Local Energy Trading Platform Based on Privacy-Preserving Blockchain with Linkable Ring Signature

The growing renewable energy source technologies and distributed communication infrastructure call for local energy trading (LET) platform in smart grid to assist prosumers and consumers to trade energy locally and efficiently. Blockchain is essentially a decentralized data storage and processing technology that can be used for transactions of any kind, which makes local energy transactions transparent, traceable and decentralized controlled. However, blockchain essentially presents a conflict between traceability and identity anonymity of transactions, which further brings a challenge for the conjunction of blockchain and the adaptation to various distributed fields, such as smart grid system. This paper proposes a blockchain-based regulated local energy trading platform. Identity anonymity is achieved by replacing traditional signature with ring signature. The traditional signature verification exposes signer's identity while ring signature verification in the latter includes all the identities of the ring, which hides real transaction identity. Further, when suspicious transaction happens, regulator is able to track down the malicious user by asking all the ring members to sign the suspicious transaction. Also, the proposed platform can resist quantum computing attack. We present the comprehensive concept, system design and simulation of the local energy trading platform based on a public blockchain, FISCO BCOS.