Eskom developing bitcoin mining plan but needs Nersa’s nod

Eskom is working with energy regulator Nersa on a framework that will allow it to sell surplus daytime electricity to bitcoin miners but said the regulator will still need to run a public consultation before any pilot can begin.

Agnes Mlambo, Eskom’s head of distribution, said the utility had been engaging with bitcoin mining operators because their operations can ramp up and down at short notice in response to whether surplus energy is available on the grid.

“We do have bitcoin miners that we have been talking to, and the good thing with the miners is that their operations allow them to ramp up as and when energy is available, and also to ramp down as and when that excess energy is not available,” Mlambo said.

Eskom wanted to run a pilot, she said, but the process was taking longer than initially planned because of the regulatory steps that still needed to be worked through.

“There are some rules that we need to follow with Nersa, but we are in a process of developing the framework, and with that framework, Nersa will also have to do a public consultation process.”

Mlambo said the surplus-power offer was not exclusive to bitcoin miners. Existing industrial customers had been given the opportunity to use the excess daytime capacity first, but the nature of manufacturing operations meant most could not flex quickly enough to make use of it.

“In a manufacturing environment, it is not that easy to ramp up and down your production, and that is why our customers have not been able to capitalise on that offer in terms of utilising that excess energy,” she said.

Excess power

South Africa’s daytime electricity demand profile has been reshaped by the rapid adoption of rooftop solar, which now displaces significant grid demand during daylight hours. The pattern leaves Eskom with surplus capacity in the middle of the day that it has struggled to monetise.

Eskom chairman Mteto Nyati set out the broader thinking at a BizNews conference in March, saying the utility was evaluating ways to sell the midday surplus at discounted rates to flexible, high-demand users such as bitcoin miners. Nyati said demand typically spiked in the early morning as households prepared for work and businesses opened, then dropped sharply as solar generation ramped up.

Read: Eskom to decide fate of older coal stations by September

The most detailed public account of the commercial model so far appeared in Daily Maverick in January, when Bitmach co-founder Stafford Masie described a demand-response proposition capable of absorbing up to 5GW instantaneously and being switched off just as quickly. Masie contrasted the flexibility of bitcoin mining rigs with industrial loads such as ferrochrome smelters, which he said typically need between four hours and four days of notice to shut down.

Bitmach was co-founded by Carel de Jager — a former asset care engineer at Eskom’s Lethabo power station — with businessman Rob Hersov and technology entrepreneur Stafford Masie. De Jager first published the thesis that Eskom should monetise surplus electricity by mining bitcoin in 2018. The company is not necessarily the only potential miner in the mix; Mlambo’s reference to bitcoin miners in the plural suggests Eskom may be engaging more than one operator.

Any tariff or commercial structure specific to a new class of customer will require Nersa approval, and the public consultation requirement means a pilot is unlikely to launch in the near term.  — (c) 2026 NewsCentral Media