Results

The project has generated four major outputs. 

• Report on priority applications, market scale and socio-economic impacts
• Report on the prototype pile design and its performance under test
• Report on the pile FEM analysis with recommendations for optimal performance
• Value proposition and commercialisation plan

These reports are confidential to the consortium but a summary of the results achieved can be publicly shared.

Technical Performance:

Hydraulic and thermal analysis codes have been used to analyse how the ground heat exchanger functions.  The pile geometry has been optimised to give maximum thermal coupling with the ground whilst also maintaining a turbulent flow within the pile to maximise heat transfer from the fluid.

Detailing of the pile was also analysed using thermal finite element analysis.  This confirmed that a simple 2D model of the pile would give good accuracy.

Characteristics of the ground have a major impact on the thermal performance of the pile.  Moisture within the soil assists thermal conduction away from the pile.  Using screw pile technology to insert the pile to a depth of up to 12m will be an important advantage, to reach depths where water is present.

In most ground conditions, the thermal performance of the pile is shown to be effective as a means of producing chilled water.

Performance Validation

The results from the modelling work have been validated by means of an experimental test rig.  This comprises a length of pile installed into the ground at the testing site of ABC Anchors.  A thermal flow and monitoring system was built to measure performance of the test pile.  This testing confirmed that the modelling work was broadly valid.