The Vertical Gas Corridor, which connects Greece with Ukraine, has reached a commercial milestone following annual capacity auctions for the 2026/2027 gas year. Bookings covered more than 45% of the available capacity across the next four gas years. The corridor’s development is linked to the results of these auctions and subsequent reservations.
The latest auction outcomes were the first carried out under a revised commercial framework. The framework introduced lower transmission tariffs and additional discounts across selected sections of the route. Market participants said the changes improved the competitiveness of gas transportation toward Ukraine.
The corridor was assessed as the fourth-most cost-effective import route into the Ukrainian market based on those auction results. Some participants also indicated that further incentives may be needed to stimulate additional demand and secure broader long-term commitments. This assessment was tied to expectations for future booking levels.
DESFA reports strong demand at Sidirokastro interconnection
Greek gas transmission system operator DESFA said the auction outcome supports Greece’s ambition to act as a regional natural gas hub. DESFA also said it aligns with efforts to expand supply roles across Southeast and Eastern Europe. The strongest demand was recorded at the Sidirokastro interconnection point on the Greece-Bulgaria border.
Sidirokastro has been described as a key gateway for northbound gas flows. Approximately 46% of available export capacity for the 2026/2027–2029/2030 gas years was booked there. Around 26% of capacity was reserved for the 2030/2031 gas year.
Market participants also secured long-term transport rights extending into future periods. Reservations reached as far as the 2040/2041 gas year. DESFA linked these bookings to expectations of sustained demand for corridor capacity.
Company bookings and auction volumes at Sidirokastro
Several major Greek energy companies participated in the capacity allocations at Sidirokastro. Atlantic SEE LNG Trade, a joint venture between Aktor Group and DEPA Trade, secured around 13,000 MWh per day, equivalent to approximately 4.7 TWh annually. Metlen booked an additional 20,000 MWh per day.
The total export capacity offered at Sidirokastro reached 100 GWh per day. Auction demand was described as broadly matching market expectations. The distribution of bookings reflected participation by multiple companies in the allocation process.
LNG supply interest and review of long-term rules
The booking activity was linked to interest from Greek energy companies in using LNG supplies from Greece for markets in Southeast Europe, Eastern Europe and Ukraine. The corridor is described as increasingly relevant for European energy security and diversification of gas supply sources. It is also associated with reducing dependence on traditional routes.
