OMV Aktiengesellschaft (OMV) and Energie Steiermark AG are partnering on the Tiefenkraft joint project to advance deep geothermal energy in Styria, southeast Austria.

In the long term, the project could deliver up to 670 GWh/year of geothermal energy by 2037, equivalent to about 50% of the district heating supply in the greater Graz area.

Between February-April 2026, a seismic survey was carried out along about 900 km of roads used as measurement lines. Currently under evaluation, data from the studywill form the basis for a detailed subsurface model as well as for subsequent phases of the project, OMV said.

Following the successful seismic campaign, Tiefenkraft is progressing to exploration well Petersdorf 2 in St. Marein near Graz, with drilling slated to begin in fourth-quarter 2026.

Preparatory work on the project is slated to start in September 2026, with drilling currently scheduled to begin by yearend, subject to permitting and completion of construction at the drilling site. The drilling and subsequent testing phases will take about 3-4 months and are anticipated to provide further insights into the geothermal potential and geological conditions.

 If the results are positive, the next investment decision will cover the development of a first geothermal doublet — comprising one production and one injection well — along with comprehensive testing. In parallel, two possible additional wells are planned to assess the feasibility of an aquifer thermal energy storage (ATES) system, enabling surplus heat to be stored underground and used seasonally.

During this period, planning and groundwork for a pipeline connection to Graz will also advance. Energie Steiermark is contributing infrastructure, system integration, and heat distribution for the project. In addition to its stake in the joint venture, the company will be primarily responsible for constructing and operating a 20-km water pipeline and overseeing the technical implementation required for the integration of geothermal energy into the regional heat supply.

The operator plans to take final decision on the project's full implementation—including all production and injection wells, construction of the pipeline connection to the district heating network, and installation of surface facilities (e.g., pump station)—after completion of comprehensive testing.

The overall development, from initial surveys to commissioning, will span several years.

First heat delivery could begin as early as 2030.