Combined with binding net zero commitments, those costs mean energy efficiency is no longer a ‘nice to have’ and could be vital for companies’ future survival. Solutions are needed – and IR Power believes it has a way to find and reuse an “invisible” waste stream within factories.
Described as “like regenerative braking in electric cars, but for industrial equipment”, the Aberdeenshire firm’s Regenerative Energy Network (Ren) is a retrofit energy recovery system for factories.
Large motor-driven industrial machines frequently decelerate as part of normal operation. During deceleration, the motor acts as a generator and returns energy to a DC link. In most factories, that electricity is simply sent to banks of resistors, and ends up as heat.
“The key discovery for us was motor-driven machines in factories were universally wasting energy,” said founder and managing director Richard Bradshaw to Professional Engineering earlier this year. “The waste is invisible… To the management and the plant managers, the idea that there is much waste going out as heat is a surprise to them. What was invisible, we make very visible.”
The company does so through installation of its ‘plug-and-play’ systems, which use active front end converters to convert recovered DC energy into synchronised AC power for reuse within a factory. The system can recover as much as 10-20% of a factory’s total power consumption, the company claims.
The Ren can be used with machines in a variety of industrial processes at different scales, from making paper and packaging up to heavy work like forming metal. It offers an alternative to replacing industrial machines, which can have 20-30 year lifespans, according to IR Power. Even upgrading drive systems can cost £1m or more.
“There’s a lot of deployed equipment out there without energy efficiency equipment. And even today, people buy new things without the embedded energy efficiency modes,” Bradshaw said.
“There are some conventional ways of dealing with that – you can upgrade the machines, but that's a big ask for a company. That could be a million-pound or more project… it isn’t palatable.”
The company instead developed the Ren system, which routes waste energy onto a single network, from which it can be deployed. The nondescript cabinets are designed to integrate machines with smaller amounts of waste alongside larger machines with much more waste energy.
On large automotive press lines, consisting of machine clusters cycling every six seconds, the approach can reportedly recapture 10-20% of total electricity consumption. That represents up to £50,000-100,000 in annual savings per machine cluster, an announcement said.
The system is designed to work with machines from various brands, with different power ratings and duty cycles. Machines’ original braking resistors and protection systems remain in place, with no changes made to machine control logic or torque control loops.
“This is about centralisation, having a centralised network where we can plug and play some different technologies,” Bradshaw said. “Having this centralised network, which is agnostic to drive manufacturers, would mean that we could plug in more machines. So we could plug in a Siemens machine and an ABB machine, and so on and so forth.”
Recovered energy can be immediately consumed by other loads in the facility. Where braking events are short and high power, short-duration storage can also be connected to increase overall capture efficiency. The Ren can include conventional capacitors and supercapacitors, IR Power’s proprietary flywheel energy storage system and other off-the-shelf energy storage technologies.
“Storage is deployed only where it improves utilisation, performance or economic return,” a spokesperson told Professional Engineering.
The spokesperson also stressed operational resilience – if regenerative energy exceeds the Ren’s capacity, it is designed to divert excess energy back to the existing braking resistors, with machine operation continuing.
A rental model means manufacturers pay nothing upfront and only pay monthly fees based on measured saving, which could be particularly important given the volatility of energy prices.
“There are some other global ‘macro-things’ happening,” Bradshaw said. “Data centres, or other industries that consume a lot of energy, often co-locate in the places that our customers are. There’s not necessarily an infinite supply of energy.”
Sustainability is a consideration “but what overrides most things is cost… [companies] are operating in global markets, they're competing against the machine in the next city, or even next country, or other side of the world, and so they need to show that they're being cost-effective.”
The company is beginning commercial deployments this year, prioritising press applications including tier-one automotive and construction materials manufacturing.
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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.