Quality Requirements of a Thermal Response Test

The ground thermal properties and the heat-transfer efficiency of the borehole heat exchanger (BHE) system are key parameters for designing ground-coupled systems. Proper design of such systems requires good knowledge of these parameters, providing an efficient and economic operation. For this purpose a test procedure known as Thermal Response Test (TRT) was developed in 1996 at the Oklahoma State University (USA) by Austin (1998) and the Technical University Lulea (Sweden) by Gehlin (2002). Within a successful cooperation in the IEA ECES further test rigs were built in The Netherlands, Belgium and Germany and in other countries all over the world.