Calendar week 22 of 2026 saw a continued shift in the Southeast European power system toward solar-led price formation. Average prices fell across most markets, while the generation mix became more polarized between record photovoltaic output and declining coal generation. The region is moving into summer with signs that midday oversupply and evening scarcity are becoming more prominent.
HUPX baseload averaged €105.20/MWh, down €3.94/MWh week-on-week, while German prices fell to €94.90/MWh. Serbian SEEPEX averaged €105.71/MWh, making it the most expensive market in the core SEE region. Greece was the cheapest at €86.77/MWh, and Italy North remained structurally disconnected at €123.87/MWh, nearly €19/MWh above Hungary.
Photovoltaic output sets new records and pushes daytime pricing lower
The defining feature of CW22 was a surge in photovoltaic generation across Southeast Europe. Regional solar output reached a new record peak of 11,251 MW, up 1,590 MW from the previous week and more than 3 GW higher than the same week of 2025. Solar generation increased in Bulgaria, Romania, Greece, Hungary and Serbia.
Daytime pricing weakened further as negative prices remained a regular feature in Hungary. HUPX recorded 12 negative-price hours, compared with 15 hours in the previous week. Prosumer production also reduced measured grid demand as temperatures rose and cooling demand began to emerge.
Total regional consumption fell to the lowest level since May 2025 despite rising temperatures. The market impact described in transmission system data indicates that rooftop solar is suppressing grid consumption during daylight hours. This points to an evolving driver beyond weather-driven demand changes.
Coal declines further as gas rises for evening coverage
Coal-fired generation reached a new historical low across Southeast Europe in CW22. Average regional coal output fell to 3,743 MW, down 505 MW week-on-week and almost 945 MW below the same period last year. Serbia recorded the largest weekly decline, with coal generation down 371 MW versus the previous week and down 585 MW year-on-year.
Serbia still accounted for about 40% of coal generation in Southeast Europe, but the trend is described as clearly downward. The reduction is attributed to weaker demand, stronger solar output and operational limitations across lignite fleets. Coal’s decreasing role matters because it historically provided price support during evening peaks.
As coal output falls, markets increasingly rely on gas-fired generation after solar sunset. Gas-fired generation rose sharply to 3,608 MW, up 555 MW week-on-week and reaching its highest level since early April. Greece accounted for much of the increase, with Hungary and Romania also contributing.
A pattern visible throughout spring 2026 was reiterated: solar increasingly determines midday pricing while gas determines evening pricing. The outcome described is greater intraday volatility rather than consistently high or low prices across sessions. Austrian CEGH gas eased to €48.60/MWh, while carbon prices rose to €78.83/tCO₂, their highest level since February.
Hydropower weakness and country-level balance shifts
Hydro performance was another notable feature of CW22, with regional hydro generation declining to 6,412 MW. Danube inflows remained significantly below seasonal norms, at approximately 53% below historical averages for this period. Weak hydro output was particularly noted in Serbia and Albania.
For the rest of summer, hydrology is highlighted as a key market risk for July and August. Lower reservoir levels combined with stronger cooling demand could increase dependence on gas-fired generation during those months. The risk is described as partially masked at present by exceptional solar performance.
Serbia’s power balance deteriorated most sharply among countries in CW22. Serbia recorded a net import position of approximately 1,228 MW, worsening by more than 600 MW week-on-week and ranking among the weakest levels ever recorded in the report. The change reflected lower coal generation, reduced hydro output and weaker wind production.
Serbian generation mix during CW22 comprised about 1,278 MW coal, 840 MW hydro, 170 MW solar and 25 MW gas, with limited wind contribution . Domestic consumption stayed relatively stable at 3,268 MW, increasing import dependence as a result . The report also links Serbia’s reduced export capability during summer peaks to slower solar growth compared with Romania, Bulgaria and Greece.
Greece exports at high levels while nuclear stays weak
Greece strengthened its position in CW22 through high net exports averaging 1,512 MW. Strong solar generation, substantial gas-fired output and improving transmission utilization supported aggressive exports despite rising domestic demand . This reinforced Greece’s role as a balancing hub within Southeast Europe.
Nuclear remained unusually weak across the region during CW22. Regional nuclear output averaged only 3,098 MW, among the lowest levels ever recorded due to planned maintenance in Hungary, Romania and Bulgaria plus several unplanned outages . Nuclear generation was almost 1 GW below the same week of 2025.
The report notes that as reactors return gradually during the second half of summer, additional baseload supply could place downward pressure on regional prices and reduce gas burn requirements . Transmission dynamics were described as mixed across flows into and within the region.
Cross-border flows show mixed constraints as summer approaches
Imports from CORE markets into Southeast Europe increased substantially and reached a three-week high due to weaker regional fundamentals . In contrast, Germany-to-Hungary transfer capability under flow-based market coupling remained extremely constrained and among the weakest levels observed since 2024 .
The region maintained positive exports toward Ukraine and Moldova for a 35th consecutive week, although volumes declined versus earlier weeks . These exports continued to influence congestion patterns and support regional prices during critical evening hours.
CW22 themes point to shifting value capture into summer demand season
The outlook for June and summer 2026 highlights three structural themes emerging from CW22 . First, solar has become the dominant driver of daytime price formation across Southeast Europe, with negative pricing embedded in market structure rather than occasional behavior . Second, gas is increasingly marginal in evening periods, widening spreads between midday and evening prices.
The third theme contrasts Serbia’s deteriorating generation balance with Greece’s strengthening export position . For investors evaluating renewable projects, CW22 is described as indicating that project value depends not only on annual MWh production but also on capturing value during evening peak periods . Solar-only assets face growing cannibalization risk while solar-plus-storage and flexible gas-backed portfolios are described as becoming more strategically valuable as summer demand season approaches .
