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Posted by: @morganI don't dispute the difference in temps. I'm generally unimpressed with the overall consumption. I don't dispute that this January has been much colder than last. So actually my grievance is with the consumption and the fuel price. I live in rural west midlands, UK.
Apologies, I thought you were complaining about the comparison between the two months. My figures on the temperature differences were for Birmingham Airport so perhaps not too different to where you are.
The fuel price is unfortunately almost purely a political decision and successive governments have declined to switch policy costs, largely associated with the environment, from electricity to gas, or to break the, now largely anachronistic, link between electricity price and gas price. These are somewhat incoherent policy wise but political dynamite to change.
Do you know what COP you are getting?
If you would like to post some details of your system it may be that some on this forum can comment on possible improvements. If you have any of the following:
- Buffer tank (other than a 2 port volumiser)
- Low Loss Header
- Plate Heat exchanger
- Third party controls (including thermostats) or timers not specifically designed for heat pumps
- TRVs on anything than a minority of radiators (unless set to a temperature above the desired temperature)
then its quite possible improvements can be made.
Several on here will, I am sure, be keen to offer suggestions if this is the case.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
ASHP for heating and hot water:
January 2024 - 542kWh
January 2025 - 578kWh
Daikin 8kw. 4 bedroom detached house, new build, 150 sq m. Rural Cambridgeshire.
Underfloor heating downstairs, radiators upstairs.
Around 370kwh for 2024 to around 490kwh 2025.
Did try running it 24hrs over the 1st week of Jan, but decided it was of no benefit, so won't be doing that again.
538m², new build. Grant 13kw R32, West Midlands area
Are you using Weather Compensation?? Likely to save 15 - 30% vs fixed flows
Are you on a time of use tariff? Over a year savings can be substantial. Especially if you have a battery too. With solar & battery my average unit cost last year was 12p.
Somerset. 200m2. Half old with poor insulation. Half modern
My heat pump has metered usage but I've only recorded since 2023 when I moved to weather compensation. installed Aug 2020.
16kw LG Therma V
JAN usages
2021 est with fixed temps 1500kwh
2022 est 1500kwh
2023 1200 kwh (training weather comp from Dec22)
2024 1127kwh
2025 1050kwh
N.b. Jan 2025 included a day with power cut and cold weather encouraged extra use of wood burner. Hard to compare like with like. But definite conclusion of weather comp savings.
FULL YEARS
2021 est 8050
2022 est 8050
2023 5782 kwh
2024 5741 kwh
Listed Grade 2 building with large modern extension.
LG Therma V 16kw ASHP
Underfloor heating + Rads
8.7kw pv solar
3 x 8.2kw GivEnergy batteries
1 x GivEnergy Gen1 hybrid 5.0kw inverter
Manual changeover EPS
MG4 EV
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
2 ESS Smile G3 10.1 batteries.
ESS Smile G3 5kw inverter.
Listed Grade 2 building with large modern extension.
LG Therma V 16kw ASHP
Underfloor heating + Rads
8.7kw pv solar
3 x 8.2kw GivEnergy batteries
1 x GivEnergy Gen1 hybrid 5.0kw inverter
Manual changeover EPS
MG4 EV
I use degreedays.net
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Posted by: @uk_pete_2000Around 370kwh for 2024 to around 490kwh 2025.
Did try running it 24hrs over the 1st week of Jan, but decided it was of no benefit, so won't be doing that again.
538m², new build. Grant 13kw R32, West Midlands area
Crikey how did you manage those figures?
310m2 here
Jan 24 1865
Jan 25 2192
Whole house electric usage. It’s a mortgage worth of electricity.
Edited (modified) to end quote at correct point
@roamingbull Whats the assessed heat loss of your house at what design temperature, and whats your house construction? Even estate newbuild is pretty good these days as regards loss so with an older house you cant expect to get anywhere near.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Posted by: @uk_pete_2000Posted by: @uk_pete_2000Around 370kwh for 2024 to around 490kwh 2025.
Did try running it 24hrs over the 1st week of Jan, but decided it was of no benefit, so won't be doing that again.
538m², new build. Grant 13kw R32, West Midlands area
Crikey how did you manage those figures?
we have a very well 400mm Insulated house, etc Passive standard
I don’t have the figures off hand as not in the country.
Old Barn, completely stripped out, 150mm underfloor insulation and in walls and roof.
I’m actually thinking was it enough.
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