Heat pumps benefits and types explained

How do heat pumps work?

A device that provides heat energy from a source of heat to an alternate destination, there are two types of heat pump commonly used for warming homes.

 

Air Source Heat Pumps (ASHPs)

 

Absorbing heat from the outside air, air source heat pumps (ASHPs) can be used to heat radiators, under-floor heating systems, warm air convectors and hot water.

Using electricity to run, ASHPs extracts heat from the outside air in the same way that a fridge extracts heat from the air within it. ASHPs are able to get heat from the air even when the temperature is as low as -15° C.

 

How does an ASHP work?

 

Costing between £7,000-£14,000, ASHPs work by absorbing low temperature heat from the air into a fluid. This passes through a compressor where its temperature is increased before the higher temperature heat is transferred to the heating and hot water circuits in the house.

There are two main types of air source heat pump system:

 

An air-to-water system 

 

This distributes heat via the wet central heating system. Heat pumps work much more efficiently at a lower temperature than a standard boiler system would, making them suitable for under-floor heating systems or larger radiators, which are designed to release heat at lower temperatures over longer periods of time.

 

An air-to-air system 

 

This produces warm air, which is circulated by fans to heat the home. It’s unusual for an air-to-air system to also provide hot water.

 

The benefits of ASHPs

 

Once installed ASHPs will:

 

  • Lower fuel bills, especially when replacing conventional electric heating
  • Provide an income through the Government’s Renewable Heat Incentive (RHI)*
  • Lower a property’s carbon emissions, depending on which fuel you are replacing
  • Heat your home and provide and hot water
  • Require little maintenance

 

Ground Source Heat Pumps (GSHPs)

 

Ground source heat pumps (GSHPs) circulate a mixture of water and antifreeze around a loop of pipe, which is buried in the garden, to extract heat from the ground. This heat can be used to heat radiators, under-floor or warm air heating systems and hot water.

 

How do GSHPs work?

 

Costing between £11,000-£15,000, GSHPs work by absorbing low temperature heat from the ground into a fluid inside a loop of pipe, buried underground. The fluid passes through a compressor that raises it to a higher temperature, which can then heat water for the heating and hot water circuits in the house.

Typically the loop is laid flat or coiled in trenches about two metres deep. If however there isn’t enough space in your garden, you can install a vertical loop down into the ground to a depth of up to 100 metres.

As the ground stays at a fairly constant temperature under the surface, GSHPs can be used throughout the year.

 

The benefits of GSHPs

 

Once installed GSHPs will:

 

  • Lower fuel bills, especially when replacing conventional electric heating
  • Provide an income through the Government’s Renewable Heat Incentive (RHI)*
  • Lower a property’s carbon emissions, depending on which fuel you are replacing
  • Heat your home and provide and hot water
  • Require little maintenance

 

*You may be able to receive payments for the heat you generate using a heat pump through the Government’s Renewable Heat Incentive (RHI)

ASHPs and GSHPs are an eligible measure under the UK government’s Green Deal, a financing mechanism that lets people pay for energy-efficiency improvements through savings on their energy bills.

For more information about heat pumps, installers and planning restrictions visit the Energy Saving Trust website.

Information and other materials on this website are not intended to constitute professional advice and should not be relied upon. Please see our Terms of Use for further details.

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