According to TechCentral, Eskom has put forward a two-year pilot tariff that would allow cryptocurrency miners to buy surplus electricity at a benchmark price of roughly R1.20 per kilowatt-hour. The proposal is being examined by the energy regulator Nersa, which is seeking comments until 23 October and will hold public hearings on 3 November.
A pilot tariff is a temporary price plan used to test a new rate before it becomes permanent. The discount that miners might receive compared with standard rates has not been disclosed, and the economic case will depend on how large that discount is and whether miners can be switched off when the grid is under stress.
The pilot is open to “flexible-load” customers, users who can adjust their power consumption in response to grid needs. It applies only to customers in the highest-voltage category in the southern transmission zone; lower-voltage users are excluded. Participants may be required to join demand-response programmes, which could involve automatic telemetry, minimum curtailment requirements and penalties for non-performance.
Eskom estimates that surplus capacity could range from about 5 GW to 7 GW at times, driven by daytime solar generation and low demand at night. In 2028 the utility expects more than 5 TWh of power could be curtailed if no alternative use is found. Curtailment is costly because power purchase agreements compensate producers for energy they were ready to deliver.
Two cryptocurrency mining firms have expressed interest, with an initial combined demand of roughly 10 MW and the possibility of expanding to as much as 500 MW. The proposal mirrors a model used in Texas, where Riot Platforms earned US$21 million in power credits in the first quarter of 2026 by selling excess power back to the grid and participating in demand-response programmes, bringing its effective power cost to about 3 US cents per kilowatt-hour.
Critics note that the R1.20/kWh benchmark may still be too high for miners who aim for sub-$0.05 per kilowatt-hour (about 82 cents at the current exchange rate). The success of the pilot will hinge on the final discount, the technical rules for rapid load shedding, and whether other flexible-load users can compete for the same tariff.
For more on the regulatory process, see Nersa’s consultation paper at Nersa. The broader implications for South Africa’s power surplus and the emerging crypto-mining sector will become clearer once the regulator publishes its decision on 7 December.
Steven Boykey Sidley, a partner at Bridge Capital, highlighted that the discount size will be decisive, noting that “the devil lies in the details” when assessing whether the tariff truly benefits Eskom and miners alike. He questioned whether other “time-flexible” off-takers might compete for the same rates, and whether miners would need to rely on auto-telemetry for rapid shut-downs. Sidley, who also teaches at the University of Johannesburg, stressed that a well-designed demand-response framework could turn surplus electricity into a revenue stream, but only if the economic justification holds up under scrutiny.
Christo de Wit, South Africa country manager at Luno, described the proposal as “innovative and forward-looking”, arguing that it channels otherwise wasted power into productive activity. He pointed out that the pilot’s focus on the highest-voltage customers in the southern transmission zone aligns with Eskom’s existing Megaflex structure, where most weekday daytime periods would shift to off-peak status. De Wit suggested that extending the model to other qualifying flexible customers could broaden the impact, provided the technical and operational thresholds are clearly defined.
The consultation paper notes that customers supplied below 500 V are excluded and that rates in other zones would be escalated in line with Megaflex, leaving the full schedule of demand, capacity and network charges unpublished. This lack of transparency means participants cannot yet calculate the total cost of participation, a gap that Nersa hopes to fill through the public hearings on 3 November. The regulator’s decision, slated for 7 December, will determine whether the tariff remains a benchmark price or incorporates additional charges based on actual usage patterns.
Agnes Mlambo, who acted as Eskom’s head of distribution in April, warned that manufacturers have struggled to adjust production in response to surplus power, pointing to the challenge of translating flexible-load concepts into practice. She emphasized that ramp-up and ramp-down capabilities differ across industries, and that any mandatory demand-response obligations must consider the practical limits of equipment and operational schedules. This perspective feeds into Nersa’s request for input on mandatory telemetry, metering and penalty structures for pilot participants.
We reported in September when Nersa’s own committee members first questioned the idea, warning of price discrimination and competition concerns. Eskom has since turned that internal discussion into a formal consultation with an actual benchmark price attached, which is the detail that was missing a month ago.
