Geothermal Borehole Drilling: How Does A Ground Source Heat Pump (GSHP) Work?

by | Aug 28, 2020

Increasingly, homeowners look to their own back gardens to heat their homes. How? Through the use of ground source heat pumps (GSHPs). These simple, yet deceptively clever pieces of kit help leave your home toasty and warm. Even in the harshest of winters. Asides from requiring a certain amount of outside space in which to install the pump, this easy-to-install equipment is a great investment. The team here at Borehole Solutions, wanted to look at how exactly a GSHP works, in practice.

How Do They Work?

Once the decision has been made to install a GSHP, a geothermal borehole drilling contractor (or other geotechnical contractor) is contacted. They will then carry out the installation process. Having drilled boreholes or excavated the ground, loops of piping are installed. Through this refrigerant/heat-carrying fluid is pumped  circulated, transferring absorbed heat from the ground back up to the surface, to the property.

Typically, the refrigerant used within GSHPs is R410-A, is commonly used in air conditioning units and refrigerators. The number of boreholes that are drilled (or the length of trenching dug out) depends on the size of the property requiring heating. As well as the property’s underlying geology – as some rocks and soils transfer heat better than others.

Vertical Or Horizontal?

Whether the pumps are installed in horizontal pits or vertical-based boreholes depends on the amount of space available at a property. Where space is limited, vertical systems will be implemented. For vertical systems, where geothermal borehole drilling is required, boreholes of up to 100 metres in depth will be drilled. With the piping then being installed. For horizontal systems, a trench of only a couple metres in depth is excavated (so that the installed piping is below the frost line) with piping of up to almost 200 metres in length being laid out.

The Benefits

Running considerably cheaper than oil boilers, these heating systems are consistent and reliable. Not to mention relatively inexpensive to install. Combining this with the additional Government incentives (which we’ll come onto), the decision becomes a no-brainer. The only downside is that this option is only available to those with the requisite outdoor space. To find out more about the benefits of these heat pumps, read our previous blog on the subject here!

Domestic Renewable Heat Incentive (RHI)

If the thought of easy, clean energy isn’t enough of an incentive, then consider the benefits that the Domestic RHI affords you. This is a scheme run by Ofgem. The Government’s regulatory body for gas and electricity. This is when you’re rewarded financially for producing ‘green’ heat. The amount of money received per quarter can vary a large amount. This depends on factors such as a home’s age, the amount of insulation, wall materials, the type of heating system, etc. All that said, the payments aren’t insignificant. They make a GSHP’s installation, not just justifiable, but actually preferable to other domestic heating options.

With the increasing societal commitment to greener living, ground source heat pumps are only going to become more popular moving forward. If you’re going to have one installed, it’s crucial that you utilise a trusted contractor that really know what they’re doing. So, if you want  to find out more about our geothermal borehole drilling, then get in touch! Contact Borehole Solutions today on 01733 200 501. Or visit our instagram page to see an onsite into previous work we have carried out.