Croatia has reached a major milestone in its energy independence journey. INA, the country’s national oil company, has officially completed the €700 million upgrade of the Rijeka refinery — the largest industrial investment in Croatia’s recent history. The project positions the Balkan nation for greater energy security and a cleaner industrial future amid ongoing European efforts to diversify away from Russian energy sources.
The Rijeka refinery, situated along the Adriatic coast in Croatia’s principal seaport city, has long been a cornerstone of the country’s energy infrastructure. The massive modernization program centered on the installation of a new delayed coking unit — a critical piece of equipment that enables the refinery to process heavier, lower-quality crude oil into higher-value products such as gasoline, diesel, and jet fuel.
The project was not without its challenges. Construction delays and the complexity of integrating new facilities alongside existing operations pushed the timeline back by several months. Hot commissioning of the delayed coker began in early 2026, with full-scale operations achieved by the first quarter. The technical achievement involved coordinating hundreds of engineers and construction workers while maintaining safe output from the existing refining units throughout the process.
For Croatia, the upgrade carries strategic significance well beyond simply improving refining margins. The enhanced capability allows the Rijeka refinery to process a wider variety of crude oil grades, reducing Croatia’s dependence on any single supplier. At a time when Central and Eastern European nations are actively diversifying their energy portfolios, this flexibility is an important asset.
INA has also signaled that the refinery upgrade is a stepping stone toward broader sustainability ambitions. Company officials have pointed to planned investments in green hydrogen production at the Rijeka site, which could eventually help decarbonize both industrial processes and transportation fuels. European Union climate targets are driving refiners across the continent to explore hydrogen, and Croatia is positioning itself to be part of that transition.
The completion of the Rijeka project arrives alongside other Balkan energy infrastructure developments. Earlier this year, Croatia and Bosnia and Herzegovina signed a pipeline agreement aimed at further reducing regional reliance on Russian gas supplies. Together, these initiatives paint a picture of a region actively reshaping its energy landscape — and Croatia’s upgraded refinery is at the center of that transformation.
For the city of Rijeka, the project has provided sustained economic activity through years of construction, and the completed facility promises to secure long-term employment and industrial output. As Croatian energy infrastructure enters a newly modernized era, the Rijeka refinery upgrade will be remembered as the project that set the standard.