Ebook: Green Energy, Environment and Sustainable Development

The 4th International Conference on Green Energy, Environment and Sustainable Development (GEESD2023) was successfully held from 15–17 June 2023, face-to-face in Mianyang, China and online via Zoom. About 70 attendees participated in the conference, which was divided into three parts: keynote sessions (each of 30 minutes), 22 oral presentations (each of 15 minutes), and 10 poster presentations.

Special thanks go to the following keynote speakers for their excellent speeches:

Professor Mohammadreza Aghaei, from the Norwegian University of Science and Technology (NTNU), Norway

Professor Yifei Wang, from the Harbin Institute of Technology, China

Professor Wending Pan, from the University of Hong Kong, Hong Kong, China

Professor Tsair-Wang Chung, from Chung-Yuan Christian University, Taiwan, China

Professor Richao Cong, from the University of Kitakyushu, Japan

The session chairs and keynote speakers worked together to select the best oral presentation and poster presentation.

This collection is divided into seven sections: (1) Green Energy and Systems; (2) Computer Methods in Environment; (3) Chemistry and Environment; (4) Ecology and Rural Environment; (5) Energy, Environment and Economy; (6) Environment and Pollution; and (7) Water and Mineral Resources, with the most up-to-date findings and technologies being discussed. We believe participants in GEESD2023 will have both gained knowledge and had the opportunity to meet new friends in the same fields, and we hope that this collection will benefit readers in the same way.

Yingfa Lu

Hubei University of Technology, China

To support regional decarbonization, this study focuses on designing an optimal green energy management system in which renewable energy (onshore, offshore wind power, solar power, and biomass power) are made as prioritized sources to meet the temporal energy demand. The optimization algorithm is applied in the Kitakyushu City of Japan. At first, the annual renewable energy supply and energy demand were estimated and disaggregated to an hourly level, considering the temporal patterns. The storage battery is introduced to rebalance the supply and demand sides. Through its control, the surplus of balance between renewable energy and demand is stored by the battery without supplying from grid power. Meanwhile, the grid power is only supplied when the total green energy supply is less than the demand. The minimum carbon dioxide (CO₂) emission is defined as the objective function. The constraints are considered as including the battery capacity, charging and discharging balance, hourly and annual supply potential for each type of energy, and hourly supply should meet the demand. As our solution, 99.9% of onshore wind power, 56.8% of offshore wind power, 69.8% of solar power, and 45.4% of biomass power were essential in a year to meet each hourly demand and achieve the minimum CO₂ emissions.

Over the past few years, there has been a substantial increase in attention and notable interest in the utilization of solar energy for agricultural applications. This increased attention stems from the recognition of solar energy as a compelling and environmentally conscious alternative to conventional energy sources. Among the various applications, solar drying of crops has emerged as a promising method for preserving agricultural produce while minimizing energy consumption and reducing carbon emissions. In this study, our objective is to assess the thermo-economic and ecological performance of a solar-electric hybrid greenhouse dryer specifically designed for grape drying. The proposed system integrates solar collectors, an electric heater, and a greenhouse structure to create a controlled and energy-efficient environment for grape drying. The assessment includes a thorough analysis of the thermal performance, energy consumption, and cost-effectiveness of the solar-electric hybrid greenhouse dryer. Additionally, an ecological assessment is performed to assess the environmental impact of the system, considering factors such as carbon emissions and sustainability. The findings of this study are expected to have a significant impact on the advancement of sustainable agricultural practices and the widespread adoption of renewable energy technologies in the field of food production. Moreover, the obtained results serve as valuable insights for designing and optimizing similar solar drying systems intended for different crops and geographical regions. By considering specific crop characteristics and local environmental conditions, researchers and engineers can develop efficient and customized solar drying solutions. This knowledge will ultimately enhance the effectiveness and applicability of solar drying technologies, facilitating sustainable agricultural practices across diverse contexts.

Hybrid stepper motors (HSMs) have a wide range of applications. However, conventional open-loop control is difficult to meet the demand for higher accuracy. The development of control theory and electronic technology makes the application of advanced control techniques possible, including model predictive control (MPC). In this paper, a stepper motor current loop predictive model has been constructed, and then the design of q-axis current regulator has been implemented by feedback correction and rolling optimization, which has been applied to the field-oriented control (FOC) of stepper motor and verified by simulation and experiments. The results indicate that the MPC regulator in this paper has good regulation effect and reduces the q-axis current ripples to a certain extent in the series control, which finally improves the control performance.

In WPT-MRC (Wireless Power Transfer via Magnetic Resonance Coupling) systems, the resonator coils need to be aligned for maximum efficiency, and any misalignment between resonator coils can result in a significant drop in output efficiency. Therefore, improving the anti-misalignment capability of WPT systems is an important consideration for practical applications. The paper has proposed a NUDCT (Non-Uniformly Distributed Coil Turns) coupler with uneven turns that generates a uniform magnetic field to improve anti-misalignment capability of WPT-MRC systems. The proposed NUDCT resonator has been optimized using GA (Genetic Algorithm), and the theoretical analysis of the magnetic field in case of misalignment has been presented. The paper has also validated the WPT-MRC system’s transmission performance using the optimized coil. The results indicate that the magnetic field generated by NUDCT provides better uniformity under misalignment and higher system efficiency.

A stable slope is a crucial factor for water reservoir in a hydropower station regarding power generation. This paper mainly uses FLAC3D to analyze the slope stability and excavation with reinforcement support of stilling basin on the left bank of Kala Hydropower station regarding different operation cases. The numerical analysis reveals that the slope stability meets the design specification of class A and II slopes, while the potential instability area is mainly located in fragmented structural rock mass and class IV rock mass. After the excavation and reinforcement, the stability of the slope is improved to a certain extent, and Sericitolited Sand Slate is located at the foot of the slope, which basically has no effect on the slope stability. The slope unloading and toppling deformation of the left bank regarding the engineering area is obvious, and the shallow surface rock mass is prone to relaxation and damage during the slope excavation process. Therefore, it is recommended that the support should be on time, and according to the geological situation revealed, appropriate reinforcement treatment can be taken to ensure the safety and stability of the construction period. Sericitolited Sand Slate has a certain range of exposure during the excavation process, resulting in slightly higher slope deformation, so it should be carefully excavated. The slate is easy to soften when exposed to water, so attention should be paid to the timeliness and effectiveness of drainage measures during the construction period to avoid local collapse damage caused by softening of rock mass.

In the field test of tidal energy converters, the measurement of tidal current velocity is one of the key steps to evaluate the power characteristics performance of tidal energy converter. According to the requirements of tidal current velocity measurement specified by the International Electrotechnical Commission, tidal current velocity field measurement work was carried out, and the tidal current field measurement data was processed and analyzed by using the method proposed in this paper, which combines the elaborated division of tidal current velocity bine with standard deviation and correlation coefficient. The results show that: During the flood tide period, there is little difference in the mean value of tidal current velocity between the two measuring locations, but the tidal current velocity measured at the RTI location fluctuates greatly; During the ebb tide period, the mean value of tidal current velocity at the two measuring locations is quite different, and the tidal current velocity that measured at the RTI location also fluctuates greatly; The duration of the flood tide is shorter than that of the ebb tide, but the maximum value of tidal current velocity of the flood tide is greater than that of the ebb tide.

With the adoption of “Carbon peak and carbon neutrality” in China, parabolic trough solar collectors have attracted considerable research attention. This study proposed an experimental system scheme based on a system to test the thermal performance of PTSHCS s in Lhasa. Furthermore, a series of experimental studies were conducted on the system which is used to test the collectors’ thermal performance in the plateau environment. The actual operation data of the collector under typical weather conditions was collected, and the collector’s thermal performance in plateau environment was analyzed. The results revealed that the solar radiation intensity, the temperature of the oil at the inlet of metal collector tube, and the flow rate of the oil to transfer heat were closely related to the heat collection efficiency of PTSHCS. A strong positive correlation exists between the solar radiation intensity and the thermal efficiency of the collector. When the rate of the fluid to transfer heat increased from 5m³/h to 7m³/h, the thermal efficiency of the collector increased significantly, and the maximum instantaneous thermal efficiency reached 66%. When the inlet temperature of the oil used to transfer heat increased from 80°C to 170°C, the thermal performance exhibited a general downward trend.

The corrosion products in the secondary circuit of the nuclear power plant continuously accumulate and are deposited on the steam generator (SG) secondary side, which will have a great impact on the safe and economic operation of the nuclear power plant. Although the deposits thickness of a CPR1000 unit is relatively low, it has seriously reduced the heat transfer performance of the tube bundle. Based on the SG heat transfer calculation model and the matching margin of steam generator and steam turbine, a normalized SG thermal performance monitoring and evaluation model of CPR1000 unit is established. Based on the actual operation data of a CPR1000 unit, the corresponding treatment measures and suggestions are put forward. This model can predict the subsequent operation trend of SG, so as to increase the safety and economy of nuclear power plants.

In the process of converting lignocellulose to biofuels, lignin is one of the major obstacles. To overcome this recalcitrance, exploring bacteria with higher delignification efficiency or novel enzymes has been highlighted. In this study, eight bacteria isolated from termite guts were evaluated for their lignolytic potential. Among the isolates, Raoultella ornithinolytica MP-132 was selected for further investigation based on its capacity to use a broad range of monomeric and dimeric aromatic compounds as carbon source. Subsequently, the structural evolution of milled wood lignin (MWL) was evaluated by FTIR and TGA. The analysis results showed the cleavage of various chemical linkages, destruction of aromatic ring structures, side-chain oxidation and demethoxylation or demethylation by comparing the different peak intensities in the corresponding curve of each sample. In addition, the thermal stability of MWL increased after bacteria treatment, indicating the structural change in MWL caused by treatment with strain MP-132. These results demonstrated that Raoultella ornithinolytica MP-132 may be a potential candidate for the lignocellulosic bioenergy industry.

In the development and construction of offshore wind farms, it is essential to consider various factors such as wind energy resources, hydrogeology, grid-connected conditions, transportation, construction and installation, socio-economic environment, and ecological protection. Additionally, the meteorological conditions at sea should also be evaluated. This study aims to evaluate the situation of offshore wind energy and wind resources in Hangzhou Bay. The evaluation was conducted based on the relevant methods in the “Wind Farm Wind Energy Resource Evaluation Method” and the “National Wind Energy Resource Evaluation Technical Regulations”. The analysis was carried out using meteorological observation data and ERA5 reanalysis data. Through the analysis of WS, average wind power density, representative annual wind energy resource analysis, and maximum WS during the reproduction period of meteorological stations indicate that the sea area is rich in wind energy resources. The main wind direction is consistent with the main wind direction, which is conducive to fan arrangement.

To calculate the proportion of evaporative emissions of the China VI, this paper establishes a single-vehicle evaporative emission model for light gasoline vehicles, and an activity level model based on the car use habits of the employees of China Automotive Technology Research Center Co., Ltd. The proportion of evaporative emissions from Vehicle-A and Vehicle B, the running loss emissions of both Vehicle-A and Vehicle B account for over 50%, while refueling emissions and the diurnal 48-hour emissions account for lower proportions. The total annual evaporative emissions of vehicle A can reach 353.496 g, and the total annual evaporative emissions of vehicle B can reach 589.758 g.

Accurate estimation of the lithium-ion batteries (LiBs) state of health (SOH) is vital for ensuring the safety and dependability of electric vehicles (EVs) throughout their life cycle. However, the traditional neural network estimation has low fitting accuracy, and most research in this field is based solely on normal temperature states. To address this, we propose extracting health factors (HFs) from battery data under different temperature states, employing the Gaussian process regression algorithm (GPR) to estimate SOH. We also examine the influence of various kernel functions on the estimation results of the GPR algorithm.

In recent years, the eutrophication in the typical tributaries of the Three Gorges Reservoir has attracted widespread attention. In the present paper, three typical eutrophic tributaries in the Three Gorges Reservoir area, that is, Xiaojiang River (Pengxi River), Daning River and Xiangxi River, were selected for research, and a two-dimensional hydrodynamic and water quality coupling model that is for the area from Zhutuo to dam site was constructed by using MIKE 21 software. On this basis, the temporal and spatial distribution of pollutants in three tributaries in 2021 was further simulated and analyzed. The results showed that: (1) The coupling model after calibration and validation had good simulation accuracy for hydrodynamic and water quality indexes in the reservoir area, and the simulation effect was in good agreement with the measured results; (2) The concentration of each pollutant was closely related to the change of water level and water quantity. From the highstand period to the pre-discharge stage (January-June), the concentrations of total nitrogen and total phosphorus increased, which were very high from the post-discharge period to the lowstand period (July-September); (3) The concentration of pollutants in the confluence of the main stream and tributaries was high due to the backward flow of the main stream. To sum up, the higher concentration of pollutants and the higher water temperature in spring and summer were conducive to the rapid reproduction of algae and other plankton, resulting in eutrophication, and the algal bloom was easy to break out in the reservoir area. During the water storage period and highstand period (October-December), the concentrations of total nitrogen and total phosphorus showed a downward trend, mainly due to the self-purification of water and the degradation of pollutants. The research conclusion can provide a reference for water quality evaluation, water supply safety and pollutant treatment in the Three Gorges Reservoir area.

According to the idea of fuzzy reliability evaluation of foundation engineering, the attenuation model of foundation resistance with time is established by introducing the evolution model of important parameters with time in the limit state of foundation engineering. On this basis, the attenuation law of reliability with time is found and the remaining service life is determined according to the specified threshold of reliability decline. Based on a specific engineering case, the remaining service life is calculated to verify the rationality of the proposed method.

A wind tower with five 3-dimensional-ultrasonic anemometers observed the wind field information of typhoon Soulik 0n 15 m, 27 m, 53 m, 67 m, and 82 m respectively. The wind tower was located in Ningde, Fujian Province. In this research, the variation of gust factor and turbulence intensity over time was studied. The results show that the equation for the relationship between gust factor and turbulence intensity was fitted. Finally, the variation of the crest factor with time was studied and compared with empirical equations. It was found that under the condition of low wind speed, the crest factor at a specific time interval is greater than the research of Durst. When the wind speed is relatively high and the time interval is small, the measured value is less than the research of Durst. As the time interval increases, the measured value gradually exceeds the result.

With the continuous maturity of tidal current power generation technology, the scientific requirements for testing and evaluation are also increasing. In the process of analyzing the measured power data of tidal current power generation, the selection of sampling interval has a significant impact on the accuracy of power fluctuation analysis. Choosing an appropriate sampling interval can reduce data processing and improve calculation speed while ensuring the accuracy of test data. Based on the measured power data of tidal current power generation in a certain sea area of China during rising and falling tides, this paper calculated and analyzed the power fluctuation of multiple sampling intervals through discrete index analysis and first-order difference component analysis. And based on the entropy weight method, obtained the regularity of power fluctuation with sampling interval, calculated the comprehensive fluctuation coefficient to determine the maximum sampling interval, and proposed a recommended sampling interval of 60 seconds. This has important practical significance for scientifically testing tidal current power generation.

At present, the nuclear power plants built and under construction in China are all coastal nuclear power plants, and the Essential Service Water System (SEC) and Circulating Water System (CRF) are all once-through cooling systems. If these systems are directly applied to the inland sites, the following problems will be leaded: safety functions could hardly be guaranteed, high construction costs, and significant environmental impacts, etc. Based on the circulating cooling technique, this paper proposes improved schemes of SEC and CRF systems by equipping them with safe mechanical ventilation cooling towers, safety water storage pools, and large natural ventilation cooling towers. The improved SEC system ensures the implementation of long-term safety functions and reduces construction costs. The improved CRF system can reduce water intake by 97% and significantly reduce environmental impact. The improved cooling chain systems proposed in this paper provide a reference for the cooling chain system design of inland nuclear power plants.

Sub-criticality monitoring under post-accident conditions is of great significance for emergency operations in nuclear power plants, as many post-accident physical phenomena may disturb the measurement process of neutron flux outside the reactor, how to quantitatively evaluate the disturbances is therefore becoming a key issue for core reactivity monitoring in post-accident conditions. In this paper, the Monte Carlo model is established based on the actual neutron diffusion process to quantitatively evaluate the disturbance to neutron flux measurement outside the reactor considering the following post-accident physical phenomena: group (N-1) control rod assembly dropped after shutdown, reactor cavity flooding, core cavitation, core draining. The amplification and attenuation factors due to these physical phenomena are obtained, based on which proposals are suggested to realize an accurate diagnosis of the core sub-criticality state and to prioritize the nuclear power control in post-accident conditions, this is essential for operating strategy orientation and fuel clad barrier integrity control in the emergency operation of nuclear power plants.

During the erection of multi-bundle conductors of transmission lines, spacers shall be installed between conductors to ensure that the equivalent radius between conductors meets the requirements of relevant standards. During the existing construction process, the installation position of the spacer is marked manually. When marking, only the installation position of the spacer for a single conductor is marked, and the installation posture of the spacer cannot be guaranteed. In this paper, the four-bundle conductor is taken as an example to study the above problems. The studied marking mechanism can ensure that each sub-conductor on the four-bundle conductor has a mark, and the installation position of the spacer is more accurate. The research on the marking mechanism is mainly aimed at its structural stability, installation convenience, marking effect and identifiability, which effectively solves the on-site construction problems.

The reliability analysis and calculation of the electrical main wiring is not only the core content of the electrical design of pumped storage power stations, but also provides a theoretical basis for the selection of the electrical main wiring of pumped storage power stations. This paper considers pumped storage power plants as a whole, taking into account the reliability model of relay protection devices and random faults of various components. When establishing a reliability indicator system, this paper considers two operating conditions: power generation and pumping. The proposed model and algorithm are verified and calculated according to a concrete engineering case.

Based on the initial design of 64 groups of refueling assembly at Haiyang Nuclear Power Plant (HNPP), a long-term refueling management strategy (RMS) study was conducted using the COSINE software package, and a refueling management plan for 92 groups of new fuel assembly was designed. On this basis, simulation calculations were conducted on the main core parameters of the 3rd to 8th cycles, and universal design limits were verified. The simulation calculation results show that HNPP has the refueling capability of 92 new fuel assembly, and the designed refueling plan satisfies the design limits and requirements.

This article proposes a design scheme for an automatic battery swapping station for electric vehicles. The automatic battery swapping station mainly includes a cyclic battery pack storage device, a battery pack storage compartment, a swapping platform and so on. The cyclic battery pack storage device has a battery life processor, and the battery pack storage compartment reads the usage curve data of each battery through an interface. The battery life processor collects data on the temperature and current of the battery during electric vehicle driving and establishes a capacity degradation model for non-linear Wiener processes. It calculates the lifespan of the battery pack, sorts the batteries, sets the priority of each battery, and ultimately places the battery with the highest priority at the top of the battery swap queue. The swapping platform can automatically disassemble and assemble the battery pack when it reaches the designated position. The automatic battery-swapping station can lift and stack the battery packs without complex lifting mechanisms, making the swapping process simple, the battery pack exchange time short, and the swapping efficiency high.

According to the cracking of steam pressure sampling tube at the inlet of high pressure cylinder of an ultra-supercritical unit in a thermal power plant, the cracking mechanism of steam pressure sampling tube was studied by means of macroscopic inspection, metallographic test, hardness inspection, room temperature tensile test and SEM test. The results indicate that the inner wall microstructure of the cracked steam pressure sampling tube is stratified, and the microhardness of the core is higher than the standard requirement. There are many spot-like or strip-like endogenous inclusions in the sample core, so it can be determined that the principal reason for the cracking of steam pressure sampling pipe is the poor manufacturing quality of the pipe.