An energy management system comprising: a DC voltage bus; a power generation apparatus connected to the DC voltage bus, and outputting generated electric power to the DC voltage bus; a bidirectional DC-DC converter connected to the DC voltage bus, and to which a DC voltage is inputted from the DC voltage bus, or outputting a DC voltage to the DC voltage bus; and an inverter connected to the DC voltage bus, and converting a DC voltage inputted from the DC voltage bus to an AC voltage, wherein each of the power generation apparatus, the bidirectional DC-DC converter, and the inverter includes a voltage detection portion (221, 31, 41) configured to detect a voltage of the DC voltage bus, and a switching control unit (226, 36, 46) configured to carry out switching control such that a detection voltage that the voltage detection portion (221, 31, 41) detects matches with a target value, the energy management system further comprising: a calibration value setting unit configured to compare the detection voltages detected by the respective voltage detection portions (221, 31, 41), and to set a calibration value to a highest detection voltage; and a calibration unit (224, 34, 44) configured to calibrate the detection voltages of the voltage detection portions (221, 31, 41) excluding the voltage detection portion (221, 31, 41) which detects the highest detection voltage with the calibration value. a DC voltage bus; a power generation apparatus connected to the DC voltage bus, and outputting generated electric power to the DC voltage bus; a bidirectional DC-DC converter connected to the DC voltage bus, and to which a DC voltage is inputted from the DC voltage bus, or outputting a DC voltage to the DC voltage bus; and an inverter connected to the DC voltage bus, and converting a DC voltage inputted from the DC voltage bus to an AC voltage, wherein each of the power generation apparatus, the bidirectional DC-DC converter, and the inverter includes a voltage detection portion (221, 31, 41) configured to detect a voltage of the DC voltage bus, and a switching control unit (226, 36, 46) configured to carry out switching control such that a detection voltage that the voltage detection portion (221, 31, 41) detects matches with a target value, the energy management system further comprising: a calibration value setting unit configured to compare the detection voltages detected by the respective voltage detection portions (221, 31, 41), and to set a calibration value to a highest detection voltage; and a calibration unit (224, 34, 44) configured to calibrate the detection voltages of the voltage detection portions (221, 31, 41) excluding the voltage detection portion (221, 31, 41) which detects the highest detection voltage with the calibration value. a calibration value setting unit configured to compare the detection voltages detected by the respective voltage detection portions (221, 31, 41), and to set a calibration value to a highest detection voltage; and a calibration unit (224, 34, 44) configured to calibrate the detection voltages of the voltage detection portions (221, 31, 41) excluding the voltage detection portion (221, 31, 41) which detects the highest detection voltage with the calibration value.