Server, and method of adjusting electric power supply and demand during charge or discharge of vehicle travels toward a destination route

A server used to adjust demand or supply of electric power, the server comprising:

• a storage storing data on a plurality of chargers each configured to charge or discharge electric power to or from a vehicle equipped with an electrical storage device;
• and
• a processor configured to send a user of the vehicle a message that makes a proposal to charge or discharge the vehicle by using at least one of the plurality of chargers when the vehicle travels toward a destination, wherein:
• the processor is configured to
• acquire, for each of the plurality of chargers, power supply and demand information relating to demand or supply of electric power in a power grid of a region in which the charger is installed,
• determine a priority of each of the plurality of chargers based on predetermined information including the power supply and demand information relating to demand or supply of electric power in the power grid of the region in which the charger is installed,
• extract, from among the plurality of chargers, a priority charger whose priority rank is higher than or equal to a predetermined rank, and
• send the message that makes a proposal to charge or discharge the vehicle by using the extracted priority charger.