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No bills yet - apparently I'll get December and January together, lovely. The below might be of interest to people. The ambient is the 24hr average as an FYI
@heat-pump-newbie the heat pump gives it to me a statistic along side power use, heat delivered etc. I assume its just the average temperature across the day
Hmm, Mars - "2.39 MWh ... this December it would have cost us a staggering £526."
Think I'll check my figures:
300m2 Chalet Bungalow, 12kW ASHP, 30 Amp Storage AGA and wood burner in lounge.
December Energy usage: Day 1132 kWh, Night 1752 kWh, Total 2.89MWh.
Current Fixed Rate (24p/9.5p per kWh) = £438
Best Big 6 Fixed Rate now (44p/23p per kWh) = £902
Yep, very scary !!
@jon-c just had a look on a comparison site. 8.5p/KW for gas is the lowest price and 29p/KW for electricity. Ouch. Still, that's a cop of 3.4 if you wanted to switch to a heat pump...
Posted by: @jon-cHmm, Mars - "2.39 MWh ... this December it would have cost us a staggering £526."
Think I'll check my figures:
300m2 Chalet Bungalow, 12kW ASHP, 30 Amp Storage AGA and wood burner in lounge.
December Energy usage: Day 1132 kWh, Night 1752 kWh, Total 2.89MWh.
Current Fixed Rate (24p/9.5p per kWh) = £438
Best Big 6 Fixed Rate now (44p/23p per kWh) = £902
Yep, very scary !!
Jon,
we had a 30 amp night storage Aga when we moved in and it was nice but very expensive to run. We just couldn't justify it so it had to go.
Kev
@kev-m, what was your heat pump usage in December?
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@kev-m, that's very satisfactory. That would have been around £76 this time last year with Symbio. But still very good.
New to heat pumps? Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
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1224kWh here for our largish 4 bed house (which also housed four 20 somethings over Christmas fortnight as well as us) in total for Dec including the ASHP, plug in hybrid car (Golf GTE fantastic!), etc. ASHP is a 12kW Vaillant Arotherm plus with a SCOP of 2.5 inc DHW of which we made lots looking after the young people.
Similar @witchcraft we used 1179kWh 10th Dec to 9th Jan. 234kWh was on my cheapest overnight tariff when I heat hot water, run the dishwasher and charge the EVs
Approx 705kWh of the total were from the Daikin ASHP.
So I was happy with this. My MCS predicted ASHP usage is 54kWh per day for January. I am well below this.
Daikin Altherma 3H HT 12kWh ASHP with Mixergy h/w cylinder; 4kW solar PV with Solic 200 electric diverter; Honda e and Volvo EX30 Ultra Twin Performance electric vehicles with Myenergi Zappi mk1 & Ohme chargers
Still battling with our installer to get our MMSP sorted out so having to guess a bit about our ASHP usage, but overall usage for our 240m2 3-storey house was 1290kWh + a measly 90kWh from solar PV (lowest we've ever had for December by quite a long way).
Previous 6 years average for grid + solar, pre ASHP install, was 604kWh, so as a rough estimate we used 776kWh on heating. This assumes zero solar PV export, which is probably not quite the case, but our iBoost would have used most of the excess, so it should be fairly close.
Wishing we could also get our smart meter to actually connect to the metering grid, then we might be able to look for a lower overnight tariff, but we're currently on a fixed rate of 20p/kWh (until October), which, given the current state of the market I'm not complaining about!
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