Three tower heliostat field layouts, EB, No blocking-dense, and DELSOL derived from the radial staggered layout and the principle of no blocking loss, were studied. After summarizing the mathematical models of the three heliostat field layouts, combined with some design parameters of Gemasolar power tower plant, the software SolarPILOT was used to model and simulate the heliostat field according to the three layout modes. MATLAB was used to process the coordinate data of the heliostat field obtained by the modeling, and the change curves of radial spacing and azimuth spacing were obtained, so as to verify the rationality of the three layout mathematical models. The layout rules of the heliostat ring were obtained by analyzing the arrangement characteristics of the basic ring and the staggered ring in each heliostat field. At the same time, the performance of different layouts was compared from the number of heliostats, the optical efficiency, the land utilization ratio and the receiving energy of the heliostat field, and their advantages and disadvantages were analyzed. The results show that in the range of 1 000 m radius of the heliostat field, the average annual optical efficiency and land utilization rate of the heliostat field under the No blocking-dense layout are the highest, followed by the EB layout. However, the number of the heliostats and the receiving energy of the heliostat field under the EB layout are the largest, and the performance characteristics of the DELSOL layout are the lowest.

Metaverse is a new internet application and social form of virtual reality integration which is produced by integrating a variety of new technologies. With the goal of “carbon peak and carbon neutrality” and the proposal of new power system, the construction of power system in metaverse is the trend in the future. Considering the application of metaverse applications in power systems, this paper used digital twin technology and internet-of-things technology to understand the metaverse, and then analyzed the power systems in the metaverse. Different from the current virtual reality, the metaverse has four characteristics: virtual fusion, diversification, immersion, economic system and civilization. Focusing on the above two means and four characteristics, this paper introduced the metaverse from the perspective of science and engineering, and expounded the framework and functions of power systems. Finally, this paper discussed the potential applications and prospects of metaverse in power systems.

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.

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.}

Proton exchange membrane fuel cells take advantages of high efficiency, no pollution and good fuel adaptability. The green energy network formed by combining fuel cells with reliable hydrogen production is an effective way to achieve carbon neutrality. It is expected to promote the technological research and upgrading of new energy vehicles, unmanned air vehicles, ships and other industries those use fuel cells as electricity and thermal power source. However, a safe and stable hydrogen supply technology is a major bottleneck limiting the development of fuel cell power generation applications in mobile scenarios. Hydrogen production by in-situ methanol reforming is hopeful to make a breakthrough in mobile hydrogen source technology based on fuel cell. In this paper, the research progress of methanol reforming hydrogen production, the research progress of reactors for methanol reforming hydrogen production and the application of methanol reforming fuel cell power generation system were reviewed to provide reference and guidance for promoting the commercial development and application of methanol reforming fuel cell in the field of new energy.

Solar photovoltaic/thermal (PV/T) technology is the integration of PV modules and solar collectors, which can simultaneously generate electricity and provide thermal energy. The overall efficiency and the space utilization efficiency will be improved simultaneously by the combination of two modules. The types of PV/T technology and related theoretical researches were summarized firstly in this review. By focusing on the heat loss and overtemperature problem of flat-panel PV/T technology, the design progress has been reviewed and analyzed. The state-of-art study on integration of phase change materials with PV/T (PV/T-PCM) technology was comprehensively summarized. The deficiencies in the research and the future development tendency were also prospected in order to provide theoretical guidance for further development of PV/T systems.

Accurate estimation of state of charge (SOC), battery state of health (SOH) and prediction of battery remaining useful life (RUL) of lithium-ion battery are important contents of battery management. It is of great significance to prolong battery life and ensure the reliability of battery system. Researchers all over the world have done a lot of research on battery state evaluation and RUL prediction methods, and proposed a variety of methods. This paper first introduced the definition of SOC and SOH and the existing estimation methods and compared them. Then, the definition of RUL was introduced and the main methods were classified and compared. Finally, the challenges of lithium-ion battery state estimation and RUL prediction were summarized, and the future development direction was proposed.

In the past three decades, China’s power industry has developed rapidly and solved the problem of efficiency and cleanliness to a certain extent. However, the implementation of the “double carbon” target has put forward the requirements of low carbon development for China’s power industry. Improving energy utilization efficiency, increasing the proportion of zero-carbon energy and carbon-neutral energy, and equipping carbon capture, utilization and storage (CCUS) technology are three important ways to achieve carbon emission reduction in the power industry. Based on the carbon neutral formula of power system, the carbon emission reduction history of China’s power industry and the carbon emission reduction contribution of different pathways between 2000 and 2020 were analyzed, and the current situation and routes of CCUS technology development in China were described. The results show that between 2000 and 2011, improving the efficiency of carbon-containing energy utilization made the main contribution to carbon emission reduction in the power industry, and after 2011, the increase of the proportion of zero-carbon energy contributed more to carbon emission reduction in the power industry. To achieve the goal of carbon neutrality in the power industry, CCUS technology is indispensable when the fossil energy cannot be completely replaced. Currently, the high cost and energy consumption of CCUS technology are the main reasons that hinder its promotion. The fuel source capture technology realizes the graded utilization of energy and the enrichment of carbon components, which reduces the energy consumption of CO₂ capture, and the efficiency of fuel source carbon capture system can generally be improved by 5 to 8 percentage points compared with the current mainstream carbon capture technology.

In view of the unstable performance of the cold-end system of traditional power plants and the high annual operating cost, a mathematical model based on the heat, resistance, civil construction and annual operating cost calculation of the direct flow cold end system based on negative digging depth was established, and the cold end system configuration was obtained from different conditions outside the tower. The optimal configuration was used to analyze the effect of cooling water for intlet tower water temperature, coagulator area unit price and condenser negative digging depth on the performance of cold end system. The results show that reducing the cooling water for intlet tower water temperature and condenser area unit price can reduce the annual operating cost of cold end system. The performance parameters of the cold end system with a negative digging depth of 3 to 5 m reach the lager value. Therefore, selecting the cold end system configuration according to different weather parameters outside the tower can improve the operating efficiency of the power plant and reduce the annual operating cost of the cold end system.

As an important part of carbon capture, utilization and storage(CCUS) technology, CO₂ sequestration in saline aquifers is an effective means to achieve the goal of carbon neutralization. Improving the research scheme of CO₂ sequestration mechanism in saline aquifers is of great significance to accurately evaluate the storage potential. The storage mechanism of CO₂ sequestration in saline aquifers was discussed, the commonly used characterization techniques were summarized, the effects of different parameters on sequestration in saline aquifers were discussed, and the future development of this technology was prospected. According to the study of different storage mechanisms, the characterization technology of sequestration in saline aquifers mainly includes reservoir rock characterization, core flooding experiment, solubility experiment, mineralization reaction experiment and so on. The storage potential of CO₂ sequestration in saline aquifers is affected by many parameters, such as the residual water saturation, residual gas saturation, solubility and salt precipitation. Therefore, it is very important to select appropriate characterization techniques to determine the relevant parameters to ensure the accuracy of storage potential evaluation. In addition, the analysis of the whole process storage mechanism and the research of marine CO₂ sequestration in saline aquifers project are the important research direction of this technology in the future.

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 new power system with high proportion of new energy and power electronic equipment is an important means to achieve the goal of “double carbon”, but the new power system will also bring a series of unstable problems. In the new power system, grid-forming control technology (GFM) has the characteristics of voltage support and active inertia, which can replace synchronous machine to realize grid support and maintain power system stability. Therefore, GFM has a broad development and application prospect. Based on this, this paper first briefly introduced the topology of energy storage converter, and selected its type according to the control characteristics of GFM technology. After that, a reasonable summary and analysis of the existing control strategies of GFM was made, the current research difficulties, problems and challenges in the development process and the research prospects were put forward, and the ideas for the construction of grid-forming construction were provided.

This paper reviewed the current development research of China’s offshore wind power industry in the field of integrated design of wind turbine, tower and foundation. This paper explored the feasibility of integrated design from the aspects of load reduction optimization technology, structural optimization technology and engineering exploration and application, and discussed the key technologies and implementation methods of integrated design that can be adopted under the optimization goal of lightweight offshore wind turbine support structure. The research shows that China’s offshore wind power industry needs to be gradually implemented from three levels: providing the prerequisites for integrated design, using the technologies that can be adopted at the current stage,and exploring the next research directions. In the context of offshore wind power moving towards grid parity, owner-engineers and third-party certification bodies need to play a greater role in promoting the integrated design method.

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.

1 000 MW coal-fired unit, as one of the best domestic advanced units, the performance evaluation and analysis of the key parameters of its denitrification unit after the ultra-low emission reformation can provide reference and guidance for stable and safe operation of selective catalytic reduction (SCR) flue gas denitrification unit under ultra-low emission of coal-fired units. Taking the SCR denitrification unit of a 1 000 MW coal-fired unit that had achieved ultra-low denitrification emission as an example, the key operating parameters of the SCR denitrification unit were studied, such as denitrification efficiency, NO _x concentration distribution at the inlet and outlet, ammonia escape, etc., the main performance of the denitrification unit was analyzed. The test results show that the overall performance of the SCR denitrification unit is good after the ultra-low emission transformation, but the problems of poor flow field uniformity and excessive ammonia escape still exist. Therefore, the adjustment of low nitrogen combustion, the optimization of ammonia injection, the uniformity test of flow field and the life-cycle management of catalyst should be strengthened.

The power balance of the new power system mainly based on new energy is facing an important technical challenge, and the participation of flexible load in power system regulation is an important way to enhance the active balance capability of the new power system. In view of the obvious seasonal and temporal characteristics of the electric and thermal loads, the new energy sources are “extremely cold and hot without wind” and “late peak without light”, and the thermoelectric loads in the new power system show the trend of anti-peak regulation. To address this problem, this paper analyzed the spatial and temporal characteristics and energy-use characteristics of electric and thermal loads, explored their regulation potential, focused on the control scenarios of electric and thermal controllable loads, and systematically gave a flexible scheduling strategy for electric and thermal loads to complete the flexible control and regulation of electric and thermal loads. The results realize the network-load cooperative optimization and flexible scheduling on the whole time scale, and thus verify the feasibility of the real-time participation of telectric and thermal loads in the scheduling of the grid.

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.

The impact of climate change on human society has attracted more and more attention, and the risk of power outage caused by a series of extreme weather is becoming more and more significant. In order to deal with climate change, especially extreme weather, human society needs to adopt two coping strategies of mitigation and adaptation. For the developing countries and small island countries, since climate change has already taken place, the climate problem will first be adaptation. In order to solve the problem of how the power system can fully adapt to climate change from all aspects, a power system development system adapted to climate change was established, and a construction method of power system development path covering extreme meteorological factors was proposed. On the basis of summarizing the impacts of various extreme weather on the power system, the vulnerability of power grid was evaluated. The overall strategy of adapting to extreme weather was studied, and the scheme of power system adapting to extreme weather events was proposed, namely planning-construction-emergency management-assessment (PCEA) disaster resistance system. In the planning stage, the study focused on the minimum power grid planning and built the minimum power grid backbone network without power outage. Based on the application examples in different stages of the scheme, it was verified that the PCEA system can make the power system better adapt to the extreme weather.

In order to fully characterize the emission reduction performance of SO₃ by low-low temperature electrostatic precipitator system (FGC+ESP), a method to test low-concentration SO₃ was proposed, namely “two-stage controlled condensation + one-stage isopropanol absorption” sampling method, which can improve the accuracy of its test data. According to this method, in the pilot test, the SO₃ removal efficiency of the low-low temperature electrostatic precipitator (LL-ESP) system (90 ℃ at ESP entrance) was 96.15%. In four groups of field measured data from three engineering projects, the SO₃ removal efficiency of LL-ESP system was 69.1%-96.6%. The mechanism of SO₃ adsorption and agglomeration by fly ash particles under low-low temperature conditions was verified. The study results can provide reference for the large-scale promotion and application of LL-ESP technology and SO₃ emission reduction of coal-fired power plants.

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.

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.

In order to establish a typical terminal multi-energy complementary system and know the characteristics of different optimal configurations and influence factors of its performance under different optimization objectives, this paper proposed a terminal multi-energy complementary system that integrates solar energy, wind energy and natural gas. The energy flow characteristics were analyzed based on the bus-bar structure, and an integrated optimization model for the design and operation of the system was established accordingly. Furthermore, the effects of optimization objectives and energy prices on the optimal configuration and performance of the system were studied, and the applicable scenarios of typical equipment such as micro-gas turbine, internal combustion engine and absorption chiller were illustrated, as well as the promoting effects of flexible power supply and energy storage device on the consumption of photovoltaic and wind power. The relationship between annual CO₂ emission reduction ratio and fossil fuel saving ratio of the system is consistent, and that between annual cost saving ratio and CO₂ emission reduction ratio is contrary under current technical and economic conditions. The most suitable natural gas price to ensure the applicable downward pressure exists and the effect of peak-valley difference of electricity price on system performance is clarified. The results can provide reference for system integration optimization design and energy price policy formulation.

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.

Perovskite solar cells (PSCs) have attracted extensive attentions due to their high-efficiency, simple preparation process and low-cost. The efficiency of the PSCs has increased from 3.8% to 25.7%. So far, more and more studies focus on n-i-p structured PSCs using SnO₂ as electron transport layer. However, its process reproducibility is relatively poor, and efficiency is still low. This report conducted a systematic study of planar n-i-p PSCs, mainly including the selection of transparent conductive oxide (TCO) glass, optimization of preparation parameters and the influence of storage conditions on device performance. Experimental results show that these parameters have an important impact on the device performance. At the same time, it was analyzed by scanning electron microscope, X-ray diffraction, absorption spectrum. The devices achieved an average efficiency of 21.85% and a highest efficiency of 23.47% with good reproducibility under the optimal conditions (Indium Tin oxide substrate, PbI₂ annealed at 70 ℃ for 1 min, standing time after dropping amine salt solution is less than 5 s, and stored in 4.5% humidity environment). This work provides scientific support for the preparation of high-efficiency and repeatable PSCs.

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 is a secondary clean energy which can be stored, moved and controlled. It is an ideal power energy carrier. The development and utilization of hydrogen as an energy source is an important means to tackle the climate change, ensure the national energy security and realize low-carbon transformation of the whole society. As an important greenhouse gas emission industry, the power industry, especially the power generation industry, should develop new energy applications including hydrogen as soon as possible to achieve zero-carbon energy transformation in the industry. According to the requirements of the “double carbon” goal, this paper analyzed the current situation of hydrogen application in China’s power industry, and put forward the main problems existing in the current hydrogen application. Based on the experience of power application development in major international hydrogen countries, combined the requirements of “re-electrification”, this paper put forward suggestions for the development of hydrogen power application from the perspectives of regulation formulation, policy support, financial innovation, and power industry scenario application. That is, during the “14th Five-Year Plan” period, it is necessary to make good technical reserves for hydrogen development, seize the opportunities for industrial development, and actively promote the transformation and upgrading of power system energy.

Anomaly detection of gas turbine hot components can ensure its operational safety and reliability. With the boom of artificial intelligence, data-driven fault diagnosis is becoming increasingly popular. However, in actual applications, fault data of gas turbines are rare or even unavailable. Aiming to solve the anomaly detection problem of gas turbine hot components in the case of only normal data available, this paper proposed an anomaly detection method based on the fusion of deep autoencoder and support vector data description. This method uses normal data to train deep autoencoder and then uses the reconstruction errors of deep autoencoder to train support vector data description. Experiments show that, compared with conventional anomaly detection methods, the proposed method can significantly improve the anomaly detection accuracy and realize more sensitive and robust anomaly detection of gas turbine hot components.

As a new type of energy storage device, lithium ion capacitors not only have high energy density, but also have excellent power density and long cycle life. They have great application potential in high-power and long-life application scenarios. Firstly, this paper theoretically analyzed the reasons for the energy limitation of electrical double-layer capacitors and the performance improvement of lithium ion capacitors, and then compared and discussed the performance differences between lithium ion capacitors and electrical double-layer capacitors. Finally, the application potential of lithium ion capacitors in intelligent instruments, automotive energy conservation and emission reduction, new energy vehicles and renewable energy power generation and power storage was briefly analyzed. The results provide a theoretical basis for further improving the energy density of lithium ion capacitors, and point out the direction for the application of lithium ion capacitors.

The wide application of wet desulfurization technology makes the desulfurization efficiency reach more than 90%, but the high moisture content of flue gas after desulfurization increases the possibility of smog formation. The spray tower was the main body of research, and the three-dimensional steady-state numerical simulation of gas-liquid two-phase flow field in the tower was carried out based on Fluent software. The results show that the spray droplet diameter plays a key role in flue gas condensation and dehumidification. The smaller the droplet diameter, the larger the gas-liquid two-phase contact area, the more obvious the heat transfer effect. If the droplet diameter is less than 700 μm, the flue gas temperature drop above 6 K can be achieved. When the inlet flue gas temperature is in the range of 319-335 K, the ratio of condensed water caused by this temperature is basically unchanged. The spray droplet velocity has an integration effect on the flue gas flow field. Choosing the appropriate droplet velocity can reduce the flue gas reflux area, and improve the space utilization rate in the tower. When the droplet velocity increases to 40 m/s, the temperature drop of outlet flue gas can increase by about 1.9 K.

Aiming at the problems of difficult manual selection of features, cumbersome classification steps and low accuracy in traditional power quality disturbance classification methods, a disturbance classification method based on particle swarm optimization (PSO) and convolutional neural network (CNN) was proposed. Firstly, the one-dimensional time series of power quality disturbance signals were converted into two-dimensional matrices with equal rows and columns by using the reshaping function, and these two-dimensional matrices were properly divided into training data set and test data set. Secondly, the classification model of power quality disturbance was built based on CNN. Thirdly, the PSO algorithm was used to optimize the parameters of the classification model, and the trained data set was used to train the optimized power quality disturbance classification model. Finally, the trained power quality disturbance classification model was tested by using the test data set, and the class results of various power quality disturbances were obtained according to the output labels. Simulation results show that the classification model can extract the characteristics of power quality disturbance data by itself. Compared with other power quality disturbance classification models, this method has higher classification accuracy for power quality disturbance signals.

Wet electrostatic precipitator (WESP) is a fine treatment equipment for the treatment of coal flue gas. Taking a 660 MW ultra-low emission unit as the research object, the multi-pollutant removal performance and energy efficiency parameters of WESP were tested and analyzed systematically. The removal efficiencies of particulate matter, fog drop, SO₃ and Hg of WESP were 81.12%, 75.60%, 76.13% and 53.08%, respectively, and the power consumption was 402.6 (kW·h)/h, which met the design requirements. The emission mass concentration of each pollutant were 4.20, 17.25, 9.80, 4.08×10^-4 mg/m³, respectively, the emission factors were 13.76, 56.49, 32.10, 1.34×10^-3 g/(kW·h),respectively, the specific power consumption was 1.48×10^-4 (kW·h)/m³.The energy consumption for particle removal per unit mass was 22.87 (kW·h)/kg, which was in the industry average level. This study can provide reference for the subsequent pollutant reduction and energy efficiency control of coal-fired power plants.

Natural gas combined cycle (NGCC) has the characteristics of clean, high efficiency and strong variable load capacity under certain load range. The integration of NGCC unit with carbon capture system is an important way to achieve carbon emission reduction. A 884 MW natural gas combined cycle which consists of two gas turbines, each of which is equipped with a heat recovery steam generator in International Energy Agency (IEA) report was taken as the reference system, and the system was modeled and verified by Ebsilon software. Based on the principle of energy cascade utilization, the following four different integration schemes of NGCC unit with carbon capture system were proposed. Steam extraction from the IP/LP crossover and the condensate is returned to the deaerator, steam extraction from the IP/LP crossover and the condensate after heat exchange is returned to the deaerator, steam extraction from the IP/LP crossover and the condensate is returned to the condenser, steam extraction from the IP/LP crossover and addition of a new turbine while the condensate after heat exchange is returned to the deaerator. The thermodynamic performance of four different integration schemes is further analyzed, and the energy penalty is 6.67%, 6.59%, 6.81% and 5.46%, respectively. It can be seen that the proposed scheme 4 can effectively reduce the energy penalty.

Offshore wind power is an important development trend in the field of renewable energy in China in the future. Firstly, this paper summarized the current development of domestic offshore wind power industry, analyzed the development trend of domestic offshore wind power industry chain, and then introduced the current cutting-edge technology of offshore wind power industry from the subdivided technical field. It mainly covers unit technology, including blade design and pitch control, transmission chain, motor, converter, main control system, etc; networking transmission technology, including AC, DC and low-frequency transmission technology, as well as compact and lightweight offshore platform design technology; engineering construction technology, mainly including offshore engineering, wind farm construction and submarine cable technology; offshore wind power operation and maintenance technologies, mainly including offshore wind power prediction, wake prediction, optimal dispatching, monitoring and maintenance, etc. The research results can provide the reference for the development of offshore wind power in China.

Metaverse is a new stage of digital revolution,which transforms the universe to highly interactive and hyper-spatiotemporal eco-system supported by multiple technologies. The application of metaverse in the power system can further improve the informatization and intellectualization of the system,becoming the next generation smart grid. This paper proposed a new concept of meta-power to represent the power system introducing the metaverse. Multiple technologies of the meta-power can enhance the flexibility,security,and intelligence of the power system operation. High interactivity of the meta-power can enable the convenient and immersed power system monitoring and maintenance. Hyper-spatiotemporal feature of the meta-power can tackle the spatial and temporal constraints of the power system operation,and facilitate the evaluation and deduction of future energy development strategies.

The construction of offshore wind power is of great significance to the realization of the “dual carbon” goal and the construction of a new power system with new energy as the main body. Far away from land and complex sea conditions make the control, operation and maintenance (O&M) of offshore wind turbines face many challenges, which are key issues that must be taken seriously and solved in large-scale construction. This paper summarized the current development trend of offshore wind power and related research progress, analyzed the main problems faced by the control and O&M of offshore wind turbines, and sorted out the key technologies of offshore wind power from two aspects of intelligent control and intelligent O&M,so as to provide reference for carrying out frontier theoretical and technical research in this field.

In order to achieve the goal of “carbon peak, carbon neutrality” and build a safe, stable, green and low-carbon modern energy system, lithium-ion batteries have attracted much attention as a typical electrochemical energy storage device. How to ensure the safe and stable operation of the power stations has become the primary issue with the scale of newly installed capacity expanding. Therefore, from the perspective of cell materials, aiming at the existing problems of commercial lithium battery separators, the work of intelligent separators in recent years was reviewed, including the modification of polyolefin separator materials, the design of new intelligent separator structures and the development of high temperature resistant polymer materials. The importance of developing high-safety separator materials was emphasized. Finally, the future research on separators of liquid and solid batteries was prospected, in order to provide a reference for further optimization and design of high-safety energy storage materials.

CO₂ mineralized all-solid waste alkali-activated cementitious materials can not only realize the storage of CO₂ mineralized, but also shorten the curing cycle of alkali-activated cementitious materials and improve their compressive strength. It is a promising way of CO₂ capture and utilization. The effects of the ratio of alkali-activated cementitious materials, mineralized curing pressure and mineralized curing time on the carbon fixation rate and compressive strength of CO₂ mineralized cementitious materials were studied. The results show that the calcium carbide slag as alkali activator is more suitable for mineralization curing, and the sample with the highest Ca/Si ratio has the best carbon fixation ability under the same curing condition. Increasing the curing pressure and curing time of CO₂ can improve the properties of the samples. Physical and chemical characterization test results show that, the microstructure of the mineralized samples is more compact than that of the natural curing samples, and the calcite-type calcium carbonate produced in the curing process is helpful to increase the compressive strength of the material. The research results provide basic data and reference for the development of CO₂ mineralization curing technology of all-solid waste alkali-activated cementitious materials.

In order to solve the problem that the current domestic and foreign electrical calculation methods have too high requirements for the input parameters of the planning power grid, the predicted load of the plot was transformed into the electrical calculation load, and the realization method of spatial distribution of the future load of the plot was proposed. On the basis of studying the classical reliability formula, the concept of comprehensive failure rate was proposed. Moreover, a more practical reliability engineering calculation formula was given, which simplifies the use conditions of the classical formula. The core algorithms of electrical integration calculation (including power flow, short circuit, reliability and N-\mathrm{1} verification), load forecasting and load space allocation algorithm were applied in the grid planning project of Dezhou Jinghua. The results show that the engineering implementation method is accurate and fast, and can meet the needs of power grid planning.

The CFD-DPM (computational fluid dynamics-discrete particle model) and the response surface methodology has been performed to optimize the geometrical ratios of cyclone separator. The research results illustrate that the most significant geometrical parameter is the vortex finder diameter. Other four factors have significant effects on the cyclone performance viz., the inlet width, inlet height, the cyclone total height, and the vortex finder length. In addition, there were strong interactions between the effect of the inlet width and inlet height, inlet dimensions and the vortex finder diameter on the pressure drop. There were strong interactions between the effect of the vortex finder diameter and inlet height, the vortex finder length and the cyclone total height on the separation efficiency. Finally, a new set of geometrical ratios was obtained to achieve minimum pressure drop and maximum separation efficiency. When the value of a/D, b/D, D_x/D, H/D, S/D was 0.40, 0.26, 0.34, 6.28, 0.66, respectively, the minimum pressure drop was 2.32kPa and the maximum separation efficiency was 99.27%.