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Electric Motor Advantages and Disadvantages

 

A ¼ Horsepower Motor performs the work of two men continuously, more-efficiently, and less-expensively. (And with much less complaining!)

Motors have a number of advantages when compared to engines:

Advantages
  • Low Initial Cost - The initial cost of an electric motor is considerably lower than a fossil-fuel engine with the same Output Horsepower Rating (in nearly every case).
  • Long Life - Because electric motors contain relatively few moving parts, they have extensive operational life spans. For instance, an appropriately selected and maintained electric motor offers up to 30,000 hours of operating life without major repairs. (This is the approximate equivalent of 3½ years of perpetual usage.)
  • Low Maintenance Requirements - Electric motors are durable and have extensive operating life and minimal service requirements.
  • High Efficiency - Electric motors are highly-efficient with ratings that range from 50% to 95% (depending on the motor's size and operating conditions).
  • Automated Control - Automated controls are easily installed to operate electric motors, providing the versatility of automatic and remote Start/Stop functions.
  • No Fossil Fuels - They require NO fuel, engine oil maintenance, battery service, and do NOT freeze in sub-zero temperatures.
  • Labor Cost Savings - Electric motors reduce requirements for labor due to lower maintenance and easier control which ultimately makes production more profitable by reducing costs).
  • Occupational Safety - Motors contribute to the safety of the work environment, emitting little noise, NO exhaust, and without flammable fuels.

There are some disadvantages that accompany the use of electric motors.

Disadvantages
  • Portability - Many larger electric motors are NOT easily portable, and even if a motor is small enough to be portable, consideration must be made for the correct electrical supply and voltage at the new site.
  • Demand Charges - Using high-horsepower motors in applications where they are run infrequently (Low Load Factor) can result in costly electrical demand charges which results in a high cost per hour of operation.
  • Remote Locations - Expensive line extensions are sometimes needed for installation in remote locales where existing electrical power is NOT available.
  • Speed Control - Speed-controlled motors are rather costly and require intricate special equipment that often complicates installation.