Hydropower generation moved in sharply different directions across Southeast Europe in the week to September 13. Regional hydropower output declined 2.1% to 2.81 TWh, while individual country outcomes diverged. The changes strengthened electricity supply in Croatia and Serbia but increased pressure on power systems in Bulgaria and Greece.
Regional hydropower changes and wholesale price impacts
In Croatia, hydropower generation rose 53.7%. The increase came as wind and solar generation fell 24.3% and thermal output declined 17.6%. Even with stronger domestic hydro availability, Croatia’s wholesale electricity price increased 8.5% to €176.34/MWh.
Serbia recorded an 18.2% rise in hydropower generation. With electricity demand lower, the additional hydro output helped Serbia keep a marginal net export position despite a 5.1% decline in thermal production. Serbia’s wholesale price still rose 11.1% to €155.70/MWh.
Weaker hydro in Bulgaria and Greece
Bulgaria saw hydropower generation fall 27.4%, the largest decline among the monitored markets. The shortfall was offset by a 17.6% increase in thermal generation and slightly higher wind and solar output, supporting a 38% increase in net exports. The shift reflected a weaker hydro contribution relative to other generation sources.
Greece recorded a decline in hydropower production of 11.2%, to 58.95 GWh. The reduction occurred alongside weaker renewable and gas-fired generation, while domestic electricity demand fell substantially. Greece reduced its wholesale price and increased exports as demand weakened.
Romania’s higher hydro output alongside other generation
Romania increased hydropower generation by 2.5%. The rise coincided with a strong increase in wind output and higher thermal production. As a result, Romania reduced its net imports by almost half.
Hydropower remains a flexible generation resource in Southeast Europe, enabling producers to respond relatively quickly to changes in electricity prices and renewable output. Its role becomes more significant when solar generation declines during evening hours or when wind production changes unexpectedly.
Elevated by Virtu.Energy