A heatwave scenario for SEE should start from the Week 25 demand signal. Regional electricity consumption rose 3.1%to 16.34 TWh, before the peak summer period had fully developed. That suggests July and August demand could move materially higher if temperatures rise across Italy, Greece, Serbia, Hungary, Romania, Croatia and Bulgaria at the same time.
The price effect would not be linear. A moderate increase in demand can be absorbed when hydro, wind and imports are available. A heatwave becomes dangerous when cooling load peaks in the same hours that solar output begins to fall. That is where the evening block becomes exposed, especially in markets with limited storage and high import dependency.
Italy would remain the first stress point. It already averaged €127.69/MWh in Week 25 and imported 1.12 TWh net. A heatwave combined with lower hydro and weak wind would reinforce Italy’s import pull and push pressure into the Adriatic and Central European-linked corridors. Croatia would also be exposed because its demand rose 9.7% in Week 25 and net imports increased 26.0%.
Hungary and Romania would face a different stress. Their prices already moved above €100/MWh, with Hungary at €109.16/MWh and Romania at €104.84/MWh. During a heatwave, these markets could reprice sharply if Central European conditions tighten at the same time.
Serbia’s risk is more nuanced. Hydro recovery and coal availability can soften domestic stress, but SEEPEX can still rise if neighbouring markets pull exports. A hot week with weak regional wind could lift Serbian prices even without a domestic supply shock.
The summer stress case is therefore not simply “more demand means higher prices.” It is more precise: heat matters most when it collides with weak evening flexibility.
