AEMT - Association of Electrical and Mechanical Trades

17 December 2018
Copper in a circular economy
I had the privilege of speaking at the annual AEMT conference and was fascinated by the discussion around the changing nature of our global economic structure into a circular economy, writes Paul Dewison of MetalsPlus. It is a topic at the top of the global agenda. In fact, replacing the current take-make-dispose model with a circular economy, which aims to design waste out of the system powered by renewable energy sources, was discussed at length during the recent 24th UN Conference on Climate Change.
Copper in a circular economy
Copper is at the heart of this global agenda. Research conducted by MetalsPlus on behalf of the International Copper Association (ICA) found that copper is a vital material for achieving a circular economy, with an infinite lifecycle and no end phase. Once mined, it can be recycled over and over with no loss of properties making it ideally suited to a wasteless system. It is intrinsic to the design of efficient electrical systems, thus helping us achieve a circular economy.

The motor industry’s drive for efficiency 

How does copper help us achieve energy efficiency? Primarily, it is the best conductor of heat and electricity among nonprecious materials, making it essential for efficient power generation and the delivery of electricity.

The attributes of copper are clearly shown in electric motors. Motor design is being forced to adapt and become more energy efficient. The current energy loss between input and application in motor driven systems stands at 45% (see figure 3). Though much of the loss is from equipment driven by motors rather than the motors themselves, the spotlight still falls on increasing motor efficiency. One reason for this is that motors are typically distinct units that can be targeted more easily by legislation than the diverse array of motor driven systems.

Various options exist for improving motor efficiency. These include the optimization of existing designs, the development of rare earth permanent magnet solutions (REPM) and other non-PM solutions. Considering the UN’s carbon footprint objectives, government regulations now force manufacturers to improve their efficiencies. So now copper’s ability to reduce loss comes to the fore. Without fundamental design changes, improved efficiency usually means more copper use, which is why we are likely to see a rapid growth in demand for this special metal. 

In 2017 alone, motors and generators accounted for 2.13 million tonnes of copper usage. It is found in all six sectors for motors and generators (Figure 1) – from large industrial motors to tiny motors in hand held domestic appliances. In total, the segment accounts for around 8% of all copper use.

The research recently conducted on behalf of the International Copper Association found that copper use in motors and generators should grow to 2.73 million tonnes per year by 2022, rising at a rate of 5% a year (Figure 2). This is an acceleration from the 3.6% growth between 2011 and 2017. The automotive sector is expected to show the most rapid growth, driven in part by a growing popularity of electric vehicles, and followed closely by HVACR (Heating Ventilation Air Conditioning and Refrigeration). 

Copper a building block in energy transition 

Mitigating the effects of climate change is now firmly on the global political and legislative agenda. Not only does current human activity mean rising temperatures, it also means rising sea levels, a more extreme climate, droughts and habitat destruction. CO2 emissions from burning fossil fuel in power generation and road vehicles are the main culprits. Solutions must include generating cleaner electricity, reducing or eliminating road vehicle emissions, and enhancing equipment efficiency to reduce electricity consumption. Copper, it turns out, is intrinsic to all three solutions, and none more so than in motors and generators.

Clean energy generation means the use of renewables – primarily wind and solar. Both are inherently copper intensive, not only in the generators employed in wind farms, but also cables, transformers and other related equipment. For road vehicles, replacing the internal combustion engine with electric traction motors has a direct bearing on copper use, even more so in the lithium-ion battery associated with it. As for energy efficiency, raising motor efficiency by one class, from IE1 to IE2, IE2 to IE3, or IE3 to IE4, can mean an increase in copper use by 20% or more (without a fundamental design change).

Some actions against climate change are market driven, but targets affirmed by the UN COP21 (Paris) Agreement now require government action in legislation as well as by other means. Central to achieving climate change objectives, copper is a major contributor to also achieving a circular economy.

Copper a cornerstone of the circular economy 

The objectives embodied in the circular economy concept are ambitious. The concept centres on the elimination of waste. This is achieved through better design of materials, products, systems and business models. It replaces end-of-life concepts with restoration, seeing the use of new material as ‘leakage’ from what should be a closed system. 

Motor efficiency standards are now firmly on the legislative agenda with the IE3 standard now required (or about to be required) across most countries and motor sizes. The reason for the focus on motors is plain to see; they account for 46% of all electricity consumption (see figure 3). Over 40% of the electricity used in motor driven systems is ‘loss’ (i.e. not translated into motive force). To a lesser degree legislation also addresses the efficiency of the equipment incorporating motors, such as air conditioners and pumps.

While legislation to reduce our carbon footprint is important, circular economy legislation has the potential to take the conservation of limited resources to a much higher level. Wide ranging ambitions are evident in the EU Circular Economy Package and to some degree in the China 13th Five Year Plan. To date, the main focus of legislation has been on waste management and the recycling of materials, but the long-term objective is to go much further. At the production phase this can mean design to minimise material use, the use of low resource impact and recycled materials, and design for repair and long life cycle. Copper should benefit from this development, relative to other materials.

One key attribute of copper is that it is fully recyclable. This, together with the durability of copper-based products, relative ease of repair (shown in the rewinding of motors) and relative low volume of material use, should ensure copper’s continued central role in electrical products, especially motors and generators.

Ultimately, of course, full implementation of circular economy objectives will mean a reduction in all material use, including copper, and especially of new rather than recycled material. In motors, we are already seeing a growing penetration of small highly energy efficient motor designs. High energy density permanent magnets have allowed motor size and weight to be reduced by up to 40% compared to traditional AC asynchronous designs. Reluctance motors offer a similar saving of materials, while the copper-intensive copper rotor motor adaptation of traditional AC asynchronous designs also offers a highly efficient alternative for low material usage. 

Lower copper use in alternative motor designs applies primarily because a given efficiency can be achieved in a smaller motor, with less stator winding. The winding itself can also be leaner. Most motors have distributed windings, but concentrated windings are gaining share, with a significantly lower use of copper in the windings (up to 50%). The use of more sophisticated electronics makes concentrated windings more viable also.

As efficiency levels for motors are ramped up higher, it appears inevitable in the medium to long term that designs that are lean on material use will come to the fore. The materials used will be those that have the best circular economy credentials, so again, copper is set to benefit. 

So, from heavy industry and utility motors to smaller applications such as the automotive sector and domestic appliances, copper is a building block for the transition to a low carbon, circular economy. Thanks to its unique properties, it plays an integral part in many of the products we now depend on to reposition the global economy.


More News from the AEMT
15 October 2019
Following another comprehensive Judging Panel session held at Loughborough University on Thursday 3rd October, the 2019 AEMT Awards Finalists have now been determined.
11 October 2019
The new Honorary President has set out his agenda for developing the Association of Electrical and Mechanical Trades (AEMT) so that it adapts to the changing needs of its members and the markets they serve.
Member News
25 July 2019
Thomas Marks, Secretary to the AEMT, speaks to John White, who looks back at his career with the Sheffield based engineering company, Rotary Engineering, as he approaches retirement.

Twitter Feed

News: Copper in a circular economy