How does it work?
Geothermal heating uses the earth’s natural heat that is trapped in the ground and converts it to energy. Below the ground’s surface, temperatures hover around 11-12 degrees, making it a reliable and renewable heat source. A ground source heat pump is then used to extract the heat, pumping it through a series of pipes and into your home.
One of the major benefits of geothermal heating is that it is much better for the environment. Although the heat pump itself requires electricity to run, the energy it produces is constantly renewed, meaning it has a much smaller impact compared to other heating systems.
Regardless of what existing heating system you have in your home, geothermal heating is compatible with just about every type. This includes underfloor heating systems, air heating systems, hot water systems as well as radiators.
See also: Save Money on Your Heating Bill
How much does it cost?
The cost of installing a geothermal heating system can vary, but will typically be between £13,000 and £20,000. Running costs will depend on the size of your home and how well insulated it is. The Centre For Sustainable Energy estimates costs to be around £655 a year.
See also: The Heat Beneath your Feet
How much can you save?
How much you will save with a geothermal heating system largely depends on the type of fuel you are replacing. For example, a four bedroom detached house where you are replacing electricity, you could save around £1,420 a year. If you are replacing LPG you would more likely save around £1,260, whereas if you are replacing oil, you stand to save approximately £620.
The renewable heat incentive (RHI), recently introduced by the UK Government, is another way to maximise savings. Payments are designed to reward those who make the clean investment in geothermal heating and are made quarterly over a seven-year period.
Insulation: The better your home is insulated, the better a geothermal heating system will work. So it’s important to consider how well your home is suited before making the switch.
Compatibility: Geothermal heating is best suited for an underfloor heating system. If you have a different type of heating system, ask your installer to give a detailed outline of the costs and benefits.
Heat pump: The actual size of a heat pump is similar to that of a large fridge, so you will need to think about where you will be able to fit it in your home. Installing it in an outbuilding or basement is also an option.
See also: Geothermal Heating Explained
Closed-loop or open loop?
There are two different types of geothermal heat pump systems available: closed loop or open loop. The best choice for your home will depend on the climate, soil conditions, available land, and installation costs in your local area.
A closed-loop system will pump an antifreeze solution through a series of closed pipes buried in the ground. Heat is then transferred between the refrigerant in the heat pump and the antifreeze solution in the closed pipes.
An open-loop system uses surface water or water from a well as the heat exchange fluid, which then circulates directly through the heat pump system. Once it has been circulated, the fluid is then returned to its original source.
See also: Planning for Winter Warmth