Montenegro’s 225 MW Pljevlja thermal power plant has returned to the grid following a transmission-related outage that required state utility EPCG to procure electricity on short-term markets. The disruption began on 2 August after a malfunction at a substation operated by CGES cut the plant’s external power supply. Electricity was restored in about 80 minutes, but the unit reconnected only during the early hours of 6 August after additional inspections and stabilisation.
Imports and domestic generation during Pljevlja unavailability
During the period when Pljevlja was unavailable, EPCG imported around 7,500 MWh per day. The estimated daily cost was €760,000, implying an average procurement cost of about €101/MWh, excluding any additional balancing, congestion or transmission effects. Domestic solar plants supplied roughly 500 MWh per day, equivalent to around 10% of Pljevlja’s normal daily output.
Hydropower provided the principal domestic replacement while EPCG postponed scheduled maintenance at the Perućica hydropower plant to preserve system adequacy. The outage period therefore shifted reliance toward hydro generation and imported electricity rather than Pljevlja output. The scale of imports reflected the gap created by the thermal plant’s absence.
Transmission fault assessment and operational responsibility
The event also underlined the link between generation and transmission assets. CGES’s preliminary assessment connected the substation malfunction to extreme weather and industrial pollution rather than an internal grid defect. That distinction may affect how EPCG and CGES assess operational responsibility.
The same assessment could also influence insurance coverage and how outage costs are allocated between parties. While electricity supply was restored within roughly 80 minutes, the generating unit required further checks before it returned to service. The timeline therefore extended beyond the initial restoration of external power.
Cost exposure and forward procurement through 2026
The financial exposure from replacement power was described as material. A ten-day interruption at the reported import rate would require approximately €7.6 million of replacement electricity, while a month-long outage under similar conditions would approach €23 million, before considering adverse price movements. EPCG has secured sufficient imported electricity to cover remaining domestic requirements through the end of 2026.
This forward procurement reduces immediate security-of-supply risk, while also potentially locking in costs that may become less attractive if Pljevlja, hydroelectric plants and new renewables generate above expectations. Pljevlja normally provides about 40% of Montenegro’s electricity generation, so its return is significant for EPCG’s trading position and cash flow.
Restart does not remove concentration risk for Montenegro’s system
EPCG said the restart enables preparation for the delayed Perućica overhaul. However, it does not address Montenegro’s structural concentration risk tied to a limited set of large generating assets. Until substantial solar, wind, storage and flexible balancing capacity enters operation, a single failure at Pljevlja or a major hydropower facility can have an outsized effect on imports and utility cash flow.
The impact can be particularly pronounced during dry and hot summer conditions when system balance depends more heavily on available generation capacity. In such periods, Pljevlja’s absence can shift Montenegro toward substantial importing within hours.
