Stortemelk Hydropower
Stortemelk hydropower project in South Africa
The award-winning Stortemelk hydropower project, located in the Free State, was the first time an EPCM contractual structure was used under the South African REIPP programme under a project finance structure. Zutari provided EPCM services, among other services, for the single 4.4 vertical Kaplan turbines.
The Stortemelk hydropower project is the implementation of one of the three projects included in the Botterkloof and Merino II feasibility study by Zutari for Stortemelk Hydro (Pty) Ltd, with REH as the project developers. The turbine was installed at the Botterkloof Dam on the Ash River near Clarens in the Free State province of South Africa.
The power station had to be constructed between two existing dams without affecting their operations and stability. The power station required deep excavations through the Botterkloof Dam embankment for the intake and concrete penstock but even deeper between the Botterkloof Dam and Boston A Dam spillways for the power station.
Zutari was appointed as the EPCM contractor by Stortemelk Hydro (Pty) Ltd, A SPV owned by Renewable Energy Holdings (Pty) Ltd (REH), who are also the owner of the two existing Bethlehem hydro power stations, namely the Merino and Sol Plaatje power stations, also designed by Zutari. As EPCM contractor, Zutari was responsible for the entire detailed design, construction supervision, ECO monitoring, contract administration and programming, as well as the health and safety oversight.
Through Zutari’s multidisciplinary capability, we were able to provide all necessary services in-house for our client, which helped to convince stakeholders such as lenders, lender’s engineers, and other international investors that the EPCM approach, rather than the typical EPC approach, was the most appropriate solution without increasing the overall project risks.
Through Zutari’s multidisciplinary capability, we were able to provide all necessary services in-house for our client
Zutari packaged our services in a cost-effective manner to Stortemelk Hydro, and implemented innovative solutions in the design to maintain the construction value within budget. Zutari proposed a very compact solution comprising single vertical double regulated Kaplan turbine (Saxo type) with the short penstock route optimised to avoid endangering the existing structures.
REH, the project developer, with the assistance of the Zutari team, managed to obtain all necessary approvals to reach financial close to allow construction to proceed, which commenced in September 2014. The project was completed on time and commissioned in June 2016 without touching the contingency budget.
REH’s managing director Anton-Louis Olivier said: “This project was made possible by the ongoing relationship between ourselves and Zutari. The Zutari team understands the context of small hydro and private project development, which allows for clear management of the complex and highly regulated development process as well as efficient risk allocation during development and construction.”
The local municipality Dithlabeng benefited from the employment opportunities and local procurement. The project received the 2017 Award for Architecture from the South African Institute of Architects for the Free State Region, a commendation from Consulting Engineers South Africa (CESA), the 2017 Award for the Small-Scale Sustainable Energy Project from the Africa Utility Week and the Best Project 2018, as well as a special mention in the Innovation Category by Construction World, amongst others, and it contributes to South Africa’s renewable energy goals.
The entire system is fully automated and the owner has a team of one plant manager, two technicians, and three semi-skilled technicians operating his three plants along the Ash River. The plant, which is connected to the grid, provides electricity to approximately 3,000 homes.
The developer has further appointed Zutari to complete a bankable feasibility study for additional projects in Zambia. Zutari is also involved in a final development on the Ash River downstream of Stortemelk, which is ready for construction and awaiting the REIPPP to restart.
The Zutari team understands the context of small hydro and private project development
*The Aurecon Africa business has been officially renamed Zutari as at 21 July 2020. Zutari acquired Aurecon Middle East on 20 November 2020.
