Why should a GRT/TRT be performed?
"Geological risk": Similar to the planning of a building foundation, the exploration and examination of the subsurface has to be included in the preliminary planning stages of medium to large geothermal source systems. Architects, planners and building contractors have to comply with their obligation to communicate information towards the client. In this respect all parties involved in a building process up to the drilling companies can possibly be liable for damages or malfunctions if the client has not been informed unequivocal about necessary preliminary explorations.
Respective guidelines and regulations recommend a response test for geothermal systems with a heating power > 30 kW. Experience shows, that also for smaller geothermal systems, the conduction of a GRT/TRT can pay off.
Generally, safety margins of a conventional system design (based on literature values) can be eliminated after performing and evaluating a GRT. This in turn leads to an optimally dimensioned geothermal source system adapted to the building supply concept, thus saving investment and operating costs. Additionally the GRT allows a hedge of pre-planning design parameters .
The exploratory drilling and implementation of a geothermal response test is demanded increasingly often by approving authorities as part of the water rights application process to identify geological risks beforehand and ensure a sustainable operation of the geothermal system as early as possible in the planning process.