Bulgaria's NEK EAD signs memorandum with Toshiba International Europe Ltd. to restart 864 MW Chaira pumped-storage hydropower plant
Type: Partnership · Technology: Hydro · Country: Bulgaria · Capacity: 864 MW · Announced: 2026-04-28
Bulgaria’s state-owned utility Natsionalna Elektricheska Kompania EAD (NEK EAD) signed a memorandum of understanding with Toshiba International Europe Ltd., the UK subsidiary of Japan’s Toshiba Corp., to restart operations at the 864 MW Chaira pumped-storage hydropower plant in the Rhodope Mountains near Devin. The facility, the largest of its kind in Southeastern Europe, has been offline since March 2022 following a turbine failure in Unit 4, which was attributed to material fatigue and cavitation effects. Toshiba, which originally supplied the pumped-storage turbine and generator for Unit 1 in 1994 and later expanded involvement to all four units, will conduct repair work on Unit 1 and provide technical support for Units 2, 3, and 4, including operational and maintenance services. The Chaira plant features four reversible Francis pump-turbines, each rated at 216 MW in generating mode and 197 MW in pumping mode, with Units 1 and 2 commissioned in 1995 and Units 3 and 4 in 1999. Bulgaria’s Ministry of Energy highlighted the urgent need for restoration due to aging infrastructure and the plant’s critical role in the country’s energy grid.
Counterparties
- Toshiba Corp (Parent Company)
- Toshiba International Europe Ltd (Partner)
- Natsionalna Elektricheska Kompania EAD (NEK EAD) (Developer)