North Macedonia begins €46 million hydropower plant modernisation phase

State-owned utility ESM has commenced the third phase of a major overhaul across six large hydroelectric assets in North Macedonia. The overall programme represents a €46 million capital commitment intended to rehabilitate aging electro-mechanical infrastructure, upgrade primary electrical equipment, and enhance overall operational reliability.

Modernisation of mature hydroelectric stations is a crucial mechanism for maintaining grid stability in the Western Balkans. By modernising turbine governors, generator step-up transformers, switchgear, and control systems, utility operators can recover lost efficiency and reduce unexpected forced outages. In this phase, the work is targeted to yield an additional 13.5 MW of installed capacity alongside an annual generation increase of approximately 50 GWh. The increased production is anticipated to generate at least €5 million in additional yearly revenue, providing clear financial returns alongside network benefits.

From an engineering perspective, major overhauls of hydro generation facilities require careful co-ordination between generation units and high-voltage transmission substations. Refurbishing primary plant often involves replacing or retrofitting transformer units, circuit breakers, and protection relays that have reached the end of their design life. Modernising step-up substations connected to these hydro facilities ensures that the additional 13.5 MW capacity can be delivered safely into the high-voltage grid without creating localized bottlenecking or thermal overload risks on aging switchgear.

Furthermore, integrating new control interfaces enables improved dispatchability and ancillary services support. As intermittent renewable capacity expands across the region, flexible hydro generation with modernised primary equipment becomes vital for frequency regulation and balancing services.

What this means for asset owners in the Balkans and the Black Sea region: Asset owners and network engineers in North Macedonia and surrounding markets must plan for coordinated outages and temporary transmission adjustments during station retrofits. Substation managers managing connections to retrofitted hydro plants face specific maintenance and procurement windows to upgrade switchgear, protection schemes, and transformer interfaces, ensuring that the 13.5 MW capacity expansion does not introduce secondary thermal or fault-current constraints on existing station assets.