Europe’s renewable energy expansion is facing a new bottleneck that cannot be solved simply by building more solar panels and wind turbines. Around 120 GW of planned renewable capacity is reportedly constrained by limited grid access, while hybrid projects combining multiple technologies could unlock up to 25 GW of additional capacity without requiring entirely new transmission infrastructure.
The opportunity comes from combining technologies with different production profiles and allowing them to share the same grid connection. Solar, wind and battery storage systems rarely reach maximum output at the same time, creating unused network capacity that can be captured through coordinated operation.
A hybrid project can therefore install generation capacity above the nominal export limit of its grid connection, provided that its control system can reduce output or store excess electricity when combined production exceeds the agreed connection capacity. In this model, the valuable asset is not only the power plant itself, but also the controlled ability to deliver electricity through a constrained network.
Hydropower facilities are among the most attractive locations for hybridisation. Many hydro plants use only part of their available grid connection during daylight hours or periods of low water availability. Adding solar, wind or battery storage behind the same connection can increase annual utilisation without requiring the transmission system operator to allocate a separate export route.
Pumped-storage hydropower provides an additional advantage by absorbing electricity during periods of low prices and returning it during morning and evening demand peaks. This makes it a key flexibility technology for power systems with increasing shares of variable renewable generation.
Southeast Europe is already moving towards this approach. Greece is developing regulatory frameworks for storage projects sharing existing grid connections and is considering faster network access for battery systems. Romania’s renewable connection queue has exceeded 91 GW of approved export capacity, while its advanced battery storage pipeline has surpassed 9 GW.
Montenegro’s EPCG–Masdar partnership includes potential development of solar, wind, pumped-storage, battery and hybrid projects within a portfolio that could reach 2 GW. Serbia’s proposed Đerdap 3 pumped-storage hydropower project is also being positioned as a balancing asset designed to support a larger renewable energy system based on wind and solar generation.
Hybridisation is changing the economics of renewable projects. A solar plant equipped with batteries may lose some midday market revenue but can create additional value through evening electricity sales, balancing services, reduced curtailment and improved delivery profiles under power purchase agreements (PPAs).
Wind and solar technologies can also complement each other across different seasons and hours of the day. Wind should not be viewed simply as another form of solar generation with a different capacity factor. Higher wind production during winter periods and overnight hours can reduce the amount of storage needed to provide a stable electricity supply profile.
However, developing hybrid projects introduces significant engineering and commercial complexity. Shared assets require coordinated power plant controllers, export-limitation systems, dispatch rules, metering arrangements, forecasting models and battery degradation assumptions.
Connection agreements must clearly define whether capacity limits apply to total installed generation capacity or maximum simultaneous electricity export. Financial institutions will also require detailed curtailment assessments showing the difference between network-imposed restrictions and operational optimisation decisions.
As grid capacity becomes increasingly scarce, access to existing infrastructure is creating a new development advantage. Projects with secured connection rights, available substation capacity, suitable land and compatible control systems may become more valuable than new renewable sites with stronger natural resources but uncertain grid access.
The next stage of renewable development in Southeast Europe will therefore depend not only on wind speeds, solar irradiation and available land, but increasingly on substations, SCADA systems, grid connection agreements and the ability to manage electricity flows intelligently.
