State-owned power utility Eskom reports that significant progress is being made with the construction work currently under way at the Medupi power station, in Limpopo, which is a major project for South Africa’s energy sector.

“There is physical progress since construction work started in May 2007. Currently, all major contracts have been placed except for a few, which the project does not need yet,” says Eskom project manager for the Medupi power station Roman Crookes.

The utility reports that the steel boiler superstructure has been erected for unit six, the first unit, and the installation of the boiler heat exchange surfaces is now in hand. Further, construction has also started on the unit five boiler and on the turbine generator for unit six. With the new timelines, the first unit will be commissioned towards the end of 2012 and the project is progressing to meet the deadline, he says.

Construction of the outer shells of both of the station’s chimneys is complete. The construction of the auxiliary bay is also under way, as well as that of the water supply system, the water treatment plant, the coal stockyard and the conveying system for transporting the coal to the site.

An overland conveyor will transport coal over a distance of 5 km from diversified miner Exxaro’s Grootegeluk mine, which is being expanded to supply 14,6-million tons of coal a year to the Medupi power station.

“Coal quality plays a significant role in a power station. One of the first steps in building a power station is to test the coal to enable the boiler contractor to design and build boilers that can efficiently control the combustion of that particular type and quality of coal.

“The coal has to be tested for its calorific value or energy content, ash content, abrasiveness, sulphur content and volatile constituents. The Medupi boilers are specifically designed for the coal mined at Grootegeluk,” Crookes explains.

Meanwhile, there are about 8 000 employees working on this project and numbers are expected to reach about 9 000 during peak construction.

Challenges

Crookes says that there will always be challenges with any project, particularly with one of the magnitude of the Medupi project. One of the first such challenges for Medupi was unexpected widespread fracturing of the bedrock during blasting for foundation excavations. This necessitated additional site preparation with the ground level being lowered by several metres to achieve the required founding conditions, he explains.

“One of the current challenges is obtaining the necessary statutory approvals for the high-voltage power lines and new sub- stations required, connecting Medupi to Eskom’s grid system. Most of these acquisitions and approvals have now been completed but those required for Medupi’s last two units, including two new 400-kV substations, are still in progress.”

Town Development

Eskom has built 900 houses, valued at R1-billion, for its employees to date, explains Crookes.

“Eskom is assisting in supplying five clinics in the neighbouring areas with new equipment and is looking into assisting with refurbishing certain schools. Eskom is also in the process of recruiting more teachers to enhance the quality of teaching in Lephalale. Our main focus is mathe- matics, science and HIV/Aids education,” he adds.

The project also aims to develop the economy of Lephalale by creating employment opportunities for individuals in the local area. Eskom has defined ‘local’ as within a 70-km radius of the power station. This ensures that employees do not travel long distances to work and reduces the nega- tive social effects typical of large-scale migrant labour recruitment, as the com- pany aims to keep families together, Crookes notes.

“We have also built the Marapong Construction village to provide accommodation for semiskilled workers and invested in other infrastructure, such as the upgrade of the Marapong and Lephalale sewage plants and the upgrade of the town’s electrical infrastructure. Future investments are planned to take place to further develop the area,” he notes.