What is happening at the Koeberg Power Station

On Sunday, February 1, Unit One at the Koeberg Power Station tripped due to an earth fault.

The earth fault was triggered by scaffolding touching the neutral earthing bar above the restricted earth circuit.

Eskom’s problems continue to escalate on Thursday, February 5, while the unit was being synchronised to the national grid, a breaker trip occurred resulting in a turbine trip.

This meant that the country’s power grid went into the weekend without the 930MW that was expected to come on line from this unit.

The system will continue to be under severe pressure over the next week, so the risk of load shedding remains high, especially today (Monday).

There is a shortage of generation capacity due to units that are on planned and unplanned maintenance.

The focus is on returning the units that are on unplanned maintenance back on line in order to increase available capacity next week.

Eskom will also use the weekend to build up diesel stocks and dam water levels for the open cycle gas turbines (OCGTs) and pumped storage schemes respectively in order to ensure that these reserves are available during the week.

Eskom has decided to keep the Koeberg’s Unit One on shutdown to enable completion of a detailed investigation to determine the root cause of the trip.

The reactor is being operated as per the safety specifications and there is no threat to plant, personnel, members of the public, and the environment.

At no stage during the incidents, was there any threat to the reactor or nuclear safety.

Koeberg Unit One is scheduled to enter into a refueling and maintenance outage today and is expected to return back to service at the end of May.

The scheduled shutdown of Koeberg Unit One is part of Eskom’s overall maintenance programme for its fleet of power stations.

Every 16 to 18 months, each of the two units at Koeberg is shut down for refuelling, inspection and maintenance.

The routine shutdowns are scheduled so as to avoid having both units out of service at the same time and to avoid the winter months in each year.

During these routine planned outages, one third of the used nuclear fuel is replaced with new fuel.

Statutory inspections and maintenance is performed, and modifications, that will ensure that international safety standards continue to be met or that improve the plant performance, are implemented.

Koeberg Unit Two is currently operating at 100 per cent power and is contributing 930MW to the national grid.

Eskom reminded the community that load shedding is implemented as a last resort to protect the grid, shedding only what is required to balance demand and supply.

Load shedding updates and schedules are available at https://loadshedding.eskom.co.za.