Croatia registered a new record summer electricity demand peak in August, reinforcing the structural shift of system stress from traditional winter periods towards hot-weather evening hours.
Hourly consumption reached 3,400.5 MWh at 21:00, exceeding the previous summer record of 3,362.8 MWh in 2024 and 3,150.1 MWh last year.
The latest peak also exceeded the most recent winter maximum of 3,264.2 MWh.
Higher cooling demand is part of the change, but tourism is an equally important factor. Electricity consumption moves sharply towards Croatia’s coastal and tourist regions during the summer, with demand in some locations rising to as much as five times winter levels.
National consumption reached 10.632 million MWh in January-July, around 1% higher year on year and 1.9% above the 2024 level.
The relationship between temperature and consumption remains complex. July demand of 1.662 million MWh was around 8% below July 2024 despite severe heat this summer.
Humidity, wind conditions, holidays, the duration of heatwaves and tourism activity can all materially change demand.
More important for the power market is the changing hourly profile.
Croatia’s grid is generally most heavily loaded between 20:00 and 22:00. Midday underlying demand can also be strong, but growing rooftop solar generation increasingly supplies some consumption behind the meter.
That pushes the visible system peak towards the evening, when solar production falls rapidly.
HEP is responding by increasing the role of flexible assets. Hydropower output is already adjusted according to system conditions, while market imports are used when domestic production is insufficient.
Battery storage is planned alongside the recently commissioned 75 MW Korlat solar plant and the planned 45 MW Sukosan project.
Longer-term flexibility options include reservoir and pumped-storage projects such as HES Kosinj and HPP Vinodol.
The summer record therefore represents more than another demand milestone. It points towards a Croatian system increasingly shaped by the solar-to-evening transition and the value of storage, hydro and cross-border power during the evening peak.
