Wedoany.com Report-Jun 1, Since early April 2025, construction has been underway at the Osijek GT-1 exploratory geothermal well site in Tenja, near Osijek, Croatia. Drilling is scheduled to start between late June and September 2025. This project marks the second geothermal well funded under Croatia’s National Recovery and Resilience Plan, following the Velika Gorica GT-1 well, where drilling began in February 2025 and reached 800 meters by early March, aiming for a target depth of 2,900 meters.

Preparation of drill site of the geothermal exploration well in Osijek, Croatia

The Osijek GT-1 well is designed to reach approximately 2,000 meters, targeting a Neogene reservoir in the Pannonian Basin with expected water temperatures of around 100 °C at 1,900 meters. The initiative seeks to assess the geothermal potential for district heating applications, contributing to sustainable energy solutions in the region. “This project is a key step in harnessing geothermal energy to support local heating needs,” said a representative from the Croatian Hydrocarbon Agency (AZU).

In May 2024, AZU awarded contracts for drilling and well design at four geothermal sites, including Osijek and Velika Gorica, as well as Zaprešic and Vinkovci, to CROSCO, naftni servisi, doo (Crosco). These contracts reflect Croatia’s commitment to expanding geothermal energy exploration to diversify its energy sources and reduce reliance on fossil fuels.

The Osijek GT-1 project aligns with broader efforts to develop renewable energy in Croatia, particularly in the Pannonian Basin, known for its geothermal potential. By focusing on district heating, the initiative aims to provide an environmentally friendly alternative for local communities, enhancing energy efficiency and supporting economic development. The collaboration between AZU and Crosco ensures that the project leverages specialized expertise in drilling and geothermal exploration.

As the Osijek GT-1 well progresses, it will provide valuable data on the region’s geothermal resources, potentially paving the way for further development. The project’s success could strengthen Croatia’s position in sustainable energy, fostering long-term benefits for both the environment and the local economy. With drilling set to commence soon, the initiative represents a significant milestone in Croatia’s renewable energy strategy.