In Southeast Europe, day-ahead electricity prices softened in Week 24 while generation patterns shifted. Renewable output rose and wholesale prices declined across most markets. At the same time, hydropower generation fell sharply, changing how the system met balancing needs.
Hydropower contraction across SEE
Regional hydropower production decreased by 300.2 GWh, or 7.5%, to 3.70 TWh. Türkiye accounted for the largest share of the decline, with hydro output down by 229 GWh, or 8.6%. This represented more than three-quarters of the total regional reduction.
Bulgaria also saw a substantial fall in hydropower generation, dropping by 42.9 GWh, or 21.8%. Greece, Italy, Romania and Serbia recorded smaller reductions compared with Türkiye and Bulgaria. The combined declines reduced available hydro generation across the region.
Thermal generation rises as coal and lignite expand
Total thermal generation in Southeast Europe increased by 362.6 GWh, or 8.7%, reaching 4.52 TWh. Coal and lignite output rose by 420.6 GWh, or 24.4%, to 2.14 TWh. Gas-fired generation declined by 58.0 GWh, or 2.4%, to 2.38 TWh.
The change in dispatch translated into a shift in the marginal fuel mix during the week. The region absorbed higher demand alongside lower hydro availability through increased coal and lignite generation rather than higher gas output.
Country contributions and divergences from regional trends
Türkiye added 260.6 GWh of coal-fired generation during the period. Italy increased output by 81.2 GWh, while Serbia contributed an additional 66.0 GWh. Bulgaria and Romania also recorded gains in thermal production.
Greece diverged from the broader pattern as its thermal generation fell by 6.3% despite rising electricity demand. Reductions in lignite and gas-fired output outweighed stronger consumption in Greece.
Croatia followed a different trajectory, with hydropower increasing by 43.5%. This contrasted with hydropower declines recorded across most neighbouring markets during Week 24.
Implications for balancing and market participants
The week reflected how system flexibility was sourced when hydropower conditions weakened. Renewables were associated with softer pricing, but thermal dispatch increased as hydropower output fell.
The shift also matters for commercial decision-making tied to renewable contracting and risk assessment. Lower spot prices did not necessarily coincide with reduced balancing risk or lower system emissions for industrial consumers, traders, and financial institutions evaluating renewable PPAs.