. Finally the experimental results validate the effectiveness and superiority of the proposed model. The integration of electricity–hydrogen coupling devices improves the utilization rate of renewable energy generation and reduces the total system operating costs and carbon trading costs. The use of a tiered carbon trading mechanism decreases natural gas consumption and carbon emissions contributing to energy conservation and emission reduction.

China as both a major energy consumer and the largest carbon emitter globally views carbon capture utilization and storage (CCUS) hydrogen production as a crucial and innovative technology for achieving its dual carbon goals of carbon peaking and carbon neutrality. The development of such technologies requires strong policy guidance making the quantification of policy pathways essential for understanding their effectiveness. This study employs a data-driven framewor integrating LDA topic modeling and the PMC-TE index to analyze the regional and temporal dynamics of CCUS-hydrogen development policies. The research identifies 16 optimal policy topics highlighting gaps in policy design and implementation. The analysis uncovers significant fragmentation in policy pathways with supply-side policies receiving disproportionate attention while demand-side and environmental policies remain under-supported. Regional disparities are evident with wealthier provinces showing higher policy engagement compared to underdeveloped regions. The study also reveals that policy evolution has been largely reactive emphasizing the need for a more proactive and consistent long-term strategy. These findings provide valuable insights for creating more balanced integrated and regionally tailored policy approaches to effectively drive CCUS-hydrogen development in China.

With the large-scale deployment of renewable energy the issue of wind power consumption has become increasingly prominent leading to serious wind energy abandonment. In order to promote energy sustainability this paper proposes a low-carbon economic scheduling model of an integrated energy system (IES) that combines the flexible supply–demand response with the diversified utilization of hydrogen energy. A mixedinteger linear programming model is developed and solved using the commercial solver GUROBI to obtain the scheduling scheme that minimizes total costs. First decoupling analysis is performed for combined heat and power (CHP) units and the organic Rankine cycle (ORC) is introduced to enable dynamic output adjustments. On the demand side a flexible demand response mechanism is introduced which allows various types of loads to transfer within the scheduling cycle or substitute for each other within the same period. Additionally combining the clean characteristics of hydrogen this paper introduces hydrogen-doped CHP and other utilization strategies and develops a diversified utilization structure of hydrogen. A small IES is used for case analysis to verify the effectiveness of the above strategies. The results show that the proposed strategy can entirely consume wind power reduce total cost by 21.32% and decrease carbon emissions by 44.83% thereby promoting low-carbon economic operation and sustainable energy development of the system.

Promoting the development of China’s hydrogen energy industry is crucial for achieving green energy transition. However existing research lacks systematic studies on the spatial layout of the hydrogen industry chain. This study constructed a comprehensive theoretical framework encompassing hardware infrastructure software systems and soft power. Using multi-source heterogeneous data GIS analysis and NVivo text coding methods the current regional layout and challenges of China’s hydrogen infrastructure industry chain were systematically evaluated. The findings determined that economically developed eastern regions lead in infrastructure and soft power while central and western regions leverage their resource and manufacturing advantages. Major challenges include regional imbalances in hardware infrastructure uneven distribution of soft power and misalignment between software systems and actual needs. Analysis of the “14th Five-Year Plan” of various regions elucidated deep insights into the diversity of local hydrogen energy development strategies identifying five types of hydrogen cities: resource-advantaged market-oriented regionally collaborative innovation-driven and policy-supported. Accordingly strategies to enhance industry chain synergy clarify city roles and optimize regional ecosystems were proposed. It is recommended to integrate hydrogen infrastructure with urban planning and incorporate environmental impact assessments into spatial optimization decisions. This study provides a systematic analytical framework and progressive policy recommendations for the efficient and green layout of China’s hydrogen infrastructure offering important implications for the sustainable development of the hydrogen industry and other rapidly developing economies.

Liquid hydrogen storage is an important way of hydrogen storage and transportation which greatly improves the storage and transportation efficiency due to the high energy density but at the same time brings new safety hazards. In this study the liquid hydrogen leakage in the storage area of a hydrogen production station is numerically simulated. The effects of ambient wind direction wind speed leakage mass flow rate and the mass fraction of gas phase at the leakage port on the diffusion behavior of the liquid hydrogen leakage were investigated. The results show that the ambient wind direction directly determines the direction of liquid hydrogen leakage diffusion. The wind speed significantly affects the diffusion distance. When the wind speed is 6 m/s the diffusion distance of the flammable hydrogen cloud reaches 40.08 m which is 2.63 times that under windless conditions. The liquid hydrogen leakage mass flow rate and the mass fraction of the gas phase have a greater effect on the volume of the flammable hydrogen cloud. As the leakage mass flow rate increased from 5.15 kg/s to 10 kg/s the flammable hydrogen cloud volume increased from 5734.31 m3 to 10305.5 m3 . The installation of a barrier wall in front of the leakage port can limit the horizontal diffusion of the flammable hydrogen cloud elevate the diffusion height and effectively reduce the volume of the flammable hydrogen cloud. This study can provide theoretical support for the construction and operation of hydrogen production stations.

This study proposes four kinds of hybrid source–grid–storage systems consisting of pho‐ tovoltaic and wind energy and a power grid including different batteries and hydrogen storage systems for Sanjiao town. HOMER‐PRO was applied for the optimal design and techno‐economic analysis of each case aiming to explore reproducible energy supply solutions for China’s industrial clusters. The results show that the proposed system is a fully feasible and reliable solution for in‐ dustry‐based towns like Sanjiao in their pursuit of carbon neutrality. In addition the source‐side price sensitivity analysis found that the hydrogen storage solution was cost‐competitive only when the capital costs on the storage and source sides were reduced by about 70%. However the hydro‐ gen storage system had the lowest carbon emissions about 14% lower than the battery ones. It was also found that power generation cost reduction had a more prominent effect on the whole system’s NPC and LCOE reduction. This suggests that policy support needs to continue to push for genera‐ tion‐side innovation and scaling up while research on different energy storage types should be en‐ couraged to serve the needs of different source–grid–load–storage systems.

Under the background of energy interconnection and low-carbon electricity integrated energy systems (IES) play an important role in energy conservation and emission reduction. To further promote the low-carbon transition of energy this paper proposes a distributed robust optimal control strategy for IESs based on energy trading. Firstly an IES model that includes an electric hydrogen module and gas hydrogen doping combined heat and power is established and ladder-type carbon trading is introduced to reduce carbon emissions. Secondly for the energy trading issues between photovoltaic (PV) prosumers and IES a bi-level model is constructed using Stackelberg game method where the IES acts as the leader and the PV prosumers as the followers. Noteworthy a distributed robust optimization method is used to address the uncertainty of renewable energy and load. Additionally the Nash bargaining method ensures an equitable balance of benefits among the various IESs and encourages them to participate in market transactions. On this basis an intermediary transaction mode is proposed to address cheating behaviors in trading. Finally the simulation results demonstrate that the proposed strategy not only effectively promotes cooperative operation among multiple IESs but also significantly reduces the system’s operating costs and carbon emissions.