150711. Sunset in Crownmines, Johannesburg. The picture can be used for Eskom energy supply crisis. Picture: Dumisani Sibeko

Johannesburg - Eskom has started commissioning a number of critical systems at Medupi Unit 6, which is scheduled for synchronisation to the grid during the second half of the year.

The parts that are running include the fuel receiving system, some control systems, the system to transfer fuel to boilers and fans for dry-cooling the station.

“The civil [works] at Medupi are nearly completed. The coal plant is done. Most of the systems are actually being commissioned,” chief executive Brian Dames told the media during the company’s quarterly briefing on the state of the electricity system yesterday.

The fixing of defective boilers and welding by Hitachi Power Africa was on track and Siemens, which is working alongside Alstom, had made “substantial progress” on putting the boiler protection system in place.

But the road is going to get tougher before the country gets much-needed relief from power shortages.

“During the months of April to July, the electricity system is going to be extremely tight, particularly [during] the winter peaks,” Public Enterprises Minister Malusi Gigaba said during the briefing.

The absence of a number of short-term supply contracts, which Eskom relied on when it found itself in a tight position in the past, was one of the factors that led it to declare two supply emergencies last week.

This summer Eskom has declared three emergencies, a protocol it has not had to adopt since 2008.

The short-term contracts were not renewed in December.

What made matters worse last week was a halving of the supply that Eskom imports from Mozambique’s Cahora Bassa hydroelectric plant. Eskom imports 1 500 megawatts from Cahora Bassa and a further 107MW from a gas-fired station, also in Mozambique. Cahora Bassa supply has since been restored to full capacity.

Dames indicated the Mozambican imports formed an important part of Eskom’s power supply and the utility was looking at more hydroelectric projects in the Southern African Development Community.

However, Eskom’s electricity exports to the region have unnerved some South Africans, who feel it should put the country’s needs first.

Dames said that while Eskom sold power to utilities in the region, it did not do so when its system was tight. Power exported to regional utilities ranged between 100MW and “a few hundred” megawatts.

“It’s a small portion,” he said. If, for instance, 1 000MW was exported, 900MW of that went to smelters, which were Eskom customers. “Most of our electricity exports go to our customers, not utilities.”

As for the short-term contracts to increase Eskom’s supply capacity, government departments were in discussions about finding funding to extend them. They included supply from municipalities and independent power producers.

The government was also considering converting some of Eskom’s power stations to run on gas. Eskom had issued a request for proposals to determine how much gas was available and to see if it could supply its open gas cycle turbines on a long-term basis.

“The open gas cycle turbines have 2 000MW capacity. We can run [them] with gas as well and we’d most probably get close to 3 000MW output if we do,” Dames said. - Business Report