South Africa’s first self-build Main Transmission Substation (MTS), by an Independent Power Producer (IPP), has been completed and energised on 5 April 2025. The Koruson 400/132 kV MTS outside Noupoort in the Northern Cape, has been designed and constructed to connect 1.5 GW of renewable energy to the national grid.
The project has been developed by a consortium led by EDF Renewables, together with partners, H1 Holdings, Gibb-Crede, and a local community trust. The consortium is also developing the adjacent Koruson 1 cluster of projects, which will connect to the grid through the MTS, as part of Round 5 of the IPP Office’s Renewable Energy Independent Power Producer Procurement Programme (REIPPPP).
The MTS, which is integrated into an existing 400 kV overhead line, will provide the infrastructure for the renewable energy farms to complete their respective connections to the grid and start exporting energy.
“This is the first greenfield transmission substation in more than seven years to be connected to the grid, and it is the first greenfield transmission substation that is a full self-build, i.e. developed, financed, engineered, constructed, and commissioned by an Independent Power Producer. It is also the first time that the National Transmission Company of South Africa (NTCSA) has approved a self-build scope of works of this magnitude,” said Tshepo Tshivhasa, Head of Grid Engineering at EDF Renewables.
Phase 1 of the energisation will see the Koruson 1 project connect three Wind Energy Facilities (WEF’s), totalling 420 MW, to the National Grid. In Phase 2, the neighbouring Envusa Energy Koruson 2 project, will connect two WEF’s and a solar farm, totalling 520MW, to the National Grid. Each of the individual renewable energy facilities will have its own distribution connection, consisting of 132kV overhead lines and Eskom switching stations, built under a self-build agreement with the national grid operator.
“What makes this MTS unique is the implementation of a full suite of latest Phase 6 protection, control, and automation schemes, enhancing operational reliability and efficiency, some of which was specifically developed as part of this project. Additionally, the MTS integration into the existing transmission network alters grid dynamics, requiring modifications such as the replacement of two 400 kV towers with new 400 kV transposition towers, to ensure compliance with the latest operational standards,” said Carl Wlotzka, Senior Project Manager, EDF Renewables.
“With advancements in technologies and the private sector taking on what typically used to be a grid operator project, one can expect to encounter challenges that need to be overcome. EDF Renewables, its contractors, and the national grid entity, continued to push through the challenges and table solutions to bring realisation,” said Wlotzka.
“The entire team has worked extremely hard and is incredibly proud to be part of this ‘first of its kind’ project, which will lay the foundations for future self-build (and NTCSA) projects in South Africa. This project marks a significant step in strengthening South Africa’s renewable energy infrastructure while maintaining grid stability and efficiency,” said Tristan de Drouas, CEO of EDF Renewables.
