Energy savings with inverter

No need for damper control

Example: The energy savings effect on an office's air conditioning equipment if the operating pattern is as follows: Air flow: 85% for 2,000 hrs, and 60% for 2,000 hrs.Total 4,000 hrs/year. Motor output is 15kW x 1 unit.

  • Under damper (valve) control, the required power is as follows:
    Air flow rate 85% (15kW x 91% x 2,000 hrs.) + Air flow rate 60% (15kW x 76% x 2,000 hrs.) = 50,100kWh
  • If an inverter is used and the motor's rotational speed is controlled, the required power is as follows:
    Air flow rate 85% (15kW x 61% x 2,000 hrs.) + Air flow rate 60% (15kW x 22% x 2,000 hrs.) = 25,900kWh
  • The power saving effect when the power charges are 16.8yen/kWh is
    25,200kWh x 16.8yen = 420,000yen/year
  • The amount of time it takes to amortize the equipment cost if the inverter's cost is 450,000 yen is
    450,000 yen / 420,000 yen = 1.1 years
  • Also, if we let the CO2 emissions coefficient be 0.12 kg/kWh(environmental statistics from the Environmental Department of the Environmental Agency), the annual CO2 reduction amounts to
    25,200kWh x 0.12 kg/kWh = 3,024kg/year

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