23 Jul 2024


Electricity used by motor-driven systems could double in 20 years

If steps are not taken to improve the efficiencies of systems driven by electric motors, electricity consumption by motors globally could almost double to 13,360TWh per year by 2030 – equivalent to emitting 8,570 million tonnes of CO2 – warns the International Energy Agency (IEA) in a major new report. It adds, however, that raising the efficiency of electric motor-driven systems (EMDS) by 20–30%, coiuld cut the demand for electricity by 10%.

According to the IEA, EMDS – which include mechanical as well as electrical drivetrain components – account for 43–46% of global electricity consumption. This is more than twice as much as the next-largest user, lighting. “End-users now spend $565bn per year on electricity used by EDMS,” the report’s authors say. “By 2030, that could rise to almost $900bn.”

The 132-page report, Energy-Efficiency Policy Opportunities for Electric Motor-Driven Systems, recommends a wide-ranging package of policies to help governments tap the huge potential for energy savings in EDMS.

If the best available motors were used, the IEA estimates that motor electricity consumption could be cut by 4–5%. If these motors were linked to other improvements in the drivechain, including more efficient gears and belts, the savings could rise by a further 15–25%.

By adopting the best technologies, the world’s electricity demand could be cut by 3,890TWh a year by 2030 – reducing CO2 emissions by 2,490Mt. This would be equivalent to about half of the CO2 emitted by the US in 2008.

The IEA suggests three main routes to achieving these savings:
•  using properly-sized, efficient motors;
•  installing variable speed drives, where appropriate; and
•  optimising complete systems, including gears and transmissions, pipes and ducts, and end-use equipment such as fans, pumps and traction systems.

However, these measures will need policy interventions such as the imposition of minimum energy performance standards (MEPS), which already apply to more than a third of the world’s population. If every country adopted MEPS for industrial motors, the annual electricity savings by 2030 would be around 322TWh, the IEA estimates.

The MEPS should also apply to as many types and sizes of motor “as it is feasible to address,” the IEA adds, suggesting IE3 as the minimum efficiency level. The measures should not be restricted to mid-sized asynchronous AC motors sold as separate components, it emphasises.

The savings could be even larger if all aspects of motor-driven systems were optimised. The IEA suggests that some “fundamentally inefficient” technologies such as wormgears and V-belts could be regulated out of the market.

The Agency says it is “essential” to scale up the resources committed to “realising the vast savings potential of optimised EMDS”. It adds that the energy efficiency of EMDS has been “relatively neglected” compared with other sustainable energy options. “Nowhere do such systems currently benefit from the scale of support that is offered to sustainable supply-side options,” it complains.

According to the IEA, if a “broad-based and rigorous” policy package were put in place, global electricity savings could be 24,000TWh by 2030, generating cost savings worth $1.7 trillion, and these savings would come at less than the cost of supplying the energy.

The IEA has also produced a second report, called Walking the Torque, which proposes a regulatory workplan for reducing the electricity consumed by EDMS globally by 5% by 2030.