International power generator supplier Cummins has recently commissioned one mining site and is in the process of commissioning a further site where both system monitoring and control philosophies, were upgraded.

The mining sites operate and supply 18 MVA and 5 MVA of prime rated generator power respectively.

The upgraded master control systems have been designed to co-exist with the utility provider whereby peak shaving and curtailment control options have been included within the synchronisation operating philosophy.

Both installations will be completed in the first quarter of 2021.

The company has another mining control system upgrade, if awarded, scheduled for completion later this year.

“Cummins engineering and application engineers are well versed and cognisant of the strategic importance of mining total cost of ownership,” Cummins Southern Africa power generation leader Warrick Gibbens tells Mining Weekly.

“Our product is suitable for meeting the strategic intent of both capital expenditure (capex) and operational expenditure projects, delivering savings, while maintaining safety, reliability and availability.”

General consensus in the sector is that mines do not want generators to run independently but would prefer a centralised solution using a Master Controller, he adds.

Mining for Clients

To grow its mining footprint, Cummins is in the process of investing in a hybrid solution at its newly opened facility in Waterfall, Johannesburg.

The system includes a 600 kVA photovoltaic solar installation on the rooftop, which will be capable of synchronising with both State-owned power utility Eskom supply and its current two 1 100 kVA generators.

“We intend to invite prospective clients to our offices, where we can showcase our hybrid solution offering to all interested parties in the mining and engineering sectors,” Gibbens states.

He points out that, although the capex outlay for such an installation might seem high, the return on investment depending on its usage, can be within five to seven years.

“Cummins has also introduced a mobile generator for hard-to-reach and remote areas, which suits the mining sector perfectly”.

He further suggests that an alternative to the traditional permanent power installation solutions, is to supply 1 MVA to 2 MVA of power from generators mounted on a 40 foot flatbed modified trailer, together with its appropriate switchgear, controls and fuel tank.

Synchronising and control options, together with flexible trailing cables, allow for easy equipment connections.

The 2 000 kVA Motivator Power Solution mounted on a trailer can be taken to site for both emergency breakdowns and planned shutdowns.

These mobile generators can help facilitate the operation of emergency ventilation and shaft lifts when the municipal grid shuts down unexpectedly. The generator can be tailored to client specifications to operate a variety of process equipment.

Further, the company has also introduced a 16-valve, 95 ℓ, 3 750 kVA diesel generator – its newest offering to the mining sector.

Gibbens concludes that Cummins generators are highly suited to the South African mining environment owing to their design capability to accommodate high temperatures of up to 55 C, the high altitudes of the Highveld, and the high humidity at coastal regions, and boast snap loads (instant loads) of almost 100%.