关键词: 市场化交易模式, 产消者, 微分博弈, 非对称信息

Abstract: Motivated by the energy transition and low-carbon energy system construction, renewable energy such as photovoltaic has developed rapidly. Traditional and centralized energy systems are gradually giving way to clean and decentralized ones. As a result of continuous policy incentives and advancements in power generation technology, grid-connected distributed photovoltaic has gradually become the main feature of the power system. Through this process, passive energy consumers have become active prosumers who produce and consume energy. Prosumers have gradually become innovative solutions for meeting emission reduction targets and alleviating supply and demand contradictions. Grid stability has been challenged by the uncertainties of generation as grid-connection scales grow rapidly. Increasingly, prosumers are participating in distribution network competition. Government officials are gradually promoting market-based trading of distributed energy resources in order to encourage nearby consumption. And a variety of transaction modes have been derived.
For the past several years, the reform process has been slow and is still in the pilot stage. The grid-connection of prosumers has been transformed from being subsidy-driven to being market-driven in the post-subsidy era. And transaction modes are crucial to grid-connected benefits. Taking into account the interaction between subsidy regression and reduced power generation costs, different market transaction modes do not seem to have a significant incentive effect. Due to this, the government will have difficulty formulating effective promotion strategies in the complex market environment. A second reason for the slow progress of reform is the imperfect trading mechanism. Especially in the regulated electricity market, the asymmetric information between prosumers and government can easily lead to market failure. Therefore, this paper constructs a set of distributed market-oriented trading theoretical frameworks. The results can be used to develop market-oriented trading strategies and alleviate consumption problems.
This paper discusses three different distributed market transaction modes, namely net-metered, virtual power plant, and peer-to-peer. Under an asymmetric information market environment, a two-level differential game model including prosumers and government is constructed based on principal-agent theory. Moreover, our model incorporates generation uncertainty, subsidy decline, and levelized costs of PV into the strategy selection process. Using actual data from Shanghai and Shandong pilots, the incentive effects of different trading modes are numerically simulated in depth. A comprehensive comparison is made using four dimensions of social welfare, grid-connected benefits, information rents and grid-connected electricity.
According to the results, market-oriented energy transactions have significantly promoted distributed energy consumption. In order to maximize consumption and social welfare, P2P, supplemented by VPP, is more conducive to achieving the goal. Prosumers in the P2P mode face deviation assessment costs due to uncertainty, but the competitive environment lowers transaction costs, and prosumers are more willing to transact. As a result of asymmetric information, prosumers obtain non-negative information rent. The development of a regulatory mechanism for identifying the true costs of prosumers is urgently needed. A decline in subsidies reduces the enthusiasm of prosumers even resulting in the emergence of negative utility. The existence of local subsidies, however, can provide a buffer for grid parity. Nevertheless, cost reductions can offset the negative impact of subsidy declines, and an industry technological advancement is a long-term task. The follow-up study can provide a comprehensive analysis of multiple scenarios under VPP and risk preferences of prosumers under P2P.

Key words: market-oriented transaction mode, prosumer, differential game model, asymmetric information