Secure Scalable Blockchain for Sealed-Bid Auction in Energy Trading

In this paper, we design and develop a scalable blockchain-based auction system for energy trading that outsources the execution of computation-intensive transactions to an off-chain network. The system is designed to promote peer-to-peer energy trading between electrical vehicles and energy suppliers. The idea is to reduce the burden on the blockchain by entrusting an off-chain network with the auction process. The off-chain network is composed of a small subset of nodes (validators) chosen randomly on-chain. The selected validators act as auctioneers to receive bids from energy suppliers, decide about the auction winner, and then announce it to the blockchain. In order to ensure the integrity of the decision made off-chain about the winner, the proposed winner is validated on-chain only if no dispute is raised by any of the bidders who participated in the auction. To secure the dispute process, the validators need to issue an acknowledgment receipt to each bidder using a Proof-of-Reception protocol, which consists of exchanging a digital receipt signed by at least one validator.