Going Green isn’t easy

[ProfJohnL]

God help you if you get a heat pump.
1) Lot more expensive to run than a gas heating system
2) A lot more costly to repair or replace in 10 years time
3) Dont believe the salesmans bullshit about COPs of 6+ ( they struggle to hit COPs 2 in the middle of winter. )
4) Try getting a quote for annual service compared to a gas service. ( will be 2 to 3 times dearer for the ashp )

It seems you may have decided your opinion about HP's and that is fine as everyone is entitled to make up their own mind, but if your opinion is based on the criteria you have listed, then sadly I have to disagree with those statements and the conclusions you seem to draw from them,

You complain that an HP is "Lot more expensive to run than a gas heating system" that depends on which tariffs are you comparing, and is that comparison over the same environmental conditions? All the published reports show that HP's can be more efficient (energy in to heat energy out) than gas or any other type of heating device.

As for replacement costs in the future, Firstly rather like the dire warnings of EV batteries failing in 5 or fewer years made by the pro fossil fuel lobby, It's too early to predict the failure rates of HP's. Granted that if the present day cost differences between HP's and other heating systems were maintained, then it's possible but not certain that HP's may continue to be more expensive, BUT even if that will be the case, the cost savings of using an HP over a gas or resistive electric heating will offset the present day price differentials, BUT again as HP's become more popular their relative costs will fall, and its highly likely the cost of gas boilers will rise as demand for them drops, so it's highly likely HP's will approach parity with gas boilers in the future.

(additional edit)
Incidentally your fridge and freezer use a heat pump, and they generally run continuously for years with minimal if any maintenance, clearly though, now I have told you that you will be getting rid of both those items of equipment., along with your car if it has air conditioning.

I do agree that a HP's COP of 6 or more is unlikely to be regularly achieved, and that in winter the COP is likely to be lower, but even if falls as low as 2 as you suggest, You seem to ignore the fact that means it is still 200% efficient! Even condensing gas boilers lose some of their high nineties efficiency in winter because the boiler is has to work harder but even the best gas boiler cannot achieve the 200% or more of a HP.

As HP's are very much in the minority at the moment, there are inevitably fewer approved service agents, but as time goes by the number of agents will increase. It is perhaps too early to predict what a realistic service will cost in the future, but the consumer market forces will cause the cost to effectively drop as the number of HP's increases. Will it ever be as low as present day gas boiler services? Probably not but the same market dynamics will probably apply, as more HP services are needed, that means more service providers will be looking for work, and that will naturally for competion and drive service costs dow, and if fewer Gas boiler services are needed it's more likely gas boiler services will cost proportionately more, so HP costs will tend to match G. Boiler costs in the future. I have to stress here the change over is likely to take many decades rather than just one.

Take a look at the many learned reports from well respected organisations that actually put numbers based on scientific studies about the practicalities and both environmental and financial advantages of of heat pumps. There will be some circumstances where a heat pump is not the best solution, but provided the HP can produce the required amount of heat energy a property needs it will almost certainly more energy efficient than any other form of heating. It may need a different approach in the way its used compared to a gas boiler, but that does not mean it does not work.

 

[davyayr]

Interesting post. 👍
Lots of different options. 🤔
The following is just my own opinion although I’m on my 14th house since 1985, and apart from a new build I was in from 2002 a 2007, I’ve installed, replaced or upgraded every system in every house. I’m a DIY’r so gas work is always done by qualified gas engineers. . I’ve also had 7 BTL properties in the same period. Currently 3.
I’ve tried all sorts of traditional options, but never heat pump systems, which for me are a waste of money, currently. I do A LOT of research.
So my thoughts.
Electric systems either panel heaters or boilers. Far too expensive.
Heat pumps…ridiculous break even timescale.
So for me it’s GCH.
Combi boiler without a tank is my go to system, with a Hive or similar controller, for extra control.
Boilers? Had them all.
Despite the good reviews elsewhere , the worst one was a Worcester/Bosch one 🤔
Currently have a 23 yrs old Vokera 29HE in my house. 😮 I’ve been in house for 11 years, get it serviced every year by BG and apart from a PCB board and pump in year 2, covered by contract, it’s never missed a beat.
Still gets a pass on efficiency tests and as long as parts are available, I’m happy.
So to summarise, GHC sealed system for me.
Important to remember is that a salesman will do the BTU. calculations for your house. They will suggest the bare minimum output boiler based on that. Keeps the price down.
My advice. Go for the next boiler output size up and maybe 2 up from salesman recommendations.
Better a boiler easily coping than one that is working at max capacity all the time.
You can have a hotter non powered shower all the time.
Don't you hate turning shower pressure down to get it hot. That because your current boiler can’t cope.
Winter is here and so is mains water temp. 😮

 

[Jcloughie]

Interesting post. 👍
Lots of different options. 🤔
The following is just my own opinion although I’m on my 14th house since 1985, and apart from a new build I was in from 2002 a 2007, I’ve installed, replaced or upgraded every system in every house. I’m a DIY’r so gas work is always done by qualified gas engineers. . I’ve also had 7 BTL properties in the same period. Currently 3.
I’ve tried all sorts of traditional options, but never heat pump systems, which for me are a waste of money, currently. I do A LOT of research.
So my thoughts.
Electric systems either panel heaters or boilers. Far too expensive.
Heat pumps…ridiculous break even timescale.
So for me it’s GCH.
Combi boiler without a tank is my go to system, with a Hive or similar controller, for extra control.
Boilers? Had them all.
Despite the good reviews elsewhere , the worst one was a Worcester/Bosch one 🤔
Currently have a 23 yrs old Vokera 29HE in my house. 😮 I’ve been in house for 11 years, get it serviced every year by BG and apart from a PCB board and pump in year 2, covered by contract, it’s never missed a beat.
Still gets a pass on efficiency tests and as long as parts are available, I’m happy.
So to summarise, GHC sealed system for me.
Important to remember is that a salesman will do the BTU. calculations for your house. They will suggest the bare minimum output boiler based on that. Keeps the price down.
My advice. Go for the next boiler output size up and maybe 2 up from salesman recommendations.
Better a boiler easily coping than one that is working at max capacity all the time.
You can have a hotter non powered shower all the time.
Don't you hate turning shower pressure down to get it hot. That because your current boiler can’t cope.
Winter is here and so is mains water temp. 😮

I do agree. However. I am also pleased that others, that is home owners, institutions, companies and government. Are testing and exploring alternatives in order to develop workable solutions.

As I have already indicated, I feel certain that the way forward is in building design and insulation. Eco houses do exist. And work very well. But at a cost. Not easy when the demand is for cheap starter homes.

Insulating and draught proofing existing housing stock is important. But very limited in what it can achieve.

John

 

[JTQ]

Insulating and draught proofing existing housing stock is important. But very limited in what it can achieve.

And that is a massive problem. In the UK I suspect most people live in a dated property that's poorly suited to significantly and cost effectively change.
We have what we have, selling and buying a new build simply moves it from my problem to another's, I doubt there will be a widespread rip down and rebuild of the UK's housing stock.
Whilst fully supporting a push towards going green the dictates and mandates have to take in the reality of where we are, or face failure.

 

[Jcloughie]

And that is a massive problem. In the UK I suspect most people live in a dated property that's poorly suited to significantly and cost effectively change.
We have what we have, selling and buying a new build simply moves it from my problem to another's, I doubt there will be a widespread rip down and rebuild of the UK's housing stock.
Whilst fully supporting a push towards going green the dictates and mandates have to take in the reality of where we are, or face failure.

Absolutely. And to exacerbate the problem. Poorly trained people and businesses will be selling unsuitable solutions in insulation and heating solutions.

There has just been a report about the ‘government’ funding of insulation and heating payments made. They all come from our fuel bills. But distributed by unregulated businesses. The main driver being profit. Therefore, the effectiveness is very dubious.

John

 

[otherclive]

And that is a massive problem. In the UK I suspect most people live in a dated property that's poorly suited to significantly and cost effectively change.
We have what we have, selling and buying a new build simply moves it from my problem to another's, I doubt there will be a widespread rip down and rebuild of the UK's housing stock.
Whilst fully supporting a push towards going green the dictates and mandates have to take in the reality of where we are, or face failure.

That’s exactly our problem in a mid 1980s house. It’s very well insulated roof, walls, windows and all doors since 2019. Not expensive to heat using a gas vented system. EPC at C. But totally unsuited to heat pump, unvented boiler or combi boiler without significant expense and disruption. The whole development is similarly affected as are many others in the town. We can live with it by replacing the boiler when required, but what about those who come after us with large mortgages and families?

 

[GUMPY]

Poorly trained people and businesses will be selling unsuitable solutions in insulation and heating solutions.

That goes for gas systems as well. I have been told many times it's not possible to run low flow temperature heating using a gas boiler.
I'm at present running weather comp and the flow temp as it's 13deg outside is 42deg, that is a deltaT of 22 or almost heat pump levels. I also run the system 24/7 rather than off at night which I was told was not good. From initial day to day observations it looks like my gas usage is going to be 20% lower. 😱
I do need to change 2 radiators for larger ones but both are in rooms we hardly use.
House is 1985 with reasonable insulation EPC is C it will be B when I get round to insulating the floors.

 

[Jcloughie]

That goes for gas systems as well. I have been told many times it's not possible to run low flow temperature heating using a gas boiler.
I'm at present running weather comp and the flow temp as it's 13deg outside is 42deg, that is a deltaT of 22 or almost heat pump levels. I also run the system 24/7 rather than off at night which I was told was not good. From initial day to day observations it looks like my gas usage is going to be 20% lower. 😱
I do need to change 2 radiators for larger ones but both are in rooms we hardly use.
House is 1985 with reasonable insulation EPC is C it will be B when I get round to insulating the floors.

I also have weather compensation. It was an extra on purchasing the boiler. I could choose a couple of ‘extras’ for a government discount. The compensation works well, but was a bit of a con. It only consists of an outside temperature sensor fed into the boiler. The complicated software bit was already part of the boilers PCB. I realised this when I needed to change the sensor which was very cheap compared to what I paid with the boiler.

I understand what you are doing with the low temp 24/7. Should be nice and comfortable. I have a different approach using smart thermostats on each rad. Each rad can control the boiler. (Not all systems do this and need the boiler pump to run 24/7.

My bills are not as low as some quote. But I like to be comfortable and pay around the national average. About £1800

John

 

[ProfJohnL]

I have to take issue with those of you who are saying a particular building is not suited to a heat pump implying in some way a heat pump would not work within that setting. That is a fundamentally incorrect.

From a purely thermal perspective, a building does not care how the heat is created as long as there is enough heat to meet the demand. If a building needs X kWh of energy to make it comfortable, you could use any form of heating that can supply X kWh of heat.

They type of building does not affect the way a heat pump works only how big the heat pump needs to be. If a building is too draughty, it has the effect on the thermal efficiency regardless of how the heat is produced. Regardless of the source of heat, it is advantageous to reduce draughts and improve insulation.

If you want to reduce the amount of energy you buy for heating, then fitting a heat pump will achieve that, but you will reduce your energy demands if you also optimise the thermal performance of the building with insulation and draught proofing.

There is at present a higher cost to replace GCH system with a heat pump, and that will be an issue for some, but as the UK's use of HP's increases, competition between installers will moderate the cost of HP installs, and at the same time the reduction in GCH install will likely see their price increase, and I anticipate parity or better in the 2030's

 

[otherclive]

I have to take issue with those of you who are saying a particular building is not suited to a heat pump implying in some way a heat pump would not work within that setting. That is a fundamentally incorrect.

From a purely thermal perspective, a building does not care how the heat is created as long as there is enough heat to meet the demand. If a building needs X kWh of energy to make it comfortable, you could use any form of heating that can supply X kWh of heat.

They type of building does not affect the way a heat pump works only how big the heat pump needs to be. If a building is too draughty, it has the effect on the thermal efficiency regardless of how the heat is produced. Regardless of the source of heat, it is advantageous to reduce draughts and improve insulation.

If you want to reduce the amount of energy you buy for heating, then fitting a heat pump will achieve that, but you will reduce your energy demands if you also optimise the thermal performance of the building with insulation and draught proofing.

There is at present a higher cost to replace GCH system with a heat pump, and that will be an issue for some, but as the UK's use of HP's increases, competition between installers will moderate the cost of HP installs, and at the same time the reduction in GCH install will likely see their price increase, and I anticipate parity or better in the 2030's

In actual fact if the home is suitable for a heat pump system it may not cause too much disruption installing one and costs with £7500 government grant can be on a par with a boiler replacement. But if mains inlets are too small, or space for the tanks and pumps etc is at a premium, or internal heating pipework or radiators inadequate your comments fall absolutely flat. As anyone trying to install a grossly oversized heat pump and not addressing the properties shortcomings would probably be significantly worse off than just replacing a boiler and have a sytem that risks providing inferior heating compared to the boiler system. COP means absolutely nothing if the total system isn’t adapted for a heat pump. Thoughts about installing one in a shed where it would cost less to run than a boiler output v output do nothing to address the real issues some home owners and landlords will face.

A heat pump will not function satisfactorily in our property and no amount of oversizing the heat pump would meet its maker’s specifications for installation and performance. For the same reason you would not put a MT30 in to a narrow boat.

 

[JTQ]

I suspect few make the error of believing a HP system can't be specified big enough to replicate say a gas boiler, its self evident if it has the same energy out put it will achieve the same results.

However, the problems come with the costs of buying it, the electric energy to power it, the size of the convectors it needs to dissipate the low quality energy along with environmental impact a large plant running will have. To get the cheaper electrical energy its operation has to be spasmodic, any necessary operation outside the low cost time slots comes presently more expensively than from gas.

In claiming some properties are unsuited for HP systems I have moved on from it being a purely academic assessment to being pragmatic.
The required plant, its bills and its impacts come at simply unrealistic values.
I have a paddock where a large capacity ground heat pump system is totally technical viable, along with no real noise impact to neighbours or ourselves. However, it would be anything but cost effective, nor the upheaval hassle tolerable, more so at our age.
IMO bringing practical issues into the consideration, make my property "unsuitable".
The real problem is the property itself its not optimised for space heating, something I contend most of the UK's aging housing stock shares.

 

[GUMPY]

I also have weather compensation. It was an extra on purchasing the boiler. I could choose a couple of ‘extras’ for a government discount. T

Luckily I knew what the weather comp was and how it worked, which was more than the installer did, before getting the boiler fitted mine was £15 off eBay. Problem I had was getting the hot water interface to work as it uses the HW off line to disable it that should switch between 230v and 0v, unfortunately there was ghost voltage on the line which caused the boiler not to switch. An SSR cured that and now the boiler sees 0v when hot water on and 230v when HW off.

At present boiler consumption is averaging about 2kWh over 24hrs way below it's 15kW rating but it's not actually heating the house now merely replacing heat lost.

Looking forward to a bit of winter, not that it's that bad down here, to see if I got it right.

 

[ProfJohnL]

In actual fact if the home is suitable for a heat pump system it may not cause too much disruption installing one and costs with £7500 government grant can be on a par with a boiler replacement. But if mains inlets are too small, or space for the tanks and pumps etc is at a premium, or internal heating pipework or radiators inadequate your comments fall absolutely flat. As anyone trying to install a grossly oversized heat pump and not addressing the properties shortcomings would probably be significantly worse off than just replacing a boiler and have a sytem that risks providing inferior heating compared to the boiler system. COP means absolutely nothing if the total system isn’t adapted for a heat pump. Thoughts about installing one in a shed where it would cost less to run than a boiler output v output do nothing to address the real issues some home owners and landlords will face.

A heat pump will not function satisfactorily in our property and no amount of oversizing the heat pump would meet its maker’s specifications for installation and performance. For the same reason you would not put a MT30 in to a narrow boat.

Of course when the idea of fitting a heat pump is raised, there has to be a some due diligence to establish the practicality and costs of the idea. Issues such electrical capacity, placement and any ancillary issues need to be sorted, and yes some properties may prove to be unsuited to the installation of a heat pump.

There are also some financial concerns about the higher cost of installing Heat pumps, but point I'm making is that where such issues do arise, it's due to problems with the building and NOT the heat pump.

Not directly related to your particular situation, but if an existing heating system is being replaced and its found a Heat Pump needed to be oversized to continue to heat the building as required, then it does mean he previous heating system must have already been oversized to compensate for the buildings excess heat loss, and that means the owners would have used and paid for more energy than was needed if the building had been optimised. Those losses could have been converted into savings if the insulation etc had been addressed in a timely manner, and then put towards the extra work needed to install a heat pump.

Once installed the heat pump would save energy because of its CoP . Whether that converts to cost saving compared to Gas is difficult to establish becasue of the variances in the energy tariffs, but it definitely saves energy.