Ground Source Heat Pumps Design & Installation in Devon

A ground source heat pump (GSHP) extracts solar energy stored as heat in the ground using buried pipes. This heat can then heat radiators, underfloor or warm air heating systems and provide hot water in your home. Although heat pumps have some impact on the environment as they need electricity to run (you might consider installing solar photovoltaic panels or a wind turbine for a greener source of cheap electricity) the heat they extract from the ground or water is constantly being renewed naturally making it a sustainable, renewable source of energy.

Where suitable we install ground source heat pumps to provide eco-friendly heating and hot water to homes and offices in Devon including the more remote rural areas such as Dartmoor.

How ground source heat pumps work

A mixture of water and antifreeze is circulated around a buried loop of pipe, called a ground loop. The fluid, warmed by the heat in the ground, then passes through a heat exchanger into the heat pump. The ground stays at a fairly constant temperature under the surface, so the heat pump can be used throughout the year – in winter the ground is warmer than the air and buildings above.

A heat pump delivers water at a temperature that is ideal for underfloor heating. The water can be heated to 50’C can also be used for a traditional radiator system, although the radiators have to be larger than for a traditional heating system (oil or gas).

Diagram of ground sourced heat pump in a home

The length of the ground loop depends on the size of your home and the amount of heat you need. Longer loops can draw more heat from the ground, but need more space to be buried in. If space is limited, a vertical borehole can be drilled instead.

Ground source heat pumps take renewable energy from the Earth’s surface

The top 15 metres of the Earth’s surface maintains a relatively constant temperature –  approximately 12 – 14 degrees Centigrade in Devon and the South West. This renewable energy can be used to heat buildings indirectly. The heat that heat pumps extract from the ground, air, or water is constantly being renewed naturally.

The benefits of ground source heat pumps

Heat pumps work at lower temperatures, than gas and oil, over much longer periods. During the winter they may need to be on constantly to heat your home efficiently. You will also notice that radiators won’t feel as hot to the touch as they might do when you are using a gas or oil boiler.

Measuring the efficiency of a heat pump.

The efficiency of a ground source heat pump is measured in Coefficient of Performance (CoP). This is the ratio of units of heat output for each unit of electricity used to drive the compressor and pump for the ground loop. A CoP of 4 means that for every kilowatt of electricity put in, you get 4 kilowatts of energy in the form of warm water. The flow temperature of the warm water is typically between 35 degrees Centigrade and 45 degrees Centigrade; much lower than achieved by a domestic boiler. The units can reach higher temperatures, but the CoP is then compromised by keeping the temperature at the lower end of the scale ensures the system operates efficiently.

Ground Water Heat Pump

Ground water heat pumps draw water from standing water around the property such as a lake, pond or a well. Water holds onto its heat very effectively and so these systems provide a large, almost limitless, amount of energy for the heat pump. The only down side of course is you need some water near your home or office. These systems can also be used on bore hole installations. Of all the heat pump systems these are the most efficient.