Vehicle air-conditioning system and vehicle air-conditioning method

A vehicle air-conditioning system has an intake door that switches between an inside air recirculation mode to take in air from an inside air introduction port and an outside air introduction mode to take in air from an outside air introduction port, a blower that blows the air introduced through any of the inside air introduction port and the outside air introduction port toward inside of a vehicle cabin, a heater that heats the air blown by the blower, and a controller that activates the heater when there is a request for heating the inside of the vehicle cabin, controls air conditioning such that an environment inside the vehicle cabin becomes a desired environment by set estimated time of departure.