It is important for companies to visualize their current stance on carbon neutrality and to measure the effects of their efforts. In this column, we will use a conversation style to introduce how to calculate CO2 emissions of a motor and look at some motors that contribute to CO2 reduction.
Hmmm, CO2...
Hey Vex, what's up?
Ms. Ori! I was thinking about an inquiry from a customer who wants to find out the CO2 emissions of their motor. In order to achieve carbon neutrality for the entire factory, they need the CO2 emissions of the motors used in each equipment.
I see. Carbon neutrality is getting a lot of attention these days. What do you think we need to know about the motor to determine CO2 emissions?
...Is it power consumption (kWh)?
Yes! See, you’ve got it. Then, if you multiply that by the CO2 basic emission factor (kg - CO2/kWh), which is published by electric utilities, you can find the CO2 emissions of the motor.
■ Formula for Calculating a Motor’s CO2 Emissions
The motor's CO2 emissions (kgCO2) = motor power consumption (kWh)*1× CO2 basic emission factor (kg - CO2/kWh)
Uses the CO2 basic emission factor by electric utility from the "List of Grid Emission Factors" of the Ministry of the Environment and the Ministry of Economy, Trade and Industry of Japan.
I see! It should be noted that the "CO2 basic emission factor" differs depending on the electric power company that the customer is contracted with.
Yep, make sure you explain it clearly so that they can check it out. By the way, what kind of motor is your customer using?
It seems to be an AC motor with an output of 200 W combined with an inverter.
In that case, the annual CO2 emissions would be 521 kg.
Power consumption (1109 kWh/year) × CO2 basic emission factor (0.470 kg - CO2/kWh) = CO2 emissions (521 kgCO2)
Conditions
Calculated with daily operating hours at 12 h, operating days per year at 300 days, and the CO2 basic emission factor at 0.470 kg - CO2/kwh.
In case induction motor with a 200 W output and a typical inverter.
Thank you! I’ll reply to the customer.
And, if the customer wants to reduce the motor’s CO2 emissions, you should introduce a brushless motor.
A brushless motor?
That’s right. With the same output of 200 W from a brushless motor, annual CO2 emissions can be reduced to 386 kg under the following conditions. It cam save about 25 % compared to AC motor.
Power consumption (821 kWh/year) x CO2 basic emission factor (0.470 kg - CO2/kWh) = CO2emissions (386 kgCO2)
Conditions
Calculated with daily operating time at 12 h, operating days per year at 300 days, and electricity - CO2 basic emission factor 0.470 kg - CO2⁄kwh.
In case of BMU Series with a 200 W output.
Power Consumption (kWh/year)
Amount of CO2 Emissions (kg/year)
AC Motor + Inverter
1,109
521
Brushless Motor
821
386
By simply replacing an AC motor with a brushless motor, we can reduce CO2 emissions 135 kg per year!
135 kg/year is equivalent to one refrigerator’s worth*2 of annual CO2 emissions.
When you think about it, you can see how effective it is! Different types of motors consume different amounts of energy, so the CO2 emissions also vary! But how is it that brushless motors consume so little energy?
Brushless motors use permanent magnets in the rotor, so losses are reduced compared to AC motors. The big difference is that there is no secondary copper loss. That's what makes them highly efficient and reduces power consumption.
Internal Structure
Loss Type of the Motor
AC Motor
Brushless Motor
That's how the motor rotates so efficiently! And it's small, so it conserves resources as well.
That's right! By the way, EC fans equipped with brushless motors can also contribute to energy savings. Since brushless motors have so many other advantages, how about telling them about our Brushless Motor Proposal page as well?
Thank you very much! I will tell the customer about it right away!
*1
For the respective power consumption of AC motors + general inverters and brushless motors, please contact to the local branch office, sales office, or customer service center.
*2
Assumes a 450 L capacity household refrigerator for a family of 3 to 4 people. (Source: Ministry of the Environment's energy-saving product replacement navigation "Shinkyu-san")
Key Points
The motor's CO2 emissions (kgCO2) can be calculated by motor power consumption (kWh) × CO2 basic emission factor (kg - CO2/kWh)
Brushless motors, which are energy-efficient motors with a high efficiency design, are effective in reducing CO2 emissions
Switching from an AC motor to a brushless motor can reduce annual CO2 emissions by the equivalent of one refrigerator
