The most important development during calendar week 22 of 2026 was the continued structural shift in the Southeast European power system from conventional generation toward solar-led price formation. While average power prices fell across most markets, the underlying generation mix became increasingly polarized between record solar output and rapidly declining coal generation. The region is now entering the summer period with clear signs that midday oversupply and evening scarcity are becoming the dominant market characteristics.
Average HUPX baseload settled at €105.20/MWh, down €3.94/MWh week-on-week, while German prices fell more sharply to €94.90/MWh. Serbian SEEPEX averaged €105.71/MWh, becoming the most expensive market in the core SEE region, while Greece remained the cheapest at €86.77/MWh. Italy North remained structurally disconnected from the rest of the region at €123.87/MWh, maintaining a premium of almost €19/MWh over Hungary.
The defining feature of CW22 was the surge in photovoltaic generation across the region. Solar output reached a new record with peak generation of 11,251 MW, increasing by 1,590 MW week-on-week and standing more than 3 GW above the same week of 2025. Production rose across Bulgaria, Romania, Greece, Hungary and Serbia, reinforcing solar as a primary price driver.
This had immediate consequences. Daytime prices continued to weaken, with negative prices becoming a regular feature in Hungary, where HUPX recorded 12 negative-price hours. At the same time, rising prosumer generation reduced measured grid demand, pushing total regional consumption to its lowest level since May 2025 despite growing cooling needs.
The market is therefore no longer driven purely by weather-dependent demand. Instead, distributed solar generation is actively reshaping load profiles, creating artificial reductions in grid demand during daylight hours and increasing volatility in residual load.
Coal-fired generation continued its structural decline, reaching a new low across Southeast Europe. Average output fell to 3,743 MW, down 505 MW week-on-week and nearly 945 MW below last year. Serbia accounted for a large share of the decline, with coal output dropping sharply both weekly and annually.
Although Serbia still represents around 40% of regional coal generation, the direction is clearly downward. This matters because coal has historically provided price stability during evening peaks, and its reduction increases reliance on gas-fired generation for residual demand coverage.
Gas generation rose strongly to 3,608 MW, increasing by 555 MW week-on-week and reaching its highest level since early spring. Greece led the increase, while Hungary and Romania also contributed. This confirms the growing pattern where solar dominates midday pricing and gas dominates evening pricing, amplifying intraday volatility.
Although Austrian CEGH gas prices eased to €48.60/MWh, carbon prices rose to €78.83/tCO₂, reinforcing upward pressure on thermal generation costs. This strengthens the relative competitiveness of solar during daylight hours and deepens the structural spread between midday and evening prices.
Hydrology emerged as a growing concern, with regional hydro generation declining to 6,412 MW. Danube inflows were approximately 53% below historical averages, particularly affecting Serbia and Albania. Weak hydro availability adds a potential summer risk factor if cooling demand increases further.
Serbia showed the weakest regional power balance, recording a net import position of around 1,228 MW, significantly worse than the previous week. Lower coal output, reduced hydro production and weaker wind all contributed to this deterioration.
The Serbian generation mix remained heavily fossil-dependent, while consumption stayed stable at 3,268 MW. This resulted in increasing import reliance and greater exposure to regional price movements and cross-border congestion effects.
Greece, in contrast, strengthened its position as a regional exporter. Net exports reached 1,512 MW, supported by strong solar production and robust gas generation. This reinforces Greece’s emerging role as a balancing hub in Southeast Europe, particularly as interconnections expand.
Nuclear generation remained weak across the region, averaging just 3,098 MW due to planned maintenance and outages in Hungary, Romania and Bulgaria. Output was nearly 1 GW below the same period in 2025, temporarily increasing reliance on thermal and hydro resources.
Transmission flows were mixed, with increased imports from CORE markets into Southeast Europe, reflecting weaker regional fundamentals. However, Germany-to-Hungary transfer capacity remained constrained under flow-based coupling, limiting potential arbitrage flows.
Exports toward Ukraine and Moldova continued for a 35th consecutive week, although volumes declined. These flows remain structurally important for congestion management and regional price support during evening hours.
Three key structural themes emerge from CW22. First, solar has become the dominant driver of daytime pricing, with negative prices now embedded in market structure. Second, gas is increasingly the marginal evening technology, widening intraday spreads. Third, divergence is growing between weaker Serbian balances and stronger Greek export capacity.
Overall, CW22 confirms that Southeast Europe is entering a more volatile, more solar-driven, and more fragmented summer market regime, where value is increasingly determined not only by annual production but by timing, flexibility and cross-border positioning.
