GAHPs can be used as a direct replacement for gas-fired traditional and condensing boilers due to the ability to reach temperatures as high as 70°C and produce domestic hot water. The potential power savings when converting from traditional boiler technology to a GAHP exceeds 100%.
The efficiency of a GAHP is measured by its Gas Utilisation Efficiency (GUE), which is the ratio
of the energy it supplies (i.e. heat transferred to the medium to be heated) to the energy consumed by the burner.
The GUE varies according to the type of heat pump and operating conditions, and generally has a value of approximately 1.5. This means that for each kWh of fuel burnt, it will supply about 1.5 kWh of heat energy to the medium to be heated.
This differs from the Coefficient of Performance (COP) of an electric heat pump in the fact that gas rather than electric is the primary heat source. To make a complete comparison between COP and GUE you need to take into account the losses in grid-electric generation, typically, this process is only about 36% efficient.
Comparison of operating efficiency
The three diagrams below show the different quantities of natural gas required to produce the same amount of heat energy:
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Gas absorption heat pump
Different technologies CO2 output in grams
- The graph shows the grams of CO2 produced per kWh from 8 different heat generating technologies.
- Through no requirement for an electrical compressor a GAHP only requires a small amount of energy to pump the refrigerant solution and circulate the air.
- This enables a GAHP to achieve less than half the emissions of an electric air source heat pump and around a 40% reduction in CO2 emissions when compared to the latest condensing gas boilers.
For further information on the improved efficiency of the GAHP offering please contact +44 (0)845 300 8882 or email gahp@energ.co.uk.
