
Demonstrating low voltage drives
With rising energy costs and firms’ commitment to reduce carbon footprints, building managers are under pressure to implement energy efficiency measures.
Often, the changes that need to be made for even small energy efficiency gains require a full Capex-intensive refurb and renew project. But there are quick wins to be made, especially when it comes to the performance of motor-driven systems such as HVAC, water pumps, compressors, fans, and other production equipment.
The first place to look is the energy efficiency rating of your motors. Since July 2023, all new electric induction motors installed with a rated output of between 0.75kW and 1MW must meet IE3 efficiency level, and 2-6 pole safe area motors between 75kW and 200kW must meet the requirements of the Super Premium Efficiency class IE4 (or better) in the EU and UK.
However, electric motors can last many years. We often find customers with motors rated as low as IE2 (old Eff1) or even IE1 (old Eff2). Even though they might not need replacing in terms of functionality, swapping them for the latest, high-efficiency motors can deliver payback in months rather than years.
Ideally, all motor-driven systems that require the motor speed to vary, such as HVAC equipment, should come with a variable speed drive (VSD). If your motor-driven unit doesn’t have a VSD, that’s another quick win, with typical energy savings in the region of 25%. If it does have a VSD, there still may be opportunities for fine-tuning. The relationship between a motor and a VSD is crucial for energy efficiency. Performance can vary between brands and can change over time.
It’s also easy for these components to be over- or underspecified, and paired or installed sub-optimally – in these instances, you wouldn’t necessarily notice that they were underperforming. If you haven’t had any diagnostics done on your motor-drive systems, it’s well worth engaging with engineers to see if fine-tuning can be done.
A survey will also help determine if your motors or drives might be nearing the end of their service life, in which case an upgrade or refurbishment will help maintain reliability. Critically, digital diagnostics tools can ensure you catch any opportunities for efficiency gains on an ongoing, real-time basis.
This was a real benefit to a recent customer that used various types of machinery to manufacture products and distribute them to a network of customers and suppliers across the UK and Europe. It needed to spot energy inefficiencies in a fast and scalable way.
Our diagnostics tools helped the customer identify inefficient and high-consumption motors and replace them without disruption to production. We installed more than 100 network analysers, 50 InSite control units, and more than 600 sensors and accessories, which means the customer can now easily understand where energy is being used the most and act accordingly.
The major benefit to the customer is that it can expect to recoup its investment in the first quarter following installation. Projected energy savings total more than 2.5GWh per year – 40% of the site’s annual consumption.
Until energy consumption is measured, saving potential cannot be determined (measure to save). An efficient and accurate system of measuring and monitoring electrical data is important to ensure the success of all initiatives.
Firms such as ABB Electrification have high-precision, accurate energy meters and sensors to capture quality data. This can then be analysed by a BMS or energy-management system to identify opportunities to save energy.
Electrification offers real-time optimisation and control and monitoring, and reporting of energy from Grid to socket. Motor and drive efficiency is one of the simplest ways to improve operational reliability, reduce energy cost and improve building sustainability. When you add analytics providing a real-time window into energy use and offering informed insights, these upgrades make efficiency the ongoing priority. By leveraging these tools, building operators can take steps to streamline their systems and reduce costs.
About the author
Richard Gee is UK sales manager, motors & generators, at ABB Motion