A heat exchange unit for a refrigeration apparatus using CO 2 as refrigerant and including a thermal storage unit and a utilization-side heat exchanger , comprising: at least one compressor , a heat-source-side heat exchanger an expansion device , a heat exchange unit gas port configured to communicate to the utilization-side heat exchanger disposed outside the heat exchange unit , a first heat exchange unit fluid port configured to communicate to the utilization-side heat exchanger , a second heat exchange unit fluid port communicating to the heat-source-side heat exchanger , a third heat exchange unit fluid port communicating to the expansion device , and a heat exchange unit gas communication pipe communicating between the heat exchange unit gas port and the at least one compressor , wherein an outlet of the at least one compressor is connected to an inlet of the heat-source-side heat exchanger by a refrigerant pipe, an outlet of the heat-source-side heat exchanger is connected to the second heat exchange unit fluid port by a first heat exchange unit fluid communication pipe , the third heat exchange unit fluid port is connected to an inlet of the expansion device by a second heat exchange unit fluid communication pipe and an outlet of the expansion device is connected to the first heat exchange unit fluid port by the Z second heat exchange unit fluid communication pipe , and the second heat exchange unit fluid port and the third heat exchange unit fluid port configured to communicate to the thermal storage unit including a thermal storage including or accumulating a thermal storage material , characterised in that the heat exchange unit further comprises a receiver , which is located on the second heat exchange unit fluid communication pipe , particularly between the first heat exchange unit fluid port and the expansion device , wherein the receiver is configured to separate liquid refrigerant and gas refrigerant. at least one compressor , a heat-source-side heat exchanger an expansion device , a heat exchange unit gas port configured to communicate to the utilization-side heat exchanger disposed outside the heat exchange unit , a first heat exchange unit fluid port configured to communicate to the utilization-side heat exchanger , a second heat exchange unit fluid port communicating to the heat-source-side heat exchanger , a third heat exchange unit fluid port communicating to the expansion device , and a heat exchange unit gas communication pipe communicating between the heat exchange unit gas port and the at least one compressor , wherein an outlet of the at least one compressor is connected to an inlet of the heat-source-side heat exchanger by a refrigerant pipe, an outlet of the heat-source-side heat exchanger is connected to the second heat exchange unit fluid port by a first heat exchange unit fluid communication pipe , the third heat exchange unit fluid port is connected to an inlet of the expansion device by a second heat exchange unit fluid communication pipe and an outlet of the expansion device is connected to the first heat exchange unit fluid port by the Z second heat exchange unit fluid communication pipe , and the second heat exchange unit fluid port and the third heat exchange unit fluid port configured to communicate to the thermal storage unit including a thermal storage including or accumulating a thermal storage material , characterised in that the heat exchange unit further comprises a receiver , which is located on the second heat exchange unit fluid communication pipe , particularly between the first heat exchange unit fluid port and the expansion device , wherein the receiver is configured to separate liquid refrigerant and gas refrigerant. <EOS>