Thermal Response Testing saves time and money

The use of residential "rule of thumb" sizing guidelines has resulted in  commercial systems that are oversized and therefore not as cost effective as they could be.

GeothermalPlus, in association with Drilcorp and Northumbria University* recently finished the design and construction of a new Thermal Response Testing (TRT) rig. The facility, designed by Professor Chris Underwood at Northumbria’s School of the Built Environment, will aid the investigation and more efficient design of closed loop ground energy systems. The unique self contained, towable unit has its own micro Combined Heat and Power (CHP) module making it fully independent and useable virtually anywhere.

Thermal response tests are used to provide in-situ measurement of the thermal properties of the local geology and play an important part in developing cost-effective and sustainable designs for closed loop ground energy systems. 

Initial borefield designs for a ground source heat pump (GSHP) system are usually based on available data or “rules of thumb.” This will give enough data for an approximation of how the system will perform in local ground conditions. This approach can result in too many boreholes being specified, significantly increasing costs as drilling is the most expensive element for a closed loop GSHP system, or too few being drilled resulting in an under sized, inefficient system.

Thermal response testing is generally only required for projects where over 10 to 15 closed loop boreholes are required for heating and/or cooling.  GeothermalPlus and Drilcorp engineers will drill and operate the rig, and, as analysis and design is undertaken by GeothermalPlus, you will only ever be dealing with one company.

A test borehole would be drilled and our rig attached to the loops in the ground. This borehole would be would be designed to be included as a part of the final borefield, reducing costs. The CHP powered instruments in the rig allow data to be recorded throughout the duration of the test, providing records of the flow and return temperatures. It is these that allow the calculation of the necessary parameters for the optimal design.