Solar plant, battery storage enhance sustainability in tailings

In an effort to reduce its reliance on grid power and improve sustainability metrics, gold mining company DRDGOLD has completed a 60 MW solar PV power plant at its Ergo tailings reprocessing plant, on Gauteng’s East Rand, with 20 MW now operational, as well as commissioning a 160 MWh battery energy storage system.

The facility generated more than 13.1-million kWh of energy during the 2024 financial year, amounting to 10% of Ergo’s consumption, the miner reported in August.

The transition to renewable-energy use is an integral part of DRDGOLD’s approach to decreasing its environmental footprint and impact, says CEO Niël Pretorius, adding that the miner’s decarbonisation strategy will see the proportion of renewable energy used rising to about 14 000 MWh/month, equating to about half of Ergo’s overall energy consumption by the second quarter of the 2025 financial year.

This, he adds, will result in a significant reduction in DRDGOLD’s Scope 2 emissions.

In addition, the PV facility has been tied into Eskom’s grid and the infrastructure developed to facilitate this has been handed over to Eskom, enabling DRDGOLD to wheel excess energy generated at Ergo into the national grid, which the miner says helps to offset power consumption in the rest of the business.

Overall, Pretorius says that Ergo’s near- and medium-term outlook, with its newly commissioned reclamation sites and the added benefit of 60 MW of renewable power, is positive and that the company is well-positioned to deliver on its strategy, at a capital cost of about R3.1-billion, and to be funded substantially from ongoing operations.

This will lead to another 14 years of production, notes Pretorius.

Future Proofing

While the positive gold price at the moment is welcomed, he notes that the construct of DRDGOLD’s cost profile is changing to offer better resilience should the cycle turn.

Key drivers in this regard include decreasing the complexity of operations by systematically reducing the Ergo operating footprint from 15 sites to five, lower energy costs from the solar plant and a reduction in mechanised lifting and haulage of reclaimed material.

Meanwhile, the four Ergo sites where commissioning was delayed are now in steady-state production, and this, together with the commissioning of a fifth site in June, has restored volume capacity to enable DRDGOLD to deliver in line with its guided throughput target of between 155 000 oz and 165 000 oz of gold a year, depending on volume throughput.

On the West Rand, progress at the Far West Gold Recoveries (FWGR) Phase II operations, also in Gauteng, and the establishment of the Regional Tailings Storage Facility (RTSF), continues.

Once commissioned, the RTSF will not only be large enough to receive the operation’s entire remaining resource in this region, but will also offer a complete solution to the ongoing impact of tailings storage facilities built over environmentally sensitive aquifers in the region.

The breaking of ground at this complex in June follows the appointment of a leading contractor to construct the RTSF and the receipt of the requisite permits.

At FWGR, DRDGOLD anticipates capital investment of about R7-billion over the next five years, with beneficial occupation of the RTSF targeted for the second half of the 2027 calendar year.

A monthly throughput capacity of 1.2-million tonnes at the Driefontein 2 plant is planned for the second half of the 2027 calendar year, and this could potentially add 25 years to FWGR life-of-mine.

Looking ahead, with its longer-term value creation journey in mind, Pretorius says DRDGOLD is now positioning to bring a combination of reclamation sites on stream by the 2028 financial year. These are designed to lift tonnage throughput to three-million tonnes a month, and gold production to just over 6 t/y.