Fuel-saving driving diagnostic device, fuel-saving driving diagnostic system, control device of prime mover, fuel-saving driving rating device, and fuel-saving driving diagnostic method

A fuel-saving driving diagnostic device comprising:

• a condition managing unit that manages an accelerator-off traveling condition which is a condition defining a control status of a vehicle for determining whether the vehicle is performing an accelerator-off traveling or not;
• a determining unit that determines whether the control status of the vehicle satisfies the accelerator-off traveling condition or not;
• an interval determining unit that determines whether an interval including a current traveling position of the vehicle is to cause the determining unit to make determination or not based on a condition of the current traveling position of the vehicle acquired by a road/traffic condition acquiring device that acquires a road condition and/or a traffic condition;
• a total-traveling-distance calculating unit that calculates a total traveling distance of the vehicle within the interval determined to cause the determining unit to make determination by the interval determining unit;
• an accelerator-off traveling distance calculating unit that calculates an accelerator-off traveling distance for which the determining unit determines that the control status of the vehicle satisfies the accelerator-off traveling condition;
• and
• a fuel-saving driving rating unit that rates a fuel-saving driving based on the total traveling distance calculated by the total-traveling-distance calculating unit and the accelerator-off traveling distance calculated by the accelerator-off traveling distance calculating unit.