Electricity.Trade’s May 2026 monthly market analysis shows that Southeast Europe is moving away from a simple baseload model and toward a flexibility-driven power market. The old logic was built around coal, nuclear, hydro and imports. The new logic is more complex: renewables are rising, hydro is volatile, gas still shapes marginal prices, imports are increasingly important, and hourly spreads are becoming more valuable.
May captured this transition clearly. Renewable output increased in most analysed markets, led by Bulgaria at 34.19%, Romania at 26.57%, Greece at 15.88%, Hungary at 9.56% and Italy at 9.22%. Yet average prices still rose across most European SEE markets. That means renewable growth is changing price shape but not automatically reducing monthly price levels. Flexibility is becoming the missing variable.
Hydro showed the same point from another angle. Greece’s hydro output rose 40.80%, helping the country become a net exporter of 874.20 GWh. Bulgaria’s hydro increased 7.30%, supporting net exports of 258.65 GWh. But Serbia’s hydro fell 31.68%, Croatia’s 21.17%, Hungary’s 29.10% and Romania’s 6.96%, pushing or keeping those markets in import-dependent positions. Hydro is therefore not just renewable energy. It is dispatchable flexibility, and its monthly variation can redraw the regional trade map.
Gas remained the marginal-cost anchor. TTF front-month futures averaged €47.26/MWh, keeping gas-fired generation expensive enough to support power prices, especially in Italy and Greece. Italy’s mix still included 34.07% gas, while Greece had 28.11% gas. Even where solar and wind output are strong, gas can continue to set prices in residual hours.
This is where the market trend becomes investable. SEE needs batteries, pumped hydro, interconnectors, demand response, flexible industrial consumption, better forecasting and more sophisticated PPAs. Baseload generation will remain important, especially nuclear in Bulgaria and Hungary and coal in Serbia, but the value pool is shifting toward assets and contracts that can manage variability.
Electricity.Trade should present May as evidence of a regional market moving into its next phase. The winners will not only be those with cheap generation. They will be those able to shape, store, verify, transport and hedge electricity across time and borders. In Southeast Europe, flexibility is becoming the new trading premium.
