{"id":645013,"date":"2022-11-22T08:36:50","date_gmt":"2022-11-22T06:36:50","guid":{"rendered":"https:\/\/businesstech.co.za\/news\/?p=645013"},"modified":"2022-11-22T08:36:50","modified_gmt":"2022-11-22T06:36:50","slug":"south-africa-at-risk-of-a-total-blackout-expert","status":"publish","type":"post","link":"https:\/\/businesstech.co.za\/news\/energy\/645013\/south-africa-at-risk-of-a-total-blackout-expert\/","title":{"rendered":"South Africa at risk of a total blackout: expert"},"content":{"rendered":"

Energy expert Professor Anton Eberhard has warned that Eskom\u2019s decision not to refuel its diesel open cycle gas turbines (OCGTs) increases the risk of a system failure.<\/p>\n

Eberhard is the director of Power Futures Lab at the University of Cape Town\u2019s Graduate School of Business.<\/p>\n

Over the weekend, Eskom confirmed that diesel tanks at its OCGTs run have physically run out and are empty.<\/p>\n

The power utility added that the tanks will not be replenished until 1 April 2023 as its spending overrun on diesel to date is twice the budget for the current financial year.<\/p>\n

Eskom,\u00a0responding to questions from Chris Yelland<\/a><\/strong>, said it has not ordered additional diesel and has no outstanding orders.<\/p>\n

What it means, in simple terms, is that the Eskom OCGTs will be unavailable until at least 1 April 2023.<\/p>\n

Eskom\u2019s new OCGT power stations are intended to be used during peak periods and emergency situations to supply electricity to the national grid.<\/p>\n

Without operational OCGTs, Eskom cannot respond to emergencies, increasing the risk of a system collapse.<\/p>\n

Eberhard said<\/a><\/strong>\u00a0Eskom\u2019s decision not to refuel its diesel OCGTs removes 2,067MW from rapid response resources available to the system operator.<\/p>\n

\u201cAt a time of intermittent and declining coal plant output, it increases the risk of more load-shedding and system failure,\u201d he said.<\/p>\n

He added that the cost of unserved energy for South Africa\u2019s economy is much higher than the cost of running the Ankerlig (1,327MW) and Gourikwa (740MW) OCGT diesel plants.<\/p>\n

\u201cIt is mad economics for Eskom to stop fuelling these due to regulatory constraints. The ministers are asleep again,\u201d he said.<\/p>\n

\u201cThe president will need to intervene. It is not a good idea to go into the ANC December conference with these power sector risks and levels of load-shedding that anger people.\u201d<\/p>\n

System failure and a total blackout<\/strong><\/p>\n

System failure and a total blackout occur when the frequency of South Africa\u2019s alternating current supply gets too high or too low.<\/p>\n

The system operates at 50 hertz (Hz). When this frequency goes too high or too low, you have a significant risk to the system.<\/p>\n

Safety features designed to protect the equipment against catastrophic failure will cause a cascading trip-out if the grid becomes overloaded.<\/p>\n

When demand exceeds supply, you have an overloading of generators, transformers, cables, and switch gear.<\/p>\n

Trips are installed to prevent massive damage in the event equipment is overloaded.<\/p>\n

If there is an overload and equipment starts to trip, the overall electricity supply decreases, but the demand stays the same.<\/p>\n

It places even greater strain on the parts of the grid that are still on, causing them to overload and trip if you do not act quickly.<\/p>\n

If you had an aerial view of the country, you would see these cascading trip-outs spread as a wave of darkness sweeping the country.<\/p>\n

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Besides leaving the country without power, a national blackout would put Eskom in a position where it needed to bring power back online from scratch \u2013 a \u201cblack start\u201d.<\/p>\n

This process can take between two and three weeks, which will cause havoc across South Africa.<\/p>\n

Power plants use some electricity they generate to run equipment like conveyor belts that feed coal into furnaces.<\/p>\n

To start these up, you must begin with a small diesel generator to bootstrap the rest of the power plant.<\/p>\n

The small generator generally starts up a larger generator, which fires up the rest of the plant.<\/p>\n

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