FSDA: Flexible Subset Data Aggregation for Smart Grid

Data aggregation is a practical method to protect individual privacy while using data utility, which aggregates the real-time electricity consumption data in an area into a single value in smart grids. Based on traditional data aggregation, multisubset data aggregation can obtain data distribution characteristics rather than just the sum of data. However, almost all existing multisubset aggregation schemes do not pay attention to adjusting the size of subsets according to the data distribution, which limits the data utility. In this article, a flexible subset data aggregation (FSDA) scheme based on Paillier homomorphic encryption for smart grids is proposed. The proposed FSDA scheme can dynamically adjust the size of each subset and aggregate the electricity consumption data into the corresponding subsets while protecting individual privacy. It is proved that FSDA scheme can obtain the distribution of consumption data and resist various internal attacks aiming to expose the individual or aggregated data. Experimental results show that FSDA scheme has lower overhead compared with related schemes, which is practical for resource-constrained smart meter devices.