IN Brief:
- Opor operates six 4.5 MW Nordex turbines and Boraja II operates ten, for 72 MW combined.
- The two Croatian wind farms have entered commercial service under 12-year contracts for difference.
- Acciona forecasts 203 GWh of combined annual generation and now has 102 MW of operational Croatian wind capacity.
Acciona Energía has completed commissioning at two Croatian onshore wind farms and brought their combined 72 MW into commercial operation. The Opor installation contributes 27 MW and Boraja II adds 45 MW, with both now supplying electricity to the national system. Each project has a 12-year contract for difference awarded through Croatia’s renewable support programme, tying the new operational capacity to an established electricity-market settlement mechanism.
Opor lies in Split-Dalmatia and operates six Nordex turbines, while Boraja II in Šibenik-Knin has ten. Each machine carries a 4.5 MW electrical rating on a 105-metre steel tower, giving the wind farms capacities of 27 MW and 45 MW respectively. The towers transfer rotor and nacelle loads to their foundations and place the machines above ground-level wind obstructions. With the two sites now operating, their separate turbine groups contribute to the total through their own collection networks and grid connections.
The project’s physical delivery now gives way to normal operational control, with turbines, collection circuits and protection equipment working together to supply the grid. Before commercial acceptance, plant operators test equipment and communications, the response of electrical protection, and the coordinated behaviour of individual turbines under the applicable grid requirements. Acciona’s confirmation that both sites are supplying electricity establishes a different milestone from a turbine installation or a project merely entering construction.
Acciona projects combined output of approximately 203 GWh in a typical year. At 72 MW, the sites’ combined theoretical maximum over 8,760 hours would be about 631 GWh, and the forecast corresponds to an indicative capacity factor of roughly 32%. Actual generation will reflect the wind resource, turbine power curves, electrical losses, availability and any restrictions on export. The annual estimate provides a planning benchmark against which metered performance can be assessed once a full operating year has elapsed.
Acciona also estimates annual avoided emissions of around 135,000 tonnes of carbon dioxide, calculated against an assumed alternative generation mix. The figure is separate from electricity production and will vary with the generation displaced on the system. Construction supported up to 400 direct jobs at peak activity, according to the company; routine operation requires ongoing turbine, electrical, civil and safety maintenance. The 400-job estimate describes peak construction employment rather than a stated permanent operating workforce.
At each park, the electrical collection network gathers output from turbines operating at continually changing rotor speeds. Converter controls manage electrical output to meet connection requirements, while transformers provide the voltage changes needed for transmission to the grid interface. Switchgear and protective relays isolate faulted equipment and allow healthy circuits to remain available where system design permits. These functions become part of routine operation alongside mechanical maintenance, because electrical availability can affect the export of electricity even when wind conditions would support generation.
The revenue arrangements are 12-year contracts for difference awarded through a public auction under a Croatian government support scheme involving market operator HROTE and approved by the European Commission. Under this type of structure, qualifying electricity receives a reference-price treatment that reduces exposure to movements in the wholesale market, subject to the applicable settlement rules. Generation volumes still determine the energy eligible for settlement, and the contracts do not eliminate the operational variability intrinsic to wind production.
Operating maintenance will now centre on turbine inspection, blade condition, drivetrain and control-system diagnostics, and the electrical assets that collect and export power. SCADA monitoring can identify changes in component performance and availability, while planned shutdowns allow inspections or replacements that cannot be performed during generation. Grid operators may also require reactive-power support or controlled changes in active output, making site control systems central to the parks’ continuing compliance with their connection agreements.
Acciona already operated the 30 MW Jelinak wind farm in Split-Dalmatia, which entered service in 2013. Adding the two new parks lifts its Croatian operational wind capacity to 102 MW. Separately, the company is constructing the 189 MWp Promina solar development in the Šibenik-Knin region. That solar capacity is a planned photovoltaic peak rating rather than additional wind generation already commissioned. The figures show two different project stages within the company’s Croatian portfolio.
The commissioning of Opor and Boraja II increases Acciona’s Croatian wind operating portfolio from 30 MW to 102 MW, alongside its existing Jelinak plant. Promina, its separate 189 MWp solar project in Šibenik-Knin, remains in construction. The newly operating wind farms have defined generation ratings and contracts for difference; their reported 203 GWh combined annual production and avoided-emissions estimates will be assessed against metered output over time.
