Three ±525 kV HVDC links under the Black Sea

The corridor consists of three independent voltage-source converter (VSC) HVDC links operating at ±525 kV, each rated at 1,300 MW, giving 3,900 MW of transfer capacity at full build-out.

Overhead and underground lines cross Azerbaijan and Georgia to the coast at Anaklia and Poti. Converter stations at Ksani and Tskaltubo connect the corridor to the Georgian grid in both directions, so Georgia can export its renewable surplus and import when it needs to.

From the Georgian coast, submarine cables of about 1,120 km each cross the Black Sea, mostly over the abyssal plain at depths of up to about 2,200 metres, to the Constanța Sud landfall in Romania. In Romania and Hungary the corridor connects to the EU grid at Constanța Sud, Domnești (Bucharest) and, through an onshore extension to Hungary, at the Albertirsa substation near Budapest.

A Feasibility Study by CESI, covering resources, demand, technology, routing, grid integration and the business model, was approved at the 12th Ministerial Meeting of the Parties in Baku on 8 July 2026. The project is now in its development phase, preparing tenders and the roadmap to the final investment decision.

Assessed in full, kept as a long-term option

The Feasibility Study assessed green hydrogen alongside electricity: demand in the four countries, production, storage and transport technologies, and a dedicated hydrogen pipeline from Azerbaijan to Hungary. Under the reference assumptions, the HVDC electricity links clearly outperform hydrogen transport over the 2030–2040 horizon, and no hydrogen pipeline proved economically viable within that period. Hydrogen therefore stays out of the current development phase but remains a long-term option for the corridor.

Hydrogen demand and production

• Domestic green hydrogen demand in the four countries (reference scenario): about 440 kt in 2032, rising to about 875 kt in 2040. The 2040 split is Romania 471 kt, Hungary 269 kt, Azerbaijan 85 kt and Georgia 49 kt.
• Electrolyser capacity in the modelled pathway: about 2.7 GW in 2032, rising to about 7.6 GW in 2040. The 2040 split is Hungary 5.5 GW, Azerbaijan 1.0 GW, Georgia 0.6 GW and Romania 0.5 GW. All of it serves domestic demand.
• Azerbaijan's wind resource is very strong. The levelised cost of green hydrogen from a wind and solar mix is estimated at about €2.9/kg in 2030, against about €3.7/kg for green hydrogen produced in Europe (EBRD).

Candidate hydrogen pipeline

• Route: Baku – Georgia – Black Sea – Romania – Albertirsa (HU), about 3,000 km in total (about 1,900 km onshore and about 1,115 km offshore across the Black Sea), aligned with the HVDC corridor where possible to share permitting and construction.
• Five sizes were assessed, from 16″ to 36″ in diameter, carrying 100–950 kt of hydrogen a year (about 3.3–31.7 TWh).
• Preliminary investment: €6.6–13.0 billion, depending on size.

Why electricity first

• Expected EU hydrogen imports before 2040 have been revised sharply downward since the REPowerEU targets were set, so early export volumes would be modest.
• After stakeholder workshops, the participating countries adopted a "Late Adoption" hydrogen pathway as the reference scenario.
• On that basis, the electricity links deliver about 20 TWh a year to Europe by 2040, while a pipeline would carry far less than its capacity.

Why hydrogen stays on the agenda

• Each GEC link adds renewable capacity in Azerbaijan and Georgia, and that capacity can also supply electrolysers.
• Pipelines are the most cost-effective way to move hydrogen over distances of up to about 3,000 km, which fits this corridor.
• Under a high-production scenario, Azerbaijan could supply 10–15% of the EU's hydrogen import needs by 2040.

GECO will review the hydrogen option as the European hydrogen market develops.