With the stabilisation of South Africa’s energy crisis still years away, investment will be critical to ensure the country’s heavily energy-dependent mines remain operational and viable.

While that investment can be, in some cases, significant, the productivity gains can be massive.

South Africa’s mines could see great benefit in pursuing a mix of hybrid energy sources, generating excess energy, reducing consumption and enhancing their approach to efficiencies, says Brazilian motor and controls manufacturer WEG South African subsidiary Zest WEG group CEO Juliano Vargas.

“Energy availability and stability remains one of the most impactful restraints for economic development. This scenario [of power and infrastructure failures] is not going to change in the short term,” he continues, noting that there is much investment to be made.

“If we do not start doing those investments now, economic growth is not going to happen.”

As financial and natural resources are limited, how efficiently energy is generated and used plays an important role on the energy scenario and has to be taken in consideration when planning for current and future needs.

In particular, the mining sector needs to consider the balance between supply and consumption, with a focus on efficiency and sustainability.

“We have to weigh the risk versus the opportunity. We have to understand the long-term situation.”

A typical midsized mine uses 15 MW to 20 MW of energy, and its own production of energy for operational use, as well as potentially selling any excess back to the national grid, can ease further investment pressures and energy constraints.

“It is time to place pressure on government to allow excess energy to be sold to the national grid,” Vargas says.

If every mine produces 10% excess energy for resale, it could open up gigawatts within State-owned power utility Eskom’s system.

This would enable Eskom to undertake maintenance and project developments to stabilise the current installed capacity and increase it gradually, as well as act as a buffer when mechanical faults occur in the generation.

In addition, the benefits can extend to nearby mining communities, with excess energy available for residential purposes, further easing strain on the utility.

With various self-generation energy solutions to consider, from solar, wind and gas through to hydropower and batteries, a holistic approach is needed to leverage technologies that offer improved operational efficiency with better return on investment – and most of these technologies are readily available.

“There is so much potential and we should explore these opportunities,” he says.

The incorporation of renewable-energy-generation solutions in the energy mix has already proven to be beneficial by assisting in the reduction the impact associated with load-shedding in South Africa.

“We have to play with these solutions. We cannot just stick to one or the other -- we have the advantage of rapid technological improvements, which now allow us to develop hybrid energy solutions.

“In many instances, it is possible to leverage and extrapolate available technologies to offer improved operational energy efficiency, which will provide significant savings and a shortened return on investment,” Vargas continues.

He further notes that many people do not realise that Industry 4.0 is already here, from software to sensors, and this will be key in minimising investment for generation, as energy is used better.

It is necessary to weigh the need for energy generation against the amount consumed and work to create efficiencies, which can be gained through the use of software and technologies, such as the WEG Motor Scan Gateway products already offered by Zest WEG.

He also points to the use of premium high-efficiency (IE3) motors instead of standard efficiency, or IE1, units, effectively creating energy savings of more than 30%.

While motor the could be 20% more expensive, it will ultimately save 25% or more of an energy bill, as electricity accounts for 90% of the running cost.

“If you run that on a 24-hour basis, seven days a week, in normal applications in an industry, your payback can be within six months, generating savings that can be elsewhere used while also reducing the burden on the system.

“Yes, an initial investment will be necessary, but the payback period will be quick, owing to the energy savings,” he concludes.