A double auction mechanism for virtual power plants based on blockchain sharding consensus and privacy preservation

Abstract

Virtual power plants (VPPs) represent an effective way to aggregate various distributed energy resources (DERs) to participate in the double auction market. Currently, the surge in DERs and associated data poses great challenges to the trust and data privacy of VPPs. Blockchain technology has emerged as a solution to enhance both trust and security in a VPP network. However, the VPP blockchains suffer from inference attacks and limited throughput. To this end, this study proposes an innovative privacy-preserving VPP double auction mechanism that can effectively address the problems of scalability and privacy breaches in the existing methods. First, a proof of comprehensive energy ratio based on auction blockchain, which considers the renewable energy source ratio of VPPs, is established. Second, a sharding consensus strategy is designed to select mining nodes and validate transactions, boosting the efficiency and scalability of the blockchain during the auction. Third, the Rényi differential privacy and Dirichlet differential privacy are used separately to preserve sensitive data in the auction and consensus node election processes. The proposed method is verified by theoretical analysis and case studies, and the results demonstrate that the proposed model can improve the probability of mining rights and the income of VPPs with high renewable energy sources. Moreover, the privacy of VPPs can be preserved flexibly at a lower privacy cost by adjusting the privacy parameters. Finally, the computational efficiency of the auction blockchain is enhanced, and power consumption is saved by 54.64% on average.