Slovenia’s Šoštanj thermal power plant expects to return Unit 6 to service before the winter heating season after inspections uncovered damage in the turbine’s intermediate-pressure section.
Elevated vibration was detected shortly before the unit entered its planned summer overhaul. Engineers working with specialists from GE Steam Power subsequently identified damage in the turbine’s labyrinth section, prompting a wider technical inspection.
The affected component cannot be repaired in Slovenia and has been transported to GE’s facility in Berlin for refurbishment. The turbine’s high-pressure section is also undergoing a full inspection as a precaution against additional defects.
Commissioning tests are scheduled to begin in mid-October 2026, subject to completion of the repair and satisfactory inspection results. That timetable would allow Unit 6 to return before electricity and district-heating demand rises during the winter.
The outage has significance beyond the plant itself. Slovenia is already exposed to lower nuclear production at Krško and hydrological constraints associated with drought and high river temperatures. Delayed return of Šoštanj would increase the country’s reliance on imports during a period when neighbouring systems may face similar generation restrictions.
The repair is being carried out under the settlement agreement previously concluded between the plant and GE. The arrangement includes a long-term service contract worth approximately €110mn, covering planned maintenance, spare parts, manufacturer support and digital upgrades through 2029–2030.
The final cost of the current intervention has not been determined. The allocation of that cost will depend on the detailed terms of the settlement and service agreement, including warranties, defect responsibility and the classification of the damaged component.
The October target leaves limited schedule contingency. Any further defect discovered in Berlin or during reassembly could delay commissioning into the heating season, when the system value of the unit is materially higher.
