>> I've already forecast £3,000 of electric this year
>> >> and looks as if half of that will fall in Dec-Feb. We do have
>> a
>> >> high phantom load here as well, what with cameras, ventilation system, alarm, outside lights
>>
>> >>
>>
>> How much do you think it would if you had gas? I've seen a few
>> reports of the heat pumps, they look pretty expensive to run. A lot more than gas.
Sorry - long answer.
Good question, which I'm trying to assess. The £3,000 is based on current prices and about 8,200kWh. Of that, heat pump is about 4,300kWh, the remainder other stuff - although I think up to 1000kWh of the "other" might be heating-related being the cost of running the UFH pumps!
However the heat pump is averaging 38kWh in the current weather, out of a consumption of 54kWh total. Wife likes to be warm, and the mean outside temp for the last few days has been c. -1.5 degrees C. Before that, with a mean temp of 4.5 C, the heat pump was only 24kWh/day - so that 6 degree drop has cost £4-£5 a day.
I believe gas is currently about 10p/kWh and electric about 35p. For heating the cost should therefore be similar BUT there is the question of how it's used. I think if we had a gas boiler, I'd be stopping it at say 10pm and firing it up at 5am. We have been told to run the heating and DHW 24/7. This is because (1) the underfloor heating is not very reactive, from cold it will take at least 24 hours to warm the house, and (b) there is an overhead to starting the heat pump from cold so it becomes less efficient overall when it is stopped and started.
However I'm pretty sure we can tweak it. Maybe stop it at 9pm and restart at say 4am. Or heat water twice a day instead of all the time. I can also adjust the thermostats better - at the moment the unused and lightly used rooms are at 17-18 degrees. I don't want to keep them too cold but there's scope there. I'm getting a decent benchmark before I start complicating matters.
What I will say is that there seems to be plenty of scope with heat pumps for terrible installations and also that installers rarely give much information to users. If you're lucky, your installer will use a reasonable initial set up but that isn't always the case.
One really annoying thing is that when the unit is connected to the internet, the manufacturer collects very detailed data of which a very reduced and simplified subset is all I can access. The hourly data is overwritten every day for example. This is very common. One manufacturer, I have just read, (Global Energy Systems) only gives free access to this for 3 years, after which they want £150 a year for access!
I think my installation is probably OK but some of the information I am getting from the associated app looks garbage.
** Is this reasonable? It's a 5 bedroom 2 storey detached house built in 2021. Any got a similar situation with gas CH for comparison?
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