A method for controlling a heating, ventilation, and air-conditioning (HVAC) system of an autonomous vehicle includes determining a vehicle operating status and operating the HVAC system according to the determined vehicle operating status. A control module comprising a sensor array and at least one controller operatively coupled to the sensor array and to the HVAC system controls operation of the HVAC system according to the determined vehicle operating status. The vehicle operating status is selected from one of vehicle occupied-in use, vehicle unoccupied-use requested, and vehicle unoccupied-standby. The HVAC system is operated at an operating setting providing a reduced energy consumption in a vehicle whose operating status is vehicle unoccupied-standby. The reduced energy consumption operating setting is determined according to a constant offset value or according to a variable offset value determined by inputs provided by the sensor array.