In Croatia, research into the country’s geothermal potential continues with the start of the Zapresic GT-1 well, located near the Novi Dvori landfill in Zapresic, a town in Zagreb County, the local authority said in an update.
It forms the last of four drill locations as part of a national geothermal potential research project led by Croatian Hydrocarbons Agency (AZU).
AZU said in October that well site preparation was underway for the construction of the fourth and final well site for the drilling rig.
According to the Zapresic statement, previous research has already confirmed positive findings in Velika Gorica, Osijek and Vinkovci.
Zapresic is the next step in determining whether commercial geothermal deposits exist that are suitable for district heating needs, it noted.
"We have conducted detailed measurements and analyses at locations with geothermal potential, which have given us a good initial picture, but we can only obtain reliable data by going deeper,” said Martina Tuschl, Director of the Geothermal Energy Sector at AZU.
“The expertise of our team has been confirmed at the previous three locations where the wells have yielded positive results, and we are applying the same approach in Zapresic. Upon completion of the testing, we will have clear information about the actual geothermal potential of this area.”
She also explained that the targeted deposit is located at a depth of about 2,700 metres, where the temperature and flow of geothermal water will be measured, key parameters for assessing the deposit's economic viability.
The work at Zapresic is expected to continue until February 2026.
“This is an important moment for Zapresic,” according to the city’s Mayor Zeljko Turk.
“A project has begun that opens up the possibility of using our own source of clean energy and creating a modern, safe heating system. We believe in a positive outcome and look forward to the results that will show that our city can make a step forward towards a sustainable and long-term profitable solution for citizens, as well as the economy.”
Potential future uses of the geothermal energy in the area include the Falecnjak enterprise zone and a new planned city swimming pool.