The conventional flexible retrofit plan for coal motor sets is difficult to eliminate the potential life loss and equipment safety risks caused by frequent and rapid load changes to the thermal system. In order to improve the long-term safety and economy of coal-fired power units participating in deep peak shaving, a “healthy peak shaving” technical route for coal-fired power units based on hydrogen energy storage system is proposed, with a domestic ultra supercritical secondary reheat 1 000 MW coal-fired unit as the application object. The indirect carbon emission reduction significance of peak shaving coal-fired power hydrogen production is demonstrated. On this basis, the matching degree between different hydrogen production processes and the production conditions of coal-fired power plants were analyzed. It was believed that solid oxide electrolysis cell (SOEC) hydrogen production was the comprehensive optimal plan. Based on this, a principle design scheme for SOEC coupled coal-fired power peak shaving was proposed. Finally, a financial analysis was conducted on the new plan using the annual load curve. The calculation results indicate that, the SOEC assisted deep peak shaving of coal-fired power can increase the annual revenue of the example unit by 236 million yuan, and obtain other benefits such as equipment lifespan extension, consumption reduction, and carbon reduction. The relevant conclusions have reference significance for guiding the healthy and safe operation of peak shaving coal-fired power units.

Under the background of flexible peak regulation, in order to adapt to the dynamic change of direct air-cooled unit load and the interference of environmental factors, an online learning neural network method is proposed to predict the backpressure of direct air-cooled unit. Firstly, the historical data are cleaned and Spearman correlation analysis is used to determine the important features of low redundancy affecting backpressure. Then, the Hammerstein model is used to identify the model parameters online for the backpressure. At the same time, the backpressure prediction model of direct air-cooled unit is established by using long-short memory neural network and attention mechanism, and the model is updated by online learning. The experiments results show that, the model has an absolute percentage error (MAPE) of less than 9% in predicting backpressure at different time spans within the next 1 hour, and a MAPE of less than 1% in predicting backpressure within 30 seconds. Finally, the actual power plant system is used to verify that the model can run stably in practical applications. The results of this study provide an effective method for real-time prediction of the backpressure of direct air-cooled unit, which is of great significance for the operation and management of direct air-cooled unit with flexible peak regulation.

Under oceanic conditions, the coolant in the loop of a floating nuclear reactor (FNR) experiences periodic fluctuations, which affects the system’s thermal and hydraulic characteristics. A combination of theoretical derivation and numerical simulation is employed to investigate the velocity and temperature distribution characteristics within a pipe under pulsating flow conditions. Moreover, the influence of different numerical simulation boundary conditions on the velocity and temperature distribution in a circular tube under pulsating flow is compared. The results show that, under high-frequency pulsating flow conditions, laminar flow inside the pipe will experience backflow near the wall, and the wall effect will increase with the pulsation frequency. Using pulsating velocity inlet and pressure outlet as numerical simulation boundary conditions fails to predict this backflow phenomenon. However, employing fluctuating pressure inlet and flow outlet effectively captures the backflow occurrence in high-frequency pulsating flow. Concurrently, the temperature within the pipe fluctuates under pulsating flow conditions, and the amplitude of temperature fluctuations gradually decreases when the pulsation frequency increases. Numerical simulation can well simulate the temperature distribution in the pipe under pulsating flow conditions, with an error of less than 2%.The research results can provide reference for non-stationary numerical simulation methods.

Compressed carbon dioxide energy storage system has the advantages of large energy storage density, compact system equipment and long operating life. Expander is the key equipment of the energy storage system and has a direct effect on the efficiency and performance of the entire energy storage system. This article reviews the research status of various types of expanders. The working principle and characteristics of different types of carbon dioxide expanders are introduced. The expander types that can be used in compressed CO₂ energy storage systems are provided. The problems and their countermeasures of four kinds of expanders applied to energy storage systems were analyzed. The research direction of CO₂ expander is pointed out, including design method optimization, key component structure optimization, leakage, sealing, friction, and lubrication, and so on, which provides reference for the optimal design of the expansion machine of compressed CO₂ energy storage systems.

The “carbon neutralization and carbon peak” goal proposed in the 14th Five-Year Plan has a profound effect on the power industry in many aspects, the transformation of electricity to low carbon direction has become an irreversible mainstream trend. This paper expounds the low-carbon power plant, low-carbon power grid, low-carbon energy consumption and related evaluation technologies in the low-carbon electric power system, and shows that the system has high efficiency, clean and recyclable low-carbon attributes in terms of energy saving, emission reduction and environmental protection. At the same time, the effect of the change of international low-carbon forms on China and the related problems in the concrete implementation of the “carbon neutralization and carbon peak” policy are analyzed, it puts forward a new scientific thinking for the implementation of the “carbon neutralization and carbon peak” strategy and the low-carbon transformation of the power industry.

Rapidly growth of organic solid waste (OSW) has caused serious social and environmental issues. Co-combustion is an economical and environmental method to treat OSW. However, there will be a variety of heavy metals discharged with flue gas during combustion as OSW contains them. Therefore, this study conducted an experiment on the migration of heavy metals and generation of micro particles during the co-combustion of OSW and lignite. The results show that, the release of heavy metals during combustion not only depends on the concentration of heavy metal the fuel contains, but also on the chemical mechanism at high temperature. The content of Pb, Cd and As in the flue gas of blending fuel is obviously lower than that of sole OSW, but Cu, Zn, Co and Mn shows opposite tendency. In addition, the particle size distribution of the four fuels all shows a normal distribution at 800 ℃ and 850 ℃, but large particle size generates when the combustion temperature rises to 900 ℃.

CO₂ geological utilization and storage (CGUS) is an important technical means to achieve the goal of “carbon neutrality”. Solving the steel corrosion problem in the process of CGUS is crucial to reduce the risk of CGUS technology and achieve the large-scale promotion and application of CGUS technology. In this paper, the proposed reaction mechanism of CO₂ corrosion of steel is reviewed, and the main factors influencing CO₂ corrosion of steels are summarized. Moreover, the effects of CO₂ partial pressure, temperature, salinity and pH value, the CGUS environment containing impurities, fluid flow and other factors on steel corrosion behavior are clarified, and the main protective measures for CO₂ corrosion of steels are summarized. On this basis, the key research directions of steel subjected to CO₂ corrosion in CGUS environment are put forward. The directions include further exploration of the reaction mechanism of CO₂ corrosion of steels, quantitative study on the coupling effect of various environmental factors on the law and degree of CO₂ corrosion, as well as the development and application of corrosion protection technologies under high CO₂ concentration conditions.

In wind turbines, the aerodynamic efficiency of wind turbines is closely related to the aerodynamic performance of excellent airfoils. Taking the conventional airfoil of wind turbine as the research object, combined with airfoil parametric modeling and self-adaptive genetic algorithm, the high performance optimized airfoil is obtained. The fitting accuracy of the conventional NACA63418 airfoil is compared between the CST method and the improved Hicks-Henne type function method, and then the Hicks-Henne type function method is selected to model the NACA63418 airfoil. The automatic calculation of aerodynamic characteristics of airfoil is realized by the coupling of self-adaptive genetic algorithm and XFOIL software, and the design efficiency of airfoil is improved. It broadens the train of thought and improves the design efficiency for the theoretical design of airfoils.

Accurate carbon emissions data of gas units is one of the guarantees to ensure carbon trading. Many gas units recently installed online gas chromatography devices, so that the carbon emission is able to be real-time monitored from fuel part. For units that are not equipped with flue gas CO₂ monitoring system or have no enough equipment space, conversion with flue gas O₂ concentration is one of the feasible paths to monitor carbon emission from flue gas part. But whether direct measurement or conversion monitoring methods, there is still a lack of sufficient research on the deviation of continuous monitoring data from the fuel part and flue gas part. Therefore, for the gas units without capability to directly monitor flue gas CO₂ in the short term, this study takes the historical data of an F-class gas-steam combined cycle unit for the simulation, and conducts continuous simulation monitoring and analysis based on the conversion with flue gas O₂ concentration and online gas chromatography. It is found that there is no stable sorting rule of the monthly data and the relative deviation between different calculation methods. All the relative deviation of annual data is less than 5%. The correlation between δ_{RD,R,fluegas-flue-h} and the O₂ concentration of CEMS is the highest. The deviation of carbon emission amount in the unit is mainly in the stable combustion section with a load ratio of more than 55%. In accordance with current standards or specifications, the O₂ concentration of CEMS and the wet flue gas flow rate at the chimney outlet is most likely to cause the deviation of carbon emission amount from the fuel part and flue gas part. Under the existing technical specifications, the carbon emission from fuel part and flue gas part can be monitored in real time, which can be used for analysis on trend, but only the uncertainty of result from fuel part is below 5%. For gas units, the carbon emission monitored at fuel part is more appropriate, and the method monitoring the flue gas part may be more suitable for coal-fired units.

Clarifying the driving factors for promoting low-carbon technology innovation in the power generation industry, and exploring incentive mechanisms for low-carbon technology innovation in the power generation industry, is of great significance for achieving the unity of economic, environmental, and social performance in the power industry, and ultimately achieving the “dual carbon” goal of the country. This article focuses on the characteristics of technological innovation in the power generation industry, starting from the two stages of low-carbon technological innovation, and based on external driving forces and internal driving forces of enterprises, it proposes 11 incentive factors to construct an internal and external collaborative incentive mechanism for low-carbon technological innovation in the power generation industry. The results show that, with the synergistic effect of the low-carbon technology innovation incentive mechanism in the power generation industry, the innovation research and development level of low-carbon technologies of enterprises can be promoted, and the economic, environmental and social performance of the enterprises can be improved through the transformation of low-carbon technology achievements. Therefore, an organic unity of enterprise development, environmental improvement and social progress is realized ultimately.