Note, The original boiler was 65% efficient. In 1982, a new boiler could have been 88% efficient (in theory)

Swimming pool heat pump pollution figures for various fuel types.

1 Pollution figures for oil 0.27 kg CO2/ Kwhr
Boiler efficiency 65 %
Net Oil pollution figure 0.42 kg CO2/ Kwhr

2 Boiler efficiency 86 %
Net Oil pollution figure 0.31 kg CO2/ Kwhr

3 Pollution figures for north sea gas 0.19 kg CO2/ Kwhr
Boiler efficiency 90 %
Net Gas pollution figure 0.21 kg CO2/ Kwhr

4 Pollution figures for electricity 0.47 kg CO2/ Kwhr
Heat pump efficiency (COP) 4.25 heat output/ electric input
Net pollution figure HP 0.111 kg CO2/ Kwhr

Pollution and cost figures taken from www.johnwilloughby.co.uk
The graphs make these assumptions
Origional cost of oil heating £1,700 per year , oil at 20p/lit
Origional oil boiler 65% efficient, new boiler, 88% efficient, £2,000 to install
Heat pump £5,000 to install.
Inflation ignored, so cost figures only give comparison between types.

Data for Lazonby and Greystoke swimming pools

Note, both pools are of similar size (around 175m²), and have common components except from the evaporator type.

Compressor Maneurop MT80 (reciprocating hermetic)
Refrigerant R22
Heat output 24 to 30kW
condenser Cu-Ni, shell and tube
Expansion valve Sporlan balanced-port

Lazonby data
River heat-exchanger 12 x 15m circuits of 1/2" o.d. copper
River flowrate 1.9 lit/sec.
Pump power 370 watts.
Return temperature Approx 3K lower than intake temperature.
Compressor run hours for 1982 1918 h.
Run time over the 112 day season 72% of the time
Power input 5.6 to 7kW
Average COP Lazonby (river source) 4.25

Greystoke data
Air heat-exchanger face area 1.88m x 1.12m
Air flow 16,000m³/h.
Fan power 3 x 450 watts
Compressor run hours for 1982 2057 h.
Power input 6.2 to 7.5kW
Average COP Greystoke (air source) 4
 
 
 

 
             
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