Croatia is in the midst of a structural transformation of its energy system. The share of renewable energy is steadily growing, particularly through photovoltaic and wind power projects along the Adriatic coast and inland. At the same time, the transmission network is under increasing strain, as generation and consumption are geographically far apart – while the south often produces excess energy, demand in the north and in industrial areas remains consistently high.
The integration of this volatile generation presents new challenges for the grid. Periods of strong feed-in from renewable sources alternate with times of low production. This dynamic requires flexible solutions that can respond to fluctuations in the short term and contribute to grid stability.
The European power grid operates at a frequency of 50 hertz – it is the common rhythm to which generation and consumption align. When more electricity is generated than consumed, the frequency rises above this value; when more is consumed than generated, it falls below.
Even minimal fluctuations disrupt the grid's balance and must be corrected within seconds. When the frequency remains stable, all components of the energy system – from power plants to networks to consumers – run synchronously and reliably. However, the more generation fluctuates, the greater the effort required to keep this rhythm constant.
Grid stable
Renewable energies do not feed electricity into the grid evenly. Their generation follows natural conditions and is thus subject to strong fluctuations throughout the day and across seasons. Energy demand, on the other hand, is comparatively stable – with recurring peaks at typical consumption times.
This structural imbalance between volatile feed-in and steady consumption is one of the central challenges of modern power systems. Periods of surplus production alternate with times of insufficient generation and require precise, short-term interventions in grid operations.
Only through flexible, intelligently controlled infrastructures can this interplay be efficiently and stably managed in the future.