A Comprehensive Review on Privacy-Preserving Metering in Smart Grid for Billing; Operation; and Rewarding Schemes, with Two Novel Solutions

In smart grid, the Utility Provider (UP) collects users power measurements' for two main reasons: billing and operation. Billing needs coarse-grained measurements where there are no, or minimal, privacy concerns. On the other hand, operation needs fine-grained measurements which can highly affect users' privacy. Hence, users might be reluctant to participate in operational metering to protect their privacy. To overcome this issue, UP might offer rewards to allure users to report their measurements which endangers their privacy. In this paper, we survey the literature on privacy-preserving metering in smart grid. We propose a new taxonomy to categorize the literature based on whether measurements need to be attributable to users or not. This categorization is highly effective because attribution is one of the main causes of privacy issues. Our survey shows that rewarding schemes and incentive-based demand response are new research topics with limited studies on it. Hence, we propose two privacy-preserving rewarding schemes for operational metering. First, a light-weight solution that utilizes an already established link of trust i.e. Banks. It is based on the assumption that banks will not leak a client account details. This solution is based on hash chains and blind signatures to assure users anonymity with minimal overhead for the UP and the smart meter. The bank in this approach is state-less in which is not required the bank to keep communications states of users and the UP. Second, we proposed another approach that does not rely on or banks or trusted third parties. It is based on Paillier homomorphic encryption and Pedersen commitments. It assumes that the smart meters are organized in a tree structure; which is widely used implementation in the literature. Security analysis for the proposed approaches is presented including unlinkability proof for measurements to users.