Ground Source Heat Pumps
What is a Ground Source Heat Pump?
Ground source heat pumps or GSHP use pipes, known as collectors, buried in your garden to extract heat from the ground.
Here at EnergyZone we have the knowledge and skill set to utilise a range of different ground collectors, from bore holes to horizontal loops, to design the most cost effective and applicable solution for your project based upon property requirements and what the site has available in terms of area.
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 it’s heat through a compressor that raises it to a higher temperature, which can then heat a separate water circuit for the heating and hot water needs 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.
What type of ground collectors are available?
There are three main methods of extracting heat from the ground which we use here at Energyzone.
- Horizontal loop
- Bore hole
- Helical coil
If sufficient area is available at the site, typically around 2-5 times the floor area of the property, we would look to use a horizontal loop system. Normally this loop is laid flat into trenches about one meter deep, one meter wide. If there is not enough area available for this collector method, boreholes can be utilized, with one or more vertical loops sent to a depth of up to 100 meters or more. The helical coil type method sits between these two methods, offering a tighter collector area with slightly less cost than a bore hole solution.
In addition to these, we are also able to install mini bore collectors, foundation collectors, and in some rare cases, slinkies offer the best solution.
Renewable Heat Incentive
The Renewable Heat Incentive (RHI) that ground source technology attracts is the highest of the heat incentives. This is in part to help offset the extra installation costs associated with this solution verses say air source.
Currently the tariff rate for new ground source installations is 20.46p/kWh* for domestic installations with an upper limit of 30000kWh for deemed water and space heating combined. If your property's EPC figure is higher than this payments are simply throttled back to this figure.
Below is an example of what this equates to in terms income for a standard 3-4 bed detached property;
Property size = 200m²
Property age = 1980’s
Property insulation standard = filled cavity and required 250mm of loft insulation
Payment per quarter = £1,200
Payment over 7-years = £33,600 (excludes year on year inflation percentages)
* Tariff rate taken from Ofgem with the rate running from 1st April until 30th June 2018.