Toshiba Corporation, in collaboration with a consortium comprising the German Voith Group and Swiss ABB, has signed contracts to repair and rehabilitate two units at Bulgaria’s Chaira pump-storage hydropower plant. Toshiba will handle repairs for unit 1, while the Voith-ABB consortium will be responsible for unit 3. The project aims to restore three of the plant’s four units by early 2026, which will generate over 600 MW of electricity in both pumping and storage modes. This is crucial for energy security, balancing the energy network, and integrating renewable energy in the region.
The Chaira plant, the largest pump-storage facility in the Balkans, has been offline since March 2022 following an incident during post-rehabilitation testing. However, unit 2 resumed operation last month after repairs. Additionally, Bulgaria’s National Electricity Company (NEK) has launched a tender for the supply and replacement of generators, turbines, equipment, and control systems for units 1 and 4.
Chaira has an installed capacity of 864 MW in generating mode and 772 MW in pumping mode, using four Toshiba-made Francis pump-turbines. It has been operational since 1995, with rehabilitation efforts beginning in 2019 following an emergency shutdown in 2018.