An air-conditioning system comprising a refrigerant circuit to which a compressor, a utilization-side heat exchanger performing air conditioning of an indoor space, and a thermal storage heat exchanger are connected, and which is configured to perform a refrigeration cycle, the air-conditioning system being configured to execute a first operation in accordance with a reduction command to reduce commercial power consumption in a whole of the air-conditioning system, the first operation allowing the utilization-side heat exchanger to perform air conditioning using the thermal storage heat exchanger as a heat source, and the air-conditioning system including a power reduction section (5, 11, 100) configured to perform a first control in synchronization with timing of a start of the first operation, the first control making the commercial power consumption in the whole of the air-conditioning system equal to or lower than a first value, wherein the power reduction section includes the compressor, and a control device configured to control, in the first control, the compressor such that the commercial power consumption in the whole of the air-conditioning system is made equal to or lower than the first value, characterized in that at the start of the first operation, the control device is configured to perform the first control if the commercial power consumption exceeds a second value, and is configured to perform a second control if the commercial power consumption is equal to or lower than the second value, the second control controlling the compressor such that the air-conditioning capacity of the utilization-side heat exchanger is brought close to the required capacity regardless of the commercial power consumption. a refrigerant circuit to which a compressor, a utilization-side heat exchanger performing air conditioning of an indoor space, and a thermal storage heat exchanger are connected, and which is configured to perform a refrigeration cycle, the air-conditioning system being configured to execute a first operation in accordance with a reduction command to reduce commercial power consumption in a whole of the air-conditioning system, the first operation allowing the utilization-side heat exchanger to perform air conditioning using the thermal storage heat exchanger as a heat source, and the air-conditioning system including a power reduction section (5, 11, 100) configured to perform a first control in synchronization with timing of a start of the first operation, the first control making the commercial power consumption in the whole of the air-conditioning system equal to or lower than a first value, wherein the power reduction section includes the compressor, and a control device configured to control, in the first control, the compressor such that the commercial power consumption in the whole of the air-conditioning system is made equal to or lower than the first value, the compressor, and a control device configured to control, in the first control, the compressor such that the commercial power consumption in the whole of the air-conditioning system is made equal to or lower than the first value, characterized in that at the start of the first operation, the control device is configured to perform the first control if the commercial power consumption exceeds a second value, and is configured to perform a second control if the commercial power consumption is equal to or lower than the second value, the second control controlling the compressor such that the air-conditioning capacity of the utilization-side heat exchanger is brought close to the required capacity regardless of the commercial power consumption.