ELECTRICITY supply will be highly constrained for at least the next five years, due to drastic deterioration in the state of Eskom’s power stations brought about by lack of maintenance.

While attention has been on a date for the first unit of Medupi to start operating — now set for June next year — as being key to alleviating the pressure, the reality is its 800MW will make little difference to supply constraints, a presentation prepared by Eskom management shows.

The presentation says that since March 2010, when SA adopted a policy of "keep the lights on" Eskom’s energy availability factor (EAF) — the percentage of the fleet available after breakdowns and planned maintenance — has dropped from 85% to 75%.

This is equal to a loss of 4,200MW in five years — almost as large as the 4,800MW that will eventually be generated by the entire Medupi station.

Best international practice is to achieve 90% plant availability, with 10% down at any given moment, through planned and unplanned outages. This ratio has dropped in SA over the years, reaching 85% in 2010 and plummeting to 75% this year.

While Public Enterprises Minister Lynne Brown has tried to reassure the public with promises that Medupi’s first unit — unit 6 — will generate power by next June, a far more important priority is restoring Eskom’s existing fleet to health. Energy analyst Chris Yelland said Eskom’s "real problem" was that the energy availability factor had dropped dramatically.

"Even though Eskom has brought in more capacity, by returning mothballed stations to service, the total availability of their plant is less than when they started doing that," he said.

Eskom was now paying the price of its "keeping the lights on at all costs" policy, he said.

Acting CE of Business Unity SA Cas Coovadia said business was extremely concerned about the short-to medium-term power crisis and was compiling a strategy document on how to proceed. "We have held two workshops, including with Eskom, and are putting together a document, after which we hope to meet the ministers involved. We want to release the capacity of the different parts of industry to deal with the power situation," he said on Sunday.

Eskom said on Friday it had a plan to restore plant availability over five years, reaching 85% by 2018, but falling short of the 90% benchmark. Electricity supply would remain severely constrained until then, it said. "As most … power stations are older than 30 years, and are being run very hard, they will be prone to unplanned outages. It is thus likely that while generating capacity includes a significant number of older power stations, the system EAF is unlikely to improve above 85%," Eskom said.

Achieving these targets will not be easy. The company is in a vicious cycle, the presentation points out, as due to plant breakdowns it lacks space to do maintenance. To complete the maintenance it should undertake in 2015 would require that 7,400MW be added to the grid.

Mr Yelland said apart from problems with its plant, Eskom also has a skills problem and often fails to bring plants back up on time after maintenance, further lowering plant availability.

Among strategies in the plan to reach sustainability are redeploying technical staff from head office to power stations and giving managers of power stations a greater say in determining the time for maintenance.

"Managers … have been told to do the right thing rather than to keep the lights on. The strategy seems to have changed and Eskom appears to be saying that if that leads to load shedding, so be it," said Mr Yelland.

As well as sharing its position with politicians and the government, Eskom said two weeks ago it had revised its load-shedding schedules to prepare for a planned reduction in load.

The company said on Friday Medupi unit 6 would come on stream next June, followed by unit 5 in August and Kusile unit 1 in December. But there is widespread speculation that Medupi unit 5 will not meet its deadline, as resources had been diverted to meet the deadline for unit 6. The deadline for unit 6 has shifted several times from the initial plan to produce power by late 2012.