Renewables-led correction hits day-ahead power
South-East European power markets moved sharply lower in Week 17 (20–26 April), as strong renewable output coincided with weaker demand and pulled prices down across the region. The same period also saw gas markets firm on renewed geopolitical risk, which helped lift the floor for forward power pricing. For grid planners and developers, the episode underlined how quickly weather-driven generation swings can propagate into market signals that affect project bankability and dispatch assumptions.
Day-ahead prices posted double-digit declines, with the steepest weekly drops in Croatia and Hungary. Weekly averages fell to €72.92/MWh (-30.3%) in Croatia and €80.31/MWh (-27.3%) in Hungary, while Romania eased to €86.99/MWh (-17.5%) and Bulgaria to €81.82/MWh (-16.8%). Greece declined to €78.61/MWh (-16.2%), and Serbia saw a more moderate fall to €80.41/MWh (-11.6%), reflecting comparatively tighter system conditions.
Italy remained the regional premium market at €109.12/MWh, even as its week-on-week trend softened. The correction also tracked a broader European move, with Germany, the Czech Republic and Slovakia seeing declines exceeding 40%. France stood out with a collapse to €7.62/MWh (-89.3%), consistent with extreme oversupply conditions linked to high nuclear and renewable output, while Iberian markets stayed broadly stable around €50/MWh.
Demand softens while wind volatility dominates supply
Operationally, the demand side turned down across SEE, reversing the prior week’s growth trend. Electricity consumption declined by -2.6% week-on-week, with Italy and Türkiye leading the contraction at -4.1% and -3.9%, respectively, and Hungary also down -4.1%. Romania and Greece recorded increases of +6.5% and +3.2%, pointing to localized demand recovery tied to weather patterns and short-term activity.
Supply dynamics were dominated by wind weakness rather than a broad-based renewable collapse. Total variable renewable output across SEE fell by -11.3%, driven by a -29.3% drop in wind production, while solar output rose by +8.8% and partially offset the decline. The largest wind reductions were recorded in Türkiye (-40.4%), Croatia (-22.9%) and Greece (-16.3%), reinforcing the need for developers to stress-test interconnection studies against seasonal resource variability.
Hydropower remained broadly stable overall at -1.5%, though national outcomes diverged sharply. Croatia posted a +145.2% increase, while Serbia fell by -23.4%, Bulgaria by -27.4%, and Romania by -9.8%. Thermal generation decreased by -6.4%, led by a -14.3% drop in gas-fired output, while coal generation rose modestly by +3.3%, indicating continued fuel switching in response to gas price dynamics.
Cross-border rebalancing raises import dependence
Cross-border flows expanded during the week, with the region’s net import position rising by +39.7%. Greece and Romania shifted from net export to net import positions, while Serbia moved deeper into import territory as balancing needs increased under lower renewable output from wind and softer demand profiles elsewhere.
Italy remained the dominant net importer throughout the period, while Croatia strengthened its export position and Hungary’s surplus narrowed rather than widening further. For transmission infrastructure stakeholders, these flow changes are a reminder that grid modernization priorities—such as congestion management, cross-border coordination, and dynamic operational planning—can materially affect realized value for new wind and solar projects.
Liquidity remains concentrated; price signals stay unstable
Market liquidity was highly concentrated in a small number of trading hubs during Week 17. Weekly traded volumes reached 20,340 GWh in Italy, far ahead of Greece at 3,560 GWh, Bulgaria at 2,450 GWh, and Hungary at 2,260 GWh.
Serbia continued to show limited liquidity with only 110 GWh traded over the week, underscoring structural constraints in regional price formation that can complicate hedging strategies for developers preparing EPC packages or long-term offtake structures.
Gas tightness lifts TTF; LNG flows show uneven regional utilization
In gas markets, TTF front-month futures extended gains early before stabilizing through Week 17. Prices rose from €40.29/MWh to a peak of €44.86/MWh, with a weekly average of €43.03/MWh (+1.3% week-on-week). By April 27, prices eased slightly to €44.65/MWh, suggesting consolidation near the mid-€40/MWh range.
The upward pressure was linked to renewed geopolitical uncertainty involving stalled US-Iran negotiations and escalating tensions around the Strait of Hormuz. Disruptions already altered the global gas balance: estimates pointed to a cumulative loss of around 120 bcm of LNG supply between 2026 and 2030, equivalent to roughly 15% of expected global supply growth—delaying anticipated market loosening by up to two years.
LNG flows into Europe also showed mixed signals across entry points relevant for system balancing studies and fuel procurement planning for thermal fleets supporting renewables integration. Greece recorded a +22% increase in LNG inflows to 663.83 GWh, while Italy maintained dominance with 4,334.7 GWh as an entry point; Croatia saw a sharp decline of -60.8%, highlighting volatility in infrastructure utilization.
Implications for project readiness across wind, solar and storage-linked grid needs
The combination of weakening wind output, shifting cross-border flows and firming gas prices suggests that short-term power corrections remain plausible even when longer-run structural support for higher volatility persists across SEE power markets.
For developers advancing wind and solar projects through technical studies toward permitting milestones and EPC preparation—often alongside battery energy storage system concepts aimed at smoothing variability—Week 17 highlights why grid modernization assumptions must be updated frequently using operational data from both power generation mixes and interconnector behavior.
Looking beyond Week 17 alone, early indications for Week 18 pointed to renewed upward pressure: day-ahead prices on April 28 rebounded across SEE between €97.01/MWh in Greece and €112.66/MWh in Hungary, reinforcing that downside may not remain stable when system conditions tighten or fuel-linked marginal pricing strengthens.