A privacy-preserving consensus mechanism for an electric vehicle charging scheme

Abstract

The increasing adoption of Electric Vehicles (EVs) brings opportunities for electric power transactions for users to be able to trade their excess electricity. Blockchain technology is envisaged as an electricity exchange platform to minimise the time gap and cost in the trading process. We propose a public electric power exchange service network with a gateway-based privacy-preserving scheme to implement authentication and data encryption for EV charging and discharging from grid peers. A novel consensus mechanism Proof-of-Benefit (PoB) is designed to support automated smart contracts for electric power trading, in which a benefit number generation algorithm is proposed to select the leader for the transaction validation. Meanwhile, the authentication strategy ensures only the participated nodes with valid identities can access the consensus process, and the data encryption is applied to avoid EV behaviour analysis based upon plain transaction flows that would otherwise be exposed in the network. Through theoretical and experimental analysis, a public electric power exchange service platform with a PoB consensus mechanism achieves a higher scalability and lower grid load variance while maintaining a high accuracy rate of correct electric power transactions against Sybil attacks and a faster (lower time consumption) authentication process when compared with other blockchain-enabled authentication methods (e.g. FairAccess, Bubbles of trust, and so on) used as the baseline.