An air-conditioning system (1) comprising a demand controller (10) for controlling the total consumed electric energy of air-conditioning loads. To enhance the amenity during demand control the system (1) is provided with an air conditioner (20) having a coolant circuit and adapted to handle the sensible heat load in the room and a humidifier (30) having adsorbing members (32,33) and adapted to handle the latent heat in the room, and the humidity in the room is regulated by the humidifier (30) according to the demand control levels while controlling the evaporation temperature of the coolant circuit constituting the air conditioner (20).
