AC motors efficiently convert electricity into rotational motion, driving industrial equipment (pumps, conveyors), household appliances (fans, refrigerators), and HVAC systems.
Industrial Equipment
The global industrial AC motor market was valued at more than $58 billion in 2023 and is expected to expand at a compound annual growth rate of 4.8% through 2030. The conventional three-phase asynchronous motors used by most industries for production have an average efficiency ranging between 85% and 96%, while for high-efficiency motors, the range goes up with IE3 and IE4 standards above 97%.
Besides, high-efficiency AC motors save a medium-sized factory running 6,000 hours yearly about 70,000 kWh electricity, which means about 70,000 RMB due to reduced consumption of electricity. Further, on average, one standard AC motor needs an annual maintenance of about 200 RMB while that of DC motors is likely to be two or three times more.
The hoisting equipment in mining operations is normally equipped with AC induction motors up to 1,000 kW. Small AC motors in the range of 0.75 kW to 2.2 kW are used in industrial fans. Each motor costs only 300 to 800 RMB, so there is big demand for such motors among small and medium-sized enterprises.
The energy efficiency of such motors generally exceeds 93% due to the optimization of their designs, therefore reducing energy consumption in sewage treatment below 0.5 kWh per 1,000 cubic meters of wastewater. These technological applications save approximately 100 million kWh of electricity annually for a large city, which is equivalent to reducing nearly 100,000 tons of carbon dioxide emissions.
Home Appliances
More than 75% of the drive components utilized in appliances were AC motors in 2022, with the yearly consumption in washing machines, refrigerators, and air conditioners having crossed over 500 million. The induction motors are the most prevalent kinds of AC motors available within the market. In the market, their power normally ranges between 200 watts and 500 watts.
A single cycle of a washing machine, equipped with a regular single-phase AC motor, may use up approximately 1.2 kWh and can run for around 30-90 minutes. High-efficiency AC motors can cut the general consumption of washing machines by 15%-20%. It is assumed that, if a family washes clothes five days a week, then using a high-efficiency AC motor will save 100 kWh every year and be able to lower the cost of electricity by about 80 RMB.
A general 1.5-horsepower air conditioner has a compressor motor of approximately 1,000 watts and a fan motor of 50 to 100 watts. Inverter air conditioners usually have an EER greater than 4.0, which may reduce power consumption by 30% compared to traditional fixed-speed air conditioners.
Compressors used in refrigerators generally operate on 60 watt to 150 watts of electricity by transferring heat through compressing refrigerants. High efficiency compressors save about 10 percent energy consumption, yet providing the same cooling effect. A 300-liter energy-efficient refrigerator consumes about 150 kWh electricity annually while a conventional refrigerator may use up to 200 kWh.
Ordinary household fans require 40-60 watts of motor power. Typically, the velocity of the air flow from the fan is modulated by changing the operating speed of the AC motor. A fan that runs for about 8 hours per day uses roughly 10 kWh in a month. High-efficiency, low-noise motors in new designs increase the average life of electric fans to 8 years and reduce operational noise levels by 20 dB.
The power of a household vacuum cleaner is usually within the range of 1,000 to 2,000 watts, which supplies strong suction in order to eliminate fine particles from carpets or floors. The high-efficiency vacuum cleaner increased cleaning efficiency by 25% compared to standard ones, cleaning as much as 30 square meters per minute, which remarkably shortened the cleaning time.
The internal motor is typically rated between 300 watts to 600 watts and reaches speeds of more than 10,000 rpm.
The average pump motor installed in a 50-liter capacity tankless water heater operates on about 30 watts and runs for approximately 500 hours yearly, which equates to less than 15 kWh of electricity consumption. It increases the efficiency of heating and reduces waiting time for hot water consumption by a large factor.
Smart robotic vacuums generally use small, high-efficiency AC motors. The motor power is usually from 20 W to 40 W. Because of smart path planning and obstacle recognition technologies, together with high-efficiency motors, more than 98% of the area can be covered by robotic vacuums, cleaning up to 150 square meters on one charge.
Electric Vehicle Motors
In 2023, the global market for AC motors in electric vehicles reached a value of $38 billion and is expected to continue a growth rate of 12.3% annually through the year 2030. Generally, the electric vehicle is having motor output power in the range of 50 kW to 150 kW, and peak torque more than 300 Nm. The Tesla Model 3 has a motor power at the rear axle of 211 kW, while its peak torque is 420 Nm, offering a strong performance and making the car accelerate from 0 to 100 km/h in just 5 seconds.
Traditional internal combustion engines can only convert about 25% of the input energy into useful work, while AC motors in electric vehicles can convert over 90% of the input electrical energy to mechanical energy. For example, the motor efficiency in the Nissan Leaf reaches 94%, which means for every 100 kWh of electricity consumed, close to 94 kWh is converted to driving energy.
As known, the use of high-efficiency motors reduces directly the energy consumption of an electric vehicle. In this electric vehicle with 400 kilometers, energy consumption is just 0.15 kWh per kilometer. Therefore, with every electricity cost being 0.6 RMB per kwh, that amounts to less than 0.1 RMB.
A 50 kW motor produces approximately 2 kW of heat at full load operation; if not dissipated in due time, it lowers the efficiency or can even damage it. Regenerative braking systems are able to recover up to 20% of energy. In other words, for an electric vehicle with a range of 500 km, one can travel an extra 100 km on one charge.
Generally, the 50 kW PMSM weighs from 40 up to 60 kg at a diameter from 30 up to 40 cm. During 2015, on average, the cost of one motor of electric vehicles amounted to US$5,000; while in the year 2023, these reduced to an approximate value of US$2,000. Accordingly, it has been foreseen that the cost will decrease below US$1,500 with the increases in production scales and technology for the year 2030.
Air Conditioning Systems
In 2023, the global sales of air conditioning equipment reached 150 million units, and over 90% of the air conditioning systems use AC motors. The fan motor of indoor units generally ranges from 50 watts to 100 watts, and its operating speed has a direct impact on the cool or warm air distribution.
High-efficiency fan motors can improve indoor airflow uniformity by 15% and greatly enhance the user experience. An air conditioner with a rated power of 1.5 horsepower consumes only about 0.5 kWh of electricity daily for running its indoor unit fan for 10 hours, accounting for about 10% of the total energy consumption of the air conditioner.
The compressor of the outdoor unit is the core of the air conditioner, and its motor power is generally between 500 and 1,500 watts. Under partial load conditions, air conditioners with inverter compressors can achieve energy efficiency improvements of up to 30%, allowing the overall annual energy efficiency of the air conditioner to reach more than 5.0 and meet the national first-level energy efficiency standard.
For a 2,000 square meter commercial building, its center air conditioning generally includes several sets of pumps and fan motors at 7.5~15 kW in specification, running for 12 hours every day. The total consumption can amount up to 900 kWh per day. With energy-saving high efficiency motors and advanced optimization of controlling algorithms, a saving of 15% can reduce the consumption close to 50,000 kwh of electricity consumption per year.
The general range for the fan motor of a fresh air system is from 200 W to 500 W, which can provide 500 to 1,000 cubic meters of fresh air per hour. For a 100-square-meter residential space, running a fresh air system for 8 hours daily can renew the indoor air fully twice, with energy consumption of only about 4 kWh.
For an air conditioner, a good-quality AC motor may last more than 10 years, but if routine maintenance is done, it may even last beyond 15 years. In a commercial central air conditioner system, about 20% of the total cost of maintenance involves motor maintenance. Motor maintenance per year may amount to about 5,000 RMB.
One can imagine that in a 3,000-square-meter cold storage warehouse, several compressor motors are above 30 kW. Running 24 hours day and night, it consumes several million kWh every year. So far, permanent magnet synchronous motors that are 10% more efficient than their induction motor predecessors have been adopted by many cold storage warehouses. It saves about 200,000 kWh every year, corresponding to an electricity cost of about 200,000 RMB every year.
Agricultural Irrigation
More than 80% of power machinery applied in irrigation systems of agricultural sectors all over the world uses AC motors. It is especially higher in developing regions. For instance, there are more than 10 million AC motors running on agriculture irrigation equipment with a total power of more than 20 million kW in 2022 in India, serving more than 70% of its arable land area.
The most commonly applied AC motors for farm irrigation are those applied for pumps whose power differs between 1.5 kW and 100 kW according to the water supply size. A regular irrigation motor at 7.5 kW has the capacity to pump up to 120 cubic meters of groundwater per hour, with a sufficiency to irrigate approximately 20 acres of farmland.
This motor uses approximately 60 kWh of electricity every day for 8 hours/day. Using the rate of electricity at 0.6 RMB per kWh, the operating cost is 36 RMB per day, which saves so much labor cost for agricultural water use. A sprinkler standard uses a 5 kW AC motor and is able to pump up to 60 cubic meters per hour; it keeps the water pressure at about 3.5 bar.
A 1.5 kW-rated motor can run for 10 hours a day to support the entire precision drip irrigation required for 10 acres; this is remarkably achievable with water consumption of mere 10 cubic meters per hour. Meanwhile, high-quality agriculture irrigation motors had a mere failure rate of only 0.8% after a run of 3,000 continuous hours operating, while this goes as high as 5% for conventional motors.
The irrigation system with VFD technology can raise the motor efficiency to over 90% and enable the output power of the pump to automatically adjust according to the actual demand. It saves up to 30% in annual electricity costs. In this way, for a farm of 100 acres, the electricity expenses can be reduced from 30,000 RMB to 20,000 RMB annually.
Most of the center pivot irrigation systems in the United States Midwest are equipped with motors from 30 kW to 75 kW, irrigating areas in excess of 500 acres. The system could irrigate as high as 500 cubic meters per hour. After introducing such high-power and highly efficient equipment, the average water use per acre per year went down by 100 cubic meters while crop yield was improved by over 5%.
The solar-powered irrigation system with an installed capacity of 10 kW can run its AC motor for 6 hours per day, which will be providing irrigation support for 30 acres of land. In 2022, approximately 85% of the water pumps across the world were powered by AC motors, numbering 300 million kW in total installed capacity, as municipal water supply and industrial water systems account for the major market share.
There, generally, a number of AC motors are applied in the main water-pumping equipment in a municipal water supply station serving 1 million people, rating from 500 kW to 1,000 kW, while the total amount of water supply may amount to 200,000 cubic meters every hour. Operating for 16 to 20 hours daily, the energy consumption of such motors accounts for 60% of the operating cost of the whole water supply system. High-efficiency motors can reduce energy consumption by 10%-15%, saving more than 10 million kWh of electricity annually for the city.
A typical agricultural pump station is normally equipped with a 50 kW motor that can pump 600 cubic meters of water per hour, sufficient to meet the needs of 100 acres of farmland. Working Costs: AC motor-driven pumps have the operating cost lowered compared with traditional diesel-driven pumps by roughly 40%; for example, an hourly charge for operating such a diesel pump amounts to almost 80 RMB, where for an AC motor pump that it takes less than 50 RMB – an economically serious relief for peasants.
A factory producing 1 million tons of chemicals annually uses over 200 AC motors to drive pump equipment for liquid transfer, with a total installed capacity of 5,000 kW. These pumps efficiently transfer acids, alkalis, and high-viscosity fluids, with flow rates ranging from 10 cubic meters to 500 cubic meters per hour, precisely meeting production needs while reducing the economic losses caused by downtime.
The motors of major pump stations have power over 2,000 kVA in the Shanghai Flood Control and Drainage System. Their hourly drainage can reach more than 100,000 cubic meters. It can work for dozens of hours continuously in typhoon seasons, which has relieved over 90% of the risk of urban waterlogging.
A common deep-well pump is normally equipped with motors ranging from 30 kW to 150 kW, and the lifting height is over 300 meters. They are widely used in water resource development in arid regions. Seawater desalination pumps mostly use AC motors with a power rating of 500 kW to 2,000 kW. These can process 100,000 cubic meters of seawater per hour into potable fresh water.
An average oil pipeline station consumes between 3,000 kW and 5,000 kW with each capable of pumping in excess of 5,000 cubic meters of crude oil in an hour. Adopting high-efficiency permanent magnet synchronous motors reduces energy consumption by over 10% as compared to the traditional asynchronous motors. A pipeline system pumping 200,000 cubic meters of crude oil a day can cut its electricity cost by more than 2 million RMB per year.
