Change of a set room temperature of an air-conditioning apparatus leads to change of electric power consumed by the air-conditioning apparatus, and in a case of cooling, the consumed electric power increases as the set room temperature decreases. Consequently, a user has been unable to freely change the set room temperature. Thus, when the set room temperature is changed by the user, an evaporating temperature (refrigerant temperature) at which the electric power consumed by the air-conditioning apparatus does not change before and after the change is estimated and the air-conditioning apparatus is commanded for the evaporating temperature, which allows the user to pursue indoor comfort without worrying about the electric power consumed by the air-conditioning apparatus.