Eco-design of Electric Motors

EU regulation 2019/1781 lays down eco-design directives for electric motors and variable speed drives. Effective October 2019, this regulation defines labeling guidelines and benchmarks for electric motor efficiency.

What Qualifies as an Electric Motor?

International trade in electric motors occurs at high volume, with global exchanges in 2020 clearing over USD 100B worth of volume. Electric motors and variable speed drives (VSDs) occupy important roles across a range of different marketplaces, and their applications vary widely. Therefore, a large portion of (EU) 2019/1781 is devoted to building a precise definition of motors that fall under its statutes, as well as those motors that are specifically excluded from the definition.

Additionally, the regulation provides guidelines for the eco-design of electric motors. These points are concerned with the construction, operation, and output of motors and VSDs. Some of these requirements are listed as a range of values, due to the significant variabilities in the design and application of motors.

Quick Reference Guide: Which devices fall under (EU) 2019/1781?

Electric Motors	Variable Speed Drives
The motor contains no brushes, commutators, slip rings, or electrical connections to the rotor. The motor is rated for operation at 50, 60, or 50/60 Hz sinusoidal voltage. The motor has two, four, six, or eight poles. The motor has a rated voltage of between 50 and 1000 V. The motor has a rated power of between 0.12 and 1000 kW. The motor is rated for continuous-duty and direct on-line operation.	The VSD uses a three-phase input. The VSD has a rated voltage between 100 and 1000 V AC. The VSD has only a single AC voltage output. The VSD is rated for operation using one motor (as defined here) such that it operates at a rated power between 0.12 and 1000 kW.

Important Exceptions to the Definition

Clearly, electric motors (as a class of products) are broad and complicated to define. Devices may be designed for specific applications, for use in extreme operating conditions, or require nonstandard sizes or shapes. Importantly, many of these specialized motors and VSDs may be exempt from regulation or else governed by a separate set of guidelines.

These devices are likewise governed according to their construction and their application. Note that most exemptions are designed for motors fully built into other products, or those designed to accomplish very specific and intensive work. Therefore, product specifications might include a seamless build or exceptional durability, such that the motor becomes an integral part of the parent product. In this case, the scope of product environmental regulation shifts to the product as a whole.

Quick Reference Guide: Which devices do not fall under (EU) 2019/1781?

Electric Motors	Variable Speed Drives
that are exempt from 2019/1781 section 1, and points (1), (2), (5) to (11), and (13) of section 2 of Annex I:	that are exempt from 2019/1781 section 3, and points (1), (2), and (5) to (10) of section 4 of Annex I:
Motors containing an integrated brake that makes efficiency testing difficult Motors containing an integrated VSD whose performance cannot be independently measured Motors Integrated into another product completely, so that it can’t be removed and tested independently Motors designed to operate exclusively when immersed in liquid at 4000m or more above sea level at operating temperatures above 400^oC where the ambient air temperature is lower than -30^oC or higher than 60^oC. in cordless or battery-operated equipment.	VSDs that use sinusoidal input current during operation Regenerative drives Any VSDs that: are integrated into another product completely, so that they can’t be removed and tested independently consist of a single cabinet comprising VSDs that, themselves, conform to this regulation

Eco-Design Requirements for Electric Motors

After confirming that a motor falls under eco-design regulations, it receives a corresponding minimum energy efficiency value. This parameter depends on the motor’s construction, operating frequency, rated voltage, and output power. The regulation document provides a selection of standard rated power values and ranges; depending on the number of poles in the motor, the regulation assigns a value indicating a mandatory minimum performance.

Finally, the resulting values are tabulated according to IEC efficiency classes for 50 and 60 Hz operation. Motors with nonstandard power ratings can have their classes and minimum efficiencies calculated, rather than assigned by lookup. Be aware that the rules applied to such motors depend on their operating frequencies: 60 Hz motors use the efficiency of the next highest or next lowest standard power rating (whichever is closer), while 50 Hz motors can use the formula

Other important values, like loss parameters and interpolation coefficients, are assigned to motors according to their construction and power transfer characteristics.

VSDs follow a classification process that is much like electric motors, although they are given their own set of specific guidelines and key parameters.

An Exciting New Motor Comes to Market

Let us consider a case study: a modern industrial motor targeted at large freight hovercrafts is designed and fabricated in the Czech Republic. It is replaceable, follows a six-pole “high torque, low rpm” design methodology, and has a maximum rated power of 75 kW.

Since the motor is destined for the North American market, it is intended to operate at 60 Hz. Together, all of these parameters designate the motor at an IEC efficiency class of IE3 at the lowest.

Therefore, 2019/1781 stipulates a minimum efficiency of 95.0% at full operation (Annex I, Table 3b).

Fans Driven by Electric Motors

In addition, motors are frequently used to drive fans for cooling or ventilation purposes.Consequently, a fan driven by an electric motor that uses an input power between 0.125 and 500 kW may be subject to additional ecodesign regulations under (EU) No 327/2011.

Quick Reference Guide: What is exempt under (EU) 327/2011?

Any fans integrated into:	Any fans designed to be operated:
laundry and washer dryers with max input power of less than 3 kW kitchen hoods with less than 280 W of the total input power attributed to fans products with a single electric motor (at 3 kW or less) whose fan is fixed on the same shaft and drives the main functionality	around highly abrasive, toxic, flammable, or explosive substances specifically for emergency use at short-term duty in ambient temperatures above 65^oC while moving gases at temperatures higher than 100^oC using a power supply of more than 1000V AC or 1500V DC

Fortunately, fans are classified similarly to the motors that drive their motion. That is, they must uphold a minimum performance that depends on their construction, range of rated power, and any ducts or fittings attached to the fan during operation. In almost all cases, a fan’s target energy efficiency is expected to follow a logarithmic relationship with its output power P, via

η = A ∙ ln(P) – B + N

source: (EU) No 327/2011 Annex I Table 1

where the parameters A and B depend on the type of fan and its configuration. For example, a mixed-flow fan has the following energy efficiency profiles under low- and high-power operating modes:

Beyond Eco-design of Electric Motors

After ensuring compliance with ecodesign regulations, suppliers may also need to consider other environmental requirements. Additional legislation may require further groundwork, depending on a product’s intended market. For example, the following regulations also apply in the EU and elsewhere:

RoHS Compliance – Restriction of Hazardous Substance regulations in place worldwide
REACH-SVHC – Restrictions on Chemicals Substances of Very High Concern
WEEE – Electronic waste directives and device life-cycle guidelines
POP-Halogen Free Compliance – Restrictions on Persistent Organic Pollutants
EPREL – Additional EU product labeling requirements
TSCA-PBT – Toxic Substances Control Act enforced by the EPA in the United States
Proposition 65 – California’s growing list of harmful consumer substances

If you need help navigating eco-design regulations for an electric motor or VSD you are developing, our experts at Enviropass can offer step-by-step guidance for all your environmental needs.