Heat Pumps: anyone have one/thought about it?

It isn't looking good for our heat pump install. We had the electrician from Octopus around today and the house fuse (80A) just isn't enough for what we want to do. We have 2x ovens, 2x 8kW electric showers, air con and 5kW hybrid inverter. We also have the EV charger, but that can kick down if the load is too great - which a heat pump can't. Basically it's off to Northern power to see if they'll allow it, but its probably going to be a firm no or insistence on 3 phase, which opens up other issues (cost mainly!). The only other solution is to rip out the electric showers, but I don't fancy having to redecorate two shower rooms! The electrics themselves are a dogs dinner aswell. The consumer unit is full, tricky to access and to compound it all, they can't just go from outside as all the solar electrics are indoors. It would also limit our ability to get an induction hob too unless it was a 13A variant.

Ironically none of this was picked up in the survey, so its a good job I pushed for a visit before signing anything!

We'll see what Northern power say I guess. They don't install 100A fuses normally now, but I'm hoping they will and then it might be okay.
 
My electrics are getting a bit tight, apparently UK Power Networks are still fitting 100A fuses but that depends how I fill out their online questionnaire, otherwise it says I need 3 phase. No electric showers here, but we do have an induction hob and EV charge point. We do get 8kW from the Victron system so that does reduce our grid draw, unless it's charging overnight. But then it would just be the car, Victron and a heat pump. Car and house batteries can limit grid draw.

Had a phone call from Octopus, he implied cost would likely be reduced with a full survey, and they could fit the tank in a 600 x 600 x 2100mm space, and put the buffer tank on the loft. They told me I'd be better off buying from them as they'd still be around in 20 years, I said so will a Valiant installer network even if my installer wasn't!
 
Yes, its pretty annoying as we barely draw anything most of the time. The only heavy draw would be overnight, with 5kW to charge the batteries, the EV charger (which throttles anyway) and perhaps the dishwasher. We've never seen much above 10kW as we try to avoid grid use as you'd expect. The problem is they do a max load test, which for us is quite ridiculous. 2x 8kW showers, 2x 3kW ovens, 5kW inverter = 27kW or 117amps! It would never happen in a million years, but its the regs so there we go. :rolleyes:

Honestly its very silly. We're in a 6 year old house yet even that is a nightmare for a heat pump. Just how do they expect everyone to get heat pumps, solar and EV chargers when the infrastructure isn't able.
 
The max load test was recently revised to take into account no one turns on everything at the same time.

The chance of two electric showers going and two ovens and your heat pump going full tilt all at the same time is laughable really.

You are not going to charging batteries from peak time electricity so that can be canned and you aren’t going to be cooking in the middle of the night on 2 ovens (or showering X2) when the car and batteries are charging.

The hybrid inverter should be reducing peak grid load, not adding to it.

The issue with these tests is that they often lack common sense.

Edit: that said, canning the electric showers isn’t a bad thing, mains pressure hot water through a mixer shower is far far superior.
 
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Yes, we only use one of the showers and one of the ovens. They are never used when the battery or EV are charging as that is overnight. We also never use the showers and ovens at the same time.

It's utterly ridiculous.
 
This is one of those areas where the octopus approach falls a bit short as the surveyors are not experienced installers.

I’d suggest speaking to them once you get the quote back as you’ll likely get more sense from the technical team.
 
Ok, so I’ve been playing about with ours.

Heating up the whole of downstairs with underfloor gas heating is working out far far more expensive versus taking the edge off the cold with the cheap overnight EV and then just heating the rooms we use with the heat pump in the day, often switching it off once up to temperature.

The biggest problem is that our biggest multi split heat pump is on the bedroom wall and on full heating mode can be heard through the wall. I’d get them fitted to the ground if doing it again. The smaller units are fine. So I’m not able to use the big unit overnight as much as I hoped.
 
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Got my quote from SGS Energy today, after taking off the BUS grant it is a few quid under £5000, we're OK with that. Its an Vaillant aroTherm+ 7kW along with the uniTower, no radiator upgrades required, just the removal of the existing zone valves.

It may seem a lot, especially compared to the quote above, but its also £3.2k cheaper than another local installer for the same system, and much cheaper than others I've seen. It is a local installer, so hopefully we will get a better install, its also using a Vaillant uniTower, which adds about £1000 to the cost over a more usual setup, the flip side is this should be a much neater and more compact install.
 
I noticed that mortgage lenders offer 0% for things like heat pumps and double glazing.

Might be something to check out if anyone was unaware.
 
Stu999 said:
What do you mean exactly?
Click to expand...

Green Additional Borrowing | Nationwide

Need help funding your home energy improvements? Nationwide’s 0% interest Green Additional Borrowing deal could help. Terms and Eligibility apply.
www.nationwide.co.uk www.nationwide.co.uk

Means you could remortgage to get money for heatpump or whatever and pay back over 5 years which might make it a good idea for some. Could just keep cash in a decent interest saving account and then pay the mortgage interest free.
 
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Hedge said:

Green Additional Borrowing | Nationwide

Need help funding your home energy improvements? Nationwide’s 0% interest Green Additional Borrowing deal could help. Terms and Eligibility apply.
www.nationwide.co.uk www.nationwide.co.uk

Means you could remortgage to get money for heatpump or whatever and pay back over 5 years which might make it a good idea for some. Could just keep cash in a decent interest saving account and then pay the mortgage interest free.
Click to expand...
That is interesting, haven’t heard of a product like that before.
 
b0rn2sk8 said:
The max load test was recently revised to take into account no one turns on everything at the same time.
Click to expand...

This has been a thing for a long time, certainly in kitchens.at least anyway, They take into account diversity of the power as nothing draws max current/power all of the time, it would generally be max only for a short period.
 
Stu999 said:
What do you mean exactly?
Click to expand...
Nationwide will give a 0% loan as long as you have a mortgage, some banks will even give you £2000 back.

This blog may be out of date, but worth checking.

octopus.energy

Save on solar and heat pumps with cashback from your bank

Want to get solar panels or a heat pump but not sure you can afford it? Good news: depending on who you bank with, you could get up up to £2,000 cashback to kickstart your transition to clean, green energy.
octopus.energy octopus.energy
 
reef said:
Yes, its pretty annoying as we barely draw anything most of the time. The only heavy draw would be overnight, with 5kW to charge the batteries, the EV charger (which throttles anyway) and perhaps the dishwasher. We've never seen much above 10kW as we try to avoid grid use as you'd expect. The problem is they do a max load test, which for us is quite ridiculous. 2x 8kW showers, 2x 3kW ovens, 5kW inverter = 27kW or 117amps! It would never happen in a million years, but its the regs so there we go. :rolleyes:

Honestly its very silly. We're in a 6 year old house yet even that is a nightmare for a heat pump. Just how do they expect everyone to get heat pumps, solar and EV chargers when the infrastructure isn't able.
Click to expand...
There are standard calcs for load diversity, as an oven will cycle once at temp for example. Should all be specified.
 
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reef said:
It isn't looking good for our heat pump install. We had the electrician from Octopus around today and the house fuse (80A) just isn't enough for what we want to do. We have 2x ovens, 2x 8kW electric showers, air con and 5kW hybrid inverter. We also have the EV charger, but that can kick down if the load is too great - which a heat pump can't. Basically it's off to Northern power to see if they'll allow it, but its probably going to be a firm no or insistence on 3 phase, which opens up other issues (cost mainly!). The only other solution is to rip out the electric showers, but I don't fancy having to redecorate two shower rooms! The electrics themselves are a dogs dinner aswell. The consumer unit is full, tricky to access and to compound it all, they can't just go from outside as all the solar electrics are indoors. It would also limit our ability to get an induction hob too unless it was a 13A variant.

Ironically none of this was picked up in the survey, so its a good job I pushed for a visit before signing anything!

We'll see what Northern power say I guess. They don't install 100A fuses normally now, but I'm hoping they will and then it might be okay.
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It was northern power grid I had to deal with in regards to my looped supply.

Could they not just upgrade the fuse to 100amp like they did with mine or would that still not be enough.

My supply feeds 4 house each with ovens and electric showers, and my neighbour's massive hot tub in the garden. They upgraded the cut outs and fuses for each house in the loop and Gave the go ahead for my heat pump and solar.
 
There is a bit of a push to stop upgrading people to 100 amp fuses, with 80 being the max and the preference above that is for 3 phase.

The document is published by National Grid, and came into effect in June 2023, it even goes as far to state that 100 amp fuses may be down graded to 80 amp. I've no idea how strict DNO's are though, and every DNO could be different.

Obviously 100 amp fuses are still being fitted, and it looks like UKPN will still fit a 100 amp fuse, but this document suggests change could be coming, but then changing to 3 phase would be far too expensive for most end users, perhaps that does affect policy.

https://www.nationalgrid.co.uk/downloads-view-reciteme/633928

.
 
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ci_newman said:
I had a desktop quote come back from Octopus at £800 fitted after grant. My gas C/H system works fine, but that's damn tempting whilst the grants are available
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Will depend on house size, age, location and construction the below were the potential additional costs for a 2 bed mid-terrace in my case

EPC grant £65+
Asbestos test £200
Planning Permission (noise only now) £320
Structural Survey £500+
Groundworks £500+
 
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