An energy system comprising: an electric power controlling section which is configured to control transmission and reception of electric power between a power grid and an electric power storage device, the electric power storage device being mounted to a movable object or being transportable; an energy source producing section which is configured to utilize electric power supplied from the power grid to produce an energy source; an energy information obtaining section which is configured to obtain information indicating a first electric amount which is an electric power amount supplied by the electric power storage device to the power grid during a first period; a corresponding amount determining section which is configured to determine a first corresponding amount which is an amount of the energy source which the energy source producing section produces by utilizing an amount of electric power corresponding to the first electric amount; and a first suppliable amount determining section which is configured to determine, based on the first corresponding amount determined by the corresponding amount determining section, a first suppliable amount indicating a maximum value of an electric power amount which can be supplied from the power grid to the electric power storage device under a first economical condition, characterized in that the energy information obtaining section is configured to further obtain: information indicating a supplying location which is a location where the electric power storage device supplies electric power to the power grid during the first period; and information indicating a receiving location which is a location where the electric power storage device receives electric power from the power grid during a second period which is temporally after the first period, and the first suppliable amount determining section is configured to determine the first suppliable amount so that the first suppliable amount is higher in a case where the supplying location and the receiving location meet a first geographic condition than in a case where the supplying location and the receiving location does not meet the first geographic condition. an electric power controlling section which is configured to control transmission and reception of electric power between a power grid and an electric power storage device, the electric power storage device being mounted to a movable object or being transportable; an energy source producing section which is configured to utilize electric power supplied from the power grid to produce an energy source; an energy information obtaining section which is configured to obtain information indicating a first electric amount which is an electric power amount supplied by the electric power storage device to the power grid during a first period; a corresponding amount determining section which is configured to determine a first corresponding amount which is an amount of the energy source which the energy source producing section produces by utilizing an amount of electric power corresponding to the first electric amount; and a first suppliable amount determining section which is configured to determine, based on the first corresponding amount determined by the corresponding amount determining section, a first suppliable amount indicating a maximum value of an electric power amount which can be supplied from the power grid to the electric power storage device under a first economical condition, characterized in that the energy information obtaining section is configured to further obtain: information indicating a supplying location which is a location where the electric power storage device supplies electric power to the power grid during the first period; and information indicating a receiving location which is a location where the electric power storage device receives electric power from the power grid during a second period which is temporally after the first period, and the first suppliable amount determining section is configured to determine the first suppliable amount so that the first suppliable amount is higher in a case where the supplying location and the receiving location meet a first geographic condition than in a case where the supplying location and the receiving location does not meet the first geographic condition. information indicating a supplying location which is a location where the electric power storage device supplies electric power to the power grid during the first period; and information indicating a receiving location which is a location where the electric power storage device receives electric power from the power grid during a second period which is temporally after the first period, and the first suppliable amount determining section is configured to determine the first suppliable amount so that the first suppliable amount is higher in a case where the supplying location and the receiving location meet a first geographic condition than in a case where the supplying location and the receiving location does not meet the first geographic condition.