A balancing group is an intermediate layer between the market and demand sides playing a key role in maintaining the demand and supply balance within the group after the massive penetration of photovoltaic (PV) systems. In this paper, the balancing group formulates an optimal plan to guarantee a highly efficient operation of conventional generators and the group’s maximum output from PV generators simultaneously. The aggregator is provided a planned power flow (PPF) via a communication network by the balancing group in advance. Under these prerequisites, we propose a two-stage scheme for the demand side that consists of a day-ahead allocation algorithm of PPF and a real-time battery energy storage system (BESS) operation algorithm. The first stage of the scheme is almost the same as the case of the centralized effective BESS control, taking into account the maximum use of distributed BESSs. Owing to consumers’ demand diversity, the second stage of the scheme refers to a distribution generated using past data to reduce wasteful operation. The proposed approach is verified via a numerical simulation using a measured dataset from Ota City, Japan.