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Motor Efficiency

HEMs - High Efficiency Motors

Among the many pieces of equipment at your facility, electric motors likely make up the majority. They also use more energy than any other piece of equipment. Worldwide, electric motors use 45% of all electricity consumed. Up to 95% of a motor’s costs can be attributed to the energy it consumes over its lifetime, while only around 5% of a motor’s costs are typically attributed to its purchase, installation, and maintenance.

Energy efficiency should be a major consideration when rewinding or purchasing a new motor because the annual energy cost of running a motor is usually many times greater than its initial purchase price.Considerable variation exists between the performance of standard and energy-efficient motors. Improved design, materials, and manufacturing techniques enable energy-efficient motors to accomplish more work per unit of electricity consumed.

Up to 40% Energy Savings

Even when used in large-scale industrial operations, clients implementing HEMs save between 20 and 40% on energy costs, as the motor acts as its own smart load sensor.

Motors on Cruise Control

Just like how a car intelligently adjusts the power drawn from the engine to maintain an optimum speed, HEMs acts as a ‘cruise control’ for motors in your machines!

Full Power in under 1/50th Second

Although only the required energy is used with HEMs , full power is still drawn instantaneously whenever required. Performance will never be compromised, no matter how heavy the load.

Get control of your fixed-speed motors

The loads put on any fixed-speed motor will vary dramatically depending on the requirements on the machine. So why doesn’t the energy usage change with it? Well, with HEMs , it does.

The High Efficiency relates to a class of motor efficiency, and it is the result of legislation by the European Union (EU), USA and other countries regarding the future mandatory use of premium-efficiency asynchronous squirrel cage induction type motors in defined equipment.

This is part of a concerted global effort to reduce energy consumption, CO2 emissions and the effect of industrial operations on the environment, so regulatory authorities in many countries have introduced, or are planning legislation, to encourage the manufacture and use of higher efficiency motors.

The aim is for IE3 for all motors by January 1st, 2017, (for motors from 0.75 to 375kW), with IE2 only in combination with a variable speed drive. Motors are categorized according to a new efficiency class in Europe for 50Hz as International Efficiency ratingas follows:

  • IE1 is a standard efficiency motor
  • IE2 is a high efficiency design,
  • IE3 Premium Efficiency
  • IE4 Super Premium Efficiency for motors that run for more than 4000h per annum

Benefits of High-Efficiency

When most people think about high-efficiency motors, they think about the energy savings and cost reduction of having them in operation. Using energy-efficient motors reduce operating expenses but there are other benefits. As a result, an energy-efficient unit has a longer life than a standard unit.

They reduce emissions and operating costs for a wide range of machinery in domestic, commercial and industrial applications, including HVAC systems, pumps and fans.



Reduced Shock Load
Significantly reduce shock load and peak demand penalties, with real benefits to maintenance
Times Load Current
Starting on-line directly can draw 6-9 times the full load current, but HEMs prevents this
Energy Costs Savings
The average HEMs client will save up to 40% on motor costs

Variable TORQUE & Speed Drives

Electric motors and the systems they drive are the single largest consumer of electricity worldwide, accounting for more than 40% of global electricity consumption. Motors are widely used in both commercial and industrial manufacturing processes, where they can account for up to 54% of total electricity use.

VSDs are used to reduce the energy consumption of motors in commercial applications across the globe, often improving equipment performance and reliability at the same time.VSDs are available for both single-phase and three-phase applications.

The Problem With Motors

Motors lack the intelligence to address three key problems that lead to massive energy wastage, unnecessary carbon emissions and undue wear and tear:

  • Fixed speed motor driven applications like escalators cannot intelligently adjust their torque output to match load changes leading to excess energy consumption.
  • Motors that drive applications like pumps and fans cannot intelligently adjust their speed to match load changes and as such consume more power than they need.
  • When starting, a motor develops more torque than is required at full speed. This high inrush of current can lead to mechanical breakdown and peak demand penalties. To avoid the problems associated with starting, motors are often left running continuously even when they are not being used leading to huge energy waste.



The VSD and VTD Solution

VTD can be applied to fixed speed applications and will dynamically adjust the torque output to meet load requirement without altering the speed (see fig. 1). This leads to substantial savings and is ideal for applications like escalators and many others which run at no/low load for long periods of time. In the right applications, payback is typically under two years.

VSD provides a smooth, step-less acceleration (soft start) of your motors (see fig. 1). This dramatically reduces wear and tear on your system and helps you to avoid peak demand penalties. With a controlled start in place your motors can now be switched off without the fear of re-starting and VSD can be programmed to perform this function automatically.
VSD can be specified to intelligently adjust the speed of your motors to match their variable loading so your motors only consume the power they need. This is a vast improvement over traditional control methods such as throttling (see fig. 2). A mere 20% reduction in speed can lead to energy savings of up to 50%.

Key Benefits

The key benefits with VSDs include:

  • Suitable for Most Applications
  • Reduces heat, noise and vibration
  • Extends equipment life and reduces maintenance
  • Improves power factor quality
  • Reduces energy consumption by up to 50%


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Interested in finding out more? Whether you prefer to contact us by phone, email or via quick contact form, we would be delighted to answer any questions you may have.There are a huge number of ways you can get in touch. We’re happy to answer any questions you may have.

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