Shoprite Holdings commissioned engineering professional services firm WSP Africa to design a medium voltage (MV) power distribution system for its new Cilmor Distribution Centre to provide reliable, continuous power to three large warehouses, despite regular utility loadshedding issues which were causing an average of two power outages a day.
Shoprite also wanted a system which would limit the company’s environmental footprint, stay within project budget and minimise total cost of ownership.
Shoprite needed an MV switchgear capable of withstanding 10 000 open/close operations, but unfortunately, WSP Parsons Brinckerhoff regional director Saverio Talotti was unable to find switchgear on the market at the time which had been tested to 10 000 operations.
WSP was also shopping for an SF6-free solution. Sulphur hexafluoride (SF6) gas is a dielectric which has been used for years by the electric power industry to help prevent arc flash. Unfortunately, SF6 is also a potent greenhouse gas with a high global warming potential, and its concentration in the earth’s atmosphere is rapidly increasing.
Eaton’s environment-friendly (SF6-free) Xiria E was an ideal solution, but the new design needed to be tested to 10 000 operations. End-of life costs for Xiria E can be up to 25% lower than other equipment (based on the original purchasing cost) and disposal does not pose a threat to human health or the environment.
Eaton Power Systems Engineering in Hengelo, Netherlands, upgraded the Xiria E equipment for WSP, adding a rapid motor switch mechanism and more robust components. It then tested the ruggedised Xiria E equipment to 10 000 operations. These modifications have now become standard on Xiria E switchgear.
“At the time the project began, Xiria E had been tested for up to 5 000 operations, but not to 10 000,” said Eaton Africa electrical solutions and services business development manager Marcel Buckner. “Normal life cycle for such products is around 2 000 operations, so the Xiria E had to be modified to ensure it could withstand 10 000 operations.”
“Eaton’s proposal made the most sense, environmentally and economically – both in terms of upfront costs and total cost of ownership,” says Talotti. “This was a huge difference that had a major impact on project cost.
“Awareness of environmental responsibility is growing in South Africa, and like many companies, Shoprite is watching this carefully,” says Talotti. “End-of-life disposal of switchgear using SF6 is a major concern and a major cost in South Africa.”
Shoprite it expected to continue to benefit from their choice of Xiria E over the lifetime of the switchgear, with the company assured of immediate support for troubleshooting, maintenance and life extension from Eaton’s South African service team.
Moreover, the lower end-of-life environmental impact and disposal cost of Xiria E will contribute significantly to a lower total cost of ownership.