Ground Source Heat Pump Association


Renewable Heating

Renewable energy can only come from sustainable resources. It cannot come from burning fossil fuels which releases CO2 at a far greater rate than the rate at which carbon was captured by photosynthesis in the carboniferous era.

The most obvious source of renewable energy is from the sun. However, the sun yields most of its energy on long summer days and the need for heating is greatest on cold winter nights.

Solar thermal panels are good at capturing renewable heat. However, unless this heat can be stored until it is needed there is little merit in capturing this heat for space heating purposes.

The ground itself is warmed by the heat of the sun over the long summer months. The top two metres of the surface are the layers most affected by the sun, but as the sun has been shining for millions of years the warmth of the sun has penetrated deep into the surface and down to considerable depths. The ground is capable of holding a lot of heat – although it takes heat with reluctance and yields it with reluctance. The ground acts as an enormous store of heat energy and reacts with substantial thermal inertia. It manifests its extensive natural capacity to perform seasonal thermal energy storage.

The challenge has been how to make use of this almost unlimited source of "low grade heat". The natural temperature of the ground in the UK, below the top six metres, is very close to 10°C. This "low grade heat" is not of itself sufficient for heating. However, it is possible to extract the heat by passing water though pipes in the ground and transferring the heat to a heat pump which can concentrate the heat up to 50°C by compressing refrigerant gases. At 50°C the temperature is sufficient to provide space heating if the water is passed through an array of underfloor heating pipes.

This enables a ground source heat pump system to provide renewable heating without burning any fossil fuels and without releasing CO2, or any other greenhouse gases.

Installation of Ground Source Heating Systems

To get the full benefit of a ground source heating installation you will need to employ someone with design and installation experience of ground source heating systems. A ground source heating system may not perform well unless it is incorporated into a good design by someone who understands the needs of the building, the use to which the building is being put and the local geology.

For more information on installation of ground source heating from an experienced source please contact one of our members.

Extending the advantages of Renewable Heating to provide Renewable Cooling

The advantages of installing renewable heating can be extended to providing renewable cooling.