Reflecting the abundance of water in Indonesia, the Malea Hydroelectric Power Plant was launched as part of a programme in 2014 by the country’s administration to boost hydroelectric supply of electricity to homes and businesses, as well as boost industrial growth.
Being built near the villages of Randanbatu, Makale and Tana Toraja, in the South Sulawesi province, it has an installed capacity of 2x45 MW (Stage 1) and will have 3x75 MW (future Stage 2).
Aurecon was engaged by a syndication of two banks, Bank Negara Indonesia and Bank Rakyat Indonesia, to carry out the due diligence on the project.
Malea is one of multiple projects under the programme to meet Indonesia’s increasing demand for electricity and enable the state to take steps to achieving energy independence.
The plant uses run-off water from the Sadang River, located in Tana Toraja, which has a discharge rate of 129.9 m³/sec and the potential to generate large amounts of hydroelectricity.
The hydroelectric plant has a 9.4-kilometre-long, mainly unlined, headrace tunnel was designed to carry the run-off water from the river to an air cushion surge chamber pressure handling system, which then feeds the water to two Francis turbines in a semi-underground powerhouse, for power generation.
Power is exported to the grid of the state-owned electricity company (PT Perusahaan Listrik Negara) at Makale, through a newly constructed, 20-kilometre-long, double circuit 150-kV transmission line. From there, it powers approximately 70 000 homes and small-to-medium scale business.
Part way through the design development stage, the surge protection system changed from a conventional type into an air cushion surge chamber (ACSC), a relatively new technology that fitted better into the project’s budget and timeline.
Aurecon engaged with the firm designing the system to assess the supply, installation and operational risks in order to complete a full due diligence of the solution. The system was analysed and approved for use.
Stage 1 of the Malea Hydroelectric Power Plant is complete and is an important step in harnessing the abundance of water in Indonesia to produce renewable power and reduce the country’s carbon emissions.