Week 23 wind drop and impact on variable renewables
In Week 23, wind generation across Southeast Europe fell 15.5% week on week, contributing to most of the decline in variable renewable output across the region. The weaker wind conditions also coincided with stronger reactions from electricity prices, balancing requirements and thermal dispatch across multiple markets.
The largest renewable-output declines were recorded in Romania, Croatia and Serbia, attributed largely to weaker wind generation. Greece also saw a clear drop, with wind output down 16.5%, which more than offset a modest 1.8% rise in solar generation.
The different operating characteristics of wind and solar were highlighted by the same week’s results. Wind has a different hourly pattern and seasonal profile than solar, and it can support evening and night-time supply when available. When wind output falls, system replacement can come from hydro, imports, lignite or gas.
Separate modelling for wind project finance
Project finance approaches for wind in Southeast Europe need to treat wind separately from solar. Wind can deliver higher capacity factors and stronger system value during non-solar hours, while its week-to-week volatility increases exposure to imbalance costs.
Lenders and investors are advised not to rely only on annual P50 generation figures. Instead, they need P90 downside cases, imbalance-cost assumptions, curtailment sensitivity, capture-price modelling and realistic exposure to balancing markets.
System-wide demand, thermal dispatch and imports
The regional system effect was visible alongside the renewable decline. Regional demand rose 8.2% to 15.15 TWh, while variable renewable output fell 8.9%.
Thermal generation increased by 24.5% to 4.22 TWh, reflecting the need for dispatchable supply when wind weakened. Net imports rose by 9.1% to 1.22 TWh, aligning with the shift away from variable renewables during the week.
Bankability factors for wind developers in regional markets
The implications for developers extend beyond technical performance into commercial structures. For wind projects in Serbia, Romania, Croatia, Greece and Bulgaria, managing volatility is described as central to bankability.
The source conditions indicate that projects may remain attractive where production occurs outside solar-heavy hours. Forecasting improvements, portfolio aggregation, hybridisation with batteries, flexible PPAs and access to balancing services are listed as factors that can influence project returns.
Curtailment and grid constraints at constrained nodes
The financing considerations also intersect with grid limitations in markets under pressure from new renewable connections. A wind farm sited in a constrained node may face both imbalance risk and curtailment risk.
A project with strong wind resources but weak grid access can see revenue quality deteriorate quickly when constraints bind . This makes the interaction between resource performance and network conditions part of the risk picture for new builds .
