Wild ASHP running costs...

[Mulberry View]

We follow loads of self-build accounts on Instagram (we're @selfbuild_mulberryview if there are any Instagrammers on here).

 

We've seen a few worrying posts from fellow self-builders who are now in their new home but experiencing very high ASHP running costs. One in particular is a Nudura build, lots of insulation and very airtight. Their 2-month electricity costs for November and December were in the order of £800-900. There are others in the same boat. Granted I don't think they have PV, but that can't be accounting for all of that?

 

We are at a point where we can still change our strategy, so what's the deal here? We could go GSHP, but would need vertical bores. I know that's very expensive, but would it be a smart thing to consider?

 

For reference, the house is about 200sqm.

[JohnMo]

To many variables to comment on, the house may be huge, the heat pump huge, setting everything at high temps, loads of zones, heat pump cycling, poorly commissioned.  Do the same with gshp you would get a similar outcome.

 

PV in winter output is the just about zero anyway, so will have little or bearing on monthly heating bills.

 

Many on here get excellent cost effective heating from an ASHP. Mostly down to how you set things up and operate, keeping flow temps as low as practical.

 

[Kelvin]

Also GSHPs are very expensive to install and probably similar running costs to an ASHP. In theory they ought to be more reliable over their lifetime than an ASHP. I briefly looked into it and it was going to cost circa £28,000 to fit one. 
 

There is little doubt that a poorly designed/installed ASHP that isn’t setup correctly is expensive and your average punter has no chance to understand any of what’s needed to fix it. 

Edited January 23, 2023 by Kelvin

[ProDave]

Well at the other end of the spectrum, our ASHP consumes about 1200kWh per year heating our 150 square metre house in the Highlands and another 1030kWh heating DHW so a total heating bill about £624 per year.  I do wonder why some with what should be well insulated houses have such high usage.  I often wonder just how low our bills would be if we had built the identical house somewhere less cold that the Highlands.?  There are plenty of people with lower heating bills than ours.

[SteamyTea]

I think part of the problem is that people treat it like old fashioned gas heating. Turn it on for a couple of hours at full power, turn it off, then hours later, pull power again till bedtime.

Going to be hard for people to realise that has never been a good way to heat a house, but 50 years if it being the norm is going to take some changing.

 

I could drain my car fuel tank in less than 2 hours at maximum speed, and only go about 180 miles, or I can run it for 12 hours and do over 700 miles. 

Start and end points have not moved.

Edited January 23, 2023 by SteamyTea