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About Journal

Bimonthly Publication,Start in 2014.12
Supervisor:China Southern Power Grid Digital Media Technology Co., Ltd.
Sponsor:
China Energy Construction Group
Guangdong Electric Power Design and Research Institute Co., Ltd.
Editor:Editorial Board of S. ENERGY CONSTR.
Publisher:Energy Observer Magazine Co., Ltd.
Honorary Chairman:DU Xianwan
Chairman:PENG Xueping
Co-Editor-in-Chief:YANG Yongping,  FAN Yongchun 
Associate Editor:ZHANG Chunwen
Editorial Director:ZHENG Wentang
Address:1 Tianfeng Road, Science City, Huangpu District, Guangzhou, P. R. China
Tel:+86-20-32116683; 32115630
ISSN 2095-8676
CN 44-1715/TK
CODEN: NFNYJK
Email:nfnyjstg@gedi.com.cn
Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Display Method:
Development Status and Trends of the ECH Technology for the Magnetic Confinement Fusion
XIA Donghui, LU Jing, CHEN Xixuan, FANG Xinyu
Accepted Manuscript  doi: 10.16516/j.ceec.2024-061
[Abstract](43) [FullText HTML](12) [PDF 2445KB](2)
Abstract:
  Introduction  In magnetic confinement fusion research, electron cyclotron heating (ECH) and current drive means are widely implemented for applications including, but not limited to, plasma initiation, heating, non-inductive current drive, and magnetohydrodynamic instability control. In recent years, ECH-related technologies have experienced significant development in response to the development needs of future fusion reactors, and ECH has become one of the main auxiliary heating means in magnetic confinement fusion devices.   Method  Firstly, the ECH system was introduced, and its components, characteristics and application status were described; then the development status and trends of ECH system-related technologies were discussed with emphasis on four aspects.   Result  Combined with the research status and application requirements of ECH-related technologies, the important and difficult points in developing each related technology are identified.   Conclusion  Based on the development status and trends of ECH-related technologies, the article forecasts future research directions and applications of ECH system-related technologies in diverse aspects, including high-frequency and multi-frequency gyrotrons (microwave sources), the intelligent control technology of ECH system, the high-efficiency current drive technology, and the gyrotron-based collective Thomson scattering technology.
Analysis of Flexible Peak Shaving Technology for Coal-Fired Boilers Based on Intelligent Control
SONG Minhang, YANG Hongyan
Accepted Manuscript  doi: 10.16516/j.ceec.2023-347
[Abstract](11) [FullText HTML](7) [PDF 3927KB](1)
Abstract:
  Introduction  With the increasing demand for flexible peak shaving of thermal power units and the rapid development of information technology, thermal power enterprises are shifting from the traditional operation and management mode toward a cleaner, more efficient, reliable digital and intelligent mode. How to improve the intelligence, precision and reliability of coal-fired units in the flexible peak-shaving process has become a key issue of concern to those in the industry.   Method  Aiming at the deep peak shaving of coal-fired units, this paper first summarized the typical problems in the process of flexible peak shaving, and analyzed the overall development of control theory applied to boilers. Based on this, this paper conducted a comprehensive analysis of coal-fired boiler flexible peak shaving algorithm models and their applications based on intelligent control from four aspects: optimization control of boiler combustion performance, precise control of wide-load denitration, boiler operational energy efficiency control, and monitoring and diagnosis of main and auxiliary machinery equipment.   Result  On this basis, the research progress and application effects of intelligent control theory and models in the flexible peak shaving of coal-fired boilers are discussed in detail.   Conclusion  At present, based on the common problems in the flexible peak-shaving process of coal-fired boilers, it is necessary to improve the accuracy of basic data acquisition, promote the complementary integration of data and knowledge, and strengthen multi-objective optimization control and DCS control system optimization on the basis of the stable combustion ability improvement of the combustion organization method. At the same time, it is important to consider the dialectical optimization relationship between peak shaving economy and unit life, thereby providing intelligent and precise solutions to improve the flexible peak shaving capabilities of coal-fired boilers.
An Inertial Electrostatic Confinement Fusion with Inner Ion Source
LI Jinhai
Accepted Manuscript  doi: 10.16516/j.ceec.2024-012
[Abstract](5) [FullText HTML](5) [PDF 2903KB](0)
Abstract:
  Introduction  The inertial electrostatic confinement (IEC) fusion facility is a small fusion device. This paper aims to solve the problems of IEC fusion devices, such as the cathode melting, the very low Q value, and so on.   Method  This paper first analyzed the reasons for these problems, and then a new type of inner ion source IEC fusion was proposed to decrease the ion loss during the confinement process, solve the cathode melting, and increase the vacuum in the device and the Q value.   Result  At last, the improvement of neutron yield is qualitatively analyzed through the estimation, the very complex ion motion inside the fusion device is simulated through numerical simulation calculation, and anisotropic ion motion trajectories are obtained.   Conclusion  Based on estimation and numerical simulation results, the feasibility of the IEC with an inner ion source is confirmed, which can solve the problems of cathode melting and low Q value.
Optimization of Electromagnetic Field Distribution of 120 kA Pulse Inductor in Oscillation Discharge Circuit
LI Zhenhan, LI Hua, BAO Xiaohua, GAO Ge
Accepted Manuscript  doi: 10.16516/j.ceec.2024-024
[Abstract](14) [FullText HTML](5) [PDF 4061KB](0)
Abstract:
  Introduction  Pulse inductor is an important component of the oscillation discharge circuit in the quench protection system. In the oscillating discharge circuit, the pulse inductor and charging capacitor are used to oscillate and generate high pulse currents, causing the current flowing through the vacuum circuit breaker to reverse and create an artificial zero-crossing point, thus completing the switch breaking. However, under the condition of 120 kA current, due to the action of the electromagnetic force, the connecting bar below the pulse inductor will deform, causing equipment damage and greatly reducing the reliability of the auxiliary oscillation zero-crossing circuit. Therefore, it is necessary to conduct electromagnetic field analysis on the 120 kA pulse inductor and optimize the electromagnetic field distribution around it.   Method  Firstly, the commutation process of the auxiliary oscillation zero-crossing circuit was analyzed to establish a three-dimensional model of the pulse inductor, and the concept of magnetic field shielding percentage was introduced. Secondly, the influence of shielding plates with different materials and shapes on electromagnetic field distributions was calculated by using finite element simulation. Then the influence of different materials and shapes on shielding percentage was analyzed, and eddy current losses under different shapes were calculated. Finally, the deformation degree of the connecting bar under different shielding structures was calculated in the structural module.   Result  The results show that the use of different materials or structures in the shielding plates influences the magnetic induction intensity and electromagnetic force received by the connecting bar.   Conclusion  The circular aluminum shielding plate has a better optimization effect for the electromagnetic field distribution. This method also lays a foundation for the electromagnetic shield design of pulse inductors.
Practice and Research of Floating Offshore Photovoltaic Intelligent Climate Early Warning Platform
ZHOU Chengsheng, FANG Shidong
Accepted Manuscript  doi: 10.16516/j.ceec.2023-277
[Abstract](109) [FullText HTML](272) [PDF 2717KB](153)
Abstract:
  Introduction  This paper aims to explore a novel floating offshore photovoltaic system that not only effectively collects marine solar energy but also performs intelligent climate early warning.   Method  By integrating offshore photovoltaic technology with intelligent meteorological monitoring technology, we developed a viable intelligent offshore photovoltaic climate early warning platform. Firstly, the floating offshore photovoltaic platform was used to convert solar energy into electrical energy. Secondly, the intelligent monitoring system monitored ocean weather conditions in real-time and gave early warnings to improve the reliability of photovoltaic power generation.   Result  Tests show that the floating offshore photovoltaic system can effectively collect solar energy under different sea areas and weather conditions, and the intelligent meteorological monitoring system is used to timely give early warnings on the changes in marine meteorology.   Conclusion  This study finds that the platform has broad application prospects and market potential. It can provide references for the development of marine renewable energy and provide ideas and methods for related research and practice.
Application of Wide Spectrum Conjugated Small Molecule for High Efficiency Solar-Powered Seawater Desalination and Power Generation
ZHU Jingshuai, QIU Xiaopan
Accepted Manuscript  doi: 10.16516/j.ceec.2023-148
[Abstract](105) [FullText HTML](41) [PDF 1772KB](21)
Abstract:
  Introduction  In order to solve the problems of high cost and complex preparation process of solar desalination devices, organic small molecule photothermal materials, which possess advantages such as light weight, low cost, simplified synthesis and purification processes, are selected as solar energy absorption materials.   Method  A kind of organic conjugated small molecule Y6 was combined with a low-cost cellulose paper to prepare a Janus structure water evaporator with wide spectrum absorption in the range of 350~1 000 nm and high photothermal conversion performance.   Result  The bottom surface of the evaporator has efficient water adhesion, facilitating rapid water collection, while the top surface has water repellency, which can achieve the self-floating ability. Moreover, each 3.14 cm2 device only needs 0.5 mg photothermal material to achieve a temperature of more than 70 ℃, demonstrating significant material-saving advantages.   Conclusion  Under 1.0 kW/m2 solar irradiation, the photothermal conversion efficiency of Y6-based evaporator is 64.4%, and the evaporation rate is up to 1.13 kg/(m2·h), which is obviously higher than that of the control cellulose paper evaporator. After solar evaporation desalination, the purified water obtained exhibits a significant reduction in ion concentration by 4~6 orders of magnitude compared to the initial simulated seawater. When the evaporator is integrated with a thermoelectric device, the evaporation rate reaches 1.02 kg/(m2·h) under 1.0 kW/m2 solar irradiation. Meanwhile, an output voltage of 55 mV is generated. This study demonstrates that the solar evaporator based on organic small molecule Y6 has a promising application prospect in the synergistic effect of photothermal water purification and thermoelectric power generation.
Research on Carbon Emission Accounting and the “Dual Carbon” Transformation Path of Industrial Parks
WANG Zhong, MA Siming, WANG Tingting, TAO Wei, XU Jing
Accepted Manuscript  doi: 10.16516/j.ceec.2023-311
[Abstract](188) [FullText HTML](50) [PDF 1124KB](29)
Abstract:
  Introduction  As an important carrier of China's industrialization and urbanization, industrial parks not only provide a large amount of infrastructure and public services, but also become the main source of carbon emission in China and an important entry and focus point for achieving China's goals of carbon peaking and carbon neutrality. The paper proposes a theoretical research framework for analyzing the transfer process of carbon emission in industrial parks and optimizing the decision-making process of the "dual carbon" path, in order to achieve the refined management of carbon emission in industrial parks.   Method  Firstly, we analyzed the carbon emission characteristics of energy, industry, construction, transportation, and infrastructure in industrial parks, and established a carbon emission accounting model for industrial parks based on inventory analysis method. Secondly, considering the impact of factors such as gross industrial output value, industrial structure, energy structure, and energy consumption on carbon emission, we established a decomposition model of factors influencing carbon emission based on the STIRPAT method. Finally, we analyzed the mechanism and impact path of digital technology empowering green and low-carbon transformation, and proposed the optimization plan for decision-making of the "dual carbon" path.   Result  Taking Ganzhou Economic and Technological Development Zone in Jiangxi Province as the research object, we calculated the carbon emission and carbon emission intensity from 2020 to 2022, identified the main factors influencing the increase of carbon emission, and planned the "dual carbon" transformation path from four aspects: industrial structure, energy structure, policy system, and platform construction.   Conclusion  Research suggests that the proposed model can fully explore the information contained in statistical data of industrial parks and is scientific and effective, providing theoretical support for the decision-making of "dual carbon" transformation path and the construction of industrial internet platform for digital carbon management of industrial parks.
Nonlinear Evolution of Double Tearing Mode Mediated by Parallel Electron Viscosity
HE Zhixiong, DONG Jiaqi, JIANG Haibin
Accepted Manuscript
[Abstract](193) [FullText HTML](78) [PDF 5497KB](258)
Abstract:
  Introduction  By adding parallel electron viscosity into the normal equation of resistance tearing mode, the nonlinear behavior of double tearing mode (DTM) mediated by parallel electron viscosity is numerically investigated considering the magnetohydrodynamics in a periodic cylinder.   Method  The evolution of magnetic islands and magnetic flux during the nonlinear behavior stage of double tearing mode mediated by parallel electron viscosity were analyzed, to study the changes of the magnetic field topology in different phases and associated kinetic characteristics for different distances between the two resonant rational flux surfaces. In addition, the nonlinear driving for each case was discussed.   Result  The results show that the distance between the two resonant rational flux surfaces has a significant impact on the nonlinear behavior of double tearing mode. Rapid magnetic reconnection would occur at intermediate distance, resulting in the fastest and most severe damage to the configuration.   Conclusion  The results of this study provide a reference for the configuration design and operational control of tokamaks.
Strategies for Improving the Safety and Operational Reliability of High-Voltage Frequency Converters
LI Tonglin
Accepted Manuscript  doi: 10.16516/j.gedi.issn2095-8676.****.**.***
[Abstract](49) [FullText HTML](37) [PDF 1017KB](8)
Abstract:
  Introduction  "Energy saving and emission reduction" is the national technical requirement for industrial projects in recent years, and the frequency conversion technology can make process equipment adjust output under different working conditions, thereby saving resources. However, frequency converters are power electronic devices, and the failure rate of IGBT components is relatively high, and the requirements for the operating environment are harsh. Therefore, it is very important to improve the safety and operational reliability of high-voltage frequency converters.   Method  In the case of failure of individual power units of the high-voltage frequency converter, according to the neutral point drift technology, the position of the neutral point and the angle between the three-phase voltages are adjusted, so that the high-voltage frequency converter can bypass some faulty power units can still operate normally; Send the real-time status of the high-voltage inverter to the DCS, and realize the automatic bypass technology of the high-voltage inverter according to the logic configuration of the DCS; Set up a separate high-voltage inverter room to provide a relatively good operating environment for high-voltage inverters through air conditioning, ventilation, and air duct systems.   Result  After adopting the internal strategy and external environment strategy for the high-voltage inverter, the failure rate of the high-voltage inverter is reduced, and the safe operation time of the high-voltage inverter is prolonged.   Conclusion  The use of neutral point drift technology and the automatic bypass technology of the whole machine can reduce the failure probability and frequency of high-voltage inverters, and jointly improve the temperature and humidity conditions of the operating environment, which can increase the continuous and reliable operation time of the inverter, to greatly improve the safety and operation reliability of inverters.
Quench Voltage Detection for Superconducting Magnets in Tokamak
WANG Teng
Accepted Manuscript  doi: 10.16516/j.ceec.2024-092
[Abstract](6) [FullText HTML](5) [PDF 1725KB](0)
Abstract:
  Introduction  The superconducting tokamak serves as the foundation for steady-state operation. Timely and reliable quench detection is the key to ensuring the secure operation of superconducting magnets, which has the highest level of safety in fusion device operation.   Method  This paper provided an overview of the principles and implementation approaches of the quench voltage detection for fusion magnets. It briefly summarized the research progress of quench detection and the quench detection schemes adopted by mainstream tokamak devices, and introduced the basic principles and processes of quench voltage detection. Taking the experimental advanced superconducting tokamak (EAST) as an example, this paper analyzed the interference sources and coupling mechanisms of quench voltage detection, proposed a two-stage decoupling compensation scheme, and established an optimization analysis model for primary compensation and a dynamic compensation mechanism for plasma-coupling interferences.   Result  The experimental results indicate that the compensation scheme can achieve high noise suppression ratio greater than 99.9%, which can effectively improve the signal-to-noise ratio (SNR) and reliability of quench detection.   Conclusion  The established optimization analysis model for primary compensation and the dynamic compensation mechanism for plasma-coupling interferences can be extended to other tokamak devices, thereby providing necessary accumulation for the design of quench detection and the secure operation of magnets in future fusion reactors.
Failure Analysis and Shielding Effectiveness Study of Magnetic Components in Strong Magnetic Environments for Magnetic Confinement Fusion Devices
HUANG Ya, HUANG Zhengyi
Accepted Manuscript  doi: 10.16516/j.ceec.2024-051
[Abstract](6) [FullText HTML](4) [PDF 4357KB](0)
Abstract:
  Introduction  The purpose of this study is to explore the impact of the spatial magnetic field generated by nuclear fusion devices on magnetic devices and to gain an in-depth understanding of the magnetic field shielding characteristics in a complex electromagnetic environment.   Method  In the research process, the switch power supply and electronic transformer in the nuclear fusion internal power supply system were selected as the specific research objects. By analyzing in detail the impact of the magnetic field on the loss and the characteristic changes under different directions of the magnetic field, as well as by exploring the key factors affecting the magnetic field shielding effectiveness and the application of different materials, the research objectives were achieved.   Result  The results indicate that the loss of magnetic components significantly increases in a strong magnetic field environment, and the degree of influence of different directions of magnetic fields on component characteristics varies. By comparing and analyzing the shielding effects of different materials, it is found that materials with high conductivity and magnetic permeability have better application prospects in shielding design. Additionally, optimizing the shielding structure can further improve shielding effectiveness and reduce the impact of magnetic fields on magnetic components.   Conclusion  By systematically analyzing the impact of strong magnetic fields on magnetic components and the shielding effectiveness of nuclear fusion devices, key references are provided for testing the equipment's magnetic field tolerance and verifying shielding design. Future work will focus on further optimizing shielding materials and structural design to improve the stability and reliability of magnetic components in strong magnetic field environments.
Research on Optimization of Three-Circuit Parameters for Thermonuclear Fusion Power Generation Island
LUO Xianyong, LI Bin, LIN Yan, XIANG Kui, ZHU Guangtao
Accepted Manuscript  doi: 10.16516/j.ceec.2023-351
[Abstract](7) [FullText HTML](5) [PDF 1672KB](0)
Abstract:
  Introduction  In order to adapt to the periodic output characteristics of CFETR fusion reactors, the fusion power plant adopts a helium-molten salt energy storage-water (steam) power cycle three-circuit system. The parameters and thermal scheme of the three-circuit steam cycle have a significant impact on the investment and power generation benefit of the power generation island. High parameters and complex thermal schemes can improve cycle efficiency but increase initial investment; low parameters and simple thermal schemes have lower cycle efficiency but significantly reduce initial investment. Therefore, the selection of steam parameters and thermal schemes for the three-circuit system should comprehensively consider power generation efficiency and initial investment and should be selected based on the principle of optimal comprehensive economy.   Method  Based on the simulation software Ebsilon, modeling and simulation were carried out in this study to examine the performance of the thermal cycle under different regeneration schemes and different main steam and reheat parameters. By calculating different thermal schemes and parameter combinations, the total efficiency and output power under each operating condition were obtained, and the investment in the main equipment of the three-circuit system and its variation with parameters were analyzed.   Result  Taking into account the total investment and returns of the energy storage island and the conventional island, it is recommended to adopt a thermal scheme with 9-stage regeneration, and main steam parameters of 12.4 MPa, and 540 ℃.   Conclusion  The three-circuit steam parameters and thermal scheme proposed in the study have reference value for subsequent research on fusion power generation technology and engineering design.
Research on Operation Mode of Energy Storage System for Thermonuclear Fusion Power Plant
LIN Yan, LI Bin, LUO Haodong, XIANG Kui, ZHU Guangtao
Accepted Manuscript  doi: 10.16516/j.ceec.2023-327
[Abstract](25) [FullText HTML](8) [PDF 1016KB](1)
Abstract:
  Introduction  As a new form of nuclear energy utilization that is green and clean, nuclear fusion is regarded as the "ultimate energy" of mankind in the future and also as an inevitable route for China's energy development. In thermonuclear fusion power plants, China Fusion Engineering Test Reactors (CFETR) have periodic and pulse energy output, while turbine generator units operate stably and continuously. Therefore, an energy storage island is required between a nuclear island and a conventional island for energy storage buffering. To realize such a buffering function, a suitable operation mode needs to be selected for the energy storage system.  Method  The coupling and decoupling operation of the nuclear island and conventional island corresponded to different operation modes of the energy storage island. Based on the power output characteristics of CFETR, different operation mode schemes were analyzed and compared from aspects such as system configuration, equipment design and operation control.   Result  The results show that the decoupling operation mode of a nuclear island and conventional island is superior in terms of power generation efficiency, maturity of equipment design technology and operation control of generator units, so it is recommended to adopt the decoupling operation mode for the energy storage system in a thermonuclear fusion power plant.   Conclusion  Most of the decoupling operation mode schemes for the energy storage system adopt mature technologies, so they can be put into commercial applications on a large scale and provide support for the commercial design of thermonuclear fusion power plants.
Lightning Protection Design of Offshore Floating Photovoltaic Power Station
ZHOU Chengsheng
Accepted Manuscript  doi: 10.16516/j.ceec.2023-132
[Abstract](5) [FullText HTML](6) [PDF 2631KB](1)
Abstract:
  Introduction  This paper mainly discusses the principles, methods and measures of lightning protection design of offshore floating photovoltaic power station to meet the safe operation of offshore floating photovoltaic power station in harsh climate conditions.   Method  Through the in-depth analysis of the marine environment, offshore floating photovoltaic power station structure and lightning characteristics, this study proposed a series of effective lightning protection measures. First, the use of metal structure could improve the lightning resistance capacity of the floating photovoltaic power station. Secondly, the installation of lightning rods could absorb and release lightning energy, reduce the impact of lightning on the power station. In addition, the establishment of the ground grid could effectively disperse the ground potential and reduce the risk of lightning strike. The use of insulating materials helped to reduce the direct invasion of lightning on the power station equipment. At the same time, the installation of monitoring equipment could be real-time monitoring of lightning activities, timely response measures. Regular inspection and maintenance was an important part to ensure the stable operation of the lightning protection system.   Result  The principle and implementation method of each lightning protection measure are elaborated, and some technical problems in lightning protection design are proposed. For example, how to ensure the good grounding of the lightning rod, how to choose the appropriate insulation material, etc. These achievements provide an effective reference for the improvement of the lightning protection capacity of the offshore floating photovoltaic power stations.   Conclusion  The results of this study will help to improve the lightning protection capacity of the offshore floating photovoltaic power stations and ensure the safe operation of the power stations. Based on full consideration of the marine environment, the structure of the offshore floating photovoltaic power station and the lightning characteristics, the appropriate lightning protection measures can effectively reduce the risk of lightning strike and ensure the stable operation of the power station. This is of great significance for promoting the development of renewable energy and protecting the environment. Further study can provide more reference and guidance for lightning protection design to cope with the more complex and harsh climate conditions in the future.
Conceptual Design of Novel Fusion Power Supply with Energy Storage
SU Hang, LI Hua, SONG Zhiquan, XU Meng, LI Zhenhan, WU Qiankun
Accepted Manuscript  doi: 10.16516/j.ceec.2024-029
[Abstract](33) [FullText HTML](5) [PDF 1827KB](1)
Abstract:
  Introduction  In recent years, as the installed capacity of the fusion device has been increasing, the power supply system of the device requires high-amplitude and long-pulse power output, which causes a strong power impact on the grid, and even power supply disconnection in severe cases to pose a serious threat to the safety of the fusion device. Additionally, the high-amplitude pulses also result in a lot of redundancy in the power supply system design.   Method  To solve these problems, this paper proposed a novel fusion power supply topology with energy storage, that is, the power supply system was designed with energy storage to mitigate the impact of pulse power on the grid. During the operation of the power supply, the grid provided steady-state power while the energy storage device delivered pulse power, effectively reducing the cost of the power supply.   Result  According to the experience in industrial power supply and distribution, this paper presents the calculation formulas for the selection of key components in different topologies and conducts a cost analysis and comparison for different power supply topologies based on simulation data.   Conclusion  The experimental results show that the new power supply topology not only reduces the power impact on the grid and improves the energy utilization of the power supply system, but also reduces transformer capacity, thus it is cost-efficient.
Carbon Reserve and Carbon Sink Potential Estimation of Mangrove in Guangdong Province
SU Siqi, ZOU Guanhua, YU Yunjun, WEN Fang, ZHANG Naiwen
Accepted Manuscript  doi: 10.16516/j.ceec.2024.5.06
[Abstract](46) [FullText HTML](21) [PDF 810KB](4)
Abstract:
  Introduction  The mangrove ecosystem has a high carbon sequestration capacity and is an important part of the global carbon cycle. Exploring its carbon sink potential can promote the mitigation and adaptation to climate change, providing a potential marine solution for China's carbon peak and carbon neutralization.   Method  In this study, the methodology of mangrove blue carbon assessment was studied to estimate the carbon reserve and carbon sink potential in Guangdong Province.. The carbon reserve in mangroves in Guangdong Province was about 3 222 034.79 t C, of which the carbon reverse in vegetation was about 1 094 464.79 t C and the carbon reserve in soil was about 2 127 570 t C. Among different mangrove communities, the vegetation carbon reserve of Aegiceras corniculatum was the highest, reaching 1 508 930.79 t C, followed by Avicennia marina, Kandelia obovata and Sonneratia apetala, with carbon reserve of 1 508 930.79 t C, 859 115.16 t C, 193 295.54 t C and 660 693.3 t C respectively.   Result  According to the " Special Action Plan for Mangrove Protection and Restoration (2020-2025)", by 2025, 55.00 km2 of mangroves will be planted in Guangdong Province, and the carbon sink potential can increase by 36 171.49 t CO2-e ~99 890.67 t CO2-e, with great carbon sink potential.   Conclusion  This study can provide scientific basis for the afforestation of mangrove carbon sink in Guangdong Province, and is of great significance for China's carbon peak and carbon neutrality cause.
Cover & Contents
Cover & Contents
2024, 11(2)  
[Abstract](51) [PDF 5911KB](24)
Abstract:
Marine Energy and Marine Ranch
Development Trend and Technical Challenges of the Integration of Offshore Wind Turbine with Marine Ranch
YANG Jie, ZHANG Jianhua, MA Zhaorong, LIU Donghua, WANG Hongqing, YIN Ziwei
2024, 11(2): 1-16   doi: 10.16516/j.ceec.2024.2.01
[Abstract](241) [FullText HTML](66) [PDF 9724KB](71)
Abstract:
  Introduction  Under the background of "carbon peak and neutrality" target and "ocean power" strategy, the integration of ocean renewable energy represented by offshore wind power and ocean resources represented by marine ranch is the new direction, new situation and new opportunity for the future development and utilization of ocean resources. The article reviews and analyzes the integrated development mode and key technical problems of offshore wind power and marine pasture, in order to provide technical references to the relevant research and engineering projects in China.   Method  Taking the integration of China's marine resources development needs as the guide, the global development trend of offshore wind power and marine ranch integration was analyzed, and the current situation and shortcomings of China's wind-fishery integration development were clarified. On this basis, the integration mode, equipment design, engineering cases and key technical problems of the integration development of offshore wind power and ocean ranch were analyzed in detail. Finally, a future outlook on the integration development of offshore wind power and ocean ranch in China was discussed.   Result  Through the analysis of the integrated development mode and key technical problems of the integration of offshore wind power and marine ranch development, the bottlenecks and technical challenges are clarified, and the key breakthrough directions are pointed out, providing scientific guidance and reference basis for the comprehensive development and utilization of offshore resources in China.   Conclusion  The article illustrates the necessity and feasibility of integrating the development of offshore wind power and marine ranch, and proposes a feasible way to integrate offshore wind power and marine ranch in China.
Comparision of Integrated Towing Motion Performance for Multi-Column Semisubmersible Floating Offshore Wind Turbines
QI Xiling, LE Conghuan, REN Jianyu, ZHANG Puyang, DING Hongyan, QI Xiaoliang
2024, 11(2): 17-30   doi: 10.16516/j.ceec.2024.2.02
[Abstract](158) [FullText HTML](54) [PDF 3069KB](34)
Abstract:
  Introduction  A comparative research was conducted to investigate the variation rules of motion responses in various degrees of freedom (DOF) and towline forces in the towing process of three-column submerged floating offshore wind turbines (TC-SFOWT) and four-column submerged floating offshore wind turbines (FC-SFOWT) under different working conditions, through a physical model test using a DTU 10 MW wind turbine.   Method  Firstly, a free attenuation test was carried out in still water. Then towing process tests were carried out in regular wave and irregular wave environments. The research focuses on the effects of different towline point heights, wave heights, and wave periods on the towing process of SFOWTs.   Result  These tests yielded the following findings. (1) The analysis related to heave, roll, and pitch natural vibration periods of SFOWTs reveals that the difference in natural vibration periods between the two SFOWT structures in the same DOF is within 5 seconds, the TC-SFOWT exhibits a smaller heave acceleration and longer natural periods of pitch and roll; (2) As wave height increases, the response of SFOWTs in each DOF and the towline force also increase, and the increase in wave height has a greater influence on the heave acceleration and roll angle of the TC-SFOWT under both regular wave and irregular wave conditions, while it has a smaller impact on the pitch angle and towline force; (3) When the wave period differs greatly from the natural period of SFOWTs, an increase in wave period results in a decreasing trend in the SFOWTs' responses across various DOFs, except for heave acceleration; (4) When the towline point is flush with the water level, the towline force amplitudes of the TC-SFOWT and FC-SFOWT are respectively 11.1% and 14.7% lower than those of the other two working conditions.   Conclusion  In conclusion, the towing motion performance of the FC-SFOWT is better. In actual engineering practices, the towline point height when the structure is self-floating should be arranged at the water surface line, so as to reduce motion response during the towing process.
Integrated Calculation and Coupled Dynamic Analysis of a Concrete Semi-Submersible Floating Wind Turbine in Offshore Deep Water Area
CHEN Jiahao, GAO Yifan, YIN Ziwei, ZHENG Can, QU Xiaoqi
2024, 11(2): 31-41   doi: 10.16516/j.ceec.2024.2.03
[Abstract](191) [FullText HTML](31) [PDF 3762KB](46)
Abstract:
  Introduction  The research aims to explore the integrated calculation method of a 10 MW semi-submersible floating wind turbine, and analyze its coupled dynamic response characteristics in 40~50 m offshore deep water areas.   Method  A 10 MW concrete semi-submersible floating wind turbine was taken as an example, and then numerical calculation was carried out by the integrated calculation method, and its coupled dynamic response under rated and survival conditions was statistically analyzed.   Result  The horizontal motion of the platform is mainly affected by the wave force, wind loading and mooring stiffness. The maximum value of motion and mooring tension occur in the survival condition, and the heave motion is mainly affected by the wave, but the mean value of the pitch/roll motion is mainly affected by the wind loading, all of which meet the design specification.   Conclusion  The integrated calculation method better considers the coupled dynamic behavior of floating wind turbines. Due to the limitation of water depth, the optimization of horizontal motion and mooring nonlinearity of offshore floating wind turbines is more important in offshore deep water areas, and the extreme response mainly occurs in survival conditions. The above conclusions provide an important reference for the research and design of the floating offshore wind turbines in offshore deep water area.
Prospect of Offshore Floating Photovoltaic Power Generation Technology and Its Integrated Development
YUE Yunfeng, PENG Xinran, WANG Hongqing, LU Bin
2024, 11(2): 42-50   doi: 10.16516/j.ceec.2024.2.04
[Abstract](289) [FullText HTML](469) [PDF 1465KB](99)
Abstract:
  Introduction  Under the backdrop of "carbon peak and neutrality", coastal provinces and cities in China are gradually developing clean energy towards the ocean. The development of offshore wind farm has begun to take shape and achieved equal price of connection to power grid, and pilot projects for offshore floating photovoltaic (FPV) systems are emerging. The comprehensive development of a variety of marine resources, the intensive use of sea resources in the energy sector, and the creation of an integrated marine energy system are of great significance for coastal provinces to achieve high-quality carbon neutrality.   Method  The article summarized the current development and pilot projects of offshore FPV technology both inside and outside of China, analyzed the advantages and challenges of various offshore FPV technologies, predicted the future market size of offshore FPV in China, explored the integration development mode of offshore FPV and other offshore infrastructure, and provided the integration scenarios and economic analysis based on case studies.   Result  The offshore FPV technology is currently at the pilot stage with broad market in the future. The main technical challenge is the viability of floating structure under harsh marine environmental conditions, and the unit cost of the existing pilot projects is relatively high, however, it has enormous potential of combination with other marine facilities.   Conclusion  The integration of offshore FPV and other offshore facilities such as offshore wind power can effectively improve the utilization efficiency of energy facilities and reduce the cost of construction and operation. The complementary use of marine scenery also effectively solves the stability and security problems of a single energy supply.
Research on Offshore Wind Power Communication System Based on 5G Technology
LI Tonglin, ZENG Fulong
2024, 11(2): 51-58   doi: 10.16516/j.ceec.2024.2.05
[Abstract](86) [FullText HTML](48) [PDF 2756KB](24)
Abstract:
  Introduction  Numerous equipment of offshore wind power projects is located on the ocean, and the inconvenient transportation makes operation and maintenance difficult. It is extremely important for offshore equipment information to be delivered to land quickly, without delay, and safely. In view of the special needs of the communication system, a communication system scheme for offshore wind farms based on 5G technology is proposed.   Method  First, a PTN+ integrated small base station with large signal coverage and strong reliability was built, and then the 5G integrated small base station with the PTN gateway were integrated to achieve fast and convenient 5G signal coverage through broadband PTN access. The 5G network with specific bandwidth improved the security of the communication system.   Result  After the completion of the 5G communication system based on PTN+ integrated small base station, IP transmission based on optical transmission, supporting multiple services and using specific bandwidth can be realized. This system can help plan and sort out the wind turbine subsystems, realize all-round signal coverage inside the wind turbine, and can quickly and safely transmit the operation status and data of wind turbines, offshore booster stations and other equipment to the onshore operation and maintenance center. This system can solve the problem of difficult real-time secure transmission of wind turbine multi-subsystems and multi-services.   Conclusion  The 5G communication system research improves offshore wind power communication, and uses specific bandwidth and emerging technologies to realize the timeliness and reliability of communication in offshore wind farms and improve the communication efficiency of offshore operation and maintenance personnel in offshore wind farms. It meets the communication requirements of offshore equipment in offshore wind power projects and is expected to be applied in engineering.
Site Selection and Layout of Distributed Offshore Wind Power Based on Energy and Transportation Integration
WANG Qingqin, WEN Guobiao
2024, 11(2): 59-67   doi: 10.16516/j.ceec.2024.2.06
[Abstract](92) [FullText HTML](44) [PDF 2633KB](26)
Abstract:
  Introduction  In the backdrop of the increasingly scarce availability of sea-based wind farms in near-sea shallow water areas and the trend towards deeper and wider waters, as well as larger and more concentrated facilities, a discussion is presented on a distributed offshore wind energy system that integrates energy and transportation, in order to avoid the commonly encountered issues of large-scale offshore wind farms in open waters, such as extensive sea-area requirements and impacts on shipping safety.   Method  Based on the existing or planned offshore wind farms in large ports, the best site was selected based on the built-in breakwaters that accompanied the port. After analyzing the functions and layouts of the port basin and the breakwater, the optimal layout of the offshore wind turbines and seabed cables was achieved through optimization. This could lead to improvements in technology, economics, policy, and environment in various aspects.   Result  Compared to over a dozen existing offshore wind farms built in open waters in China, the distributed offshore wind farm based on energy and transportation can significantly reduce the scope of operations and the area required for construction the sea-area, also lower the impact on shipping in the surrounding area. Furthermore, it is a relatively safe, economic, and environmentally friendly type of offshore wind farm site.   Conclusion  Through discussions on the selection and layout of distributed offshore wind farms based on energy and transportation, the advantages of this type of offshore wind farm, such as reducing the required sea area, minimizing marine obstacles, integrating supply and consumption, and reducing construction and operation costs, are described. This type of offshore wind farm can serve as an important supplement to the current single type of offshore wind farm and become a new type of incremental offshore wind farm site resource in the current stage.
Application of Unified Hardening Model in Soil-Pile Analysis of Offshore Wind Power Large-Diameter Monopiles
MA Zhaorong, LIU Zhentao, WANG Jinxi, ZHANG Youhu
2024, 11(2): 68-81   doi: 10.16516/j.ceec.2024.2.07
[Abstract](109) [FullText HTML](57) [PDF 2609KB](28)
Abstract:
  Introduction  In order to facilitate the design optimisation of foundation for offshore wind turbines, it is necessary to promote application of advanced geotechnical constitutive models that are theoretically sound and capable of modelling realistic soil behaviours in real engineering scenarios.   Method  Firstly, the theoretical framework of the Unified Hardening model (UH model), an advanced constitutive model, was introduced. Then, further modifications oriented to requirements in real engineering applications were presented. Finally, the modified model was applied to the pile-soil analysis of large-diameter monopoles, and the results were analyzed at the macroscopic and element level to verify its effectiveness and practicability.   Result  The UH_G0 model obtained through modification and verification is applicable to addressing issues in real engineering practices. The parameter "initial void ratio" in the original UH model is replaced by "overconsolidation ratio". By incorporating the Andersen empirical formula, the shear modulus is decoupled from the constitutive parameter κ, significantly improving the initial shear stiffness of the original UH model, and thus allowing the UH model to be applicable to the deformation (stiffness) sensitive boundary value problems.   Conclusion  As an advanced constitutive model with a well-defined theoretical framework and physically meaningful parameters, the UH model demonstrates high potential for practical engineering applications. The two modifications tailored to engineering design requirements are necessary, which improve the convenience in application of the UH model to address boundary value problems and the accuracy in calculating initial stiffness, respectively. The modified UH_G0 model is proven to be effective and practical for solving practical engineering problems in the process of finite element simulation.
Research on Bearing Characteristics of Offshore Inclined Helical Pile-Group Foundations in Sandy Soil
YANG Weihua, HU Xueyang, ZHANG Puyang, GAN Yi, CHEN Qingshan
2024, 11(2): 82-92   doi: 10.16516/j.ceec.2024.2.08
[Abstract](64) [FullText HTML](21) [PDF 2809KB](9)
Abstract:
  Introduction  The offshore wind power industry is among the most pioneering and strategic emerging sectors in the global development of new energy sources. The research focuses on the inclined helical pile-group foundation, which is currently applied for offshore wind turbines, and systematically studies its load-bearing characteristics. It is of great significance to accurately understand the load-bearing characteristics for the subsequent popularization of this promising new type of foundation and the overall development of the offshore wind power industry.   Method  The effects of various variables, including pile number, pile spacing and inclination angle, on the bearing characteristics of inclined helical pile groups were systematically studied by finite element software, and the change trends of the pile group effect coefficient and bearing capacity with these factors were obtained under various working conditions.   Result  The results show an approximately 15% improvement in the load carrying capacity of inclined helical pile groups compared to monopoles. Additionally, the efficiency coefficient of pile groups increases with a larger pile number. The load carrying capacity of pile-group foundations is positively correlated with pile spacing, as smaller pile spacing leads to a more significant superposition of central soil pressure. The variation in ultimate load carrying capacity remains within about 4% across the value range of pile spacing. Larger inclination angles enhance the compressive load carrying capacity of inclined helical pile-group foundations, causing an increase in their compression efficiency coefficient. Compressive bearing is found to be effective at an inclination angle of 8°. When subjected to pulling action, the upper soil of inclined helical pile groups experiences less disturbance, the foundations' behavior is more influenced by the pile spacing, and the extreme depth of vertical displacement of the soil at the center of the pile groups gradually decreases with the increase of pile spacing. Conversely, under compressive action, the inclined helical pile-groups exert an influence on the soil in a larger extent, and the interaction effect among piles becomes more stable, without indicating obvious correlation between the extreme depth of vertical displacement of the soil at the center of the pile groups and the pile spacing and inclination angle.   Conclusion  The research results serve to provide certain research approaches and means for the construction of offshore wind power helical pile-group foundations in China, and hold certain reference significance for the dimensional design and bearing capacity evaluation of inclined helical pile-group foundations, demonstrating their value in scientific research and engineering applications.
New Energy Storage
Current Research Status and Development Prospects of Long Duration Energy Storage System
ZHENG Yanchun, SHAN Chaolun, ZHANG Jinbin
2024, 11(2): 93-101   doi: 10.16516/j.ceec.2024.2.09
[Abstract](160) [FullText HTML](53) [PDF 1089KB](44)
Abstract:
  Introduction  Global climate change and its negative impacts are serious humanitarian challenges. Accelerating the construction of a new energy system and promoting energy transition to green and low-carbon are the key to addressing the above challenge. Building a new power system is the central link in planning and constructing a new energy system.   Method  The characteristics and challenges in the six stages of constructing a new power system with new energy source as the main body, and potential roles of energy storage were described and analyzed. The viewpoint that energy storage, especially long-term energy storage, is a key technology for building a new power system was proposed.   Result  To deal with vague concept, unclear technical system and undefined R&D system for long duration energy storage in China, by analyzing the international use cases, the concept system of long-duration energy storage and its technology system covering four categories (including mechanical energy storage, thermal storage, electrochemical energy storage, and chemical energy storage) are proposed. And the R&D trends in developed countries are shown.   Conclusion  It is expected that the relevant content can provide reference for the research and application of long duration energy storage in China.
Research Progress of Liquid Carbon Dioxide Energy Storage System Based on Different Liquefaction Methods
ZHENG Pingyang, HAO Jiahao, CHANG Hong, ZHANG Zhentao, YANG Junling, LI Yanan, ZHANG Jiajun, YUE Yunkai, JING Yanan
2024, 11(2): 102-111   doi: 10.16516/j.ceec.2024.2.10
[Abstract](333) [FullText HTML](125) [PDF 2186KB](78)
Abstract:
  Introduction  With the large-scale application of new energy, the challenges faced by the grid connection of new energy power generation are growing, and the importance of energy storage system is increasing. carbon dioxide energy storage (CES) technology is a kind of compressed gas energy storage technology emerging in recent years, with the advantages of high energy storage density, long service life and high design flexibility. For liquid carbon dioxide energy storage (LCES) technology, CO2 is stored as liquid phase in both HP and LP sides of the system, which has high energy storage density and strong operation stability.   Method  Firstly, the operation principle and key technical indicators of the LCES system was introduced and the importance of carbon dioxide liquefaction and common liquefaction processes were clarified. Then, the research status of CO2 liquefaction on the LP side of the LCES system was introduced, including the use of mixed energy storage working medium, self-condensation, the LNG cold energy, and the regenerator. The characteristics of each method were analyzed in detail.   Result  The research indicates that the application of regenerator is the most effective method. It is necessary to further analyze the challenges faced by current cold storage liquefaction technology and its development direction.   Conclusion  The research could provide guidance for the further development of CO2 liquefaction technology for the LCES system.
Thermodynamic Analysis of Highview Power's Liquid Air Energy Storage Pilot Plant
SUN Xiao, CAI Chunrong, LUO Zhibin, WANG Xiaobo, ZHU Guangtao, PEI Aiguo
2024, 11(2): 112-124   doi: 10.16516/j.ceec.2024.2.11
[Abstract](65) [FullText HTML](36) [PDF 2181KB](11)
Abstract:
  Introduction  Energy storage technology becomes an essential supporting technology to build a new power system with renewable energy as the main power source. Liquid air energy storage (LAES) is one of the emerging large-scale energy storage solutions, which is technically and economically feasible and has a wide range of application prospects. The pilot plant built by Highview Power is the only LAES for which test data have been made public. The paper aims to explore the thermodynamic principle of LAES and seek ways to improve the cycle efficiency of LAES.   Method  A thermodynamic model was established according to the process flow of Highview Power's pilot plant. The thermodynamic model was verified by the test data of the pilot plant. Exergy analysis was carried out. The influence of key operating parameters on the charging and discharging process was studied by the control variable method.   Result  The results show that the key equipment limiting the cycle efficiency are recycle compressor and evaporator. Increasing the compression pressure and post-throttling pressure, increasing the mass flow rate and inlet temperature of the cryogenic expander, and recovering the cooling capacity of the regenerator are beneficial to improving the liquefaction rate and reducing the energy consumption of liquefaction. Moreover, increasing the high pressure and the inlet temperature of turbine expansion unit can help to improve the output power and cycle efficiency of LAES.   Conclusion  Some improvement measures are put forward to improve cycle efficiency, such as recovery of compression heat, improvement of compressor isentropic efficiency and reduction of heat transfer temperature difference of evaporator.
Optimization Strategy for Collaborative Frequency Modulation of PVs-ESs Based on MPC
YAN Xiaoshan, TANG Huiling, WU Jiekang, ZHOU Zhiting, LONG Yongcheng, FENG Guohua
2024, 11(2): 125-138   doi: 10.16516/j.ceec.2024.2.12
[Abstract](43) [FullText HTML](28) [PDF 3784KB](15)
Abstract:
  Introduction  In order to reduce frequency disturbance caused by photovoltaic (PV) generation to power grid and further improve the frequency modulation effect, an optimization strategy for collaborative frequency modulation of PVs-ESs based on MPC (Model Predictive Control) is proposed. The basic principles, control flow, constraints, target function and weight coefficient of the strategy are analyzed.   Method  A model of optical-storage network based on MPC was constructed and the nonlinear state space equation was derived. In order to verify the frequency modulation effect of this strategy, four different simulation environments were set up: no energy storage, battery storage, mixed energy storage and the strategy proposed in this paper.   Result  Simulation results show that compared with other scenarios, the proposed strategy is optimal in terms of frequency modulation and the worst in the absence of energy storage. In addition, the hybrid energy storage method is superior to the battery energy storage method.   Conclusion  The effectiveness of the proposed strategy is validated on the MATLLAB/Simulink platform. In photovoltaic power generation system, optimal control of energy storage and PV maximum power point tracking can make the grid frequency more stable and improve the stability of the whole system. The results of this study can be used as a reference for PV connection.
Influence of Service Conditions on Electrochemical Performanceof Lithium-Ion Batteries
XIN Tian, GAO Xiaotian, XIAO Kai, LUO Zhibin, HUANG Zhaohe, ZHANG Naiqing
2024, 11(2): 139-145   doi: 10.16516/j.ceec.2024.2.13
[Abstract](66) [FullText HTML](22) [PDF 1309KB](19)
Abstract:
  Introduction  Lithium-ion battery has become the most widely used new energy storage technology. However, it is found that the practical service conditions have great impacts on the actual service behaviors of lithium-ion battery energy storage. This paper aims to study the influence of service conditions on the electrochemical performance of lithium-ion battery, so as to provide references for the construction of future lithium-ion battery energy storage projects.   Method  The effects of operating charge interval, discharge rate and operating temperature on the actual performance of Li-ion battery were tested and analyzed.   Result  The working SOC range, charge/discharge rage and operating temperature all have great influence on the actual performance of lithium-ion battery. On the one hand, proper adjustment of charge and discharge range can significantly improve the service life. On the other hand, the current commonly used 2 C configuration mode may significantly reduce the service life, while reducing the rete configuration to 1 C is expected to achieve lower levelized cost of energy although it will increase the initial investment. In addition, temperature control is extremely important to the usage of lithium-ion batteries, even single-digit temperature differences can cause significant battery inconformity over long cycle life.   Conclusion  Lithium-ion battery energy storage with advantages of fast response speed, high adjustment accuracy and flexible configuration will further play an important role in the work of "carbon peak and neutrality" and the gradual construction of the power market. Paying attention to the influence of practical conditions on the performance of lithium-ion battery will further improve the use efficiency of lithium-ion battery energy storage. In summary, the design of the battery working condition according to the demand of the practical application can provide lithium-ion battery energy storage system more excellent performance, and play an important role to realize the "carbon peak and neutrality" goal of our country.
Research Status and Development Trend of Compressed Air Energy Storage Technology
YUAN Zhaowei, YANG Yifan
2024, 11(2): 146-153   doi: 10.16516/j.ceec.2024.2.14
[Abstract](229) [FullText HTML](44) [PDF 969KB](45)
Abstract:
  Introduction  Compressed air energy storage (CAES), as a long-term energy storage, has the advantages of large-scale energy storage capacity, higher safety, longer service life, economic and environmental protection, and shorter construction cycle, making it a future energy storage technology comparable to pumped storage and becoming a key direction for future energy storage layout. By summarizing the current status of CAES technology, the working principles, challenges, and solutions of different CAES technologies are analyzed, which is provided for the development of CAES technology through research.   Method  Firstly, the principle of CAES was introduced, the key equipment, such as compressors, turbo-expanders, and heat exchangers, was analyzed, and the key equipment suitable for the CAES was proposed. Then, the commonly used key technologies, development trends, and engineering cases of large-scale CAES were introduced from the perspective of ground key process technologies and underground gas storage facilities. Finally, the future development trend of CAES technology was analyzed.   Result  The results show that regenerative CAES is currently the mainstream technology in China, and high-temperature heat storage has become the future development direction of CAES, and is also an important way to improve the efficiency of CAES. At the same time, there is still room for improvement in key equipment and technology optimization, cost reduction, and application scenario development of the system.   Conclusions  CAES, as a long-term energy storage method, plays an important supporting role in the construction of future new power systems.
An Energy Storage System with Binary Cycle Gas Compressionand Its Feasibility Analysis
ZHENG Kaiyun, CHI Jiecheng, ZHANG Xuefeng
2024, 11(2): 154-161   doi: 10.16516/j.ceec.2024.2.15
[Abstract](69) [FullText HTML](28) [PDF 910KB](19)
Abstract:
  Introduction  The compressed air energy storage system has a very large air storage volume and high pressure, and usually uses the underground salt cavern as the gas storehouse. Project development is constrained by scarce salt cavern resources. The compressed carbon dioxide energy storage system uses the storage tank with the atmospheric flexible gas film to store carbon dioxide gas. The gas film tank has a huge volume and occupies an excessive area, making it difficult to meet the requirements of construction land indicators of the industrial park. In order to achieve the widespread application of the energy storage with gas compression in industrial parks, an energy storage system with binary cycle gas compression is proposed.   Method  The system integrated the compressed air energy storage and compressed carbon dioxide energy storage systems, and utilized a shared gas storehouse. The gas storehouse adopted specially designed pressure vessels, which were divided into equal-pressure and scalable air chambers and carbon dioxide chambers using flexible membranes. The system could achieve the storage and release of energies through the collaborative work of compressed air circuits and compressed carbon dioxide circuits, while maintaining a constant-pressure operation in the gas storehouse. In order to evaluate the energy storage performance and energy storage density of the system, a preliminary thermodynamic calculation was conducted on the 100 MW/400 MWh energy storage system of the ground gas storehouse with a storage pressure of 3 MPa, followed by an analysis of the engineering feasibility.   Result  The results show that the energy storage efficiency of the system is 70.20% and energy density is 3.85 kWh/m3. The system is suitable for supporting energy storage in industrial parks and can provide the multi-generation function of electricity, gas, cooling and heating. Compared to electrochemical energy storage, it has significant commercial competitive advantages.   Conclusion  For energy storage scenarios in industrial parks, the energy storage with binary cycle gas compression has an important potential commercial value due to its flexible location selection, feasible technology, mature equipment, and controllable cost.
Hydrogen Technology
Development Status and Outlook of Hydrogen Powered Fuel Cell Vehicle Market in China
LIU Chang, LIN Hanchen, SHI Chenfangda, HU Mingyue
2024, 11(2): 162-171   doi: 10.16516/j.ceec.2024.2.16
[Abstract](273) [FullText HTML](699) [PDF 2259KB](81)
Abstract:
  Introduction  As one of the main tracks of hydrogen energy development, fuel cell vehicle industry plays a key role in the process of transportation decarbonization. In view of the current policy environment and industrial base, it is necessary to systematically analyze the development trend and challenges of China's fuel cell vehicle market.   Method  A comprehensive discussion of the fuel cell vehicle market focusing on the market factors such as market size, segmentation direction, equipment and hydrogen source price, etc. was provided in this paper.   Result  The promotion and application effect of China's fuel cell vehicle market is closely related to the strength of policy support, the clarity of the detailed rules of subsidies and the driving force of local advantageous enterprises. In terms of market distribution, it has shown a certain leader effect according to the comprehensive competitiveness of vehicle and fuel cell enterprises. The price of the vehicle and the fuel cell power system has decreased by 5%~20% compared to 2021, but it still costs a lot in application.   Conclusion  Although China's fuel cell vehicle marketization is still hampered by the high manufacturing cost and hydrogen price, and the lack of infrastructures, but the fuel cell vehicle industry will show great vitality after further developed in performance verification, infrastructure construction and business structure innovation.
Analysis of the Impact of Water Resources on China's Green Hydrogen Industry
ZHANG Mingzhen, ZHANG Can, WU Xiushan, CHENG Qian
2024, 11(2): 172-178   doi: 10.16516/j.ceec.2024.2.17
[Abstract](141) [FullText HTML](70) [PDF 1667KB](26)
Abstract:
  Introduction  The purpose of this paper is to research and analyze the influence of water resources on the development of the green hydrogen industry in China, reveal the contradiction between water resources and the development of green hydrogen industry, analyze the future development trend of the green hydrogen industry and to provide useful reference for the development layout of renewable energy hydrogen production projects in China.   Method  In order to prove that water resources could limit the development of the green hydrogen industry in "Northeast China, North China, Northwest China" and other areas, the analysis and the demonstration were made based on the field investigations and the documentary materials, considering water resources policies, water usage in traditional chemical industries, and hydrogen production technologies.   Result  The analysis results show that under the restriction of China's water resources-related policies, the layout of green hydrogen industry should consider the constraints of water resources, and the large-scale production of green hydrogen and its substitution for fossil energy hydrogen production cannot effectively save water. Instead, it may lead to an increase in water consumption by the chemical industry. Under the constraint of water resources, the development of China's green hydrogen industry must consider the layout from a holistic perspective, fully integrate the development trend of the existing chemical industry, and consider the abundant resources available such as seawater.   Conclusion  The development of the green hydrogen industry in China should not ignore the problems of existing policy framework, technology level, industrial layout and characteristics of existing resources. When arranging the layout of the green hydrogen projects, the current situation and future trends should be fully considered, and the problems posed by water resources on the green hydrogen industry should be solved from the perspective of the overall planning, the coordinated industrial development and the effective utilization of resources.
Energy Economy
Analysis on Regional Difference of the Whole PV Industry Chain from the Perspective of Policy
HUANG Bin, ZHAO Wei, LIAO Lida, XIAO Meng, HUANG Jialiang, XIE Peiling
2024, 11(2): 179-188   doi: 10.16516/j.ceec.2024.2.18
[Abstract](147) [FullText HTML](84) [PDF 2850KB](34)
Abstract:
  Introduction  The "carbon peak and neutrality" strategy has put forward a new path for China's energy development, which restricts the use of traditional fossil energy, and promotes the Chinese government to increase its support for the development of the new energy industry. Photovoltaic, as a new energy which is the most accessible and has the widest coverage, has become the first choice to solve the current energy and environmental problems. However, if we want to increase its market scale and realize the vigorous development of photovoltaic industry, it is necessary to find out and solve the pain points and difficulties of the current stage.   Method  China's policy on the whole photovoltaic industry chain was combed and analyzed to explore the shortcomings of the photovoltaic industry incentive policy. Based on the data from 33 sample enterprises in the A-share market from 2000 to 2021, the DEA model was built and the integrated innovation benefits and scale benefits of China's PV industry under the guidance of policy were explored. And using the panel regression analysis method, the different impacts of different regional policies on the innovation capacity of the upstream, middle and downstream enterprises of the PV industry. were explored.   Result  The research shows that the policy subsidies have a more significant impact on the innovation benefits of upstream photovoltaic enterprises, which is positively correlated with the development of enterprises in the eastern region. While in the western region, the opposite is the case, and there are certain regional differences.   Conclusion  It is necessary to improve the preferential policy strength in the photovoltaic technology innovation level, and carry out a reasonable industry chain planning and layout in combination with the regional advantages.
Empirical Research on the Evolution of Relationship Between Energy and Economic Development in Guangdong
WU Dongqi, GAN Junwen, GUO Jingtao, YU Xinmei, LIAO Yi
2024, 11(2): 189-197   doi: 10.16516/j.ceec.2024.2.19
[Abstract](47) [FullText HTML](28) [PDF 2090KB](7)
Abstract:
  Introduction  Since the initiation of China's "reform and opening up" policy in 1978, Guangdong Province has achieved significant progress in economic growth and energy sector development. The provincial economy has shifted from rapid growth to emphasizing high-quality development. In the face of profound changes unseen in a century around the world and the imminent need to achieve "carbon peak and neutrality" goals, as well as industrial transformation and upgrading, the underlying relationship between energy consumption and economic development has gradually evolved in Guangdong. Therefore, a comprehensive understanding of this new relationship serves as a theoretical grounding for the allotment of resources and utilization of opportunities arising under the "carbon peak and neutrality" goals, which is indispensable to facilitating high-quality and coordinated development in the energy sector and economy development.   Method  A quantitative analysis of the relationship between energy consumption and economic growth in different development stages of Guangzhou since 1987 was presented, using representative energy and economic indicators and through the Granger causality test.   Result  The results reveal that the relationship between energy consumption and economic growth in Guangdong is not statistically consistent throughout the entire period from 1987 until now. However, economic development became a significant Granger cause for the surge in energy consumption after Guangdong entered its middle and later stage of industrialization in the mid-90s.   Conclusion  Guangdong has experienced a changing relationship between energy and economy in its different stages of development since 1987. The rapid growth of the manufacturing sector has stimulated the growth in energy consumption, exhibiting a distinct characteristic of demand-driven growth.
Energy Material
Full-Spectrum Carbon-Based Ceramic Fibers and Their Application in Seawater Desalination
QIU Xiaopan, XI Yulin, ZHU Jingshuai
2024, 11(2): 198-207   doi: 10.16516/j.ceec.2024.2.20
[Abstract](55) [FullText HTML](30) [PDF 3189KB](16)
Abstract:
  Introduction  An environmentally friendly technology that harnesses green renewable solar energy to generate thermal energy for seawater desalination is proposed and the design of a novel fibrous membrane evaporator with full-spectrum absorption capability is introduced, aiming to address global challenges such as environmental pollution and freshwater scarcity.   Method  The proposed technological process began with the preparation of nano-scale C@TiO2 fibrous membranes using the electrospinning process. These membranes then underwent in-situ carbothermal reduction at 800 ℃ for 2 hours, resulting in the production of carbon-based ceramic C@Ti4O7 photothermal conversion materials with a dark color.   Result  The results show that the C@Ti4O7 fibrous membrane exhibits a band gap much lower than that of W-TiO2 and excellent solar light absorption capability across a wide range of wavelengths from 200 to 2500 nm, due to the doping of C elements and Ti3+ and the presence of oxygen vacancy defects. Under a light intensity of 1 kW/m2, the surface temperature of the C@Ti4O7 fibrous membrane, floating at the air-seawater interface, can quickly rise to 74.55 °C. Consequently, the evaporation rate of seawater increases to 1.55 kg/(m2·h), resulting in a photothermal conversion efficiency as high as 90.68%. With a light intensity of 5 kW/m2, the evaporator can generate electrical signals of up to 460 mV. In addition, it is proven workable continuously for 30 days in the simulated seawater with NaCl mass fraction of 10%, without salt deposition on the surface.   Conclusion  Therefore, the adoption of carbon-based ceramic C@Ti4O7 as the photothermal conversion material for the solar-driven interfacial evaporator offers not only high efficiency in photothermal conversion, but also great potential for large-scale applications, demonstrating a broad application prospect in the field of seawater desalination.

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