Croatia's grid operator clears key milestone for €50bn Pantheon AI data centre project

Croatia's transmission system operator HOPS has approved the technical blueprint for connecting the planned Pantheon AI data centre campus to the national electricity grid, clearing a major regulatory hurdle for what developers say will be the country's largest-ever private investment, Pantheon Atlas said in a statement on July 23.

The approval initiates the process of signing a grid connection agreement for the planned 1-gigawatt (GW) artificial intelligence-focused campus in Topusko, 70 km south of Zagreb, moving the project into the final stage of securing its power supply, according to the statement.

The project requires more than €500mn of supporting infrastructure, including 280 km of new transmission lines, a 400-kilovolt substation, fibre-optic links and roads. Pantheon Atlas said the infrastructure would be transferred to the Croatian state after completion, strengthening the national electricity grid and enabling the connection of more than 5 GW of renewable energy capacity currently constrained by network bottlenecks.

"The HOPS approval confirms the technical and regulatory feasibility of supplying electricity to the project at scale," the company said in the statement, adding that construction remains on track to begin in early 2027.

Project director Mario Gudelj said in the statement that the development combined Croatian expertise with US investment and strategic partnerships with engineering group Končar and renewable energy developer Greenvolt.

Pantheon AI was unveiled in April as a planned €50bn investment to build a hyperscale AI data centre and innovation campus in central Croatia. The project is designed to deliver 800 megawatts of usable IT capacity, making it one of Europe's largest AI-focused data centre developments.

Developers say the project will help address Europe's shortage of AI data centre capacity while positioning Croatia as a regional hub for digital infrastructure. The campus is also expected to support the expansion of renewable energy generation by financing upgrades to the country's transmission network.

Pantheon Atlas has said the initial campus investment will total around €12bn, with overall investment exceeding €50bn as technology tenants install computing equipment over time.