What are the benefits of high efficiency motors, IE2, IE3 and IE4?
When buying a motor–driven system, it is much more important to consider its running costs that its purchase price. To only compare purchase prices is a false economy and overlooks the considerable financial benefit of lower lifetime costs. Any capital saved by not investing in the most efficient motor and control system can be lost many, many times over in the additional energy consumed by the system during its operation life.
Whether it is being used for pumps, fans, compressors, conveyors, ventilation, refrigeration, fluid handling or cooling; the energy cost of a motor-driven system will be significant compared to its purchase cost. However, while the capital budget often gets a lot of scrutiny, and purchase cost is a major factor in the decision process; the energy cost of a system is rarely quoted or requested. When you buy a new car, the fuel consumption figures are quoted on advertisements and promotional literature and, in many cases, are used as a marketing tool to help sell the car. Taking a typical saloon car, the fuel cost over ten years would amount to only 20% of the original purchase cost, even though many owners wouldn’t keep the car that long. The initial purchase is an important factor, yet miles-per-gallon are still taken into account.
In the case of a typical electric motor, the energy cost over ten years is more than 25 times the purchase cost, and many businesses will keep the system operating a lot longer than that.
You would think that the efficiency of the system would be the primary concern in this case. The comparison is illustrated in the graph, where it becomes very obvious that energy efficiency should be the major decision factor when buying a motor-driven system. If the motor-driven system could be made 20% more efficient, then it would save more than five times its purchase cost in energy. In many systems, intelligent motor control can be used to vary the motor’s speed or switch it off when it is not needed to save this 20% or more. Any investment in saving energy in such a system will usually pay back quickly and continue to make savings throughout the life of the motor.
By comparison, a 20% fuel economy in a car is rarely a realistic option, but even where it is possible, it is only going to save 4% of the purchase price.
Anyone who buys or uses electric motors should always pay attention to their energy consumption, as it will outweigh the purchase cost several times over. You should be asking yourself:
Is there a more efficient motor that will use less energy?
Can the motor be controlled by a VSD or automated starter to reduce the energy consumption?
Has the whole system been designed to optimise energy efficiency?
The significant energy consumption of a motor compared to its purchase price means that any way of improving the efficiency can repay the investment many times over. This applies equally to installed motors and to new purchases. Many of the systems operating in industry and business would benefit from retrofitting some form of control system to reduce energy consumption. Don’t just ask how much it costs to buy but how much it costs to run – and how much could I save?
Since August 2012 only IE3 efficiency rating motors attract government ECA (Enhanced Capital Allowance) benefits. IE2 Motors whilst still legal to be bought and sold are not listed on the governments website which lists all acceptable high eligible equipment and no longer attract the ECA benefits for motor buyers.
Quantum Controls are largest stockist of IE3 efficiency ABB Motors in the UK, winner of 3 national energy awards in last 24 months meaning we understand the true cost of all motor driven systems, call us today for best advice, competitive pricing and FREE motor delivery anywhere in the UK 0330 9000 247 – [email protected]
Answer by Steve Brambley, Deputy Director, Gambica