Eskom to increase OCGT use at certain power stations

7th December 2018

Although the risk of rotational load-shedding during the festive season is high, State-owned power utility Eskom will resort to increasingly using open-cycle gas turbines (OCGTs) at certain power stations to minimise the risk of load-shedding.

This follows the statement Eskom made about ten of its power stations having less than the required minimum amount of 20 days of stockpile, with five of them having less than ten days of coal stock left. Measures are, however, in place to boost the coal stockpile at the respective ten stations that fell below the grid code requirement. 

Throughout the year, Eskom ran OCGTs to manage the system during the unplanned industrial action and for system support in October. As a result, Eskom produced 193 GWh/y at the cost of R538-million. 

A budget of between R750-million and R1-billion for diesel has been allocated to fund the unexpected increase in using OCGTs till the end of March 2019. This does not include the cost of using OCGTs to mitigate the risk of rain.

At a State of the System event, held in Johannesburg last month, Eskom acting group executive transmission Willy Majola explained the difference between blackouts and load-shedding. “A blackout refers to the complete loss of all generation in the country where no power station is generating electricity, whereas with load-shedding, you only shut down one portion of a power station and then one comes back on line, and then another.” 

Majola pointed out that, although there would not be any blackouts this festive season, rotational load-shedding was likely to be implemented.

Stage 1 of rotational load-shedding was implemented last month. Eskom has advised customers to continuously check load-shedding schedules on its website and plan on the assumption that load-shedding will take place.