Drilling operations have restarted on the ambitious 7-kilometer geothermal well project in Szaflary, Poland.
The project had been temporarily halted due to technical difficulties, but engineers are confident that they have found solutions to continue drilling towards the target depth.
Previous Setbacks and Solutions
Drilling on Poland’s deepest geothermal well was paused for approximately two months due to a slow drilling rate and wellbore instability. Thorough consultations with industry experts led to modifications in drilling equipment and procedures, paving the way for the resumption of operations.
First announced in 2019, the Banska PGP-4 well in Szaflary aims to become the deepest geothermal well in Poland, reaching a target depth of 7 kilometers.
The project’s objectives encompass collecting valuable data on the subsurface geology of the Podhalanska Basin (or Podhale Basin) and tapping into a geothermal resource with temperatures exceeding 120 °C.
Promising Results at 5 Kilometers
Earlier this year, the project achieved a significant milestone by reaching a depth of 5 kilometers. The results so far have been encouraging, with two feed zones encountered: one at 85 °C at approximately 3,000 meters, and another at 120 °C at 5,000 meters.
Expectations remain high for encountering a third aquifer at 7,000 meters with a temperature of 150 °C.
Addressing Wellbore Integrity Issues
Work had to be suspended at a depth of around 5,900 meters due to a dramatically reduced penetration rate. In the two weeks leading up to the stoppage, only 5 meters were drilled, compared to the previous rate of 40-50 meters per day. Additionally, the wellbore walls began to crumble.
After successfully cementing the collapsed section, drilling resumed using a new drill bit and modified drilling mud. Engineers anticipate that the increased pressure on the formation will enable drilling to continue to the intended depth.
Timeline and Geothermal Energy Utilization
The estimated completion date is currently unknown, as the initial plan aimed for completion in March or April 2024.
Upon completion, the geothermal energy harnessed from this well will be used for district heating in the Szaflary commune and the city of Nowy Targ. Approximately 10 kilometers of pipeline will be laid to connect the well in Szaflary to the Miejskie Przedsiebiorstwo Energetyki Cieplej (MPEC) facility and residential areas in Nowy Targ.