A blockchain-based framework for privacy-preserving and verifiable billing in smart grid

Smart grid allows the electricity service provider (ESP) to provide reliable, accurate and efficient services to users. To protect the privacy of the collected smart meter data that may contain the private information of users, these data should be transmitted and stored at the ESP side in ciphertext format. However, due to the limited storage capability, the readings are not maintained at the user side, which brings the challenge for users to verify the correctness of electricity consumption bills. To address these issues, this paper proposes a blockchain-based privacy-preserving billing (BPB) framework based on the BGN encryption scheme, which allows ESP to produce monthly bills for users and supports the user to request ordinary bill for any period. Compared with existing solutions, our BPB construction supports ordinary bill request. Security analysis demonstrates that the proposed BPB construction can guarantee the privacy of smart meter readings, and the integrity and correctness of monthly bill and ordinary bill. Performance analysis indicates the efficiency of a BPB instantiation in applications.