Rockwell Automation Inc has, as part of an energy-savings-as-a-service partnership, helped reduce emissions and deliver substantial annual energy savings at the Sibanye-Stillwater Driefontein gold mine in South Africa, it says.

Rockwell Automation and Energy Drive, an energy-efficiency specialist with headquarters in Durban, South Africa, recently signed a memorandum of understanding in which they will collaborate on projects designed so that the resulting energy savings offset any investment in technology and systems required to drive the sustainability solutions.

Designed by Energy Drive, the system at the Sibanye-Stillwater mine is central to the new optimised control solution for the mine’s ventilation architecture. The new efficiencies – which have delivered annual energy savings of more than 55 GWh – will help Sibanye-Stillwater address some core goals of its ESG activities.

The ventilation system’s operational parameters have been remodelled to leverage the capabilities of Rockwell Automation’s PowerFlex® 6000T variable frequency drives. Through optimised control of fan speed and air circulation, this new approach has resulted in an average energy saving of 62% in one shaft and 48% in the other, with another shaft soon to be commissioned, according to Rockwell.

Engineers anticipate that the three upgrades will eventually deliver a total energy saving of about 360 GWh over the term of the contract – equivalent to removing 5,000 South African homes from the grid every month. Notably, it will save 379,000 t of carbon over the period, while significantly reducing water and coal consumption.

“We share a common vision to provide the most efficient and sustainable solutions for customers and the environment,” Tom O’Reilly, Global Vice President, Sustainability, at Rockwell Automation, said. “We are excited to address the rapidly growing needs of our customers with this energy-saving-as-a-service partnership, to help them on their journey to greater sustainability and achieving net zero.”

James Hynd, CEO of Energy Drive, added: “Collaboration is at the core of our business, and actualising sustainability is what drives us.”

Describing ‘actualising sustainability’, Hynd explained that a direct result of the energy savings it delivers is the reduction of CO2, which contributes to clients’ sustainability targets, specifically carbon-reduction targets.

Thomas Malomane, Power Control Business manager, Africa, at Rockwell Automation, explained: “A large proportion of global energy is consumed by electric motors, with HVAC applications accounting for a significant part of this. Many motor-based solutions are either running without any form of motor control or are using outdated technology and practices that do not offer contemporary efficiency capabilities. Our PowerFlex range of variable speed drives undergoes continual development to address modern demands and is a core solution for reducing energy consumption across a huge variety of applications globally.”