The Czech Republic and its geothermal potential

[24. 1. 2025] A map of the geothermal gradient of Great Britain was recently published by one of our PUSH-IT partners. The area of ​​Cornwall, which is part of the project, is one of the most suitable sites in Britain, with a temperature gradient of 35°C / km, meaning that with each kilometer of depth the temperature of the rock rises by approximately 35°C. In the Czech Republic, the average temperature gradient is around 25°C/km, however, there are also places with a larger gradient here. Therefore, in order to find similar places, a map showing the geothermal potential of the Czech Republic was prepared as part of a three-year project and made available to the general public two years ago via an application on the website of the Czech Geological Survey. You can find the link to the map here.

The map of geothermal potential was created by a team of experts from the Czech Geological Survey, the Institute of Geophysics of the Academy of Sciences of the Czech Republic and the Chamber of Renewable Energy Sources of the Czech Republic based on an extensive analysis of data from more than 350 selected wells. In addition to the potential of using geothermal energy, the map also shows its limitations and conflicts of interest. These include, for example, the existence of line structures, airports, power plants and floodplains, as well as mined areas, karst or protected areas. The representatives of the municipalities thus have the opportunity to assess whether the use of geothermal energy is suitable for their locality.

This is not a single map, but an application containing a set of temperature maps at different depth levels (400 - 5000 m) as well as a heat flux density map of the Czech Republic. As mentioned above, the maps were constructed based on the analysis of more than 350 wells.  These wells were selected through a thorough selection of temperature logs from the databases of the Geofund and the Institute of Geophysics of the Academy of Sciences of the Czech Republic from a total number of almost 1000 wells. As can be seen from the map in the picture, wells are spread unevenly within the Czech Republic and it should be taken into account that this is only a model. However, this model is based on the real geological structure (delineation of sedimentary basins, main rock types) and real values ​​of thermal conductivity of rocks assigned to individual rock types. The map shows the estimated potential at medium and large depths below the earth's surface, and everyone, after entering any address or coordinates within the republic, can create their own virtual well and see the predicted temperatures at depths of 400 to 5000 m.

In Litoměřice, where the RINGEN research center is located and where deep geothermal energy is planned to be used as part of the SYNERGYS project, the temperature at a depth of 1 km is around 37 °C, depending on the application. Considering the average annual temperature on the surface, this corresponds approximately to the average temperature gradient within the Czech Republic.  At a depth of 5 km, a temperature of around 140 °C can be expected. In the Czech Republic, however, you can find places with a larger temperature gradient. For example, in eastern Bohemia in Hradec, or in western Bohemia in Karlovy Vary, one can expect temperatures in the range of 40-45 °C in 1 km and 150 to 170 °C in 5 km.
However, it should be noted that for the success of a project using geothermal energy at medium or great depths, it is not only the temperature of the rock at the location of the future geothermal reservoir that is important, but also the geological structure, types of rocks and their petrophysical properties, the presence of water, etc. The most accurate and comprehensive evaluation of the geothermal potential of the given area is therefore a necessary prerequisite for the actual projection of geothermal resources. If you are interested in more detailed information or cooperation in this area, you can contact the experts of the RINGEN research center.