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With the increasing number of electric vehicles (EVs), a large amount of charging load will affect the safety and economic operation of the distribution network (DN). In this paper, an optimization dispatching strategy for integrated electricity and natural gas systems (IEGS) with fast charging stations (FCSs) is proposed to address the impact of fast charging loads. Firstly, the FCS load model is established based on the simulation of vehicle traveling and vehicle charging. Secondly, a natural gas supply model is established, which includes constraints such as the adjustment range, direction, and total number of supply flow adjustments. Then, an optimization dispatching strategy for IEGS based on energy storage and gas storage is proposed. Finally, the effectiveness of the proposed strategy is verified. The simulation results show that when the proposed strategy is applied, the voltage of FCS node will be stabilized within a good range. And the energy purchase cost will be reduced by more than 50%. The proposed method improves the carrying capacity of DN for FCSs. [ABSTRACT FROM AUTHOR]

This article presents a study on the distributed optimization operation method for micro-energy grid clusters within an electric, thermal, and hydrogen integrated energy system. The research focuses on precisely modeling the Power-to-Hydrogen (P2H) conversion process in electrolytic cells by considering their startup characteristics. An optimization operation model is established, with each micro-energy grid as the principal entity, to cater to their individual interests and demands. The Alternating Direction Method of Multipliers (ADMM) algorithm is adopted for distributed solution. Case studies demonstrate that the connection topology between micro-energy grids significantly impacts the total operating cost, and the effectiveness of the ADMM algorithm is validated through a comparison with centralized optimization approaches. [ABSTRACT FROM AUTHOR]

Adapting to horizontal market structures faces several drivers and challenges in the context of sustainable energy transition. The inherently decentralized nature qualifies blockchain technology as the major technical driver in the transition to peer-to-peer (P2P) energy market models. One major technical challenge encountered in the transition process is the active power loss associated with transactions, which can cause network congestion and economic loss. A review of existing research on the P2P transaction active power loss problem, examining the potential role of blockchain and the consequent additional costs incurred by blockchain transactions, is presented in this article. Consolidating major points and guiding observations for future research are provided to address the challenges while adapting to the potential driving blockchain technology. A conceptual peer-to-peer trading framework that considers blockchain transaction cost and active power loss compensation is also presented. [ABSTRACT FROM AUTHOR]

The enhancement of economic sustainability and the reduction of greenhouse gas (GHG) emissions are becoming more relevant in power system planning. Thus, renewable energy sources (RESs) have been widely used as clean energy for their lower generation costs and environmentally friendly characteristics. However, the strong random uncertainties from both the demand and generation sides make planning an economic, reliable, and ecological power system more complicated. Thus, this paper considers a variety of resources and technologies and presents a coordinated planning model including energy storage systems (ESSs) and grid network expansion, considering the trustworthiness of demand-side response (DR). First, the size of a single ESS was considered as its size has a close effect on maintenance costs and ultimately affects the total operating cost of the system. Second, it evaluates the influence of the trustworthiness of DR. Third, multiple resources and technologies were included in this high-penetration renewable energy integrated power system, such as ESSs, networks, DR technology, and GHG reduction technology. Finally, this model optimizes the decision variables such as the single size and location of ESSs and the operation parameters such as thermal generation costs, loss load costs, renewable energy curtailment costs, and GHG emission costs. Since the problem scale is very large not only due to the presence of various devices but also both binary and continuous variables considered simultaneously, we reformulate this model by decomposition. Then, we transform it into a master problem (MP) and a dual sub-problem (SP). Finally, the proposed method is applied to a modified IEEE 24-bus test system. The results show computational effectiveness and provide a helpful method in planning low-carbon electricity power systems. [ABSTRACT FROM AUTHOR]

With the continuous advancement of the new generation of information technology revolution, digital economy is gradually becoming an important driving force for energy transition while restructuring the new form of the economy. This paper selects panel data of 30 provinces in China from 2011 to 2021, empirically verifies the special impacts of digital economy on green- oriented transition of energy by using the spatial Durbin model, and further constructs a multi-intermediary model to verify its transition pathways. The main findings are as follows: First, the overall level of green-oriented transition of energy in China's eastern coastal areas is relatively high, and the western regions have been more capable of catching up in recent years. Second, digital economy has played a significant role in promoting green-oriented transition of energy, and there is a positive spatial spillover effect. Third, digital economy could indirectly promote the green-oriented transition of energy by promoting the upgrading of industrial structure, improving the level of technological innovation and strengthening environmental regulations. This study provides empirical insights and reference for policymakers in accelerating the comprehensive green-oriented transition of energy. [ABSTRACT FROM AUTHOR]

Introducing solar and wind power into distribution networks (DNs) is an important initiative to promote the cleanliness and low-carbonization operation of DNs. However, the source and load outputs are uncertain in DNs, which will lead to problems of inaccurate regulation and insufficient renewable energy utilization. Therefore, this study provides an efficient multi-timescale regulation strategy for DNs based on active and passive resources combined. First, the day-ahead regulation model is constructed to minimize the total operating cost in a day for DNs. It aims to determine the on-load tap changer (OLTC) and capacitor bank (CB) switching schemes and consider them as the constraints for intraday regulation by power flow unification. Then, an intraday source and load uncertainty model is considered, which aims to cope with the problems of inaccuracies in the day-ahead source and load prediction. Based on this, the objective function of the intraday regulation model is set. It aims to minimize the deviation from the total day-ahead cost and then ensure the optimal system economy and determine the intraday new energy and energy storage system (ESS) short-time action scheme. Finally, the example results show that the proposed scheme can achieve the maximum utilization of renewable energy and improve the low-carbon economic operation of the whole system. [ABSTRACT FROM AUTHOR]

In this paper, a two-layer optimization approach is proposed to facilitate the multi-energy complementarity and coupling and optimize the system configuration in an electric-hydrogen-integrated energy system (EH-IES). Firstly, an EH-IES with virtual energy storage is proposed to reduce the cost of physical energy storage equipment. Secondly, a two-layer optimal allocation method is proposed under a multi-timescale strategy to examine the comprehensive evaluation index of environmental protection and economy. The upper layer utilizes the NSGA-II multi-objective optimization method for system capacity allocation, while the lower layer performs economic dispatch at the lowest cost. Ultimately, the output includes the results of the equipment capacity allocation of the EH-IES that satisfies the reliability constraint interval and the daily scheduling results of the equipment. The results demonstrate that the electric-hydrogen-integrated energy system with the coupling of multiple energy equipment not only enhances the utilization of RENEWABLE energy sources but also reduces the usage of fossil energy and improves the system's reliability. [ABSTRACT FROM AUTHOR]

The insufficient exciton (e−‐h+ pair) separation/transfer and sluggish two‐electron water oxidation are two main factors limiting the H2O2 photosynthetic efficiency of covalent organic frameworks (COFs) photocatalysts. Herein, we present an alternative strategy to simultaneously facilitate exciton separation/transfer and reduce the energy barrier of two‐electron water oxidation in COFs via a dicyano functionalization. The in situ characterization and theoretical calculations reveal that the dicyano functionalization improves the amount of charge transfer channels between donor and acceptor units from two in COF‐0CN without cyano functionalization to three in COF‐1CN with mono‐cyano functionalization and four in COF‐2CN with dicyano functionalization, leading to the highest separation/transfer efficiency in COF‐2CN. More importantly, the dicyano group activates the neighbouring C atom to produce the key *OH intermediate for effectively reducing the energy barrier of rate‐determining two‐electron water oxidation in H2O2 photosynthesis. The simultaneously enhanced exciton separation/transfer and two‐electron water oxidation in COF‐2CN result in high H2O2 yield (1601 μmol g−1 h−1) from water and oxygen without using sacrificial reagent under visible‐light irradiation. COF‐2CN can effectively yield H2O2 in water with wide pH range, in different real water samples, in scaled‐up reactor under natural sunlight irradiation, and in continuous‐flow reactor for consecutively producing H2O2 solution for water decontamination. [ABSTRACT FROM AUTHOR]

The evolution of power system is a dynamic and complex process. Whether the evolution of power system can adapt to the macro environment and develop with all subsystems within the system depends on the matching and integration development among different evolutionary subjects. Based on the dissipation theory and Brusselator model, this paper constructs an evolutionary synergy model of the power system, and quantitatively analyzes the evolutionary synergy relationship between the evolving subjects of the power system and the overall evolutionary process of the power system. Then, from the socio- technical system transformation theory, we analyze the evolutionary elements of macro-environmental level, meso-institutional level and micro-beneficial level in the process of system transformation in China and the interaction among them. Finally, by comparing the entropy changes of the evolutionary participant subjects and the overall power system at each stage, the endogenous mechanism of the power system, the external elements and their interactions on the system development are studied in order to reveal the evolutionary synergistic law of China's power system and make suggestions for the development of the new power system. [ABSTRACT FROM AUTHOR]

Harmonic and power quality issues brought by the high power electronics penetration level have become a rising threat to power grids. To achieve accurate measurement of the broadband harmonics caused by the power electronic devices, the broadband phasor measurement unit has been developed and installed. However, due to its high cost, it is less practical to install bPMU on each node, and therefore, how to obtain the global harmonic state in the power grid with minimum bPMUs is a crucial issue. This paper is focused on the harmonic state estimation method based on bPMU data. The mathematical model for harmonic state estimation is first derived based on circuit principles. Then, the weighted least squares method is then utilized to solve the established measurement equations for harmonic state estimation to obtain the harmonic state across the grid. Furthermore, the 0-1 integer programming approach is employed to optimize the installation locations of the bPMUs to reduce the overall cost while maintaining full observability. Subsequently, the harmonic sources are localized by analyzing the injected harmonic power on each node. Finally, the validity and effectiveness of the proposed method are proved by matching results between the proposed methods and the simulation model based on the IEEE 14- node system. [ABSTRACT FROM AUTHOR]

Background: Osteosarcoma (OS) is a common malignant bone cancer and usually occurs in adolescents and children. Circular RNAs (circRNAs) play essential roles in tumor development and progression. This study aimed to explore the function and molecular basis of circ_0016347 in OS progression. Materials and Methods: The levels of circ_0016347, miR-1225-3p, and ether à go-go 1 (KCNH1) were measured by quantitative real-time polymerase chain reaction or Western blot assay. Cell proliferation was assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and colony formation assay. Cell migration and invasion were evaluated by transwell assay. Glucose consumption and lactate production were detected by glucose detection and lactic acid detection kits. The levels of Ki-67, matrix metalloproteinase-9 (MMP-9), and hexokinase-2 (HK2) were examined by Western blot assay. The interaction among circ_0016347, miR-1225-3p, and KCNH1 was validated by dual-luciferase reporter assay. Xenograft assay was conducted to analyze tumor growth in vivo. Results: Circ_0016347 and KCNH1 were upregulated, while miR-1225-3p was downregulated in OS tissues or cells. Circ_0016347 and KCNH1 promoted proliferation, migration, invasion, and glycolysis of OS cells. Circ_0016347 regulated OS progression by modulating KCNH1. Circ_0016347 was a sponge of miR-1225-3p, and miR-1225-3p targeted KCNH1. Circ_0016347 regulated KCNH1 expression via sponging miR-1225-3p. Moreover, silencing of circ_0016347 inhibited tumor growth in vivo. Conclusion: Circ_0016347 contributed to OS progression through the miR-1225-3p/KCNH1 axis, which might provide a promising biomarker for OS therapy. [ABSTRACT FROM AUTHOR]