State-owned electricity utility Eskom this week claimed that there had been a steady improvement in the energy availability factor (EAF) at its power stations, reporting “preliminary figures” indicating an EAF of 76.37% from the start of its financial year to May 3, 2016. The group’s financial year runs from April 1 to March 31.

In one of it regular Power Alerts, Eskom said the monthly EAF had been improving steadily since October 2015, when it was recorded at 69.87%. The utility said it had recovered to 76.25% by April.

Nevertheless, the performance remains below target, with Eskom having set a so-called ’80-10-10’ objective, requiring 80% plant availability, 10% planned maintenance and 10% unplanned maintenance over the medium term.

The utility argued that it had improved its plant performance since August last year by adhering to its ‘Tetris maintenance plan’ and a 8 500 MW maintenance budget.

“The total average for unplanned outages from April 28 to May 2, 2016, was approximately 2 819 MW, with a partial load loss average of approximately 1 249 MW. We even had partial load losses dipping to record lows of 780 MW on Tuesday, May 3, 2016,” Eskom said in a statement.

The winter plan was formally launched on April 1 and would continue until end of August.  “As a result, we have already started to ramp down planned maintenance and ramp up energy availability for the expected winter peak so that we will have sufficient capacity to meet demand whilst we still conduct the required maintenance on our power station units.”

The reduction in unplanned outages, Eskom added, had contributed to improvements of plant availability and the resultant sharp reduction in the use of the diesel-fuelled open cycle gas turbines.

Public Enterprises Minister Lynne Brown announced recently that Eskom had reduced its monthly diesel usage from R800-million to R40-million since October 2015.

She also lauded the utility for having avoided load-shedding for nearly nine months.

However, critics warn that the reduction in power cuts has been associated with a sharp fall in demand, particularly from energy-intensive sectors such as mining. Demand was estimated to have fallen to 2007/8 levels, while tariffs had risen by more than 300% over the past ten years.