OPERATION PLANNING SYSTEM

In formulating of a power generation operation schedule to a power grid network including multiple power plants and transformer stations, and, multiple batteries installed in association therewith, an operation planning system stores in advance power generation basic unit information of the power plant, and derivation information of the stored energy in the battery. Power generation basic unit information of the battery where power generation basic unit of the stored energy is added is set based on the power generation basic unit information of the power plant and the derivation information of the stored energy. While selecting a power generation facility from the power plants and the batteries in an order of a smaller value indicated by the power generation basic unit information, the power generation quantity of the selected power generation facility is added to a total power generation quantity until the total power generation quantity matches a demand quantity.