Electricity.Trade’s May 2026 market review says Southeast Europe is moving into a more advanced hourly trading environment, where monthly average prices do not fully reflect market dynamics. The review reports that 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. It adds that the key trading signals increasingly came from hourly price movements rather than monthly averages.
According to the review, renewable-rich daytime periods contributed to downward price pressure in May. Evening hours continued to show stronger pricing as demand recovered and solar output declined. This pattern is described as strengthening the case for battery storage used in trading rather than only as part of the energy transition.
Renewables growth reshapes intraday price patterns
The review links the shift in trading signals to changes in generation during May across several Southeast European markets. It reports renewable generation increases of Bulgaria up 34.19%, Romania up 26.57%, Greece up 15.88%, Hungary up 9.56%, Italy up 9.22%, Serbia up 2.90% and Croatia up 0.13%. As solar and wind penetration rises, it says these resources are changing intraday market behavior.
The report states that lower-cost renewable electricity is increasingly concentrated in midday hours. It also says evening periods remain supported by demand peaks, reduced solar availability and the need for flexible generation.
Country-by-country differences in storage-relevant conditions
Electricity.Trade’s data also highlights differences in how storage opportunities may vary between countries based on system structure. In Greece, it reports renewables accounted for 57.19% of the May electricity mix, alongside strong renewable and hydro output that supported cross-border flows. In Bulgaria, it says renewables were 29.35% while nuclear generation reached 32.59%.
For Serbia, the review reports coal and lignite made up 56.99% of its generation mix. It says weaker hydropower and stronger demand increased reliance on imports during May. For Croatia, it reports net imports represented 43.78% of its electricity mix.
Gas prices underpin evening spreads
The review describes natural gas as continuing to influence regional electricity spreads through marginal pricing effects tied to gas-fired generation costs. It reports TTF front-month gas futures averaged €47.26/MWh in May and generally traded within the €44–50/MWh range. It says this level kept gas-fired generation costs high enough to support evening electricity prices.
The report adds that even when renewable output pushes daytime prices lower, gas-linked marginal costs continue to act as a price floor during periods of tighter supply and higher demand.
Implications for power trading strategies in May 2026
The review characterizes 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 lists battery storage alongside pumped hydro, flexible industrial demand, virtual PPAs and advanced intraday trading strategies as areas expected to become increasingly valuable.
It ties this expectation to ongoing integration of more renewable energy across SEE while prices continue to reflect scarcity during non-solar hours.
