When the 13 EU member states of the Three Seas Initiative (3SI), their strategic partners and associate countries, gathered in Dubrovnik in April to mark the grouping’s tenth anniversary, they had reason to be proud of what they had built. The 3SI group of countries stretch between the Adriatic, Baltic and Black Seas and come together to improve north–south connectivity in energy, transport and digital infrastructure. Since 2016, they have helped build the infrastructure that enabled the EU to diversify away from Russian gas. The bloc has reduced pipeline imports from Russia from almost 160bn cubic metres (bcm) in 2021 to less than 40bcm in 2025.
However, gas offers only a partial solution to the EU’s energy security problem. The bloc has largely replaced Russian pipeline supplies with liquefied natural gas (LNG) from America and the Gulf Arab states. This shifts geopolitical exposure without ending fossil-fuel dependence. Besides, infrastructure commissioned today typically has an economic lifespan of around 20-30 years—meaning it risks outlasting the EU’s legally binding goal of climate neutrality by 2050.
The 3SI now needs to focus more on developing renewables. Its new “fund of funds”, which offers at least €2bn for regional infrastructure, is the mechanism to make that shift.
Gas lock
Up to now, the 3SI has focused on gas investments, partly because of the need to diversify away from Russian dependence. This included Romania’s Neptun Deep field (a Black Sea deepwater project set to begin production in 2027, making Romania the EU’s largest gas producer), infrastructure funding that included capacity expansions at Greek, Polish and Croatian LNG terminals, and improved regional interconnections. Of the 59 energy projects the 3SI has undertaken, gas has consistently been the priority; the six projects that have been completed since 2021 were all gas-related. That infrastructure will earn its keep: gas will remain a primary energy source for at least a decade, given that 3SI states still rely on fossil fuels for more than half their energy needs.
However, even though Russia accounted for under 12% of EU gas imports in 2025, the 3SI’s focus is still mostly on gas. The most recent 3SI investment catalogue from the Dubrovnik conference confirms this. Gas infrastructure and diversification corridors dominate the energy portfolio; five out of nine “flagship” energy projects are related to gas. Clean energy initiatives—hydrogen, storage, grid interconnections—feature in the catalogue but are treated as supplements to a gas-first strategy rather than the foundation of a new one.
Renewable promise
The 3SI countries have significant potential for developing renewable energy sources, biogas, nuclear energy, energy storage and hydrogen technologies. These could form the foundation of the region’s long-term energy security. All the group’s members aim to increase the share of clean energy, including renewable sources, in their electricity generation. Baltic states, for example, have set an offshore capacity target of 26.7 gigawatts by 2030; the total potential for energy generation in the Baltic Sea is estimated at around 93 gigawatts, against less than 5 gigawatts installed today.
Other members are also developing nuclear capacity: Poland is building its first large plant (first reactor expected online in 2036) alongside small modular reactors; the Czech Republic, Slovakia and Romania are planning new units. Joint investments in transmission networks, offshore projects, smart energy systems, and research and development projects could strengthen the competitiveness of the economies of central and southern Europe.
A cleaner agenda
The 3SI member governments should build a clean energy agenda alongside their gas investments. This should include joint investments in hydrogen production and cross-border infrastructure, large-scale renewable energy projects, and the accelerated expansion and modernisation of electricity grids. A better balance between gas and clean energy investments will be important for the region’s future role in European energy policy and could become a core pillar of deeper regional integration and industrial development.
The fund of funds, established at the last Three Seas summit, is the right vehicle to do so. It aims to unlock at least €2bn for infrastructure projects across central and eastern Europe and is designed to crowd in private capital—the headline figure should seed investment that unlocks multiples of that amount in total project finance.The fund amounts to a considerable sum, especially given that the cost of implementing the most important gas projects by the Three Seas countries between 2016 and 2025 was just over €4bn. Its value is also twice that of the initiative’s previous fund, which wound up in January 2026 at just under €1bn.
The fund should direct its resources toward renewables, storage, hydrogen, grid modernisation and cross-border interconnections. That ambition needs to be embedded in the fund’s investment mandate: member states should agree minimum clean-energy allocations and exclude new unabated gas capacity from eligibility. Directed toward clean energy, the fund would strengthen regional energy security, reduce fossil-fuel dependence and mobilise private capital for low-carbon investment.
The 3SI has proved it can build energy infrastructure at scale. The question now is whether it will build the right kind. With the fund of funds in place, 3SI members now need the will to direct investments toward clean energy rather than more gas.
About the author
Szymon Kardaś is a senior policy fellow on energy within the European Power programme, based in ECFR’s Warsaw Office.