The three-phase renewable energy rollout of Harmony Gold is not only driving decarbonisation but the reduction in electricity costs has the potential also to extend the mine life through a triple-win outcome.

On the productivity front, strides are being made under the S300 business improvement platform, which involves each of the company’s conventional underground crews safely producing 300 m2 of material per crew per month. (Also watch attached Creamer Media video.)

Through the first two phases alone, the JSE-listed company is estimating savings of R425-million a year and reducing carbon emissions by 60%, with the third phase involving the study of technologies that have the potential to provide baseload, Harmony CEO Peter Steenkamp outlined to Mining Weekly in an online interview.

With its expected copper projects further reducing its carbon footprint, the gold-mining company is targeting a net-zero carbon outcome by 2045.

When S300 began, crews were doing in the region of 240 m2/crew/month as a mean across the conventional underground operations and the run rate is now up to 260 to 270 m2/crew/month.

“We’ve got that last little bit to go, and if you translate that into miners’ language it’s that extra one-and-a-half blocks that we’re looking for,” said Harmony Group COO Beyers Nel.

S300, he explained, involves technology and people aspects that relate to a productive environment and resource energy around improving the environment for people to be successful, whether that be through the use of localised hydropower to improve drilling cycles for conventional rockdrill operators, or different operating shift environments.

“There’s a spread of many little projects that we’re trying to drive to facilitate the growth to S300,” he added.

These questions were put to Steenkamp.

Mining Weekly: You are close to self-generating some of your electricity requirements and the projected savings are already looking attractive.

Steenkamp: Phase 1 is the 30 MW through a power purchase arrangement (PPA) in the Welkom area, close to our Tshepong gold mine. Then Phase 2 is 137-MW plant that we're going to build in two legs. The first 100 MW is being built by ourselves with the green loan that we secured some time ago, and another 37 MW, which will also be through a PPA programme. In Phase 3, we are looking at technologies that can potentially give us some baseload and that work is still in the prefeasibility phase in terms of what can potentially give us that kind of extra boost. We're quite excited about the 30 MW and under the 137 MW that we're going to put together, and because of that it's now fully approved in terms of our approvals and the 30 MW is currently in construction. By September next year, all of that will be built, and 30 MW by the end of this financial year, which is in June.

Can lower-priced self-generated electricity play a role in extending mine life?

That’s what we always do when we cut costs. We'd be plugging in a cost figure, we plug in what will determine our cutoffs. This will probably bring the cost down by about R10 000 a kilogram. If you plug it in, that will not move the needle that much, but the more you have renewables and cheaper electricity in place, then it can have the effect of being able to beat inflation and when you plug in the price and you plug in the cost, then we get a mine life that could potentially bring some resources to the reserves.

Productivity is so important in mining and S300 seems to be working well.

Yes, the best possible way to bring profit to the bottom line is to improve productivity. We've got quite a significant leadership under our Group chief operating officer Beyers Nel and lots of projects to improve our productivity over time. The S for safety is very intentional. Safety is always first and then it’s about the productivity improvements. We will not make any productivity improvements at the cost of safety. It must all be safe, and we've moved the needle under S300. If we look at...