Questions & Answers about Ground Source Heat Pumps

How efficient is a ground source heat pump system?
Ground Source Heat Pumps are very energy efficient. For each kilowatt of electricity used to run the Ground Source Heat Pump, three to four kilowatts of thermal heat are delivered to the building.

I haven't heard of these systems before, are they new?
In the United States and Europe, especially Sweden, Austria and Germany, the use of Ground Source Heat Pumps (GSHP) is very common. The ground source heat pump was invented more than fifty years ago, and continuous development has greatly improved its reliability and efficiency. It is a proven, safe and cost-effective.

How big is a heat pump?
A typical heat pump unit for a domestic installation is about the same size as a tall fridge.

Can it supply hot water for the house?
The heat pump will heat the water to 50*C and once weekly a boost will heat the water to 65*C to clean the water of any bacteria.

Can the systems provide cooling?
Some heat pumps do provide heating and cooling but there are no grants for these systems.

Can I use a standard domestic electricity supply or does it have to be 3 phase?
Single phase is fine for most domestic heat pumps. Three phase would be essential for larger units.

Is a Heat Pump suited to new builds?
Very well suited. The insulation values on new builds make the installation of heat pump a good choice. It's cheaper when installing on a new build and the installation of the ground loops can be done when the footings are excavated.

Does a Heat Pump work with underfloor heating?
Heat Pumps are ideally matched to modern low temperature underfloor heating.

I have an older property with radiators, is this okay?
If the property is well insulated and the radiators are large enough then yes you should be able to install a heat pump. The radiators that would have been sized for your existing gas/oil boiler would be oversized and generally a heat pump will be able to use them. Upstairs is usually less of a problem as bedrooms are normally kept at lower temperatures.

How much will a Heat Pump cost to install?
You will be looking at a fully installed price of £10,000+

Could I install the heat pump outside in my garage or basement?
Usually this is no problem, the heat pump must be kept dry, and it shouldn't be installed where water damage might occur.

What are the options for the ground loops or ground collectors in the garden?
A typical heating-only installation for a medium sized, new build detached house would need at least two narrow trenches, each 300 mm wide and 40 to 50 metres long and 1 metre deep. The trenches can be straight or curved and laid in any direction to suit your site, providing they are always a minimum of 2 or three metres apart. A mechanical digger, such as the type used to dig conventional foundations and footings, can dig the trenches and backfill them after the ground loops have been installed. Your builder and/or digger driver will be able to do this work and plan it to ensure the minimum of disruption to your site. Once completed, and the ground loops pressure tested and buried, your renewable energy collection system can basically be forgotten. Boreholes can be used instead of trenches if there is not enough garden area. We would drill down about 50m, usually three or four times per property.

My land is very wet, can I use this?
Wet land is better at conducting heat so the wetter the better.

We using electricity, are GSHP systems really renewable?
If you’re using fossil fuelled electricity to power your heat pump, no not really. You need to get your electricity from a green electricity provider, if you use this to power your heat pump, your property will be totally heated from renewable energy with zero carbon emissions.

Can I dry out my new build with a heat pump?
The heat pump is not designed or sized to provide the greatly increased heat demand during the initial drying out of a newly constructed building. During this period, and until the building is completely finished, supplementary heating may well have to be supplied by the owner/builder using separate equipment.