Expansion of Agh Ust Laboratory For Geoenergetics and Borehole Heat Exchangers Drilling Process Optimization

Laboratory for Geoenergetics has been founded on AGH UST under the Faculty of Drilling, Oil and Gas in 2008. At that time 5 borehole heat exchangers (A field) have been installed with their construction varying between them. The system consists of one coaxial, one double U-pipe and three single U-pipe BHEs. The cement slurry used in each borehole also varies. In 2017 additional 14 boreholes (B field) have been drilled, which have been used to heat the D-2 building on the AGH UST campus. The Laboratory has continuously progressed and expanded since its beginnings. As of now there are works set to construct 4 new boreholes of which 2 will be used for BHEs coupled with a direct exchange geothermal heat pump, and the other 2 meant to be borehole-based energy storage systems (gravity and pressure storage). Additional systems will include 2 HDD heat exchangers and a geothermal doublet, which will further expand the B field of the Laboratory. All previously described works will be completed next to the A-4, D-2 and C-6 buildings on the AGH UST campus. Another project is the construction of C field in Młoszowa, which will comprise of 18 BHEs that will supply the Manor and Park Complex with heat. They will be used to improve our understanding of such installations and to test a new construction of BHE pipes in boreholes. The drilling process will be completed using a DTH Hammer drill. During the drilling process several parameters connected to energy consumption will be monitored and recorded, including compressed air pressure, pure drilling time, drilling speed, drilling string pressure, drill wear and energy consumption. Those and other actions will be conducted at the same time with the aim being to gather enough data for optimization of the whole DTH Hammer drilling process. The study will include live monitoring of whether the actual works match with the previously planned schedule. After the first 9 boreholes are drilled a statistical model constructed on the data will give us information about which pressure and speed generate the lowest costs. Provided the system has been properly calibrated and the measurements taken accurately such undertakings might prove themselves particularly effective when the number of boreholes drilled in the same location reaches tens of boreholes, or even hundreds.