What is a geothermal heat pump?
A geothermal heat pump (aka ground source) is one of the most efficient ways to heat up your house or your office building. Geothermal draws natural energy stored in the ground and turns it into useable space heating and hot water which means you do not need any fuel deliveries such as oil, coal, LPG or biomass. The energy available in the ground is plentiful and replenished constantly by sun and rainwater.
To extract the energy stored in the ground there are different methods utilised which are listed in the questions below. For every 1 unit of electricity used by geothermal heat pumps, it gives out roughly 4.5 units of heat or sometimes higher making geothermal heat pumps highly efficient. Once geothermal heat pumps are installed, it needs very little maintenance and if designed and installed by professionals will last a very long time. Heat Pumps Scotland provides some of the most efficient ground source heat pumps on the market today.
Why do people call ground source geothermal heating?
It’s no surprise people often refer to ground source heat pumps as geothermal heating. This is due to the fact that the energy extracted from the shallow ground or from the core of the earth (geothermal) the energy source stays the same, the earth, but in reality geothermal refers to the heat generated from the core of the earth which is visible in hot springs and volcanos. So it’s not entirely incorrect to call ground source geothermal as at the end of the day the energy being extracted is from the ground.
How does a ground source heat pump work?
The ground source heat pump utilises ground collector pipes which has heat transfer fluid running through them. This heat transfer fluid collects heat from below the ground surface and pushes it through a compressor located inside the ground source heat pump via a plate heat exchanger. The compressor takes the heat collected and pushes it through at very high pressure which in turn raises the temperature of the refrigerant to a level which is suitable to provide space heating and hot water for the domestic or commercial premises. This cycle repeats itself constantly.
Different methods of extracting heat from the ground.
Heat can be extracted from the ground using the mentioned methods below;
Horizontal ground loops
Low cost, no expertise required, most commonly used method. Not suitable for properties with little or no ground available.
Less digging required. Less area required compared with horizontal ground loops. Can sometimes be laid inaccurately leading to problems.
Closed-loop & open loop boreholes
Discreet and compact, can be installed in mostly all types of properties. Minimal ground disruption. Minimal space requirement. Stable temperatures below 10 meters.
Submerging ground loops into rivers, lakes and ponds. Extremely efficient, excellent heat transfer. No drilling or digging required. Lowest cost to install.
How much does it cost to install a geothermal heat pump?
Ground source heat pump installations vary in cost greatly depending on the type of ground collector system used but for an average 3 to 4 bedroom house with reasonable insulation levels the geothermal heating system can cost anywhere between £18,000.00 – £32,000.00.