Duvha power station
“’ where a 600MW generating
unit failed last year
Johannesburg, South Africa — ESI-AFRICA.COM — 30 January 2012 – At one point in January, peak demand of 30,282MW in South Africa was met by available capacity of 30,742MW “’ a margin of only 1.5% or 460MW (which is less than one generating unit at a modern coal generating plant) The internationally accepted safe margin is 15%.

In its latest capacity update service released here, South African national power utility Eskom Holdings said the reason for this low margin was that it carried out planned maintenance on its power stations during the seasonally low demand summer months, so that the power stations were ready to handle the peak winter demand months of June and July, when service delivery protests also peaked.

Eskom added that the electricity generating capacity available to meet peak demand on 26 January was 33,189 MW, while demand was expected to be 31,106 MW “’ a margin of only 83MW.

It pointed out that last year in February, a 600MW generating unit at Duvha failed during tests as it was being returned to service, while in January 2003 a similar event took place.

The statement went on to emphasise that this year and next year Eskom did not have the spare capacity to have a large generating unit fail, as the first unit of the new Medupi power station will only come on line in 2013.