Ember Sees 25 GW of Hybrid Hydro Potential Across Seven EU Countries
Existing hydropower grid connections across seven EU countries could absorb 18% of planned new renewables by 2030 without additional transmission lines.
Twenty-five gigawatts of wind and solar can be added to existing hydropower plants across seven European Union countries, enough to integrate 18% of those nations' planned new renewable capacity by 2030 without additional grid infrastructure, think tank Ember said in a report published Wednesday (2026-07-23).3
The timing speaks to a direct constraint now slowing European renewables development. More than 2,500 GW of renewable, large load and storage projects are stalled in connection queues worldwide due to a shortage of transmission capacity, according to data cited by Ember. The IEA has calculated that annual grid investment must rise by roughly 50% by 2030, from the current $400 billion, to keep pace with projected electricity demand growth through the end of the decade.3
Ember's analysis covers Austria, Bulgaria, France, Italy, Portugal, Romania and Spain. The commercial logic is direct: hydro plants in those countries already hold transmission connections that wind and solar developers would ordinarily queue years to obtain. A co-located wind or solar array sharing an existing hydro interconnection avoids that queue entirely.3
Utilisation figures in the report illustrate the upside. Pairing hydro with wind raises overall capacity utilisation at the site to 36%; adding solar pushes it to 31%. Standalone hydro operates at lower rates, constrained by seasonal inflows and reservoir management requirements.3
But Ember's 25 GW sits inside a much larger problem. A separate Ember study published Wednesday (2026-05-20) warned that more than 120 GW of planned wind and solar projects — roughly half of approximately 240 GW of expected European additions by end-decade — face stranding due to grid constraints across 20 countries, Montel reported. Even full realisation of the hybrid hydro opportunity would cover only a fraction of that exposure.1
Germany illustrates how severely the grid problem can bite individual markets. A study by Enervis for advocacy group Green Planet Energy, published Wednesday (2026-05-27), found that a national plan to decongest power networks could disrupt at least 32 GW of wind and solar projects in development, representing roughly EUR 45 billion in at-risk investment, Montel reported. Germany does not appear in Ember's seven-country hydro list, underscoring that the hybridisation route is unavailable in some of the markets where the grid problem is most acute.2
The viability of individual hybrid projects depends on how national regulators handle shared grid access rights at existing hydro sites — a question with no uniform answer across the seven countries. Ember's report does not specify what fraction of the 25 GW is immediately developable versus contingent on regulatory approvals, new civil works or revised grid operating agreements. That distinction shapes how much of the headline figure ever reaches construction.3
The IEA's $400 billion annual grid investment baseline is a global number; Europe's required share represents a spending commitment that most member states are not currently meeting. Hybridisation at hydro sites eases pressure on the connection queue. It does not replace the underlying infrastructure gap.3
The next concrete signal for developers and grid operators in these seven countries is whether any government moves to formalise a regulatory pathway for hybrid connections before the end of current permitting cycles. Without clear rules on how co-located renewables share an existing hydro interconnection, Ember's 25 GW stays a planning figure — and Europe's stranded-project count keeps climbing.3,1