Heat Pumps: anyone have one/thought about it?

[Mercenary Keyboard Warrior]

That's a bit rubbish isn't it. 5 years is that all they reckon it'll last before failure on average.
Makes it even worse Vs boilers with 10 year warranties.

I dunno I mean most boilers are in fact 5 years (WB, Valliant, ideal for example) but can go to 7-10 based on criteria, normally also insisting on an over priced annual service.

Its quite possible the same applies to these. In fact it sounds like the same must be serviced type guff as well. Not really surprising they all try it on now.
Says 7 on hybrid if installer by approved, assume these would be hybrid as water and heat but not sure tbh.

No idea on real lifetime it certainly won't be forever. My experience at work with AC units (closest I can think of) is that all the ones we change tend to be older, and the parts they normally say are busted are compressors and pumps. Both in theory quite cheap parts but generally no longer available by the time the units break or just not cost effective to start messing about with.
The good thing should be that as they are far less safety critical once a decent second hand refurbishment type setup happens they should be easy and quick fixes. The problem with boilers from my experience is that the bits that start to fail once they are a little older are either OOS or silly expensive from the only source, the OEM.

 

[fish]

a welcome increase

 

[b0rn2sk8]

I dunno I mean most boilers are in fact 5 years (WB, Valliant, ideal for example) but can go to 7-10 based on criteria, normally also insisting on an over priced annual service.

Its quite possible the same applies to these. In fact it sounds like the same must be serviced type guff as well. Not really surprising they all try it on now.
Says 7 on hybrid if installer by approved, assume these would be hybrid as water and heat but not sure tbh.

No idea on real lifetime it certainly won't be forever. My experience at work with AC units (closest I can think of) is that all the ones we change tend to be older, and the parts they normally say are busted are compressors and pumps. Both in theory quite cheap parts but generally no longer available by the time the units break or just not cost effective to start messing about with.
The good thing should be that as they are far less safety critical once a decent second hand refurbishment type setup happens they should be easy and quick fixes. The problem with boilers from my experience is that the bits that start to fail once they are a little older are either OOS or silly expensive from the only source, the OEM.

Octopus quote up to 20 years, I'm dubious but then my boiler is 20 years old and still running. I'd expect it would at least need a new fan in that time but the cost of that should not be significant.

The best part a about a heat pump is that once all the remedial work is done to your property, you don't need any certificates to work on it or even replace it at end of life. You can do it yourself if you are that way inclined.

 

[China Man]

My survey is planned in October, I wonder if my install will be cheaper now that gov is putting up the grant to 7500...

 

[fish]

snap, thats what i am hoping

 

[HungryHippos]

I don't really see how it can be any other way... but remain intrigued as to what the total cost would be.

I'm sure survey may flag a few bits and pieces, but if I could get heatpump installed for £1K then that is a steal in my view.

 

[b0rn2sk8]

I have just paid my £500, I was holding off until after I get solar installed but I'm not one to look a gift horse in the mouth.....

This grant has a set budget, is first come first served and once the money is gone, its gone. It will be end or be reduced with days or weeks of notice (see EV and charger grants).

EDIT: I just looked at the department for energy's website and they have not published any documents today, I'm sure it will come out in the coming days and gov.uk updated to confirm when the £7500 starts. I'd expect it will be based on installation date i.e. from today.

 

[dirtychinchilla]

That increase from 5k > 7.5k is going ti screw up all the individuals, including me, who only recently got an Octopus quote! I'm pretty sure they will not accept a further 2.5k reduction in the provided quote without a means or method for them to skim

I got quoted £3k the other day. If that's now going to drop to £500, I'll probably just go for it next year for the excitement of owning a heat pump. I imagine I'll see marginal gains as far as energy bills are concerned, though I could drop the gas hob and go induction for the small standing charge benefits I suppose.

 

[robj20]

I got quoted £3k the other day. If that's now going to drop to £500, I'll probably just go for it next year for the excitement of owning a heat pump. I imagine I'll see marginal gains as far as energy bills are concerned, though I could drop the gas hob and go induction for the small standing charge benefits I suppose.

Good point actually if I went heatpump, I could do away with gas completely.
A tank could I guess go in the garage with moving a few things around. I slim but tall one might fit.

Filled in octopus online quote see what it says.
Interesting my property is C rated.
If that was when it was first done we've had new windows and doors since and new loft insulation so probably a B now.

 

[robj20]

Done some maths this morning so far my gas usage is at 4112kwh (£513) and electric 2412kwh (£937) for the last 12 months.

Of which £100 of the gas is standing charge so straight away I'd save that.

COP of 2.5 (not sure how realistic that is)

Using today's rates 4112*£0.075=£308(gas)
Heatpump
4112/2.5=1645kwh(elec)
1645*£0.2994=£492.

Is my maths wrong or is it just not worth it? About £90 a year worse off after removing gas standing charge as well.

 

[darkgen]

Likely not. Remember ASHP are supposed to be more efficient, not necessarily cheaper (when compared to current gas costs). Although; the real test is when the thing is actually used to generate heat in the coldest of months when it is likely to pull more electricity to heat when the efficiency calculations drop off a cliff. I'd like to see how well it performs in comparison to a gas combi over a quarter period, say between December - February.

 

[200sols]

Is my maths wrong or is it just not worth it? About £90 a year worse off after removing gas standing charge as well.

Maybe not wrong, higher efficiency doesn't mean cheaper to run. But remember you can take advantage of smart tarrifs e.g octopus cosy offers cheap rates twice a day 6 hours total at 18p.

 

[b0rn2sk8]

The cheapest ultimately depends on the cost difference between electricity and gas.

If electricity costs more than 4 times gas, gas will be cheaper. If it costs less than 4 times gas, electricity will be cheaper.

This assumes a 300% SCOP and average boiler efficiency and the loss of the standing charge.

Although; the real test is when the thing is actually used to generate heat in the coldest of months when it is likely to pull more electricity to heat when the efficiency calculations drop off a cliff. I'd like to see how well it performs in comparison to a gas combi over a quarter period, say between December - February.

performance is measured as an average across the year. So the quoted SCOP includes winter and it is based on when you actually use heating E.g. the majority of the energy being used in winter.

Performance reduces on the coldest winter days, ‘it doesn’t fall off a cliff. It’s really not that dramatic….

 

[HungryHippos]

Is my maths wrong or is it just not worth it? About £90 a year worse off after removing gas standing charge as well.

Gas isn't 100% efficient, if it was then the usage would have been a bit less for the same heating on the gas supply.

I think if you had an ASHP you'd probably be wanting to consider the Octopus Cosy tariff over the winter.

Cosy Octopus

The UK's most awarded energy supplier. We're doing energy better - for you and the environment.

octopus.energy

Day rate:

30.3p / kWh​

Cosy rate (04:00 - 07:00 & 13:00 - 16:00):

18.18p / kWh​

Peak rate (16:00 - 19:00):

48.47p / kWh​

Standing charge:

47.95p / day​

The peak rate is very expensive of course, but if you are heating on full blast for the 2 x 3 hour cheaper periods, then enough of a load shift that way will reduce your average price paid per kWh.

 

[robj20]

Gas isn't 100% efficient, if it was then the usage would have been a bit less for the same heating on the gas supply.

I think if you had an ASHP you'd probably be wanting to consider the Octopus Cosy tariff over the winter.

Cosy Octopus

The UK's most awarded energy supplier. We're doing energy better - for you and the environment.

octopus.energy

Day rate:

30.3p / kWh​

Cosy rate (04:00 - 07:00 & 13:00 - 16:00):

18.18p / kWh​

Peak rate (16:00 - 19:00):

48.47p / kWh​

Standing charge:

47.95p / day​

The peak rate is very expensive of course, but if you are heating on full blast for the 2 x 3 hour cheaper periods, then enough of a load shift that way will reduce your average price paid per kWh.

You're right I hadn't considered gas efficiency I will factor in a realistic 70% not the silly quoted 95% or what ever they make out it is.

Is the COP of 2.5 realistic in the UK?

 

[b0rn2sk8]

SCOP of 3 is more than realistic for a retrofit. 4+ is easily achievable if starting from scratch on air source.

I wouldn’t entertain a SCOP of less than 3 personally. It should be higher.

I’d also use 85% for a boiler.

 

[HungryHippos]

Think it only drops when it's really cold, which is kind of a negative because that's also when you want it on.

When temps are below freezing will be interesting to see how well it works.

 

[b0rn2sk8]

Plenty of information out there from owners:

Heat Pumps In Winter ££££!!! - The Running Costs!

You could hate or like heat pumps but the one constant in the comments section is that most are wanting to know how much it has cost us to run over the winte...

youtu.be

Heat Pumps, Hot Water & Electric Usage!

Quick video about how my heat pump works with hot water and the immersion heater that many think is needed.Website: www.ev-man.co.ukTwitter: https://twitter....

youtu.be

 

[robj20]

SCOP of 3 is more than realistic for a retrofit. 4+ is easily achievable if starting from scratch on air source.

I wouldn’t entertain a SCOP of less than 3 personally. It should be higher.

I’d also use 85% for a boiler.

It's not 85% as I have reduced my temps to save money it's made the boiler less efficient. Suits around 68 on mild days to about 77 on colder days.

 

[jpaul]

Is my maths wrong or is it just not worth it? About £90 a year worse off after removing gas standing charge as well.

How/did you split out domestic hot water gas use versus heating gas, for that higher temp heat pump water may need an electrical boost,
the evolving heat pump technology with higher temp versions in the pipeline is one of the dilemmas for deciding to engage.