The systems can produce anything from 1kW to 150kW depending on your requirements and budget. However, the systems do require electricity to power the pumps that move the fans. A general rule is that for every 1kW of electricity used for the pumps, the heat pump should produce the equivalent of 3kW of energy of heat (CoP of 3:1 or 300%).
The coefficient of performance is affected by how much energy you need the heat pump to produce. If you require the heat pump to heat the water in the house to around 60 degrees (i.e. in winter), then the CoP is likely to be around 2.0, whilst heating the water to just 35 degrees (i.e. in Summer) will create a CoP of around 3.5. Also, Heat Pumps that are required to provide domestic hot water, which requires a higher temperature than domestic heating, will have a lower CoP, in the 2 area. That said, more traditional methods of heating, such as immersion heaters, have a CoP of 1 or even less than this (meaning more energy input is required than the outputted heat). For example, Gas and Oil boilers have efficiency ratios of 85%, equivalent to a CoP of 0.85.
The performance of the system is also more suited towards under floor heating systems as the water temperature provided by the ASHP (55 degrees) is lower than that provided by more traditional fossil fuel methods (around 75-80 degrees). If it is used for radiator systems then a back-up boiler may be required to boost the system.
If the system is required to provide domestic hot water, a thermal store will be required also. This is similar to a hot water tank, although tends to be larger, with a larger heat exchanger coil within the cylinder.
Home pages of interest in this section are:
Pages of interest in this section:
- What is an Air Source Heat Pump?
- How do ASHP’s work?
- How much energy do ASHP’s produce?
- How much do ASHP’s cost?
- Cash Flow Analysis of ASHP’s
- GSHP’s versus ASHP’s
- ASHP’s in Conjunction with Solar PV
- GSHP’s and ASHP’s in practice
