Southeastern Europe is witnessing a significant shift in its energy landscape, as gas has re-emerged as a critical component in electricity pricing dynamics. This development comes after years of efforts to reduce dependency on gas, particularly in the context of the region’s energy transition towards renewables and decarbonization.
Data from early May 2026 indicates that gas-fired generation across the broader Hungary and Southeastern Europe (HU+SEE) system increased by approximately 362 MW. This uptick occurred despite a decline in total regional electricity demand by around 1,018 MW. Concurrently, nuclear output saw a sharp decrease of 1,686 MW, while coal generation fell by 260 MW and hydro output weakened by 357 MW.
The interplay between these factors has reinstated gas into a marginal balancing role at a time when renewable energy sources are facing volatility and traditional thermal generation is becoming less reliable. The immediate market response was evident, with prices on various exchanges reflecting this shift: Romania’s OPCOM surged to €115.88/MWh, Hungary’s HUPX reached €108.62/MWh, Bulgaria’s IBEX climbed to €104.98/MWh, Croatia’s CROPEX averaged €105.77/MWh, and Serbia’s SEEPEX exceeded €101/MWh.
This surge in prices signals a departure from a demand-driven pricing structure, indicating that marginal generation scarcity is increasingly dictating electricity prices. Gas remains the most viable technology to fill this balancing gap, reinforcing its strategic importance in the region’s energy framework.
The resurgence of gas does not imply a retreat from decarbonization goals. Instead, the rise of intermittent renewable sources necessitates flexible gas generation capabilities to maintain operational stability. Countries such as Bulgaria, Greece, Romania, Serbia, and North Macedonia are rapidly expanding their solar and wind capacities; however, these sources alone cannot provide the necessary stability during periods of low production or high demand fluctuations.
Aging coal infrastructure across Bosnia and Herzegovina, Montenegro, and Serbia is also contributing to this dynamic. Facilities like RiTE Ugljevik have faced extended outages, while RiTE Gacko reported declining profitability amid environmental pressures. Additionally, nuclear generation has been hampered by maintenance issues, further exacerbating the need for reliable balancing mechanisms.
The strategic implications for gas infrastructure are profound. Projects such as the Alexandroupolis LNG terminal and the Vertical Gas Corridor are now viewed not only through the lens of reducing reliance on Russian supplies but also as essential components for maintaining stability in renewable-heavy electricity systems.
The ongoing transformation of SEE electricity markets is characterized by increasing volatility. Solar generation is accelerating rapidly; Bulgaria is emerging as a significant solar hub while Greece faces curtailment pressures. This results in an environment where daytime oversupply coexists with evening scarcity—conditions that gas can effectively bridge due to its quick ramp-up capabilities.
The importance of interconnectivity through initiatives like the Vertical Gas Corridor is becoming clearer as regional discussions among Greece, Serbia, Bulgaria, and North Macedonia highlight its role in ensuring market stability amidst declining Russian pipeline flows into Europe. With TurkStream deliveries decreasing both month-on-month and year-on-year, gas prices remain elevated due to geopolitical tensions affecting global LNG markets.
This evolving landscape presents challenges for policymakers who must balance the need for greater gas flexibility against an increasingly uncertain procurement environment. The simultaneous pursuit of renewable expansion, battery storage deployment, gas interconnection development, LNG diversification, coal phase-down strategies, grid modernization, and investment in balancing infrastructure reflects this tension.
As power trading dynamics shift from traditional metrics like hydro conditions and coal availability to factors such as gas spreads and LNG flows, the correlation between gas hubs and SEE power exchanges is strengthening once again. Average CEGH gas prices hovered around €46.64/MWh, with Greek prices near €45.22/MWh. Despite slight declines in carbon prices to approximately €74.96/t, the overall cost structure supports elevated thermal marginal pricing.
This scenario underscores a critical paradox within Europe’s energy transition: while renewables aim to reduce fossil fuel dependency long-term, short-term reliance on gas for balancing continues to grow until substantial storage and flexibility solutions are fully realized.
The implications for project financing are significant; assets previously deemed vulnerable are regaining value as balancing providers. Combined-cycle plants and hybrid systems may see stronger utilization than anticipated just a few years ago. However, pure baseload gas exposure remains risky amid rising decarbonization pressures.
Countries that successfully integrate flexible gas access with renewable generation and robust interconnections will likely achieve greater energy security and pricing stability than those reliant on single-source generation strategies.
As Greece positions itself as a regional hub through its LNG infrastructure and interconnections, Bulgaria enhances its role via storage deployment. Serbia’s geographical centrality further solidifies its strategic importance in linking Central Europe with future corridor expansions.
This evolution extends beyond electricity supply; industrial competitiveness and regional economic structures increasingly depend on reliable energy sources rather than merely low-cost options. Thus, gas emerges not as the future dominant fuel but rather as a stabilizing mechanism crucial for transitioning towards a more renewable-centric power system in Southeastern Europe.
