050910 Electricity pylons carry power from Cape Town's Koeberg nuclear power plant July 17, 2009. South Africa will need 20 gigawatts (GW) of new power generation capacity by 2020 and would require double that amount a decade later to meet rising demand, the country's power utility said September 7, 2009. Picture taken July 17, 2009. REUTERS/Mike Hutchings (SOUTH AFRICA ENERGY BUSINESS)

The shutdown of Koeberg Unit 2 on September 7 reduced available generating capacity to 33‚159 Megawatts (MW) on September 10 compared with peak demand of 32‚647MW resulting in a margin of only 512MW or 1.5%‚ which is less than one 600MW generating unit at a modern coal-fired power station‚ Eskom said in its 70th system status bulletin.

The tiny 1.5% margin is only a tenth of the international norm of 15% and shows just how extremely tight the balance is between electricity supply and demand until the new Medupi power station‚ which has already been hit by industrial action and construction delays‚ comes online some time towards the end of next year.

Eskom said that calm had been restored at the Medupi Power Station Project site‚ following protest action by a group of workers on September 6.

The protest was contained rapidly but all workers on site were sent home as a precautionary measure‚ to ensure the safety of people and equipment.

The protest action by the workers‚ who are employed by the Medupi Power Station Civils Joint Venture (MPSJV)‚ resulted in some damage to vehicles and equipment‚ but there were no injuries.

Eskom is engaging with contractors and stakeholders to resolve the situation.

Medupi‚ the 4‚764MW power station which Eskom is building at Lephalale in Limpopo province‚ is on track to start generating power for the national grid next year. There are currently about 17‚000 workers on site at Medupi.

Unplanned outages jumped to this year’s peak of 6‚972MW on September 3 from 4‚973MW on August 30.

Planned maintenance on September 10 rose to 1‚739MW from 1‚445MW on September 6 and the lowest level this year of 845MW on July 30.

The peak planned maintenance so far this year was 7‚473MW on April 5‚ while the peak unplanned outages were 6‚972MW on September 10.

Peak evening demand is expected to ease this week from 34‚288MW on September 6 to 32‚439MW on Tuesday‚ 32‚382MW on Wednesday and 32‚297MW on Thursday as SA gradually warms up from its recent cold snap.

On August 7 Gauteng experienced its first widespread snowfalls since September 1981.

The highest actual peak demand of 35‚527MW took place on August 7.

The peak demand so far this year was supposed to be 36‚258MW on July 16 according to the 54th system status bulletin. Demand side management‚ which involves asking large industrial users to temporarily stop some industrial processes‚ meant that the actual peak demand was only 35‚443MW or a saving of 815MW on July 16.

Eskom warned that the switch from higher winter tariffs to lower summer tariffs from September 1 had seen higher demand from large industrial customers‚ so demand for electricity had not declined even though the weather had warmed up. - I-Net Bridge