Electricity.Trade reported that its May 2026 market review shows Southeast Europe moving toward a more advanced hourly trading environment, where monthly average prices no longer capture market dynamics. Wholesale prices stayed elevated across the region, including Italy at €119.35/MWh, Romania at €109.56/MWh, Hungary at €106.51/MWh, Croatia at €103.58/MWh, Bulgaria at €101.07/MWh, Serbia at €96.63/MWh and Greece at €88.98/MWh. Within that setting, the review said the key signals increasingly came from hourly price movements rather than monthly averages. Renewable-rich daytime periods were associated with downward price pressure, while evening hours showed stronger pricing as demand recovered and solar output declined.
Daytime renewable output and evening demand shape the hourly curve
The same review linked changes in intraday behavior to expanding renewable generation across most Southeast European markets in May. Bulgaria recorded a 34.19% increase, followed by Romania at 26.57%, Greece at 15.88%, Hungary at 9.56%, Italy at 9.22%, Serbia at 2.90% and Croatia at 0.13%. As solar and wind penetration rises, the report said these resources are reshaping intraday market behaviour through shifts in when lower-cost electricity is available. It also noted that midday periods increasingly concentrate renewable supply, while evening pricing remains supported by demand peaks, reduced solar availability and the need for flexible generation.
Storage value varies with national generation mixes and cross-border flows
The review said the changing hourly pattern increases the role of battery storage as a trading tool alongside broader energy transition developments. It highlighted that storage opportunities differ between countries due to how each system balances renewables, baseload generation and external supply needs. Greece, with 57.19% renewables in its May electricity mix, became a major electricity exporter as strong renewable and hydro output supported cross-border flows. Bulgaria combined 29.35% renewables with 32.59% nuclear generation, pairing baseload stability with greater renewable-driven price variation.
For Serbia and Croatia, the report pointed to different constraints affecting market structure and trading conditions. Serbia’s generation mix included 56.99% coal and lignite, but weaker hydropower and stronger demand increased reliance on imports. Croatia faced even higher external dependence, with net imports representing 43.78% of its electricity mix in May.
Gas-linked marginal costs continue to influence spreads
The natural gas market remained a factor behind regional electricity spreads in the review’s assessment of May conditions. TTF front-month gas futures averaged €47.26/MWh and generally traded within the €44–50/MWh range during the month. The report said these levels kept gas-fired generation costs high enough to support evening electricity prices even when renewables pushed daytime prices lower. It added that gas-linked marginal costs continued to act as a price floor during periods of tighter supply and higher demand.
Trading strategy shifts toward managing daily price profiles
The review characterized May 2026 as a shift in Southeast European power trading strategy toward managing the daily electricity curve rather than focusing only on cross-border price differences. It said opportunities increasingly depend on how prices move across hours as scarcity persists during non-solar periods. Alongside battery storage, it cited pumped hydro and flexible industrial demand as relevant tools under the evolving hourly market environment.
The report also referenced virtual PPAs and advanced intraday trading strategies as approaches expected to become more valuable as SEE markets integrate more renewable energy while continuing to reflect scarcity outside solar hours.