Research and Teaching Capacities of the Geoenergetics Laboratory at Drilling, Oil and Gas Faculty AGH University of Science and Technology in Kraków (Poland)

The dynamic development of renewable energy recovery systems and also rationalization of heat management gave spur to the construction of the Geoenergetics Laboratory at Drilling, Oil and Gas Faculty AGH University of Science and Technology (DOGF AGH-UST) in Krakow. One of the important factors deciding about the build are previous works on adapting depleted and negative wells. Research carried out at the Laboratory up today and its usability functions are described in the paper. The laboratory is based on various types of borehole heat exchangers. They were investigated in view of their design for their effective thermal conductivity eff and thermal resistance Rb. The thermal response tests were used for elaborating BHE thermal conductivity test. It can be used for optimizing the structure and technology of exploitation of large underground heat storages with borehole heat exchangers. This system can co-operate with various types of solar collectors which in an appropriate climate zone may be a perfect source to be used for charging underground heat storage. 1. INTRODUCTION At the end of 1990's the idea of borehole heat exchangers (BHE) started to be in focus at the Faculty of Drilling, Oil and Gas AGHUST, coinciding with the opening of a PhD procedure on the application of existing, old boreholes for heat recovery from the rock mass (Sliwa 2002). The first works on underground heat stores were realized in 2006. As the use of the rock mass for heating/cooling purposes covers many disciplines, a dedicated laboratory was worked out, where BHE design, performance and exploitation, underground heat storages performance and modelling, as well as renewal of energy resources in underground storages could be analyzed. Rock mass can be a source of heat and cold energy for heating and heating/cooling installations making use of heat pumps. This type of installations is more frequently realized in developed countries. Such systems rely not so much on recovering renewable heat, as on rational managing of heat in objects. It lies in using heat of the rock for heating in the heating season, and making use of cold of the rock to air-condition the interior space of buildings. Air conditioning is a reverse process to heating. Having borehole heat exchangers, one may cyclically use the rock mass as a source of heat or cold. Instead of going up to the atmosphere, energy flows are circulated between the receiver (building) and the rock mass. This process can be passive to some extent, i.e. without heat pumps, which adjust energy (temperature) to the reception conditions. As far as environmental protection and energy aspects are concerned, the driver-energy of heat pumps is very important. In the Polish conditions, electrical energy mainly comes from coal combustion. The thermal capacity of heat pump as referred to the primary energy of coal is slightly above 100 %. Heat pumps substitute electrical energy heating, hence are favorable energetically and ecologically. If a local, traditional source of heat (coal, gas, oil) is replaced with a heat pump, the energy and environmental effect will be less distinct. In the case of electrical energy production from renewable sources, e.g. in Scandinavia, the use of heat pumps is unquestionably purposeful. To enable designing and exploiting borehole heat exchangers, a specialist Laboratory of Geoenergetics was established at the Faculty of Drilling, Oil and Gas AGH-UST. It is part of Interfaculty Field Station for Environmental Surveys. The Laboratory's works were inaugurated in 2007, when the first in Poland commercial Thermal Response Test (TRT) was performed (Gonet and Sliwa 2008).