Impact of Sea-Breeze Regimes on Wind Power Production at the Pecineaga Wind Farm (Romania)

This study investigates the impact of sea-breeze circulations on wind power production at the Pecineaga wind farm owned by Eurowind Energy, located in southeastern Romania near the Black Sea coast. The site consists of eight SG170 turbines (135 m hub height, 6.0 MW), representing the largest installed wind turbines currently operating in Romania. The analysis is based on a 27-year dataset (1999–2025) derived from ERA5-driven WRF simulations at 3 km spatial resolution.

Sea-breeze events were identified using an objective methodology based on the Sea Breeze Index (SBI), combined with multi-parameter filtering applied to hourly data. The approach distinguishes between “pure” sea-breeze cases and “embedded” sea-breeze conditions, where the thermally driven circulation interacts with the background synoptic flow. The detection framework relies on paired land–sea reference points to capture both the initiation of the circulation and the inland propagation of the sea-breeze front toward the wind farm area.

Wind conditions at turbine hub height were derived through vertical extrapolation, supported by lidar observations (15-minute resolution, year 2021) used to constrain boundary-layer characteristics and assess vertical wind structure.

Energy production was computed for the entire period using a turbine-specific power curve, both for all atmospheric conditions and for subsets corresponding to identified sea-breeze regimes. Results show that pure sea-breeze events contribute to annual production, while embedded sea-breeze conditions have a greater influence in overall production. This indicates that, although pure sea-breeze events are relatively infrequent, sea-breeze dynamics play a dominant role in shaping the wind regime relevant for energy generation.

The results further suggest that, when interacting with the background circulation, sea-breeze conditions are associated with enhanced energy production, as they contribute to wind speeds within the most productive operational range of the turbines, along with consistent directional shifts toward marine inflow. These findings highlight the importance of correctly identifying and characterizing sea-breeze regimes in coastal wind resource assessments.

The study demonstrates that sea-breeze processes should not be treated as isolated mesoscale events, but rather as a key component of the dominant wind climate in coastal regions, with direct implications for energy yield estimation and wind power forecasting.