Synergy will always use the highest quality material for our geothermal projects
Our supplier of choice is MGS
The use of high quality materials and components is essential to the optimal function and life of the borehole array
The two components having the most effect upon borehole performance are, not surprisingly
The geothermal loop and the grout used
Synergy is one of the few borehole drilling companies to offer the complete headerworks, i.e. trenching / pipework / electrofusion welding / manifolds, as part of our service
Here also, the use of the best quality materials and techniques is essential to the long term reliability of the borehole installation
1) The Geothermal Loop
Synergy uses as standard Thermoloops or Ecoloops supplied by MGS.
Thermo-Loops are manufactured from polyethylene (PE100+) in accordance with BS EN 12201 with a working pressure of 16 bar and a lifetime rating up to 50 years.
Due to its properties of being flexible, corrosion resistant and fusible, polyethylene piping has been the choice of the leading contractors in the geothermal industry. Thermo-Loops are proven to perform well under all temperatures and conditions associated with geothermal loop applications
Thermo-Loops have metre markings to provide a guide during installation and are manufactured in any length to order to suit individual project requirements.
Thermo-Loops quality manufacture means all components are of certified material and the production procedure is rigorously checked and pressure tested. Each Thermo-Loop has a unique serial number and hydraulic pressure test certificate.
Available in 25,32, 40mm pipe diameters and up to 300 metres in length
Ecoloops are essentially the same as the Thermoloops but without the test certificate.
2) The Grout
The choice of the exact grout specification may vary according to the requirements of a specific job or client.
A typical grout as used by Synergy, supplied by MGS, is described below
GSL Connect Choice combined with GSL Thermo 99+ is a unique Bentonite-based two part, field mixed, high to extreme-high solids grouting material that can be mixed to meet a range of thermal conductivities from 1.77 – 2.1 Wm-1K-1. GSLConnectChoice and GSL Thermo 99+ contain no chemical polymers or organic matter.
GSL Connect Choice provides unequalled performance while offering the contractor proven advantages in handling and cleanup. When properly mixed, more than 30 minutes of working time is available before significant hydration occurs. Unlike many other grouting materials, GSL Connect Choice will require less water per delivered litre of yield than other grout, as well as linear shrinkage potential which becomes less and less.
Other grouts with differing thermal conductivities are available from MGS. Synergy will be glad to accomodate any special wishes from the borehole array designer.
A word of warning : some others may not possess the powerful mixing and pumping grout units. They therefore reduce the grout solution, i.e. increase the water component in the grout. This will enable their weaker pump to grout the borehole. This however will produce a poorer performing borehole. This can be measured, and sometimes is, by using a Thermal Response Test (TRT). More poorer boreholes will be needed to meet the design performance.
This has been shown / demonstrated to occur on larger projects where cheaper quotes have been taken.
3) Electrofusion Welded Joints
All our electrofusion components are sourced from MGS
It is essential that all underground pipe joints are made using electrofusion welding techniques. These joints will be buried in the ground, invisible to the user for 20 years or more. They must therefore have the highest integrity. Compression, i.e. mechanical screw/O ring joints must not be used for this purpose.
Marton Geotechnical Services Ltd, Geotechnical Centre, Rougham Industrial Estate, Rougham, Bury St Edmunds, Suffolk IP30 9ND