Under the carbon peak goal and carbon neutral vision, offshore wind power has made great progress in China in recent years. The current development status and future planning of offshore wind power in China were analyzed, summarizing the installed capacity of offshore wind power, new models and adopted technical routes. The paper focused on the basic type, anti-corrosion technology, and operation and maintenance technology of offshore wind power. The floating offshore wind power was the focus of basic type research. The inspection and management systems for operation and maintenance were the primary focus of research in wind power operation and maintenance technology. By analyzing the development status of offshore wind power, the main technical routes and advanced achievements of each technology were identified. Finally, based on the current status and needs of domestic technology development, the future development trends of China's offshore wind power were prospected.

High temperature solid oxide electrolysis cell (SOEC) is a new type of high-efficiency electrochemical energy transfer device with high energy transfer efficiency, high reaction rate and wide application scenarios. It has enormous potential in the fields including production of low-cost green hydrogen and carbonaceous product with high added values. Nitrogen oxide treatment _{and ammonia synthesis may also be a promising direction of application. SOEC is expected to play an important role in the low-carbon transformation of energy, chemical industry, transportation and other fields. Based on the latest progress of SOEC in the fields of hydrogen production, oil production, nitride treatment and ammonia production, the development status of SOEC was systematically summarized, and the key directions for future development were prospected.}

The removal efficiency of ammonia in denitrification downstream equipment, concentration and distribution mechanism of ammonia in fly ash and slurry were studied under the condition of high concentration of ammonia escaping from denitrification by selective catalytic reduction (SCR) in coal-fired power plants. Through sampling analysis of 350 MW and 600 MW units, the results show that: the escaping ammonia removal efficiencies of air preheater, electrostatic precipitator and wet desulphurization system are 3.37%-6.63%, 75.14%-83.28% and 36.36%-46.38%, respectively. The ammonia removal efficiencies of these downstream environmental protection equipment are high, and the ammonia concentration at chimney entrance decreases obviously compared with that at denitrification outlet. The ammonia content in fly ash is inversely proportional to the particle size of fly ash. Ammonia concentration in desulfurized flue gas increases with the increase of ammonia concentration in original flue gas. The removal efficiency of ammonia in desulphurization system decreases with the increase of slurry pH value. The results have great significance to the units’ environmental protection and economic running.

Proton exchange membrane (PEM) water electrolysis is a green and sustainable method of hydrogen production. The development of efficient and economical electrocatalysts for anodic oxygen evolution reaction (OER) is the key to its large-scale commercialization. Iridium oxide catalysts supported by different manganese based oxide carriers (IrO _x /Mn₈O₁₀Cl₃, IrO _x /β-MnO₂ and IrO _x /α-MnO₂) were prepared by two-step synthesis method, and the content of iridium is about 55%. Compared with the commercial IrO₂ and other noble metal containing electrocatalysts, the synthesized catalysts have lower overpotential and higher current density. The overpotential of IrO _x /β-MnO₂ is only 228 mV at the current density of 10 mA/cm². The specific mass activity of IrO _x /Mn₈O₁₀Cl₃ reaches 916.7 A/g_Ir at 1.53V. The enhancement of OER activity is attributed to the abundant hydroxyl oxygen defects and Ir^III species on the catalyst surface. The rich crystalline-amorphous interface provides a large number of active sites for the reaction. The iridium oxide/manganese based oxide catalysts reported in this paper provide new insights for the development of efficient and economical catalysts for acidic OER.

The multi-energy complementary demonstra-tion projects of wind-solar-water-thermal-energy storage focuses on the development from the power side, and forms a complementary operation mode by using wind energy, solar energy, hydropower, coal to generate electricity. Multi-energy complementarity can effectively solve the problems of wind abandoning, light abandoning, water abandoning and power limiting, promote the absorption of renewable energy nearby, realize the stable delivery of electricity and improve the comprehensive utilization efficiency of energy. This paper summarized the connotation construction principles of multi-energy complementarity, detailed the development status and existing problems of the first batch of multi-energy complementarity demonstration projects, and analyzed in detail the development paths of different modes of multi-energy complementarity projects. This paper focused on the evaluation of wind and solar resources, new energy site planning, total installed capacity and optimal power ratio, optimal allocation of energy storage, coordinated control technology to ensure safety and stability and economic evaluation indicators of the project, so as to extract the general process and development mode suitable for the construction and promotion of multi-energy complementary projects. Finally, some summary and suggestions were put forward from the aspects of top-level design, market mechanism and operation management.

As a green and zero-carbon secondary energy, hydrogen is one of the key carriers for the development of energy transition and has become an important medium for energy interconnection. Hydrogen production by electrolytic decomposition of water is the main way to produce hydrogen in the future, which will promote the adjustment and transformation of energy structure. However, the development and industrial application of hydrogen energy technology in China is still at the initial stage. In addition, there are a lot of problems to be solved in the aspects of hydrogen energy production, storage and transportation, conversion and application industry chain. This paper analyzed the development status of green power hydrogen production technology, hydrogen storage and transportation technology, hydrogen application technology, and studied the typical scenarios of green electricity-hydrogen energy-multi-domain application and the key technologies of network coupling and integration. This work provides indicative ideas for the combination of hydrogen energy production, storage and application technology, and the development of application network in various areas.

Hydrogen energy has broad development prospects as a clean, carbon-free, flexible and efficient secondary energy and industrial raw material. Although the technologies of hydrogen production by water electrolysis, hydrogen storage and hydrogen supply have been relatively mature, the technology chain of hydrogen production-storage-supply is still in its infancy. It is of great importance to explore the technology chain in power system for the cooperative utilization of hydrogen energy and traditional electricity. This paper firstly introduced the basic principles, classifications, advantages and disadvantages of the technologies including hydrogen production by water electrolysis, hydrogen storage and hydrogen supply, and summarized the development of hydrogen production by water electrolysis, hydrogen storage and hydrogen supply technologies in the United States, Japan and the European Union. Then, the current status of above technologies in China was analyzed, and three possible application modes of hydrogen production by water electrolysis, hydrogen storage and hydrogen supply in power system in China were discussed. Finally, based on the current situation, the suggestions for promoting the development of hydrogen production by water electrolysis, hydrogen storage and hydrogen supply in power system in China were put forward, which provide a reference for optimizing the development of the whole technology chain of hydrogen energy production-storage-supply-use.

Hydrogen energy is an important part of China's new energy system,and its market scale and application scenarios are also expanding. Under the guidance of various national policies,provinces and cities have issued relevant policies in the fields of fuel cell vehicles and other fields according to their regional characteristics,which has accelerated the pace of hydrogen energy commercialization to a certain extent. In terms of fuel cells and other aspects,this paper sorted out the national and local hydrogen energy policies,and analyzed the application fields of hydrogen energy,the policy points of the future development planning of provinces and cities,and the profit model. Finally,the corresponding suggestions and prospects were given for the current process of hydrogen energy commercialization,which provide a reference for improving the efficiency of hydrogen energy in the future.

A model of hundred kilowatt proton exchange membrane fuel cell (PEMFC) combined heat and power system was established in Aspen Plus platform, which was composed of fuel processing unit, heat recovery unit and PEMFC unit. The key equipment model of fuel processing unit was built according to the reaction kinetic parameters, while PEMFC stack adopted the custom model from Aspen Custom Modeler. This paper verified the accuracy of key equipment model and analyzed the effects of operating parameters on system performances under steady-state conditions. The results show that under the operation mode of determining heat by power, the feed of combustion natural gas or the steam-carbon ratio of reforming gas can be appropriately reduced to improve electrical efficiency and exergy efficiency of the system. In addition, the linkage valve on the pipeline from pressure swing adsorption (PSA) to PEMFC can be adjusted to increase the anode inlet pressure of the stack, so as to improve the power generation. However, it is not recommended to increase the cathode inlet pressure of the stack, which will lead to raise of auxiliary equipment power consumption and decline in net power efficiency. When the power is determined by heat, the opposite adjustment method can be adopted, and the exhaust temperature of combustion flue gas and PEMFC tail gas can be reduced to improve the system thermal efficiency. The study results provide reference for adjusting the operation parameters of PEMFC combined heat and power system to achieve appropriate thermo-electric output ratio.

With a large number of distributed energy resources connected to the grid,virtual power plants as a distributed energy management technology have received a lot of attention because of their flexibility,efficiency and sustainability. This paper briefly discussed the background of virtual power plants, analyzed the hot directions and emerging directions in virtual power plants,and introduced the composition and structure of virtual power plants. According to the different goals and functions of virtual power plants,virtual power plants can be divided into mission-driven virtual power plants, economy-driven virtual power plants and hybrid driven virtual power plants. On this basis, the different operation modes and different solution methods of different types of virtual power plants were further discussed. Finally,the future development prospects of virtual power plants were prospected.

The development of industry has brought a large amount of CO₂ emissions. In the process of achieving the goal of carbon peak and carbon neutralization, carbon dioxide capture, utilization and storage (CCUS) technology is an indispensable key technology. The carbon capture method with high technology maturity at this stage and great development potential in the future is post combustion carbon capture technology, mainly including solvent absorption, adsorption, membrane method and cryogenic distillation. The development and industrial application of the four most commonly used carbon capture methods were briefly introduced, and the industrial applicability of several methods was analyzed, especially the chemical absorption method and physical adsorption method, which are most widely used in large-scale carbon capture projects currently running. Chemical absorption method, adsorption method and membrane carbon capture technology have great development potential in the future, which can quickly promote the achievement of the goal of double carbon and help the near-zero emission of carbon.

In order to cope with the increasing shortage of fossil fuels and a series of threats brought by global climate change, and achieve the goal of “dual carbon”, the proportion of renewable energy such as wind power and photovoltaic power in the grid has been continuously increased. However, the renewable energy power generation is random and uncontrollable, and the access location is scattered, which increases the difficulty of safe and stable operation of the power system. The introduction of virtual power plant (VPP)provides a feasible path for the above problems. The concept and classification of VPP was summarized and expounded. Moreover, the main differences between VPP and microgrid were compared. The existing researches from the perspectives of coordinated control, resource aggregation and optimal scheduling, and participation in the electricity market were analyzed and summarized. Taking the blockchain and digital twin technologies as examples, the applications of digital technologies in VPP were analyzed. Finally, the development prospects of VPP suitable for China’s national conditions and the challenges that may be faced in the future were pointed out.

The pollution-free characteristics of hydrogen energy make it a necessary means to achieve the goals of “carbon peaking” and “carbon neutralization” in China. With the implementation of a series of related policies, the development of hydrogen energy is to enter the fast lane. Large scale storage and transportation of hydrogen energy with low energy consumption is a technical bottleneck that needs to be solved urgently at present. Hydrogen liquefaction with mixed refrigerant is an effective means to solve this problem. This paper made a statistical analysis of the current hydrogen liquefaction with mixed refrigerants. The basic technical routes of different researchers and the current hydrogen liquefaction process were summarized. Furthermore, the suggestions for the development of hydrogen liquefaction process with mixed refrigerants were put forward, to provide effective support for large-scale storage and transportation technology of hydrogen and accelerate the realization of large-scale commercial use of hydrogen energy.

Hydrogen energy storage is an important support for promoting global green low-carbon transformation and realizing “carbon neutrality” goal. After the “double carbon” goal was put forward, hydrogen energy storage has become a hot topic of social concern. The safety of hydrogen energy storage is one of the problems that must be focused on and solved first. Safety problems in four stages of hydrogen production, hydrogen storage, hydrogen transport and hydrogen use were summarized and analyzed, including hydrogen leakage and diffusion, hydrogen combustion and explosion, compatibility of hydrogen with metals. At the same time, the current status and development of hydrogen leakage detection sensor technologies were analyzed, and the urgent problems and future development directions of hydrogen leakage detection technologies were pointed out.

Offshore wind power is a kind of green energy, which has attracted more and more attention. The anti-corrosion technology of offshore wind power facilities has become a current research hotspot. This paper first expounded the corrosion mechanism of equipments in the marine environment, and then introduced the commonly used anti-corrosion technologies for offshore wind power facilities, including the anti-corrosion coatings, cathodic protection, reserved corrosion allowance method, etc. Then, combined with an example, the anti-corrosion technology of thermal spraying and mineral grease coating in the new anticorrosion method in splash area were introduced emphatically. Finally, it briefly described the anti-corrosion detection and maintenance means of wind power facilities. It also introduced the corrosion protection methods used in Guishan wind power project in Zhuhai, Guangdong, which has been built into grid connected power generation in China, in order to provide some suggestions for improving the anti-corrosion level of offshore wind power.

The new energy is connected to the distribution network in the form of distributed generation, which brings uncontrollability, randomness and volatility to the system. With the help of modern power electronics, information and communication and automatic control technologies, the active distribution network with flexibility and controllability has become a development trend. The active distribution network planning is one of the major research fields in recent years. Based on the research results in this field at home and abroad, the research contents and methods of active distribution network planning were summarized, analyzed and prospected. The basic structure of the active distribution network was described, and the characteristics of the components of the distribution network were introduced. According to the different control variables, the planning models of active distribution network were classified, the optimization objectives in the model were summarized. The commonly used model solving algorithms and their advantages and disadvantages were analyzed and summarized. Through the discussion of key issues, the development trend of active distribution network in the future was analyzed.

Supercritical carbon dioxide(S-CO₂) Brayton cycle has great development potential in the field of efficient utilization of clean energy represented by fourth-generation nuclear energy and solar energy. A reasonable and reliable control strategy is the key to ensure the safe, stable, efficient and flexible operation of the S-CO₂ Brayton cycle system. This paper summarized the characteristics of S-CO₂ Brayton cycle control, and summarized and compared the S-CO₂ Brayton cycle control strategies under different application scenarios. The results show that the key control strategies of S-CO₂ Brayton cycle include running state control, impeller machine control, heat source control, etc. The variable load control strategies mainly include volume control, turbine bypass control, turbine inlet throttle control, compressor speed control, etc. The analysis results provide a reference for the selection of S-CO₂ Brayton cycle control strategies in related power generation fields.

With the massive access to renewable power generation and the advancement of the marketization process, the development prospects of virtual power plants that can give full play to the value of flexible resources have gradually emerged. In the process of virtual power plant participation in the market, the formulation of its market trading strategy needs to be challenged by the market mechanism. On the other hand, the market trading is closely related to the optimal scheduling of resources. The adjustable capacity of the internal resources, uncertainty, load behavior and other characteristics bring challenges to the development of trading strategy. This paper focused on the challenges and problems faced in the market transactions of virtual power plants, and summarized the market strategies adapted to the market mechanism. The key technologies required to deal with the formulation of the strategies, such as uncertainty handling, bid analysis methods, and virtual plant management methods were analyzed and reviewed, in order to provide a reference and a direction for the future research on virtual power plants.

Virtual power plant has become an important means to promote the construction of new power system and achieve the goal of “double carbon”. The intelligent operation management and control platform of virtual power plant effectively realizes the management and monitoring of flexible and adjustable resources in virtual power plant. The intelligent operation management and control platform of virtual power plant was described from the perspective of system framework and comprehensive functions. Firstly, the energy ecosystem of virtual power plant was analyzed and summarized based on framework of operation management and control, and market participation of virtual power plant. The intelligent operation management and control platform of virtual power plant was analyzed based on characteristics of platform system framework and platform structure framework. Then, the comprehensive functions of intelligent operation management and control platform of virtual power plant were analyzed from three aspects of functional structure blueprint, functional physical structure and functional scenario application.

The construction of anti-disaster backbone grid is of great significance to enhance the power supply capacity of power system under extreme natural disasters. Comprehensively considering economy and reliability, a planning method for anti-disaster backbone grid was proposed. The economy and reliability of the planning scheme were expressed as the strengthened cost and the benefit from loss reduction in life cycle. The objective function was to maximize the unit benefit from loss reduction of the original grid caused by the unit strengthened cost of backbone grid. Taking the network connectivity and safe operation of power system into account, a planning model for anti-disaster backbone grid was established. The model was solved by the improved crisscross optimization (ICSO) algorithm to find the optimal planning scheme. Finally, the effectiveness of the proposed method was verified by the simulation analysis of the IEEE 30-bus system.

Hydrogen fuel cells, as the energy supply device, have received a lot of attention because of their high energy density and low carbon emission characteristics. However, due to the insufficient hydrogen refueling infrastructures, the hydrogen cost is high, and the dynamic response of hydrogen fuel cells is poor. Therefore, the hybrid power system of rechargeable battery and hydrogen fuel cells is generally used to supply energy to vehicles such as unmanned aerial vehicles (UAV), cars, and others. The energy management strategy of hybrid power system has an impact on the parameters of system dynamic response, economy and battery life. So the selection and design of energy management strategy are crucial to hybrid power system. This paper introduced the working principle of hydrogen-electricity hybrid power system and its energy supply methods. Besides, the current status of application and research progress of different energy management strategies for various application scenarios were summarized according to different control objectives. Finally, this paper presented the challenges of hybrid energy management strategies and outlooks their future development direction.

Based on the demand of China to achieve carbon neutrality and zero carbon energy architecture by 2060, this paper studied the future energy system and the realistic path of energy transformation in China. Combined with the trend of energy technology development and the actual situation of China’s current energy system dominated by fossil energy, the hard constraints of China’s energy transformation were analyzed. By comparing and studying the feasibility, the main challenges of different technology options for carbon neutrality energy solutions, and the global energy development trend, this paper deduced the realistic path of realizing carbon neutrality energy architecture and zero carbon energy transformation in 2060 under the premise of ensuring national energy security. Finally, the key technologies and the policy measures were put forward, which should be promoted to build a novel energy system with renewable energy as the main body for the future.

Under the background of “dual carbon”, new energy sources have begun to be connected to the grid on a large scale. However, the randomness and volatility of new energy generation significantly impact the power grid, making it urgent to build a new power system. As the cornerstone of the power system, traditional thermal power will transform into a basic security and system regulatory power supply, providing reliable capacity, peak regulation and frequency modulation and other auxiliary services. The flexible transformation of thermal power units has become an inevitable choice. The phased objectives, difficulties, and challenges of building a new power system were analyzed, along with the problems encountered in the flexible transformation of thermal power units at the present stage. Combined with thermal power operation data, the technical ways of configuring energy storage equipment for thermal power units were analyzed. The research shows that there are several issues in building a new power system, such as power system instability, difficulties in transforming traditional thermal power, high energy consumption, and environmental pressures. The flexibility transformation of thermal power units faces challenges such as insufficient peak regulation capacity, high operation costs, slow load response, high operation energy consumption, safety concerns, etc. The integration of thermal power and energy storage will bring better economic and environmental benefits.

Under the carbon trading mechanism, virtual power plants (VPP) aggregating distributed energy resource (DER) to participate in electricity market (EM) trading will help new energy consumption and improve environmental benefits. This paper constructed a multi-agent VPP model including wind turbine, photovoltaic power, controllable distribution generation, stored energy, and flexible load, and formulated bidding strategies for each entity participating in the electric energy market (EEM) and peak regulating market (PRM). The EEM and PRM examples showed that participating in peak regulating bidding by VPP could achieve the maximum benefits of VPP and reasonable distribution of the interests among DER members. Moreover, this paper introduced the carbon trading mechanism, analyzed the correlation between changes in carbon trading price and wind and solar consumption rate, carbon emissions and VPP benefits, and further explored the impact of carbon sink resource trading on electricity price, output and energy demand change rate. It provided a basis for the ecological protection compensation mechanism of carbon sink value, and also provided a reference for the price transmission effect of carbon market (CM) on EM under the coordination of electricity-carbon market and the optimization design of CM price mechanism.

Virtual power plant (VPP) is a new type of operation mode. It can effectively aggregate a large number of demand side resources and formulate effective dynamic aggregate control strategies to achieve power complemen-tation in different time and space of the power grid and improve the flexibility of power grid control and the economy of the system. From the perspective of power grid dispatching, this paper analyzed the characteristics of typical power grid demand response behavior, and proposed the demand response capability indexes and the classification and aggregation method of VPP. Then, a multi-source VPP regulation model was constructed, and the results supported the hierarchical and regional complementary regulation of VPP response resources. Finally, taking a park as a case, the rationality of VPP control strategy and the scientificity of multi-source VPP control were analyzed. The results show that the overall dynamic control strategy can guide the VPP to give full play to the demand response value in a scientific and reasonable way, and promote the stable load of power grid and the safe and stable operation of the system.

Accurate power load forecasting is conducive to ensuring the safe and economic operation of the power system. Aiming at the problems of low prediction accuracy and long time consuming of the current prediction algorithms, an improved deep learning (DL) short-term load forecasting model based on random forest (RF) algorithm and rough set theory (RST), namely RF-DL-RST, was proposed. Firstly, based on historical data, the model used RF algorithm to extract the key features that affected the load forecasting. Then, the key features and historical load data were trained as the input and output items of deep neural network (DNN), and the prediction results were corrected by RST. After that, the rough set method was used to revise the prediction results. Finally, the simulation was verified by an example. The results show that the prediction accuracy of the model is higher than that of a single DNN model and a model without RST revised.

Objectives Under the background of the “double-carbon” target, thermal power is facing great pressure to reduce emissions. Thermal power carbon footprint evaluation can directly show the greenhouse gas emissions of thermal power and help tap the potential of carbon reduction. Therefore, the research status of thermal power carbon footprint assessment was reviewed. Methods This paper introduced the main standards and methods for thermal power footprint evaluation, and summarized the thermal power footprint evaluation process. The differences in the evaluation process were reviewed and some suggestions were given. The life cycle is divided into upstream, core and downstream. According to the high concentration of carbon emissions in the core links, the carbon footprint of the construction, decommissioning and power transmission of coal-fired power plants can be ignored in some cases. Conclusions The life cycle of different types of thermal power generation is similar, but the carbon footprint of waste incineration power generation does not include the acquisition process of domestic waste. Regardless of the form of thermal power, in the absence of measured emission factors, it is recommended that the emission factors select the default values of the published standards, literature and databases at home and abroad.

In order to promote the utilization of clean and renewable energy such as solar energy and hydrogen energy, and better integrate it with virtual power plant technology, aiming at the coupling system of photovoltaic power station and electrolytic water hydrogen production, the operation mode of large-scale aggregate resources was constructed and the relevant economic analysis considering the initial investment of resources was carried out. At the same time, combined with the analysis of the annual output data of the actual photovoltaic power station project, it was discussed that when this kind of coupling resources were used as virtual power plant resources, while supporting the new power system and promoting the consumption of new energy, it could maintain and continuously optimize its own economy. The operation mode optimization elements, equipment function characteristics and market conditions worthy of attention were pointed out, which provided a reference for related research.

China’s equipment manufacturing system and Europe’s experience in project complement each other. Firstly, this paper focused on the industrial chain and key technologies of floating offshore such as wind turbines, floating foundations, mooring and anchoring system, dynamic submarine cables, survey and design, construction, transportation and installation, operation and maintenance, etc. An evaluation system for the industrial chain with deep vertical analysis and horizontal expansion and comparison was established. Then, combined with the results of China-Europe comparison in different segments, 18 key cooperation areas were proposed. Finally, the study also explored the 4 stages of cooperation paths: exchange & sharing, cooperative construction, scale application and global promotion. It is expected to solve the problems of sole form of demonstration prototype foundation, high cost and immature industry chain,and provide certain ideas and inspiration between China and Europe floating offshore wind power cooperation.

With the increase of new energy penetration, the power balance and frequency stability problems brought by its randomness, intermittency and volatility has become increasingly serious. It is difficult to cope with these problems only by traditional centralized power plants. Flexible resources in the power systems should also bear a part of the responsibility for the balance of power and energy. Virtual power plant (VPP) can aggregate a large number of distributed flexible resources with different characteristics, participate in the electricity markets as a whole and accept the dispatch of the grid, and provide important support for the real-time power balance of the power systems. The development of VPPs should be based on a large number of flexible resources, advanced communication and dispatching/control technologies, and efficient business models and good market policies. The operation of VPPs can be attributed to the energy flow of the energy network, the information interaction of the information network and the value transfer of the value network. Therefore, based on the three-layer network architeciture of “energy-information-value”, the operation modes and control schemes of different types of VPPs were analyzed, and the idea of “three flow separation-convergence” for VPP architecture design was proposed. The findings provide useful guidance for the design, construction and operation of VPPs.

With the development and evolution of the information revolution, promoting the integration of a new generation of digital technology with traditional power generation system, and promoting the digital construction of power generation systems is an important way to support energy transformation and digital grid construction. Based on the digital business needs of power generation system, this paper summarized the business needs of data in various scenarios such as the full life cycle management, intelligent operation and maintenance, and intelligent operation. The architecture of power generation system was expounded from the aspects of network structure and digital technology architecture. The key technologies and applications in the process of digitalization of power generation system were sorted out. Finally, the problems that need to be solved in the process of digitalization of power generation system were discussed.

With the advancement of the national goal of “double carbon”, the hydrogen production by electrolytic water will usher in explosive growth, among which the topology and control of power supply is of great significance to improve the efficiency of hydrogen production system. This paper took the topology of isolated DC/DC hydrogen production power supply as the main line to sort out and analyze, and summarized and analyzed the structures, advantages and disadvantages of single-stage, two-stage, parallel and multi-port DC/DC isolated hydrogen production power supply according to different application scenarios. The analysis shows that the full-bridge resonant converter and the control scheme considering the temperature, pressure and hydrogen/oxygen cross-osmosis feedback of the electrolytic cell will become the development trend of high-power large-scale hydrogen production power supply which can adapt to wide range and strong fluctuation. Moreover, the isolated three-port DC/DC conversion power supply will become the distributed integrated electric-hydrogen coupling development mode in the future. The research of this paper aims to provide theoretical reference for the further research of hydrogen production by electrolytic water.

Focusing on the goal of carbon peak and carbon neutrality, the low-carbonization of the whole link of energy power system (i.e., source-network-load-storage) faces new requirements and challenges. The high proportion of renewable energy generation has become an inevitable trend. Considering the impact of the uncertainty of renewable energy generation on the safe and stable operation of the power system, the use of virtual power plant (VPP) with multi-energy complementary characteristics is a favourable way to solve this problem. Therefore, an optimal scheduling strategy of multi-energy complementary VPP was proposed. Firstly, taking into account the coupling relationship between multiple energy sources, a VPP operation mechanism that takes into account the entire source-grid-load-storage chain was constructed. Secondly, according to the proposed operation mechanism, a multi-energy complementary optimal dispatching model with low carbon economy as the goal was proposed to promote the consumption of renewable energy by coordinating the dispatching of various types of devices. Finally, the effectiveness of the proposed strategy was verified by simulating and analyzing a reference case of a multi-energy complementary VPP including renewable energy generation in a region.

Under the background of energy complementarity and low-carbon economy, virtual power plant (VPP) is an effective carrier for achieving optimal allocation of regional resources and new energy consumption. At the technical level,the CO₂ recycling through carbon capture power plant (CCPP) and power-to-gas (P2G) conversion devices was realized, a CCPP-P2G coupling model was established, and a price based demand response model considering user satisfaction on the load side was introduced. In terms of low-carbon policy, the ladder carbon trading mechanism was introduced into VPP to constrain carbon emissions. Then, with the goal of minimizing the total cost, a low-carbon economic dispatch model for VPP was established. By setting different scheduling scenarios for comparison, the effectiveness of the model in low-carbon economy operation of VPP was verified, and the impact of carbon trading parameters on the carbon emissions and costs of VPP was explored through sensitivity analysis. The results show that the model has guiding significance for VPP low-carbon economic scheduling.

With the gradual increase in the proportion of new energy, energy storage technology, as an auxiliary new energy grid, has attracted wide attention. Hydrogen energy storage and fuel cell technology have been listed as strategic energy technologies in China, and have been actively applied in the market and enterprise development. Hydrogen production from electrolytic water can stabilize the fluctuation caused by the connection of renewable energy to the grid and help the power grid to cut peak and frequency modulation. As a power generation device to improve energy conversion rate, fuel cell has the advantages of low noise and no pollution, it is one of the effective ways to absorb renewable energy. This paper made a comparative analysis of the development status and advantages of the existing energy storage technologies, the key technologies and research directions of hydrogen energy storage system were introduced emphatically, and the commercial development of hydrogen energy storage was prospected.

Aiming at the influence of inductance on DC/DC conversion performance, this paper took the Boost converter as an example to analyze the factors affecting the equivalent circuit and conversion efficiency of Boost converter under the non-ideal conditions, and obtained the relationship between inductance parameters and circuit output voltage and conversion efficiency. On the basis of analyzing the influence of inductance parameters on the current ripple and circuit efficiency, a method to limit the selection range of inductance value was proposed based on the traditional design of filter inductor considering the critical continuous current. The local hysteresis loss and copper loss of KS226-075A core were calculated, and the change trend of DC/DC converter conversion efficiency with the increase of inductance was obtained. Finally, the correctness of the theory and the feasibility of the method were verified by experiments. At the same time, the selection range of inductance was corrected according to the experimental results, and the error between the calculation and experimental results was analyzed and explained.

Objectives As an important support for the new power system, hydrogen gas turbines can help reduce carbon emissions and are conducive to grid peak regulation. They are the focus of technological innovation in the global future strategic emerging industries. Many key issues faced by hydrogen blending gas turbine power generation technology from demonstration to commercialization, need to be solved. Methods H-class gas turbines were taken as the research object, and the strategic planning and demonstration projects of hydrogen blending gas turbine power generation in China and abroad were introduced, and the technology routes of H-class gas turbines of major gas turbine manufacturers were compared. The analysis and suggestion was made from four aspects for the scale application of future hydrogen blending gas turbine power generation technology, including hydrogen source, system transformation, emission impact and hydrogen blending power generation cost. Results Renewable energy electrolysis of water to produce hydrogen will be the main source of hydrogen blending gas turbine power generation. In addition, the development of new dry low nitrogen oxide burners, which are suitable for unstable combustion of hydrogen blending, will be the key direction for future hydrogen blending gas turbine system transformation. The higher the hydrogen volume percentage is, the greater the CO₂ emission reduction is. However, the NO _x emission is on an upward trend. Moreover, there is a risk of exceeding the standard value, and the future cost of hydrogen blending gas turbine power generation can reach the same level as the cost of natural gas power generation. Conclusions With the reduction of the cost of large-scale renewable energy hydrogen production, and the implementation of carbon tax and the maturity of hydrogen blending power generation technology, the gas turbine hydrogen blending power generation will gradually enter large-scale application.

Objectives Magnetic confinement fusion is regarded as a critical solution to future global energy challenges. As the central component of magnetic confinement fusion devices, magnets play a crucial role in generating and sustaining plasma stability. A review of the magnetic system structures and specifications in representative magnetic confinement fusion devices worldwide was provided. Methods The technological evolution of fusion magnets was reviewed, from copper-based to low-temperature superconducting, and finally to high-temperature superconducting magnets. The structure and performance parameters of magnetic systems in various typical fusion devices were summarized systematically. Additionally, the technical challenges in magnet development were explored and an outlook on future development trend was offered. Conclusions Advances in magnet technology are vital for enhancing the performance of fusion devices and accelerating the commercialization of fusion energy. With the increasing application of high-temperature superconducting materials and continuous optimization of magnet designs, the practical realization of fusion energy is becoming increasingly feasible.

CO₂ is the main greenhouse gas. The reduction of CO₂ emissions to cope with climate change has become an international consensus. Industrial flue gas is considered to be an important source of CO₂ emissions. The characteristics of industrial flue gas CO₂ emission, the main test and treatment technology were studied and analyzed. The CO₂ concentrations in power plant, steel and cement flue gas are 9.7%-15%, 2%-28% and 11%-29%, respectively. CO₂ testing methods mainly include non-dispersive infrared absorption, gas chromatography, spectroscopy, and chemical absorption, etc. Among these, the non-dispersive infrared absorption method is the most mature in application and is the mainstream technology for fixed source CO₂ testing at present. CO₂ capture technologies mainly include absorption, adsorption, membrane separation, and cryogenic methods. Among these, the chemical absorption method is widely used for capturing low concentration CO₂ (volume concentration ≤30%). The purpose of this study is to provide reference for the subsequent large-scale industrial carbon reduction.

Objectives Liquid storage and transportation is one of the effective ways to realize large-scale and long-distance storage and transportation of hydrogen and ensure the large-scale application of hydrogen energy. At present, there is relatively little research on the preparation, storage, transportation, and refueling of liquid hydrogen in China. Therefore, the current development status analysis of key technologies in these fields was conducted. Methods The advantages and disadvantages of high pressure gaseous storage, liquid hydrogen storage and solid hydrogen storage technologies were compared. The main liquefaction methods, liquid hydrogen storage insulation technologies and key materials in the process of liquid hydrogen preparation were reviewed. The characteristics of different transportation modes and equipments of liquid hydrogen were analyzed. The construction of liquid hydrogen hydrogenation station was combed, and the liquid hydrogen filling technologies were compared. The main application fields and industrialization modes of liquid hydrogen were expounded, and a statistical analysis of the patent technologies of liquid hydrogen storage and transportation in China in recent years was carried. Results The “neck-stuck” difficulties faced by the development of liquid hydrogen storage and transportation in China and the urgent need for technical research directions were proposed. Conclusions The results can provide reference for the key technology research and equipment development of liquid hydrogen.