Industrial companies are under pressure to cut their carbon footprint and operate in an environmentally sustainable way. Whether driven by customer demand, tightening legislation or meeting their company’s sustainability targets, it is often down to the operations directors and managers to find tactics that will achieve tough decarbonisation targets.
For businesses that operate a lot of electric motors, the energy efficiency audit is a practical tool to support decarbonisation as greenhouse gas emissions are directly related to the amount of energy consumed. Therefore, boosting energy efficiency will immediately cut unnecessary emissions.
An audit can identify areas where electrical energy is being wasted due to issues such as older legacy motors that use more energy than modern high-efficiency technology, motors that have been oversized to handle a theoretical maximum duty that is much higher than the real-world average and places where motors are controlled with mechanical throttling, which is like driving a car with the throttle fully open and using the brake to control the speed.
Improving the energy efficiency of industrial motors
Worldwide, there are around 350 million electric motors in industrial applications. Together, they consume around 70 per cent of all electricity used by industry. Almost every industry relies on motors to power pumps and fans, conveyors, rotating machines, mixers and other equipment.
However, there is room for improvement. A few simple steps – if applied to all motors around the world – could cut global electricity consumption by 10 per cent.
Use motors at their point of peak efficiency
Many motors are sized to meet a plant’s peak output. In reality, this level is rarely needed, meaning that motors are significantly oversized for their average workload. This leads to inefficient operation. Ideally, every motor should be sized so that its peak efficiency point matches its usual operating point. It may be possible to achieve this even just by adjusting a motor’s operating schedule.
Match motor speed to required output
For motors that are already in operation, it is often possible to save energy by adding a variable speed drive (VSD). This precisely matches the speed of the motor to the required output. A VSD is particularly helpful when a motor needs to speed up or slow down to adjust to changing requirements.
Upgrade to high-efficiency technology
In many cases, it may make environmental and economic sense to upgrade to more modern, energy efficient models. The return on investment for the latest high-efficiency models, such as IE5 or ultra-premium efficiency motors, can be very quick. Energy makes up as much as 70 per cent of a motor’s lifetime cost, so operating an inefficient legacy motor is often a false economy.
Using energy audits to identify decarbonisation opportunities
Energy efficiency audits are an essential step to understanding potential energy savings associated with motor efficiency.
Traditionally, these audits require an energy efficiency expert to visit the site in person and manually collect data. They then carry out analysis to identify how efficiently the motors are operating. Finally, they calculate how much energy could be saved by making changes.
Experts can also provide costed recommendations. This enables operational managers to upgrade only the motors with an acceptable payback period or prioritise the ones with the biggest energy savings.
The drawback is that this type of traditional energy audit is a one-time assessment, requires site availability and is labour-intensive, therefore costly. As a result, operators typically only audit their largest motors. Large motors are often the ones to have the greatest potential for energy efficiency savings.
Energy audits are useful for identifying motors that are consuming more power than they need to. They also provide operators with recommendations on how to improve efficiency and cut energy bills. However, only examining the largest motors, can overlook the potential savings from other motors on site. Motors of all sizes can be inefficient, and multiple smaller inefficient motors do add up.
Finding large-scale energy savings with digital energy appraisals
Fortunately, technological advances have reduced the barrier to energy audits. Digital technology has made it possible to carry out in-depth energy appraisals across large fleets of motors at a low cost.
With a digital audit, there is no need to invite an energy efficiency expert to visit the facility. Instead, a site’s own in-house maintenance team can gather motor performance data using technology. The data is then uploaded to the cloud automatically for the expert to access remotely.
Rather than spending time travelling, the energy efficiency expert can now make the most of their time and expertise by focusing on analysing data and recommending potential actions.
Another advantage is that digital systems can gather data continually. This constant digital monitoring enables businesses to take data-driven decisions and upgrade the systems that provide the biggest benefits.
Further, digital energy appraisals can examine all of the motors at a facility, not just the large ones. Digital energy audits can examine hundreds of motors of various sizes, including those in dangerous or inaccessible locations. One example is the ABB’s Digital Powertrain Energy Appraisal, which can be applied to entire fleets of motors, ABB and non-ABB.
“Energy efficiency can be optimized continuously using digital solutions and service expertise to identify the right asset at the right moment to target for improvement,” comments Mari Haapala, Digital Lead for ABB’s Motion Services division. “And these improvements can be small, but can yield great results. The return on these types of investments can be of under a year even.”
Using low-carbon electricity
Improving the energy efficiency of industrial motor-driven systems can help a business to use less energy, and therefore cut its CO2 emissions.
Facilities can also cut emissions by sourcing low-carbon electricity. This involves paying a premium to use renewable energy instead of the local energy mix. A challenge with this is that growing demand is making these contracts scarce. Therefore, it cannot be a facility’s only approach to decarbonisation.
Outsourcing efficiency as an operational KPI
Demand for electricity is likely to double over the next 20 years. The population will continue to grow and industry will electrify sites that were once powered by fossil fuels. Energy efficiency measures are essential to making electrical energy go further and offsetting the need for additional energy resources.
A data-driven approach to energy efficiency audits is an effective solution. These audits enable facilities to minimize energy consumption – and energy bills.
As digital energy appraisals become more widely established, it’s likely that they will support a new business model: energy efficiency as a service. This will see partners like ABB using data to meet energy consumption targets for industrial companies.
Learn more about data-driven energy efficiency appraisals in this white paper: The future is energy-efficient, the future is data-driven.
This content has been produced in collaboration with a partner organisation through our Global Visibility Programme. Our programme helps companies boost their digital presence and strengthen the thought leadership of their experts. Find out more here.
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