Using energy efficiency audits will help turn the industry from “inefficient to efficient”, says Erich Labuda, President of ABB Motion Services

Motors are everywhere. They are the hidden workhorses of society. They power everything from the fans that keep our buildings hot or cold to the pumps that provide us with clean water and the machinery and conveyors that produce the goods we need every day.

There are millions of industrial electric motors around the world, and the International Energy Agency (IEA) has estimated they consume almost half of all electricity.

Ultimately, these motors will be powered by green electricity as the energy transition progresses. However, developing renewable energy infrastructure is a slow process, and time is running out to achieve our target of no more than 1.5°C global warming.

Making motors more efficient is a more immediate solution that reduces energy consumption and cuts costs at the same time. The IEA has said that energy efficiency would provide a third of all emissions reductions in their Net Zero Emissions by 2050 scenario.

To show industry what it is missing out on, we recently studied the operation of more than 2,000 industrial motor-driven systems in a wide range of sectors and applications.

With the help of energy audits, we found potential for 31 percent average energy savings per motor by upgrading them to more efficient technology. The biggest opportunities were related to motors operating without a variable speed drive (VSD), which enables a motor to match its speed to the demands of the task. Depending on the local cost of energy, this could lead to a return on investment (ROI) of as little as three months. In total, we identified 2.1 terawatt-hours (TWh) of energy savings over the 20-year lifetime of these systems. That’s enough to power 1.25 million European houses for a year – the equivalent of a large city.

Industrial businesses want to be more energy efficient. They just don’t know where to start. According to an ABB survey, 97 percent of industry leaders are willing to invest in energy efficiency, but only 41 percent feel they have the necessary information to act.

Energy audits combat this problem by enabling businesses to pinpoint exactly where their biggest energy savings lie across fleets of motor-driven systems. Businesses can then target systems with the greatest energy-saving potential.

Audits work by gathering operational data from motors to assess their performance and efficiency. This can either be done manually or digitally – similar to the way we wear a Fitbit on our wrist to track our own health and performance. An expert compares the motor’s current performance with the theoretical performance that could be achieved by upgrading to a more efficient system. This could involve resizing or modernising the equipment or adding a VSD. The expert can then calculate expected energy savings and emissions reductions of an upgrade, as well as the expected ROI.

One example is Tarkett, the Swedish flooring manufacturer.  An energy efficiency appraisal in 2022 identified that upgrading 10 of its motors to more efficient technology would boost efficiency from 80 to 95 percent. By acting on these suggestions, the company was predicted to save around 800 megawatt-hours (MWh) annually. That’s enough energy to charge every UK resident’s phone – 68 million smartphones. An expected payback period of 18 months or less was predicted.

Predicted ROI and emissions savings differ between countries due to differences in the energy mix and pricing. Going back to our recent study, the 2,000 motors audited were from a variety of countries. If, for example, all the appraised motors were operating in the UAE, a 2.1 TWh energy saving would avoid 1.5 million tonnes of CO₂ emissions and have an ROI of six months – based on November 2023 data. Alternatively, if they were operating in Germany, this would equate to a saving of 940,000 tonnes CO₂ and an ROI of only three months. These savings would be enough to offset the emissions of a coal plant for two months in Germany and three months in the UAE.

If we extrapolate the findings here to the 300 million industrial motors operating worldwide, then it’s easy to see the potential impact of upgrading all the inefficient ones. It’s no wonder the IEA has said that optimising and replacing motor systems with high-efficiency ones would reduce global electricity consumption by 10 percent.

These findings paint a clear picture. Upgrading to more efficient motor-driven systems is a straightforward and cost-effective way to contribute towards meeting Net Zero targets while also saving money. Making the green choice is often perceived as being the more expensive one overall. But in the case of energy efficiency, that isn’t necessarily true.

Using energy audits to identify the best places for industry to make efficiency improvements should help accelerate our transition to a low-carbon society, and save businesses money at the same time.