Navigation device and method for route calculation

摘要

A navigation device includes: a position detecting unit; a remaining energy level detecting unit; a storage unit that stores map information including position information of a charging point of a drive energy; an energy consumption amount calculation unit that calculates a consumption amount of the drive energy when a vehicle travels along any link included based upon the map information; a route calculation unit that calculates a route from a current position to a destination point; and a route guidance unit. The route calculation unit calculates a recommended route with a minimum attainment cost among routes in which the remaining level does not fall below a predetermined threshold level based upon the map information, the remaining level on departure of the vehicle detected by the remaining energy level detecting unit, and the consumption amount calculated by the energy consumption amount calculation unit.