New grid connections are becoming harder to secure. At the same time, electricity demand rises, putting pressure on the precious metal extraction and supply. This increases the importance of better utilizing allocated grid capacity and existing in-plant electrical infrastructure. One practical solution is to hybridize operating wind farms (WFs) with solar photovoltaic (PV) systems by connecting directly to the existing internal medium-voltage (MV) cable network, thereby avoiding the need for new MV cables and a new grid connection.

This paper presents a methodology for estimating the amount of PV capacity that can be integrated into an existing WF without reinforcing the internal cable network. The approach is based on three main principles: the temporal complementarity between wind and solar generation, operational curtailment strategies, and the possibility of allowing short-term cable overloading by accounting for cable thermal inertia.

The framework is demonstrated on a 22.5 MW onshore WF in Denmark with a radial collection network. Results show that, under conservative assumptions, approximately 25% of installed capacity can be added as a PV system while respecting needed cable constraints. Allowing limited cyclic overloading can increase the admissible PV capacity by up to a factor of two for certain cables, while overloading events remain rare and short. Across all evaluated cases, hybridization improves the grid utilization factor by up to 31%.

Overall, the results show that coordinated wind–solar operation and flexible cable utilization can support more efficient use of existing infrastructure and facilitate the integration of renewable energy in grid-congested areas.