Privacy-preserving and accountable billing in peer-to-peer energy trading markets with homomorphic encryption and blockchain

This paper proposes a novel Privacy-preserving and Accountable Billing (PA-Bill) protocol for peer-to-peer energy trading markets. It addresses the challenges of discrepancies between committed and delivered energy volumes, ensuring accurate billing, privacy, and accountability. PA-Bill employs a universal cost-splitting mechanism to enhance fairness and prevent indirect privacy leakage. The protocol leverages homomorphic encryption to protect user data and uses blockchain technology to maintain accountability through an immutable and transparent distributed ledger. Additionally, it includes a dispute resolution mechanism to rectify erroneous bill calculations and identify responsible parties, thus ensuring non-repudiation. Our experimental and theoretical evaluations demonstrates that PA-Bill effectively supports large communities of up to 2000 households, offering a computationally efficient, privacy-preserving, and accountable billing solution in a semi-decentralised manner.