Power utility Eskom should link its delayed Tubatse pumped storage scheme to the need for Hillside Aluminium to go green.
This could be done, a close observer of the intensive electricity user sector of the South African economy contends, through Eskom doing an independent power producer (IPP) or public-private partnership transaction with Hillside aluminium, a critically important commercial partner to Eskom and its closest operational customer.
As reported by Mining Weekly last week, if the ASX- LSE- and JSE-listed South32 group is unable to secure an affordable source of low-carbon electricity for Hillside, this key KwaZulu-Natal smelter risks becoming uncompetitive in the international market over time, given the emergence of carbon border tariffs and end-user demand for green aluminium.
The contention being put forward is that Eskom’s De Hoop dam Tubatse hydro-battery project, which was held back several years ago owing to capital constraints, could be able to do what chemical batteries cannot, and assist the South African economy materially at the same time.
Had the Tubatse hydro-battery project gone ahead when originally scheduled, it would likely have paid for itself by now in diesel saving during day peaks.
Now, owing to the large capacity of the Tubatse hydro-battery requiring an equally large customer, Hillside and Eskom are seen as a perfect match for a deal of this nature.
South32’s initial study results indicate that, combined with battery storage, renewables could be technically feasible, through new solar photovoltaic and wind capacity.
Owing to the electricity-intensive aluminium smelter’s significant economic and social importance, South32 has commenced just transition planning to support options for the smelter if its energy transition is not commercially viable and the smelter becomes uncompetitive.
The aluminium smelter plays an important role in underpinning the stability of the national electricity grid, as Eskom has the flexibility to interrupt supply to the smelter to support management of the grid and minimise load-shedding.
But Hillside also accounts for a high 58% of the Scope 1 and 2 carbon emissions of the four operations that South32 runs owing to its carbon-intensive electricity consumption and is in need of significant greening.
Many large long-life hydro-batteries are going ahead around the world because of their ability to store electrical energy in large quantities.
It is contended that Tubatse would enable a green Hillside smelter to compete from 2030 to beyond 2050 only if Eskom and Hillside continue their very close relationship over these three necessary phases:
Eskom IPP contracts the construction of the 12 000 MWh Tubatse hydro-battery to Hillside through a contractual amendment of their power supply contract on the basis of the integrated Eskom grid being able to optimise the use of the 12 000 MWh Hillside hydro-battery to eliminate burning turbine diesel during daily peak load periods, and both Eskom, and a greener Hillside scoring the carbon-credits and avoiding expensive peak tariffs;
New 1 000 MW photovoltaic and wind electricity being wheeled over Eskom grid to power Hillside during most days, with Eskom grid backup; and
Another new 1 000 MW photovoltaic and wind to recharge the Tubatse hydro-battery, again with Eskom grid backup.
Currently Eskom grid is the backup to South32’s Mozal Aluminium smelter in Mozambique, which is hydropowered.
Without the 12 000 MWh IPP hydro-battery project available from Eskom, there is a likelihood that Hillside will close when its low-cost Eskom power contract expires in less than ten years.
Could Hillside's modern potlines then be relocated to the Democratic Republic of Congo (DRC), for 24-hour green power from the Inga 3 hydropower project?
Was it BHP Billiton, out of which South32 was unbundled, that replaced President Thabo Mbeki's important Westcor Project, by convincing the DRC that aluminium smelting in the DRC is better than 4 000 MW to...