Romania is preparing one of Southeast Europe’s most important nuclear investments: the refurbishment of Unit 1 at the Cernavodă nuclear power plant. In July 2026, the European Investment Bank approved an €800 million loan for the project, placing public finance behind the effort to keep the reactor operating for another 30 years.
Unit 1 entered commercial operation in 1996 and normally supplies about 10% of Romania’s electricity. Extending its life preserves a large block of low-carbon, dispatchable generation at a time when coal is scheduled for retirement and renewable production is becoming more variable. It also maintains skills and supply chains associated with Romania’s CANDU reactor fleet.
The EIB loan is financing, not the complete project cost. Refurbishment involves replacing or upgrading major reactor systems, undertaking extensive safety work and preparing the unit for a second operating cycle. It is a complex outage project whose cost and timetable must be managed as carefully as those of a new plant, although it generally avoids the greater risk of constructing an entirely new nuclear site.
The strategic case is strong. Romania’s two Cernavodă units normally account for around one-fifth of national electricity output. Their stable generation complements wind and solar and reduces exposure to imported fossil fuels. Nuclear life extension can therefore provide decarbonisation and security benefits without waiting for an unproven new reactor programme.
The August 2026 Danube emergency nevertheless exposed an important limitation. Record-low water forced one reactor offline and threatened the remaining unit’s cooling supply. Authorities removed a rock obstruction, dredged the riverbed and created a temporary dike from rock-filled barges, increasing the local water level by about four centimetres and extending operation by at least nine days.
This episode changes the meaning of nuclear resilience. Fuel security and reactor safety remain fundamental, but future investment must also address heat and water stress. Cooling-system design, intake infrastructure, river-basin forecasts and operating limits need to reflect more extreme climate conditions. A plant may be low-carbon while still being climate-exposed.
The regional implications are immediate. A Cernavodă outage tightens supply not just in Romania but across interconnected SEE markets, especially when hydropower is simultaneously constrained by drought. That correlation strengthens the case for batteries, demand response and interconnectors alongside nuclear refurbishment. Firm generation is valuable, but no single asset is fully firm under every climate scenario.
For other SEE nuclear states, Romania’s project provides a useful benchmark. Bulgaria, Slovenia and Croatia all face decisions about extending existing plants or constructing replacements. Refurbishment can be faster and less capital-intensive than new build, but only if regulators confirm safety and climate-related vulnerabilities are addressed.
Cernavodă Unit 1 is thus more than an ageing reactor receiving new equipment. It is a test of whether SEE can preserve its existing low-carbon base while adapting it to a harsher operating environment. The €800 million EIB commitment signals confidence in the project; the Danube crisis defines the resilience standard it now has to meet.
