Despite the current slow progress being made on the development of the site of the Medupi power station, State-owned power utility Eskom is confident that the Medupi power station, which is being built in Limpopo, will be delivered on time.

Eskom spokesperson Fani Zulu, indicates that the current progress is based on a five-day work schedule. Efforts are being put into place to accelerate the work schedule.

Eskom says that the rock foundation conditions encountered at Medupi have not been as expected.

Specifically, it has been found that although normal blasting removed the rock, it also resulted in the shattering of rock some distance away from the intended areas. It has, therefore, been necessary to resort to the use of controlled blasting through the use of more, significantly smaller, explosive charges.

Zulu reports that this did not delay the completion of the site preparation and terracing work and the site was handed over to the main civils contractors on the agreed date.

Current indications from Eskom indicate that the first unit should be ready for commercial operation in April 2012.

After the completion of the preparation of the rock excavation area, Eskom handed over the area to its subsidiary, Roshcon, for site preparation and terracing. This has been completed and the rock excavation area has been handed over to the MPS joint venture between civils contractors Murray & Roberts, Concor and Grinaker-LTA.

The turbine generator contractor for the Medupi project, Alstom South Africa, is on site and is supervising the construction of the turbine hall in line with its overall design for the project.

Eskom reports that Hitachi Power Africa, boiler contractor for the Medupi project, is on site and is in the process of completing the construction of the company’s on-site fabrication plant.

The design reviews of the boilers and turbines are ongoing.

The interfaces between the main civils, turbine and boiler contracts are being clarified, with each of the contractors’ individual programmes being integrated into the overall Medupi schedule.

Environmental Concerns
During the preparation of the Medupi site, Eskom reports that the utility took a number of environmental issues into consideration.

In June, Engineering News reported that the foremost environ- mental consideration was the relocation of a baobab tree that was believed to be a few hundred years old and which has been described as a visual beacon.

After a lengthy process, the tree was relocated to where the future entrance to the power station will be sited. The 70-t tree sprouted its first leaves in February.

Many other indigenous trees were also either replanted or transported to a special nursery at the nearby Matimba power station.

Because the site for the Medupi power station was previously an area where a number of wild animals roamed freely, Eskom needed to relocate some 30 to 40 animals to a neighbouring nature reserve.

The utility reports that a programme has been initiated to capture and relocate all the snakes found on the construction site; this is being done in conjunction with a local snake expert. The snake expert also presents educational talks to the workers on site.

The topsoil and vegetation, which are being removed as part of the clearing process, are being preserved to be used for the rehabilitation of the existing Matimba power station ash dump, and possibly some of the Exxaro and Grootegeluk mine spoil dumps.

Coal Supply Contract
An agreement on the coal supply contract with Medupi has been reached between Eskom and coal-mining giant Exxaro.

In terms of the agreement, Exxaro’s Grootegeluk mine, will, over the next 40 years, supply an average of 14,6-million tons of power-station-grade coal to Medupi every year. The coal to Medupi will be supplied through a brownfield expansion of the Grootegeluk mine with mining from the existing opencast pit continuing at an accelerated rate.

The coal beneficiation process will be handled by two new dense-media facilities, namely the Grootegeluk 7 and the Grootegeluk 8 beneficiation plants, which will be constructed at the mine.
Exxaro has a similar coal supply agreement with Eskom for the Matimba power station.

Social Development
A significant challenge that Eskom is faced with on a continuous basis is the skills crisis. Eskom is resolving this crisis through ongoing recruitment exhibition events, sourcing skills locally and internationally, and entering into partnership with local and international project management companies.

Eskom reports that the require- ment of skills development and localisation of people and resources is receiving significant focus from the utility, as well as from contractors. Further, plans are in place for contractors to provide training for the local people and the main civils contractor has established a training centre near the site.

In June, it was reported that the utility had about 850 contractor employees working on the project.

However, this number was set to increase over the duration of the roll-out of the civils work.

This expansion has neces- sitated detailed planning and rigorous health, safety and environmental practices in an effort to instil a safe-practice philosophy in all its workers.

The Medupi power station is the first power station that is being constructed as part of Eskom’s capacity expansion programme, which aims to increase the utility’s service offering to the public. It is the first baseload, coal-fired station to be built in South Africa in over 20 years and its delivery is viewed as critical, given that Eskom is currently operating at an uncomfortably low reserve margin of well below 10%.

Once Medupi reaches full capacity in 2016, its 4 800-MW generation capacity will provide the utility with a capacity increase which will be in excess of 10%.

The baseload plant will be made up of six 800-MW units and will be commissioned in phases.

The first unit of the Medupi power station could be operational by mid-2012. The remaining units are scheduled to be commissioned at nine-monthly intervals, so the last units are expected to be commissioned by March 2016.

To subscribe to Engineering News's print magazine email subscriptions@creamermedia.co.za or buy now.