Speaking today about geothermal energy in Croatia, I would dare to say that it will play an important role in the Croatian energy sector because it is recognised as a reliable renewable source of energy.
To date, the Ministry of Economy has issued 8 licenses for the exploitation and 28 licenses for the exploration of geothermal energy for energy purposes, including electricity generation, heating and agriculture. This is the result of numerous activities aimed at the use of geothermal energy in Croatia, which the Croatian Hydrocarbons Agency, together with the Ministry, has carried out intensively over the past five years.
It is the cities and districts that are showing great interest in geothermal projects because they offer them opportunities for a stronger development step. Of the 28 exploration licenses, 13 are owned by companies founded by the municipalities.
The exploration and exploitation of geothermal waters is regulated by the Hydrocarbon Exploration and Exploitation Act. The quality of the legal framework is even recognised at European level and we are an example in Europe as a country that has clearly and transparently regulated procedures. The procedure for issuing permits for exploration and exploitation is a unique procedure and it’s regulated by the Act. The process for obtaining a permit to explore geothermal energy, with the intent to exploit it, is a streamlined one: after fulfilling the obligations of the exploration license, the investor is directly granted an exploitation license.
Based on the Agency’s preliminary geothermal potential assessment, in 2019 numerous locations in the Croatian part of the Pannonian Basin were recognised as potential geothermal exploration areas, and some of them were and are the subject of tenders to select the most favourable bidders. All geological, geophysical and well data needed for the assessment of geothermal potential are owned by the Republic of Croatia and can be accessed (virtually or in person) via the data room organised and managed by the Agency.
After the adoption of Croatia’s energy development strategy in 2020, it became clear that geothermal energy will have it’s role in Croatia’s energy future. Therefore, in 2021, through amendments to the Act, the Agency expanded its role to the preparation and implementation of renewable energy projects, which was an important step in Croatia’s energy transition.
Numerous challenges were identified during the various phases of the development of geothermal projects. The biggest obstacle to the development of geothermal projects is the considerable financial resources required in the initial phase of the projects. The ratio of risk to capital investment is high. This is precisely the reason for the current modest exploitation of geothermal water in Croatia – local governments cannot finance it without partners.
In 2022, the Agency took geothermal projects for district heating from planning to implementation with the help of 55 million euros from the National Recovery and Resiliance plan. The aim of implementing this technically and capital-intensive project is to increase the share of renewable energy sources, more specifically geothermal energy, in the heating sector. Six preliminary exploration areas with existing district heating systems have been identified. The project includes the acquisition of geophysical data, the preparation of geological studies and the drilling of 4 exploratory wells to reduce the initial geological and significant investment risk. Once exploratory drilling is completed, the preliminary areas for geothermal heating will be put out to public tender.
So far, seismic and magnetotelluric data have been recorded and 4 preliminary areas with the greatest potential have been selected for exploratory drilling. A contractor has been selected through the public tender process and preparatory work is currently underway. Drilling and testing is expected to be completed by March 2026, with project completion scheduled for June 2026. The four selected exploration areas are Zaprešić, Velika Gorica, Osijek and Vinkovci. The expected temperatures in geothermal reservoirs range from 60 to 110°C.
Obstacles of a technical nature were also identified, as the planning and development of a geothermal reservoir requires people with specific skills. This was also recognised at the Faculty of mining, geology and petroleum engineering, which is why courses dealing with the exploitation of geothermal reservoirs and the preparation of project documentation for energy facilities were included in the energy study program.
The increasing interest of potential investors in the use of geothermal energy for greenhouse production makes it necessary to find a way to simplify the administrative procedures for carrying out exploration and development activities for the use of geothermal energy for agricultural purposes.
The Agency has launched a number of additional activities aimed at realising as many geothermal projects as possible. For example, the database for deep geothermal energy was created, a workshop for investors was organised to familiarise them with the rights and obligations under the Act, cooperation was established with the Energy Efficiency Fund to promote the use of geothermal energy and much more.
Croatia is actively developing its geothermal potential, with recent investor activity resulting in one well drilled and four commercial discoveries in 2024.
The Agency is continuing the exploration and expects the first results in a few months.