Global Perspectives: European efficiency labels for electric motors
Euro motor efficiency: Control Engineering Europe’s Suzanne Gill reports on the effects of June 2011 European motor regulations, relating to the energy efficiency rating of induction motors. Link to more information, including U.S. comparison.
New European-wide regulations took effect in June, affecting manufacturers of low-voltage (LV) induction electric motors. The Regulation (EC) N° 640/2009 states that only efficiency Class IE2 or IE3 motors can be placed on the market in the European Economic Area after June 16, 2011.
As of this writing, a number of interpretation issues were subject of intense debate within the UK and Europe. REMA (Rotating Electrical Machines Association), the UK trade association for motor manufacturers, is updating developments through a related organization, BEAMA, the Federation of British Electrotechnical and Allied Manufacturers’ Associations.
The legislation is applicable for 2, 4, and 6-pole 50Hz and 60Hz motors in the power range between 0.75 and 375kW. The International Efficiency (IE) rating defines how efficiently the motor operates, replacing the previously used EFF 1 and EFF2 designations. (See link to law, below.)
The measuring method for the IE rating is an important differentiating criterion from what has been used in the past, Siemens Drives Technologies Division told CEE. Previously, the stray load losses were taken into account with a fixed 0.5%; these are now precisely calculated. Siemens has used examples of its own motors to indicate what this will mean in practice: A 4-pole 5.5 kW motor for 50 Hz, which previously had an efficiency of 89.2%, now has an efficiency of 88.2% according to the new efficiency calculation method in compliance with IEC 60034-2-1:2007. For the 60Hz type, the efficiency is 89.5%. This change in the efficiency—with the motor technology remaining the same—will be applicable for all motor manufacturers as a result of the modified measuring method.
Making comparisons easy
For plant and machinery builders, this offers the advantage that motors can now be more easily compared with one another. The somewhat higher purchase price for state-of-art technology should have a relatively fast payback time in operation. As a consequence, drive solutions involving a changeover to IE2 motors frequently have a payback time of less than two years, says Siemens.
Dr. Jürgen Brandes, CEO Business Unit Large Drives of Siemens AG, explains what increased efficiency and energy savings can offer in reality. He said, “The cost of an electric motor in operation represents 90% of the overall costs, so it makes perfect sense to further increase the efficiency of these products. Experts have estimated that, worldwide, 120 Terawatt hours of energy could be saved annually by using variable-speed drives and high-efficiency motors.”
In preparation for the new regulations, many motor manufacturers have, for some time, been labeling their motors with the efficiency values according to the IE classification. Siemens has been doing so since 2009. Its rating plates already feature the adapted technical data—such as efficiency, current, IE nomenclature, and nominal voltage.
Motor manufacturer Baldor believes that the new legislation will have huge implications for machine OEMs, and its own research has concluded, somewhat surprisingly, that as many as one-third of OEMs across the EU are still either wholly or partially unaware that new general-purpose ac motors installed from June 2011 must meet the minimum efficiency of IE2, equivalent to the previous EFF1 standard.
“We are calling for all OEMs to start considering the impact of motor efficiency regulations now,” said Robin Cowley, industrial marketing manager for Baldor in the EU. “When they think about the upgrade to IE2 efficiency levels we would also suggest that they consider their strategy for the IE3 efficiency level that is coming down the track too.” Cowley is, of course, referring to the next stages of this legislation, which is being introduced in three stages between this year and 2017. From June 2011 the directive prohibits the sale of motors below standard IE2 efficiency; it will allow only highly efficient IE3 motors for certain larger applications from 2015 and for all applications from 2017.
However, Siemens has stated that in the last two cases an alternative drive solution will also be accepted, which comprises a combination of frequency converter and IE2 motor. In this case, it says, it is not so much the absolute value of the overall efficiency that is so important, but the immense energy-saving potential when using closed-loop controlled drives. This means that even if the constant load efficiency of a frequency converter and IE2 motor is less than the efficiency of an IE3 motor, those responsible for drawing up the EU regulations are expecting huge energy savings as a result of the closed-loop controlled drives. This is especially true for drives used in fluid-flow machines—for example, fans, compressors, and pumps.
Going in the right direction
Steve Ruddell, discrete automation and motion, ABB Ltd., believes that the new IEC motor efficiency standards are certainly a step in the right direction and that they signal the intent to promote energy efficiency by removing the lowest class from the market.
However, Ruddell questions how far the process can go. He said, “With fixed speed IE2 motors due to follow in 2015, we could see IE3 closed down… with IE4 becoming the accepted minimum standard. This is logical, but how far can the technology be pushed? The smallest frame induction motors are at their efficiency limit, with IE2 and no more active materials can be packed inside, which means that the best way to improve the energy efficiency of small IE2 motors is, once again, by applying a variable speed drive. Although other technologies, such as switched reluctance motors and permanent magnet motors, can offer slightly higher efficiencies than induction motors, they also require VSDs. It could be that all motors will one day need to be fitted with a VSD to hit the increasing efficiency levels that are being demanded.”[ABB offers a PDF for guidance on EU MEPS for low voltage electric motors; see link below.]
Driving home the benefits
On the subject of the use of variable speed drives, Colin Hargis, conformance manager at Control Techniques, said: “The general feeling is that, when the legislation moves on to the use of IE3-rated motors, most users will simply opt for the use of an IE3 motor. This is a pity, as the use of an inverter drive to control a motor would offer huge additional energy savings over simply using a more energy-efficient motor.
“In applications where variable speed drives are beneficial, the payback times are now extremely short—as little as one year. However, it always comes down to who pays the energy bill and who pays for the capital cost of the installation. So often we find that the recurrent cost of paying for the power comes out of a different purse, so the best energy-saving solutions are not always implemented. If a return on capital calculation is undertaken it is easy to see that in many applications the use of variable speed drives is massively more cost-effective.
“If you have an application that will benefit from variable speed with an IE2 motor, then it will benefit even more with an IE3 one. Because once you remove some of the extra losses that are no longer being wasted in the motor, you will get an even larger proportionate energy-saving benefit by just turning the speed down.
“If you look at the figures involved in the efficiency improvements given by going from, say, an IE1 motor to an IE2 motor, you are typically talking about a benefit of maybe 2% or 3%. In a pump or fan application, with the addition of a variable speed drive you could save 30%,” Hargis said.
It will always be the end users who will have the final say on their own levels of energy efficiency. So, it really will be up to them to push for the most energy-saving equipment, and accept that this will be at the expense of higher capital cost for the equipment, to ensure they reap the longer term savings of increased energy efficiency.
Calls to go even further
Despite the obvious energy-saving advantages that the legislation will bring to end users of automation technologies who, in recent years, have become much more interested in their energy costs, Marek Lukaszczyk, European marketing manager for WEG, questions whether the legislation goes far enough, noting, “My question is justified on two counts —ATEX motors are excluded from the directive, and the upper limit for the IE classification is only 375 kW. The omission of ATEX motors is probably the most serious problem, as larger motors are intrinsically more efficient anyway.
“There has undoubtedly been a major increase in the number of hazardous areas in industry over the last decade and a commensurate increase in the number of ATEX motors employed as a result of this. In addition, because of the nature of the environment in which they are used, ATEX motors tend to operate continuously, consuming large amounts of energy. I am hoping that the omission of ATEX category motors will be readdressed over the implementation timescale of the directive,” Lukaszczyk said.
Legislative clash or trade barrier?
Alan Bloor, of UK-based Alldrives & Controls, a specialized motor distributor, questions where this staged-introduction legislation places Europe. He is referring to the recently introduced USA Energy Independence and Security ACT 2007 (EISA). He said, “EISA was signed into law in 2007. Based on EPAct92, it updates the mandated efficiency standard for general purpose three-phase ac industrial motors from 0.75 to 375 kW, to the US NEMA premium rating for motors imported into the USA. A key point for all European OEMs is that this legislation applies to motors manufactured or imported for sale in the U.S. after December 19, 2010, and, crucially, NEMA Premium is the equivalent to IE3, which is not due to come into force in Europe until 2015. Importation of motors not meeting EISA requirements is subject to strict penalties, and motor manufacturers are not allowed any leeway.”
Bloor is worried that this could constitute a hidden import barrier, adding, “EISA has already commenced, so unless European OEMs specify ‘NEMA Premium’ motors, export to the USA may be difficult as they will need to source IE3 motors, two years ahead of the directive implementation, and to efficiencies higher than the directive, without any leeway. The alternative is to use U.S. manufactured motors! One has to ask, where is the harmonization?”
Breaking it down
Standard IEC 60034-30—This defines the principle to be adopted and brings global harmonization to energy efficiency classes for electric motors worldwide.
Directive 2005/32/EC—(July 2005) This European Parliament Directive established a framework for setting the eco-design requirements to be applied to “energy-using products.” These products are grouped in “lots.” Motors come under Lot 11 of the eco-design program, as do pumps, fans and circulating pumps.
Commission’s regulation 640/2009 for application of the energy-related product: European Directive Lot 1—This was published in July 2009 and is based on Standard IEC60034-30. It defines the efficiency classes whose use will be mandatory in the future. It specifies the efficiency levels to be attained for machines sold in the European market and outlines the timetable for implementation.
The efficiency levels are:
* IE1: Standard efficiency—Level equivalent to Eff2
* IE2: High efficiency—Level equivalent to Eff1 or “Energy Efficiency” in the U.S. (EPAct 1992), which is applicable from June 2011
* IE3: Premium efficiency—New in Europe or “NEMA Premium” in the U.S. This is applicable from January 2010 or 2017, depending on the power ratings involved.
—Adapted from an April 2011 Control Engineering Europe article by Suzanne Gill, editor, Control Engineering Europe, www.controlengeurope.com.
- How does this compare to U.S. motor efficiency law? See table in the following article: Cover story: Energy-Efficient Electric Motors.
- ABB PDF - Brochure: EU MEPS for LV electric motors: European Minimum Energy Performance Standard for low voltage electric motors sets mandatory minimum efficiency levels for electric motors introduced into the European market. ABB said that from June 16, 2011, onwards, it is not offering, selling, or delivering in any markets globally IE1 CE marked products that fall into the scope of EC 640/2009.