Hydro remains the most underpriced risk variable in SEE power analysis. Week 25 showed why. Regional hydropower generation fell 4.7% to 3.57 TWh, and the decline helped lift thermal dispatch and electricity prices across much of the region. Solar increased, but hydro weakness still mattered because hydro provides something solar cannot: controllable flexibility.
A hydro sensitivity tracker should focus on Serbia, Romania, Croatia and Greece, with Italy added as the regional premium reference. These systems rely on hydro not only for energy, but for ramping, balancing and evening supply. When hydro availability falls, the market leans more heavily on gas, coal, imports and higher-priced balancing power.
Serbia offers the positive case. Its hydro output recovered 42.9% in Week 25, helping the country move from net imports to modest net exports. But SEEPEX still rose 9.6%, proving that domestic hydro strength can reduce physical pressure without fully insulating Serbia from regional price signals.
Romania provides the opposite case. Hydro generation fell 9.8%, reducing one of the country’s key flexibility buffers. Romania averaged €104.84/MWh and then appeared as the highest-priced SEE market in the forward day-ahead map for 24 June, at €202.95/MWh. That makes Romanian hydro sensitivity one of the most important summer indicators.
Greece and Croatia need separate treatment. Greece can offset some hydro weakness through solar, wind and gas-fired flexibility. Croatia is more exposed through imports and Adriatic corridor pricing. The tracker should not treat all hydro systems equally. Reservoir levels, inflows, pumping capability, import exposure and demand seasonality all change the price impact.
Hydro is no longer a background generation category. In SEE, it is a market-shaping flexibility asset.
