Name and Location
Ingula pumped-storage scheme project, on the border between the Free State and KwaZulu-Natal provinces, South Africa.

Client
Eskom.

Project Description
The Ingula pumped-storage scheme, located within the Little Drakensberg mountain range, 23 km north-east of Van Reenen’s Pass, will comprise an upper dam (Bedford) and a lower dam (Braamhoek). The upper reservoir site is located in the Free State and the lower reservoir site in KwaZulu-Natal. The escarpment forms the border between the two provinces.

The distance between the upper and lower reservoirs will be 4.6 km, with an elevation difference of about 470 m.

The reservoirs will be connected through underground waterways and the underground powerhouse complex, which will house four 333 MW pump turbines with a total capacity of 1 332 MW, a machine hall, a transformer hall and associated tunnels, shafts and caverns.

The twin headrace waterways, consisting of concrete and steel-lined headrace tunnels, pressure tunnels and shafts, will link the upper reservoir with the pump turbines. The draft tubes, concrete-lined surge shafts and a single concrete-lined tailrace tunnel will connect the pump turbines to the lower reservoir.

The upper reservoir is a concrete-faced rock-fill embankment dam, 41 m high, with a total capacity of 22.4-million cubic metres and an active water storage volume of 19.2-million cubic metres. The 39-m-high lower dam comprises roller-compacted concrete, with a total capacity of 26.3-million cubic metres and an active storage volume of 21.9-million cubic metres.

The scheme will be operated on a weekly cycle and will have an overall cycle efficiency of 78%.

Value
R25.9-billion. As at December 31, 2013, R18.8-billion had been spent.

Duration
The pumped storage scheme is planned to be fully operational in 2015.

Latest Developments
Eskom reported the following progress in March:

• Owing to the fatalities in the inclined high-pressure shafts (IHPS), all work on the project as a whole was suspended. Further delays could arise as new equipment is manufactured, installed and licensed for construction in these shafts and safer methods of construction are implemented in all shafts, including the surge chambers.
• Remaining work on the Transformer hall has been completed, including the civil construction of Blocks 3 to 5 and the battery room to Block 2.
• Construction of the control room’s east walls have risen to intermediate level, the transversal walls have been completed and the west walls have been completed up to roof level.
• Remaining work on the tailrace tunnel comprises the construction of bifurcations, drilling and grouting, finishing works to the tunnel and the construction of plugs to MAT and the construction audit.
• Main underground works completed include the excavation and rock support works; civil works and the installation of the turbine units and other mechanical items are under way. Civil works include the placement of about 500 000 m3 of concrete. The civil works activity remains critical in terms of the overall project completion, owing to access requirements for the transformer and electrical packages. The intake and outlet structures have been completed.
• Generator motor transformers 3 and 4 are in final position in the transformer hall.
• The double-storey, concrete-framed administration building, which has a large basement that will have direct access to the main tunnel into the underground power station is being built concurrently with a single-storey visitor centre, which includes a small office wing, a cinema, various display halls, an auditorium and facilities. The current completion date is June 2014.

Key Contracts and Suppliers
The Braamhoek Consultants Joint Venture (BCJV), consisting of Gibb, Knight Piésold and SSI (civil, mechanical and electrical engineering, detailed design, tender documentation, design monitoring and construction supervision); Murray & Roberts (exploratory tunnel); Grinaker-LTA (access roads); CMI JV, comprising CMC di Ravenna, PG Mavundla and Impregilo (underground civil works); Afriscan (water supply, sewage treatment, small access roads and building temporary Eskom offices); B&E Quanza Group (aggregate quarry); Acer [Africa] (environmental consultants); Braamhoek Dam JV (BDJV), comprising Concor Roads & Earthworks, Wilson Bayley Holmes-Ovcon, Edwin Construction and Silver Rock (dam contract); Voith Siemens Fuji Hydro Power Generation (main generating plant); Deutsche Bank (R1-billion loan); Voith (mechanical auxiliary plant, turbines and generators); ABB (electrical balance of plant); NCC Environmental Services (independent environmental control officer services); Konecranes (heavy-duty cranes); Letacla (fibre-optic communications) and Siemens (generator transformers).

On budget and on time?
The first 333 MW unit was initially expected to be commissioned by January 2013; however, it will be commissioned only during the first quarter of 2015.

Contact Details for Project Information
Eskom executive project manager Carel Stoop, email StoopCJ@eskom.co.za
Ingula Visitors Centre, tel +27 36 342 3122 or email fifi.meyer@eskom.co.za.
ABB, tel +41 43 317 6480 or fax +41 43 317 6482.
Gibb, tel +27 11 519 4600 or fax +27 11 807 5670.
BDJV (Concor Roads & Earthworks), tel +27 11 495 2222.
CMI Mavundla JV, tel +27 36 638 6000.
Eskom media desk, tel +27 11 800 3304/3309/3343/3378, fax +27 11 800 3805 or email mediadesk@eskom.co.za.
Impregilo, tel +39 02 4442 2115.
Voith Siemens Hydro Power Generation, tel +49 7321 370 or fax +49 7321 37 6180.
NCC, tel +27 21 702 2884, fax +27 86 555 0693 or email info@ncc-group.co.za.
Konecranes, tel +27 11 864 2800.