September 30, 2024, Schwanau Germany. Drilling work for Bavaria's 25th deep geothermal project in Polling (district of Mühldorf am Inn) started in spring 2024 and reached the reservoir with hot water at a depth of around 2,600 meters at the beginning of September. The volume and temperature of the deep groundwater, which is returned to the underground reservoir in the production cycle, are in line with expectations. The water extracted from the ground at a temperature of over 100 degrees Celsius can be used to generate district heating in a geothermal plant with a thermal output of around 30 MW.

The district heating is used to heat the greenhouses of the regional vegetable and fruit grower Reichenspurner Hof, which has a production area of over 360,000 m², and the municipality of Polling. In addition, some of the sustainably generated energy will also be used to supply the planned district heating networks in Mühldorf am Inn and Tüßling. The initiator of the geothermal project is Erdwärme Inn GmbH & Co. KG, while Geoenergie Bayern Beteiligungen GmbH is responsible for project development. H. Anger's Söhne – Bohr- und Brunnenbaugesellschaft mbH was the company responsible for the deep drilling. RED Energy Drilling was responsible for the geological and geohydrological work, while KEMCO GmbH was responsible for the drilling planning and project management.

Small footprint, highly automated and low noise emissions
When geothermal energy is used to generate heat, cooling and electricity using hot water from the depths, the transport routes and especially the pipes needed for district heating must be as short as possible. For reasons of efficiency, both the drilling site and the geothermal plant should be located near built-up areas, whose buildings can then be heated with the generated heat. Herrenknecht deep drilling rigs set standards in terms of structural flexibility and environmental protection. With their electro-hydraulic drive and automated handling of the drill pipes, they are considered the quietest deep drilling rigs on the market.

Machine control with artificial intelligence
Herrenknecht is further expanding this lead in a research project with the University of Applied Sciences in Offenburg. Machine data and noise generation are analyzed using artificial intelligence methods and used to control the deep drilling rig. This minimizes noise on the construction site while ensuring that the drilling is carried out in the most technically efficient way and in the shortest possible time.

Many years of experience
Herrenknecht Vertical deep drilling rigs have been used in a third of all geothermal projects realized in Germany. In Upper Bavaria, which is particularly suitable for deep geothermal energy, Herrenknecht deep drilling rigs have already been used in the current project in Polling as well as in projects in Halsbach, Dürrnhaar, Kirchweidach, Traunreut and Freiham. Herrenknecht Vertical has been producing deep drilling rigs at the headquarters of the Herrenknecht Group in Schwanau, Baden, since 2005 and sells them worldwide.
 

DATA GEOTHERMAL PROJECT IN POLLING

• Client: Erdwärme INN GmbH & Co. KG
• Contractors: H. Anger's Söhne – Bohr- und Brunnenbaugesellschaft mbH
• Application: deep geothermal energy
• Drive lengths: 1x 3,700 m & 1x 4,200 m
• Geology: Malm (limestone, dolomite)
   

BORING TECHNOLOGY

• Machine type:  Innova Rig (TI-418)
• Height: 51.8 m
• Power rotary head: 3,500 kN
• Drive power: 4,000 kW
• Hoist power: max. 2,000 kW