In one embodiment, there is provided a charge-discharge instructing apparatus. The apparatus includes: an acquiring module configured to acquire specific information and location information for each of a plurality of battery energy storage systems, wherein the specific information represents an electrical characteristic of a battery of each of the battery energy storage systems, and the location information represents an installation position of each of the battery energy storage systems; a group determining module configured to select some of the battery energy storage systems from among the plurality of battery energy storage systems to make a group composed of the selected battery energy storage systems, based on the specific information and the location information; and a managing module configured to send a charge-discharge control instruction to the battery energy storage systems belonging to the group.