Understanding Ground Source Heat Pumps

Understanding Ground Source Heat Pumps

Heat your home or business from the ground

Ground Source Heat Pumps (GSHPs) use pipes buried in the ground to extract heat which is used for indoor radiators, under-floor heating systems or warm air heating systems and hot water in your home or business.

Beneath the surface the ground stays at a fairly constant temperature. This means that a GSHP can be used throughout the year – even in the middle of winter.
"Heat Pumps can provide 100% of a home’s heating and hot water."

How does a ground source heat pump work?

Heat from the ground is absorbed at low temperatures into a fluid inside a loop of pipe (a ground loop) buried underground. The fluid then passes through a compressor that raises it to a higher temperature, which can then heat water for the heating and hot water circuits of the house. The cooled ground-loop fluid passes back into the ground where it absorbs further energy from the ground in a continuous process as long as heating is required. The heat pump requires electricity to run, but uses far less electrical energy thus saving you money in the long run. The heat pump performs the same role as a boiler does in a central heating system, but it uses ambient heat from the ground rather than burning fuel to generate heat.

Benefits of ground source heat pump?

  • Can reduce you carbon footprint: heat pumps can lower your home’s carbon emissions, depending on which fuel you are replacing.
  • No fuel deliveries required.
  • Can provide space heating and hot water.
  • Can lower fuel bills, especially if you are currently using conventional electric heating.
  • It’s often classed as a ‘fit and forget’ technology because it needs little maintenance.


Costs of installing a typical system range from about £11,000 to £15,000. Running costs will depend on a number of factors – including the size of your home and how well it is insulated.


Savings will vary depending on many factors, some are outlined below. It is important that the system is controlled appropriately for your needs.

  • Your heat distribution system - If you have the opportunity, underfloor heating can be more efficient than radiators because the water doesn’t need to be so hot. If underfloor heating isn’t possible, use the largest radiators you can. Your installer should be able to advise on this. 
  • Your fuel costs - You will still have to pay fuel bills with a heat pump because they are powered by electricity, but you will save on the fuel you are replacing. If the fuel you are replacing is expensive you are more likely to make a saving. 
  • Your old heating system - If your old heating system was inefficient, you are more likely to see lower running costs with a new heat pump. 
  • Water heating - If the heat pump is providing hot water then this could limit the overall efficiency. You might want to consider solar water heating to provide hot water in the summer and help keep your heat pump efficiency up.

Domestic or commercial options

Rexel Energy Solutions can supply a range of single and three phase heat pump models from DimplexAll can provide hot water flow temperatures of up to 70°C.

What savings can be made?

Field trials performed by the Energy Saving Trust using ground source heat pumps have demonstrated that the following savings can been made when replacing an existing heating system boiler in a 3-bed semi-detached home.

Servicing and maintenance

You can expect a Ground Source Heat Pump  to operate for 20 years or more, but they do require regular scheduled maintenance. A yearly check by you and a more detailed check by a professional installer every three to five years should be sufficient. The installer should leave written details of any maintenance checks you should undertake to ensure everything is working properly.

Dimplex - Heat from the ground

Dimplex ground source heat pumps can provide 100% of a home’s heating and hot water, without the need for supplementary heating. Designed to provide a sustainable heating solution for virtually any scenario, they are perfectly suitable for use with radiators or under-floor heating systems, not forgetting domestic hot water. High temperature models are available that can provide water flow temperatures up to 70°C, which provides the ability to fulfil the full hot water requirements for a property without the need for supplementary electric heating.