Are we targeting ASHP's at the wrong market?

[joth]

I agree with the gist of the OP, but the discussion brings to mind a few general comments

 

1/ Beware of creating false dichotomies. 

Yes, we should be targeting homes already on resistive electric heating for upgrade to heat pumps, but that doesn't mean we shouldn't also be targeting homes combusting fossil fuels too. Both need to happen, and technically there's no reason both can't happen at once.

 

2/ Keep an eye on the long term goal.

Sure replacing one boiler with a heat pump will not reduce scope 2 emissions for that home's heating to zero today, but the goal is net zero by 2050, not today. If it's a step towards that goal it's a step worth seriously considering. 

 

3/ Massive scale systems change is required, not tinkering at the edges.

This is a multi industry, multi decade project. Optimising each individual's personal emissions at every single step is not practical or in fact useful. What's important is on average everything trends towards net zero. Regrettable as it is, there will be examples of houses making nonoptimal choices that taken in isolation can be seen as a back step, but by moving towards renewable heat sources they are still support the systems changes needed; e.g. directing more of their ongoing spending away from gas and into electricity (and hence renewable generation projects), and supporting the economies of scale needed to reduce the cost of materials and increase training & knowledge in heat pumps.

 

[ProDave]

52 minutes ago, G and J said:

 

So (19% + 17% + 22% + 31% + 50% + 74% + 15% + 17% + 2% ) = 278% of homes aren’t suitable for a heat pump.  Crumbs.

 

I’m no mathematician, but that seems a lot. 😉 

 

I think we need to demolish more buildings or accept slow progress towards net zero.

 

someone needs to work out a venn  diagram of how they overlap?

1 hour ago, Alan Ambrose said:

OK, some stats:

 

+ 19% of homes are privately rented, 17% 'socially rented', that's 36% i.e. ~1/3rd of homes where the landlord would have to pay for the installation (including a rental void period) with the financial benefit of lower heating costs accruing to the tenant. That going to happen very rarely.

+ overlapping with that, 22% of dwellings were flats. Yeah, realistically impossible for flat owners to install ASHPs.

+ overlapping with that, 31% of dwelings in UK have no EPC rating (only required since 2007). We can reasonably conclude that they are mostly old enough to have sub-standard insulation and therefore not suitable for an ASHP.

+ overlapping with that, about 50% of homes that have EPCs are D or below and are probably not suitable for ASHPs.

+ overlapping with that, 74% of households use gas (plus 5% using oil) and therefore don't have any financial incentive to change.

+ of houseowners, 15% of private owners without mortgages are poor (Joseph Rowntree Foundation) and 17% of those with mortgages i.e. they don't have enough money to invest.

+ 2% of homes are listed and there are 10,000 conservation areas - both of which are either unsuitable or impossible to swap to an ASHP.

 

+ we don't have any idea how all those segments overlap, but just from EPC ratings (or lack of them) 2/3rds of dwellings are not suitable for heat pumps, 3/4 have gas already and no incentive to change. (EPCs are, of course, nonsense anyway as the main insulation areas (roof, floor, walls) may just be 'assumed'.)
 

+ plus it requires personal energy, money, time and the ability to endure the disruption and uncertainty that installation of an ASHP would require. You may also have to battle at your expense with the planners, who have no incentive to be reasonable.

+ many people may just be sitting on the fence as they know that government doesn't always get it right (viz. diesel cars); technology may improve, installers may be better skilled etc.
 

 

 

 

 

 

 

Excellent summary.  Shame the people that write our net zero plans don't bother to analyse the real situation and work out that their plan can never work.

[SteamyTea]

6 hours ago, ProDave said:

each 1kWh of electricity saved at the moment is 1kWh less generated by fossil fuels.

Except about half our electricity come from hydro  nuclear, wind and solar. Some comes from biomass and waste, but that is as bad as coal burning.

 

5 hours ago, Beelbeebub said:

As storage heaters are notoriously uncontrollable

No they are not.

The users are uncontrollable.

Nearly all the ones I see have the input and the output set to maximum, and the users say the house is too hot in the morning and cold in the evening.

 

The problem I have is that I need planning consent, which I would probably get, but the big problem is that I use about 1 MWh/year for space heating. That is about £150/year. DHW is about £225/year.

I hope to move in less that the ten years it takes to hit break even.

 

[PhilT]

2 minutes ago, SteamyTea said:

I use about 1 MWh/year for space heating. That is about £150/year.

 

out of interest, how do you achieve that?

[MikeSharp01]

7 minutes ago, PhilT said:

out of interest, how do you achieve that?

Now we are in for it....

[SteamyTea]

Just now, PhilT said:

out of interest, how do you achieve that?

By banishing parasite loads, reducing the 7 hour window down to effectively 2 hours, keeping DHW temperature as low as practicable, no tumble drying, and constant monitoring.

Yesterday I used 14 kWh, 4 more than my target. But I was in a lot yesterday and used a fan heater (been to mild to turn heating on as only had the odd couple of cold days).

Not unusual in the non winter times to use less than 4 kWh/day.

 

I do live alone which helps, and my house is small.

 

An A2AHP would be great for space heating, and an EAHP for water heating might fit.

Fitting 2 to 3 kW_p of PV is probably the cheapest option for me, even with the compromised roof angles.

[ProDave]

4 minutes ago, SteamyTea said:

I do live alone which helps, and my house is small.

And attached.  and in a mild climate.

 

Your challenge:  Achieve that low usage in a detached house in the Highlands, where tomorrow it is forecast to just creep above 0 for the first time in 2 weeks and has been down to -12 in that time.

 

I often speculate just how low my heating bill would be if i had built an identical house in your climate.  I am using 1400kWh per year here for heating but because none of that is off peak, all standard rate that's just over £300 per year for heating.

[SteamyTea]

1 minute ago, ProDave said:

 

Your challenge:  Achieve that low usage in a detached house in the Highlands

Probably can't be done realistically.

 

It has been, untill the last few days, but exceptionally mild this winter.

And last winter, and the one before.

 

It would be fun to build a house down here that is truly off grid and zero combustion.

But no one is going to give me a £1m to try it out.

£1m would buy 2/3^rd of a 1MW wind turbine, so producing about 2 TWh of electricity a year. Or enough to power 650 houses like mine.

 

[Beelbeebub]

2 hours ago, Alan Ambrose said:

OK, some stats:

 

+ 19% of homes are privately rented, 17% 'socially rented', that's 36% i.e. ~1/3rd of homes where the landlord would have to pay for the installation (including a rental void period) with the financial benefit of lower heating costs accruing to the tenant. That going to happen very rarely.

+ overlapping with that, 22% of dwellings were flats. Yeah, realistically impossible for flat owners to install ASHPs.

+ overlapping with that, 31% of dwelings in UK have no EPC rating (only required since 2007). We can reasonably conclude that they are mostly old enough to have sub-standard insulation and therefore not suitable for an ASHP.

+ overlapping with that, about 50% of homes that have EPCs are D or below and are probably not suitable for ASHPs.

+ overlapping with that, 74% of households use gas (plus 5% using oil) and therefore don't have any financial incentive to change.

+ of houseowners, 15% of private owners without mortgages are poor (Joseph Rowntree Foundation) and 17% of those with mortgages i.e. they don't have enough money to invest.

+ 2% of homes are listed and there are 10,000 conservation areas - both of which are either unsuitable or impossible to swap to an ASHP.

 

+ we don't have any idea how all those segments overlap, but just from EPC ratings (or lack of them) 2/3rds of dwellings are not suitable for heat pumps, 3/4 have gas already and no incentive to change. (EPCs are, of course, nonsense anyway as the main insulation areas (roof, floor, walls) may just be 'assumed'.)
 

+ plus it requires personal energy, money, time and the ability to endure the disruption and uncertainty that installation of an ASHP would require. You may also have to battle at your expense with the planners, who have no incentive to be reasonable.

+ many people may just be sitting on the fence as they know that government doesn't always get it right (viz. diesel cars); technology may improve, installers may be better skilled etc.
 

 

 

 

 

 

 

You assume just because a property is ranked D or lower it is unsuitable for a HP.

 

But neglect that if a property is electrically heated it drops several (about 2) categories vs gas.

 

We have gone from E to C simply by swapping to gas.

 

So there will be a plenty of perfectly suitible homes ranked D or E simply because they are using storage heaters.

 

Just looked up 2 flats of ours. Identical except one has electric heating and the other gas combi

 

Electric scores 40 points E

Gas scores 65 points D

Edited 8 hours ago by Beelbeebub

[Crofter]

I question the whole 'only well insulated homes can use heat pumps' argument.

My house is very, very far from well insulated, nor is it in any sense airtight. And it's working very well with a heat pump. 

I can see why flow temperature and delta T has an impact, with a wet system, but that will hurt a gas or oil system too. And it's irrelevant to an A2A system.

[Alan Ambrose]

Yeah, we don't have the detailed data to come to a firm conclusion (e.g. private houses & low EPC & not-listed vs. social renters & high EPC & in a conservation area etc.) But it's reasonable to think that most places heated by electricity might realistically have heat pumps as long as they're not (a) rented or (b) flats or (c) have a high EPC and low energy usage already, or (d) listed or in a conservation area and (e) where the owners are wealthy enough and have the time and energy to put up with the disruption and (f) don't intend to move with a few years and (g) are prepared to take the leap of faith that (i) the government won't suddenly change the rules around and (ii) the structure of the power markets won't change substantially for the life of the heat pump investment.

 

That's a lot of ifs and buts, and I think an explanation why HP take-up isn't high even amongst the people who might benefit most from it. The 'analysis' isn't rocket surgery .

Edited 8 hours ago by Alan Ambrose

[Beelbeebub]

1 hour ago, ProDave said:

someone needs to work out a venn  diagram of how they overlap?

Excellent summary.  Shame the people that write our net zero plans don't bother to analyse the real situation and work out that their plan can never work.

M y OP was trying to illustrate (albeit with a very simplistic test) that even a homethee is superficially "not possible" to convert to HP could be heated with the low flow required.

 

Obviously upgrading the windows and incrwqcing insulation would help reduce bills and also reduce the size of the required HP.

 

But they aren't necessary.

 

You will get a greater carbon reduction (for the same running cost) by switching to a well sorted HP now than insulating and still running a gas boiler.

 

Of course we should also be insulating. It's not either or.

 

[Beelbeebub]

2 hours ago, ProDave said:

overlapping with that, 74% of households use gas (plus 5% using oil) and therefore don't have any financial incentive to change.

This is a root cause of reluctance. Gas is cheap vs electricity.

 

If the ratio was 1:1 people would be ripping out gas boilers so fast the scrap yards be overwhelmed.

 

If the ratio was 2:1 or even 2.5:1 it wouod be simple to break even vs gas. At the current 3-4:1 range it's hard.

 

Shifting a load of the green and social taxes onto has would help.

 

Reforming the energy market to get rid of the "last unit sets price" method would be a huge win for electricity.

[Beelbeebub]

2 hours ago, ProDave said:

+ 19% of homes are privately rented, 17% 'socially rented', that's 36% i.e. ~1/3rd of homes where the landlord would have to pay for the installation (including a rental void period) with the financial benefit of lower heating costs accruing to the tenant. That going to happen very rarely.

This is an issue with almost any improvement to the fabric of the building.

 

Basically tenants don't seem to care about the EPC.

 

We have almost never had anybody ask about the heating or epc. It was a bit depressing as we'd spend money insulating lofts etc and all anybody was impressed with were the sodding bathrooms.

 

That has changed a bit recently butnit still seems not to be a priority

 

Some of that may be simple pressure on spaces. Competition for homes is so fierce that people are glad to get anywhere even if it is costly to run.

 

Building better social housing to rent wouod go someway to moving the market.

[Alan Ambrose]

>>> Reforming the energy market to get rid of the "last unit sets price" method would be a huge win for electricity.

 

Something I've seen referred to bit on 't 'ub together with its relationship to gas prices rather than, say, PV prices. Possible to explain a bit?

[LnP]

6 hours ago, Alan Ambrose said:

 

+ overlapping with that, 31% of dwelings in UK have no EPC rating (only required since 2007). We can reasonably conclude that they are mostly old enough to have sub-standard insulation and therefore not suitable for an ASHP.

+ overlapping with that, about 50% of homes that have EPCs are D or below and are probably not suitable for ASHPs.

 

The Electrification of Heat Project looked at this. They concluded, "There is no property type or architectural era that is unsuitable for a heat pump ...From Victorian mid-terraces to pre-WWII semis and a 1960s block of flats – the project has proven that heat pumps can be successfully installed in homes from every style and era".

 

Although it's probably true to say that the less well insulated the house is, the worse the economics will be. It probably depends on your definition of suitable.

[G and J]

3 hours ago, Beelbeebub said:

Basically tenants don't seem to care about the EPC.

Methinks the majority of those seeking to rent a property have other things on their minds.

 

3 hours ago, Beelbeebub said:

Building better social housing to rent wouod go someway to moving the market.

We’re not building anywhere near enough, perhaps if we were and supply was closer to demand then tenants would have the opportunity to be more discerning. 

[Beelbeebub]

3 minutes ago, G and J said:

Methinks the majority of those seeking to rent a property have other things on their minds.

 

We’re not building anywhere near enough, perhaps if we were and supply was closer to demand then tenants would have the opportunity to be more discerning. 

Yes, partly this. Although I do also think that until recently people just didn't care as a rule.

 

[G and J]

3 minutes ago, LnP said:

 

The Electrification of Heat Project looked at this. They concluded, "There is no property type or architectural era that is unsuitable for a heat pump ...From Victorian mid-terraces to pre-WWII semis and a 1960s block of flats – the project has proven that heat pumps can be successfully installed in homes from every style and era".

 

Although it's probably true to say that the less well insulated the house is, the worse the economics will be. It probably depends on your definition of suitable.

Maybe I’ve got the wrong end of this one, but I’m thinking…

 

Any property could work out with an ASHP with the right heat emitters, be that large rads or UFH.

 

The most common heating system is gas with rads designed first high flow temperatures. 
 

Replace a gas boiler with an electric heat source providing a high flow temp will increase bills (be it resistive or heat pump based).

 

Expecting peeps to replace working rads just to enable them to spend yet more capital to save the planet a little bit is rather hopeful.

 

So….  hoping for wholesale voluntary transfer to electrical based heating is not going to work. How about we think about banning new houses having gas boilers and we accept slow change….  Oh, they tried that one then worried about re-election.  Sigh.

[Beelbeebub]

1 hour ago, Alan Ambrose said:

>>> Reforming the energy market to get rid of the "last unit sets price" method would be a huge win for electricity.

 

Something I've seen referred to bit on 't 'ub together with its relationship to gas prices rather than, say, PV prices. Possible to explain a bit?

The way the wholesale price per unit is set like auction.

 

The network requests X Mwh and various generators put up bid to supply some Mwh at a set price.

 

The network then accepts the bidsfrom lowest rom lowest nit upwards until it's got enough.

 

So far so normal.

 

But the wrinkle is, the prove paid per Mwh *to everybody* is the price of the last unit bought ie the most expensive.

 

Let's say in a simple setup 1000mwh is asked for.

 

Solar bids 300mwh at £100

Wind bids 300mwh at £150

Gas bids 400mwh at £200.

 

The total cost for the 1000 will be £200,000 not (as you might expect) £155,000

 

That is super simplified but is the rough outline of how it works.

 

 

 

[Beelbeebub]

The other bit is the "green taxes" (a crap name) that pay for stuff like insulation upgrades, social tariffs.for struggling customers, historical subsidies for wind and solar (but not new ones) all tend to go onto electricity prices rather than gas prices.

 

So when there are grants for insulating lofts - that's paid for out of electric prices not gas.

 

Thry aren't huge, a few pence per unit but if we took 2p.from the 23p electricity unit cost and added it to the 5p gas cost we'd have 21p vs 7p so you need a 3:1 efficency to break even (fairly doable) rather than 4.5:1