Like its counterparts across the world, the South African mining industry is an electricity super user. Unsurprisingly, it was one of the first industries to comply with South Africa’s Carbon Tax Act, which is driving mining houses to alternatives to reduce OPEX while meeting its regulatory obligations.
That said, it is not only the Carbon Tax Act that is moving the industry towards change; our unreliable grid is seeing mining houses move toward more sophisticated process and control equipment which in turn requires high power quality to ensure these systems run optimally and won’t fail prematurely or frequently, causing downtime.
Additionally, mines require reliable electricity to remote locations where new operations are designed and constructed. Combined with electricity tariff hikes, one can understand why mining houses are scrambling to find feasible alternatives.
To counter grid instability, as well as availability, many mining operations are relying on internal power sources such as diesel generators to run operations. Also, mines are bringing renewable energy sources, like solar and wind, into the mix to establish a hybrid energy model of sorts.
Whilst the above does provide some form of renewable energy posture, it unfortunately still relies too heavily on fossil fuels, be it generators and grid supply, to meet daily operational demand.
The microgrid – self-containment optimised
To truly make the most of our country’s abundance of natural energy resources, in a sustainable manner, whilst reaping the benefits of reliable and quality energy, mining houses should incorporate the concept of microgrids into their operations.
Microgrids offer mines the following significant benefits:
- It harnesses modern renewable generation – wind and solar are widely available, becoming more and more cost-effective, and generally safer to operate than traditional sources.
- Energy storage – comprising battery energy storage systems (BESS) and/or thermal and mechanical methods, storage abilities support a clean energy transition by firming up the availability of intermittent power sources and increasing grid flexibility to drive positive outcomes. Moreover, battery storage is becoming increasingly affordable and attainable.
- Advanced control technologies – such as cloud computing, data analysis and IoT to optimise, autonomously schedule and control energy production and consumption.
- Microgrids allow for self-contained, on-site energy generation from greener sources that can improve a network’s sustainability, reliability, and resilience.
- Facilitating compliance and ESG.
The digital and energy partnership
Software and analytics need to be used to make the most of microgrids and ultimately a mine’s sustainability goals:
- Transparency of consumption – energy’s visibility is the starting point for decarbonisation, obtaining insights from across the corporate value chain is vital to measuring and controlling what power resources are used.
- Analytics and AI can automate the conversion of data-driven insights into real-time decision-making.
- Digital twin technologies enable modelling the characteristics of the mine (demand/load) in order to facilitate predictive shifting of flexible operations to when renewable generation is at peak
- Ecosystem collaboration that leverages the skills and know-how of end-users, technology partners, and integrators.
In order to forge a future that offers reliable, quality, and sustainable energy, mines should include on-site generation such as microgrids into their energy mix, which is realised by a partnership of energy transition and digital transformation. Ultimately, using on-site energy more efficiently, improves mining processes’ productivity, reliability, safety, and the expansion of operations.
By Vladimir Milovanovic, Vice President, Power Systems, Anglophone Africa Cluster at Schneider Electric
