Abstract:It is a general trend for renewable energy represented by wind power to participate in the electricity spot market, but the uncertainty of wind power output makes its market competitiveness weak, while the uncertainty of electricity price further increases the revenue risk it bears. Combining hydropower with flexible regulation capabilities is an effective solution, and formulating bidding strategies that align with the risk willingness of decision-makers is a key issue that needs to be solved urgently. Therefore, from the perspective of price takers, a bidding model of hydropower combined with wind power participating in the electricity spot market is proposed. In the model, a typical scenario set after Cartesian product combination is used to describe multiple uncertainties such as wind power output and market price, the conditional value at risk (CVaR) is used to measure the market risk caused by uncertainties, and the risk factor is included in the decision-making process as the risk preference of the decision-makers. The nonlinear function in the model is solved by introducing 0/1 integer variables and transforming it into a mixed-integer linear programming (MILP) model. The effectiveness of the model is validated against the background of a cascade hydropower station and a wind farm in a certain province in Southwestern China, and the impact of risk preference on bidding decisions is further analyzed.

Abstract:With the advancement of electricity market reform, all provincial markets in East China region have been in the trial operation stage. In order to balance the smooth operation of the electricity spot market and the safe operation of regional power grid, it is urgent to study a more efficient region-province cooperative operation mechanism. First, the challenges and thoughts for the improvement of region-province scheduling cooperative mode under the background of electricity spot market are analyzed. Then, the feasible region models of the regional power grid scheduling and provincial and municipal scheduling are constructed, and the method for dimensionality reduction and linearization of the feasible region model is proposed. On this basis, a region-province cooperative and optimized operation mechanism based on the scheduling feasible region is proposed, which focuses on exploring the business process of region-province two-level cooperative operation and the calculation method of provincial and municipal feasible regions. Finally, the effectiveness of the scheduling feasible region model and the two-level market cooperative operation mechanism is verified through the analysis of regional power grid cases.

Abstract:The increase in the proportion of renewable energy has led to a significant increase in the requirement for flexible regulation resources in the power system. However, the traditional capacity market only aims to guarantee the system adequacy during the peak load period. There may still be a shortage of power supply due to insufficient flexible regulation capacity. Therefore, this paper proposes a robust optimal clearing model and a pricing method for the capacity market that considers the flexible regulation requirement. The settlement rules for different resource types are provided. And it is verified that the proposed capacity market pricing mechanism can satisfy the properties of social efficiency, balance of payments, individual rationality, and incentive compatibility. Finally, the IEEE 118-bus system is used for the case study. The results show that the proposed capacity market mechanism can simultaneously guarantee the adequacy of the system to cope with peak load and flexible regulation requirement, reasonably describe the capacity value of flexible regulation resources, and effectively distinguish between the effective capacity contribution of different types of resources and the responsibility of causing flexible regulation requirement, which helps to guide renewable energy units to suppress their output uncertainty fluctuations and incentivize flexible resources to provide capacity to meet system flexible regulation requirement.

Abstract:The launch of national green electricity trading provides a sufficient market-based approach for the realization of the environmental value of green electricity under the background of low-carbon transformation in the power system. With the large-scale permeation of various trading entities and the diversification of green electricity demand on the user side, the current green electricity trading mechanism needs further research to improve flexibility and credibility of certification. It is urgent to optimize the mechanism design to meet the requirements of refined transaction involving massive entities and the reasonable value distribution. Thus, a dual-account mechanism for green electricity trading based on the blockchain technology is proposed in this paper. First, the dual-account management mechanism consisting of the trading account and consumption account is set up,where the circulation of green property and the generation of consumption certificates are recorded separately. Combining with the circulation of green properties, the transaction mode of “coordination of certification and electricity” is designed, which aims to achieve effective connection between green electricity trading and green certificate trading. Finally, the rule contract writing, post-verification design of each transaction process, and block storage design of consumption certificate are carried out for green electricity trading from the perspective of blockchain technology. Trading entities are evaluated by using the historical performance rate to reduce the risk of market operation. The case experiment shows that the mechanism can effectively improve the flexibility and credibility of green electricity trading and alleviate the pressure of renewable energy subsidies to a certain extent.

Abstract:The medium- and long-term electricity market in China has achieved good results after years of construction. But with the construction of new power systems, the overall market structure has changed, and medium- and long-term trading faces new challenges in achieving market connection and integration, supporting the entry into the market and consumption of renewable energy. This paper first outlines the key points for the construction of the medium- and long-term market at the current stage. Then, a review and commentary of the current medium- and long-term market trading mechanisms are conducted from four aspects: differences in trading rules, connection with the spot market, coordination between the two markets, and operation of the green electricity market. Finally, suggestions are proposed for the construction direction of the future medium- and long-term market from the perspective of market unity and green development.

Abstract:Under the continuous increase in the proportion of renewable energy, the inter-provincial consumption demand has been steadily rising. Establishing an inter-provincial electricity market that meets the overall resource optimization operation is crucial to promoting market efficiency. A bi-level clearing model of the inter- and intra-provincial electricity spot markets is established based on the time-coupling relationship of multiple block orders and hourly orders. Firstly, a mixed-integer linear programming model is constructed, encompassing multiple orders including ordinary hourly orders, flexible hourly orders, conventional block orders, removable block orders, and extended linked block orders. Secondly, to address the challenge of clearing difficulty arising from the complexity of inter-temporal coupling in block orders and the large number of inter-provincial market entities, a screening mechanism for the entities participating in inter-provincial market is proposed, which is based on the intra-provincial clearing results. Furthermore, the inter-provincial market clearing based on the selected entities from each province is realized, and the final winning bid result is formed by integrating the inter- and intra-provincial clearing results. Finally, the rationality and effectiveness of the model are verified through a case of IEEE RTS-96 system interconnected in multiple regions. The results indicate that, compared with individual provincial clearing, the bi-level clearing of the inter- and intra-provincial markets can enhance the overall social welfare. The proposed method can not only improve the solving efficiency, but also approach the global optimal solution to the inter-provincial overall clearing, thereby maximizing the social welfare.

Abstract:The inter-provincial electricity spot market has been continuously operating for more than two years. Based on the implementation of inter-provincial medium- and long-term transactions, it has achieved market-oriented electricity surplus and shortage mutual assistance and large-scale optimal allocation of resources. The practice shows that the inter-provincial electricity spot market has played an important role in improving the supply capacity of the whole power grid and promoting the consumption of clean energy. Firstly, this paper describes the trial operation and effectiveness of the inter-provincial electricity spot market since 2022. Secondly, the mechanism of inter-provincial electricity spot trading is analyzed from the market framework, the clearing mechanism, and the declaring mechanism. Finally, based on the current situation of inter-provincial electricity spot market construction, the future development directions are prospected.

Abstract:Offshore wind power will become an important technological option for China to achieve carbon emission peak and carbon neutrality due to its more utilization hours for electric power generation. However, with the continuous increase in the offshore wind power installed capacity, its intermittency and fluctuation will have a significant impact on the security and stability of power systems, as well as the economic operation of electricity markets. To characterize the correlation between wind speeds at different station sites, the vine copula theory is used for offshore wind power modeling and a joint distribution model is constructed for multiple wind farms by using the C-vine copula function. On this basis, a method is proposed for constructing the typical congestion scenarios in the electricity market based on the consensus clustering. Numerical simulation calculations are conducted with the simplified power grid architecture data of Guangdong province, China to empirically analyze the changes in key indicators such as generation structure of the power system, carbon emissions, and market electricity prices before and after the large-scale grid-integration of offshore wind power.

Abstract:The development experience of the European unified electricity market can provide significant inspiration for the construction of the Chinese electricity market. The day-ahead electricity market is the basic link and essential component of the European unified electricity market. Firstly, the basic situation of the European day-ahead electricity market is sorted out, the concept of main market orders is introduced, and the characteristics and applications of market orders are further summarized and compared. Secondly, the basic model for European day-ahead electricity market clearing is built, the main process of the solution algorithm is given, and its basic principle is analyzed. At the same time, the case analysis and application expansion are carried out. Finally, combined with the research focus on the European day-ahead electricity market, the future development trends are analyzed, and the enlightenment and suggestions for the construction of the Chinese electricity market are summarized and proposed.

Abstract:In order to adapt to the new trend of capacity resource diversification and the new requirements of investment incentive in the new power system, aiming at the construction problem of sufficiency guarantee mechanism for generation capacity in China, the capacity subsidy electricity price mechanism and capacity evaluation method are constructed with consideration of diversified source, storage and load resources. First, based on the theory of marginal generation cost, the “lack of money” problem in the pure electric energy market and the principle of capacity pricing are revealed, the method of setting capacity subsidy electricity price is put forward, and the capacity adjustment coefficient is introduced to effectively stimulate investment. Then, combined with the different characteristics of source, storage and load resources, the peak load capacity support is provided for the system, the active power output and scheduling models of wind, solar and water renewable power sources and new load storage entities are established, and the two-state method is integrated to construct various component models. The reliability evaluation method of sufficient capacity of diversified resources is established by using the sequential Monte Carlo simulation. On this basis, a practical evaluation method for classification differences is proposed, which overcomes the defects of traditional evaluation methods of wind,solar,energy storage and load, scientifically reflects the actual contribution of various resources to capacity support, and takes into account the simplicity and transparency of calculation. Finally, the case verification shows that the mechanism can realize fair compensation, provide scientific power generation investment signal, and ensure cost recovery, sufficient generation capacity and stable electricity price. The practical evaluation method better balances the relationship between evaluation accuracy and policy implementation.

Abstract:The evaluation and certification of green electricity consumption are critical in the construction of the green electricity market. Currently, there is a lack of effective technical verification methods for evaluating and certifying green electricity consumption. Moreover, the evaluation process faces technical challenges regarding privacy protection of green electricity consumption data. An evaluation and certification model of green electricity consumption based on privacy computing is proposed. First, a novel homomorphic encryption method is devised to support the privacy protection of multiple parties involved in evaluation of green electricity consumption. In contrast to traditional homomorphic encryption algorithms, this method demonstrates higher efficiency in the encryption and decryption processes, and the procedure of encryption and decryption can be segmented while maintaining full homomorphism. Then, a collaborative privacy computing model of homomorphic encryption and trusted execution environment (TEE) is proposed to solve the problem that the traditional homomorphic encryption algorithm can not support the nonlinear operation in ciphertext, and the calculation and storage cost are high. Finally, based on the verifiability mechanism of the computing process of TEE and the tamper-proof characteristics of blockchain certificate data, a reliability assurance mechanism of green electricity consumption evaluation results is established. Theoretical and experimental results demonstrate that the proposed scheme can efficiently compute the evaluation data involving privacy protection for green electricity consumption, which takes approximately 0.114 seconds to complete the green electricity consumption evaluation of privacy protection for 10 000 consumers.

Abstract:Pumped storage power stations, as effective flexibility resources for power systems, will become crucial in ensuring the safe and stable operation of new power systems. The formulation of reasonable schemes for recovering the fixed costs of construction of pumped storage power stations is a key issue in supporting system operation and stimulating investment. In the context of marketization operations for pumped storage power stations, this paper constructs a capacity charge pricing model that sequentially integrates the pumped storage power stations into the spot and ancillary service markets, achieving regular recalibration of the unallocated costs of pumped storage power stations with the objective of revenue and expenditure balance during the operation period. Meanwhile, considering the potential entities for allocating the capacity charges of pumped storage power stations, a utility-proportional Vickrey-Clarke-Groves (VCG) mechanism is proposed to allocate costs of the capacity charges of pumped storage power stations, quantify the substitutive benefits of allocation entities on both the source and load sides, and proportionally allocate the capacity charges. Effectiveness of the proposed method is validated through simulation analysis of actual system cases.

Abstract:In the context of the low-carbon transformation of the energy system, the operation of electricity markets in various countries faces multiple policy boundaries. To solve the problem of how governments should intervene in markets to achieve multiple objectives, further research on hybrid electricity markets is conducted based on the two-stage market competition theory, combined with the driving relationship between government and market in the electricity market system. First, the equilibrium principles and challenges of traditional electricity markets are deeply analyzed, and the reasons for government intervention in electricity markets are classified and discussed, including externalities, imperfection in the market system, imperfection in market mechanisms, and imperfection in market competition. Then, the significance and challenges of the basic structure of hybrid electricity markets based on the two-stage market competition theory are discussed. On this basis, a two-dimensional four-module hybrid electricity market extension structure is proposed, which includes short-term and long-term, market and government. And the key steps and contents of its design are analyzed. Finally, the design of government intervention methods in hybrid electricity markets is discussed based on the problems existing in China’s electricity market construction.

Abstract:With the continuous promotion of the construction of the China southern regional electricity market, there have been cases of cross-section overlimit due to the dispatch of unit frequency regulation capacity during the trial operation of power regulation in the regional electricity spot market. In order to improve the efficiency of security verification and achieve the effective integration of the frequency regulation security verification process with the electricity spot market, a real-time security verification optimization strategy for the whole process of the frequency regulation auxiliary service market is proposed. A refined cross-section classification strategy suitable for regional power grids is optimized and designed to quickly screen the closed and connected sections of frequency regulation units to improve the security verification efficiency. For different types of cross-sections, typical scenarios for the dispatch of frequency regulation capacity considering third-party independent energy storage and adjustable loads are designed. Random automatic generation control (AGC) instructions are then transformed into deterministic scenarios for the dispatch of frequency regulation capacity. On this basis, two connection paths between the frequency regulation security verification and the electricity spot market are proposed to meet the different needs of different stages in regional electricity spot market construction. Finally, the accuracy and effectiveness of the proposed method are verified based on the actual operation of the frequency regulation market in southern China.

Abstract:With the integration of large-scale renewable energy, the secure power-supply ensurance situation of power grids has become increasingly severe. Under this background, a joint clearing mechanism for electric power energy and balance regulation service is established with consideration of the external security costs of renewable energy. The electric power energy costs and the balance regulation service costs are coupled and superposed,and through the joint clearing, the balance regulation service is organized in a market-oriented manner to reflect the energy value and the security value of electric power energy at a reasonable price, so as to give a clear price signal to facilitate the sharing of balance responsibilities. Finally, through the case analysis, it is verified that the proposed operation mechanism has the significant advantages in terms of economy and robustness.