Drilling resumes on 7-km geothermal well in Szaflary, Poland
Drilling rig at the Banska PGP-4 site in Szaflary, Poland (source: Rafal Szkaradzinski:)
Carlo Cariaga
1 Jul 2024
Drilling has resumed for the 7-kilometer geothermal well in Szaflary, Poland after work had to be paused due to slow penetration and wellbore integrity issues.
Drilling of the deepest geothermal well in Poland has just resumed after work was paused for about two months due to issues related to a slow drilling rate and collapse of the wellbore. A series of consultations with experts from the drilling industry resulted in some changes to the drilling equipment and procedure. The plan is now to continue to drill to the target depth of 7 kilometers.
First announced back in 2019, the Banska PGP-4 well in Szaflary aims to be the deepest geothermal well in Poland with a target 7-kilometer depth. The objectives of the project included the collection of data on the subsurface geology of the Podhalanska Basin (or Podhale Basin), as well as tap into a geothermal resource with temperatures exceeding 120 °C.
Earlier this year, the project had announced reaching the 5-kilometer depth mark. The results at that time have been optimistic with two feed zones encountered so far – one at 85 °C at about 3ooo meters, and another at 120 °C at 5000 meters. The expectation remains that a third aquifer will be accessed at 7000 meters with a temperature of 150 °C.
Work had to be stopped at a depth of around 5900 meters because the rate of penetration had become very slow. In the last two weeks before work stoppage, only 5 meters had been drilled. The project had previously been drilling at a rate of 40 to 50 meters per day. The walls of the well had also begun to crumble.
After cementing the collapsed section, further drilling began using a new drill and a modified drilling mud. Engineers are hoping that the the increased pressure on the formation will allow drilling to the target depth. It is not known at this point when drilling will be completed, as the initial plan targeted a completion date of March or April 2024.
Geothermal energy from the well is intended to be used for networked heating in the commune of Szaflary and the city of Nowy Targ. Approximately 10 kilometers of pipeline will have to be laid down to connect the well in Szaflary to the facility of Miejskie Przedsiebiorstwo Energetyki Cieplej (MPEC) and to the residential areas of Nowy Targ.
Source: Zakopane Wyborcza and Bankier
