The cost of Grootvlei’s mothballs

ALARGELY ceremonial visit recently to the Grootvlei Power Station by President Jacob Zuma led many to wonder why it had taken so long to recommission the station after the energy crisis struck in early 2008.

What made this surprising to some electrical and mechanical engineers was that when Grootvlei was mothballed it still had a substantial part of its useful life left. Grootvlei was the youngest, and apparently the biggest, of the mothballed plants.

It has been put to me by civil engineer Chris Herold that the reason older stations were mothballed was to make the fullest use of the biggest and most efficient new stations. Then, so as to delay capital expenditure on the first of the new- generation stations, the mothballed stations would be recomissioned.

Given that this is eminently sound planning, surely the mothballing should have been very carefully planned and executed, and wouldn’t sound procedures have been put in place to bring the plants on-stream again? In what is a partial response, Eskom senior general manager Andrew Etzinger tells me substantial changes to the plant were necessary because it had been mothballed for so long.

The first of these was the design and implementation of new computerised control systems.

When Grootvlei was built, computers vital in the operation of modern power plants for control and condition monitoring weren’t readily available. In effect, it became a matter of retro-fitting, never easy.

The second problem was ensuring the reopened Grootvlei complied with significantly tighter environmental legislation.

This meant putting in place more stringent measures.

The third was to reconfigure the coal-handling system. Etzinger says coal-handling technology is now significantly advanced, and this part of the plant had to be reconstructed.

Grootvlei re-entered service about two years ago, which suggests the recommissioning process took about three years to design and complete. This can be regarded either as a remarkable achievement, or an example of plainly deficient management.