EU Energy Efficiency Labels Explained
31st January 2017
How to Reduce Your Energy Consumption and Your Energy Cost
31st January 2017

Ground To Water Heat Pumps

GOING GREEN? Thousands of people have been empowered not only to save money and energy but also to conserve our planet's resources for future generations.

There are countless reasons why more and more smart people are deciding on other alternatives to fossil fuels for their heating. Here are a few things that may encourage you on the benefits of going green.

How It Works

A mixture of water and anti-freeze is pumped around the ground loop and absorbs the naturally occurring heat stored in the ground. The pump itself consists of an evaporator, a compressor and a condenser - together these take the heat from the water mixture, and transfers it to your domestic heating system and increases the temperature in the process. A ground source heat pump increases the temperature from the ground by between one and a half and four times – so if the ground temperature is 12°C, the output would be between 18 and 48°C).

This heat can then be used in a radiator, hot water or in an underfloor heating system. Whether you'll need an additional back-up heating system will depend on the individual home.

What are the advantages?

  • Ground source heat pumps generate less CO2 than conventional heating systems.
  • The Energy Saving Trust (EST) says that a 'typical' ground source heat pump could save you between £410 and £2,000 a year depending which existing heating system you are replacing. 
  • You can get financial help towards the cost of a ground source heat pump. The Incentive scheme provides payments to householders who have a heat pump.
  • You need to use electricity to power the pump, which circulates the liquid in the ground loop, but for every unit of electricity used by the pump, you get between two and four units of heat – making this an efficient way to heat a building.
  • Cheaper Economy 7 electricity tariffs can be used to lower the cost of electricity to power the heat pump, and some suppliers may provide a heat pump tariff. Alternatively you may want to consider solar photovoltaic panels or a wind turbine. 

What are the drawbacks?

  • Installing a ground source heat pump is expensive, and may include an extra cost of installing underfloor heating if required
  • Ground source heat pumps are generally not suitable for properties with existing gas-fired central heating as the technology works at lower temperatures, making it better suited to homes with underfloor heating. You may need a separate electric heater to help provide all your heating and hot water needs.
  • The groundwork required to dig the trench can be expensive and disruptive. Planning permission may be required if space is at a premium and you need a borehole. Ground source heat pumps tend to be better suited to new-build homes as they can be planned as part of the construction process.
  • You still need to use electricity to drive the pump, so a ground source heat pump can’t be considered completely zero-carbon unless a renewable source, such as solar power or a wind turbine provides this.
  • Your home may take longer to heat up, and you'll need to have your heat pump on for more hours a day than you would with a boiler.