Southeast Europe has entered a new phase of nuclear planning, with several major projects moving from long-term concepts toward financing, licensing and investment decisions. Romania is advancing one of Europe’s most developed small modular reactor proposals, Bulgaria is pursuing financing for two AP1000 units at Kozloduy, while Slovenia continues preparations for JEK 2. Together, these projects could significantly reshape regional electricity markets, although their combined investment requirements could reach tens of billions of euros.
Romania’s Nuclearelectrica shareholders approved a conditional final investment decision for the Doicești SMR project in February 2026. The proposal would replace a former 600 MW coal-fired power station with six NuScale modules rated at 77 MW each, providing a total capacity of 462 MW. Project communications estimate that the development could create around 4,000 jobs across development, construction, manufacturing and operations, including approximately 200 permanent positions.
The main uncertainty remains cost and financing. Published estimates have ranged from around €4.9 billion to $6–7 billion. Romania has discussed potential support of up to $3 billion from the US Export-Import Bank and another $1 billion from the US International Development Finance Corporation. However, the final commitments, drawdown conditions and capital structure still need to be resolved. Nuclearelectrica said in May 2026 that work was continuing on financing, licensing, cost optimisation and establishing a commercially viable electricity price. Importantly, moving into the next development phase does not represent an unconditional construction commitment at a fixed cost.
Bulgaria’s proposed Kozloduy Units 7 and 8 would use Westinghouse AP1000 technology and provide approximately 2,300 MW of combined capacity. Citi has been appointed exclusive coordinator and export-credit arranger for the project, describing the mandate as its largest nuclear-financing assignment in Central and Eastern Europe. The overall financing requirement has not been disclosed. Unit 7 is currently targeted for 2033, with Unit 8 expected to follow.
Slovenia’s JEK 2 represents an even larger undertaking relative to the size of its domestic market. Public cost estimates have ranged from approximately €9.6 billion to €15.4 billion, depending on reactor capacity and underlying assumptions. A proposed referendum was cancelled in 2024 amid legal and transparency concerns, but technical and project preparation has continued. Because the existing Krško nuclear plant is jointly owned by Slovenia and Croatia, any expansion or replacement project carries important cross-border commercial and political implications.
The three projects share a common strategic rationale: preserving firm, low-carbon electricity as coal capacity is phased out and solar and wind generation expand. Nuclear power can reduce dependence on gas imports, support industrial electricity demand and provide stable generation that complements variable renewable sources. At the same time, the projects face similar challenges, particularly construction delays, cost overruns and the need for state-backed financing or revenue support.
For Southeast European electricity markets, the central question is whether such projects can be financed through commercial revenues alone. In practice, first-of-a-kind nuclear developments are unlikely to rely entirely on merchant electricity prices. Governments may therefore need to consider contracts for difference, state guarantees, regulated-asset models, export-credit financing or direct public ownership. Each approach allocates risks differently among taxpayers, consumers, developers and lenders.
That makes financial transparency and risk allocation just as important as reactor technology. Governments and investors need clear information on expected electricity prices, construction costs, financing conditions and potential downside exposure before committing billions of euros over several decades.
Southeast Europe is therefore not simply deciding which nuclear technologies to build. It is deciding which financial and construction risks it is prepared to carry for the long term. Doicești could help establish an SMR supply chain in the region, Kozloduy could strengthen Bulgaria’s position as a major source of firm electricity, while JEK 2 could deepen the long-standing Slovenia-Croatia energy partnership.
Ultimately, the projects most likely to succeed will not necessarily be those with the largest capacity targets. Credible financing, disciplined project governance and transparent risk allocation will be the decisive factors in turning Southeast Europe’s renewed nuclear ambitions into operating power plants.
