Going Green isn’t easy

[otherclive]

I'm sorry Dusty but you have succumbed to the misunderstanding which has arisen around heat pumps. The type and construction of a building does not reduce the efficiency of a heat pump, in exactly the same way they would not affect the efficiency of a gas boiler or electric radiator. They type of building affects how well any heat put into the building is retained and how effective that heat is, but it does not affect the the efficiency of the appliance itself.

I think you are consistently reading HP as just the equipment itself. As myself, Dusty, JTQ, Gumpy, JC and others have indicated it’s the total system installation, which includes the house, that should determine the viability and efficiency of a heat pump installation. I think by now everyone is well aware that as a single piece of equipment a heat pump is more efficient than a gas boiler, your shed analogy explained that. But I venture to suggest that few if any existing houses built before 2000 could just swop a boiler for heat pump without substantial expense and disruption. If they did so, there’s a significant risk that the HP system would fail to meet expectations.

 

[Oscarmax]

I managed to get a grant for my Solar Thermal panels but nothing available to me now.

As for running it on an EV tariff I would need to buy an EV and at least double my battery capacity to cover the daytime, that's over £5k for the battery and inverter to do it.
Its all possible here and I have the knowledge and tech ability to make it happen but financially it's just not worth it and I can't afford it.
There are grants available but I believe you have to be on a benefit of some kind, complete solar, battery and heat pump cost of £40k was the last install I heard about. However it was badly done and they struggled to get the company to fix it.

Admission time: at present my average unit cost is 10.24p over the last 12 months, but that's because I never use electricity during the day relying on Solar and the lower 🐙 Agile prices during the night to charge the battery which has a >24hr runtime

We would happily change to a heat pump, if was a like for like, however even though our bungalow was a new build in 2017, the heating system uses 10mm push fit microbore. We have 4.4 kWh solar panels a 5.8 kWh battery and on Octopus Go EV 8.5 pence kWh tariff, we easily add a Fogstar 30kWh battery, however we are 70 years old and will fit a new Worcester Bosch Combi boiler in the next 2 years.

 

[GUMPY]

We would happily change to a heat pump, if was a like for like, however even though our bungalow was a new build in 2017, the heating system uses 10mm push fit microbore. We have 4.4 kWh solar panels a 5.8 kWh battery and on Octopus Go EV 8.5 pence kWh tariff, we easily add a Fogstar 30kWh battery, however we are 70 years old and will fit a new Worcester Bosch Combi boiler in the next 2 years.

At least my microbore is copper soldered😉
I assume that as the battery is 5.8kWh it's a SolaX system you have, is it really easy to add a Fogstar as the battery voltages are very different. My 3 battery SolaX is 350V a single one is 117V how does this fit with Fogstar?

As you may recall I have just had fitted a new boiler with weather comp, hence my playing with the way it works. One thing I will say for those with combi gas boilers is turn the flow temperature down. Yes the rads don't feel as hot but they do heat the room and the boiler runs more efficiently and at lower power, thus using less gas.

 

[otherclive]

At least my microbore is copper soldered😉
I assume that as the battery is 5.8kWh it's a SolaX system you have, is it really easy to add a Fogstar as the battery voltages are very different. My 3 battery SolaX is 350V a single one is 117V how does this fit with Fogstar?

As you may recall I have just had fitted a new boiler with weather comp, hence my playing with the way it works. One thing I will say for those with combi gas boilers is turn the flow temperature down. Yes the rads don't feel as hot but they do heat the room and the boiler runs more efficiently and at lower power, thus using less gas.

Already do turn down boiler temperature once house is up to temperature, but only when there’s an external difference such as cold weather. At present it’s running very efficiently as it hasn’t even come on today apart from a quick boost to heat water for showers.

 

[Dustydog]

I'm sorry Dusty but you have succumbed to the misunderstanding which has arisen around heat pumps. The type and construction of a building does not reduce the efficiency of a heat pump, in exactly the same way they would not affect the efficiency of a gas boiler or electric radiator. They type of building affects how well any heat put into the building is retained and how effective that heat is, but it does not affect the the efficiency of the appliance itself.

Steady on Prof , I didn’t say that.

AHPs are a valid efficient heating system .. yes I said that.

but only when applied to a specific construction of building. Again yes but nowhere did I say “reduce the efficiency of a heat pump”.

Even with your tender years You know full well most on here know the building itself plays a big part no matter how efficient the AHP may be.
Please let’s not spoil the Season getting into semantics and pedantics 🤪

 

[ProfJohnL]

I think you are consistently reading HP as just the equipment itself. As myself, Dusty, JTQ, Gumpy, JC and others have indicated it’s the total system installation, which includes the house, that should determine the viability and efficiency of a heat pump installation. I think by now everyone is well aware that as a single piece of equipment a heat pump is more efficient than a gas boiler, your shed analogy explained that. But I venture to suggest that few if any existing houses built before 2000 could just swop a boiler for heat pump without substantial expense and disruption. If they did so, there’s a significant risk that the HP system would fail to meet expectations.

This is exactly why I am pointing out the difference between "efficiency" and "effectiveness" which are so often misused and consequently add to the general confusion, and the perception that "heat pumps" are believed to be only "efficient" when a building has been designed with one in mind thus implying unless the building has been designed with a heat pump in mind using a heat pump as such is inefficient, but how efficient a heat pump is not affected by the type of building!

There can be a cost impact of changing to a heat pump from other types of heating systems, and that depends on what type of system is already installed, if you were installing a whole building heating system from scratch the cost of a wet heat pump solution would would be similar to a fresh install of a gas system, and that would also apply if changing from electric storage heaters, toa wet system.

The issue is that whilst gas heating and heat pump heating looks similar, it is sufficiently different to make changing from gas to heat pump needing extensive changes to maximise effectiveness.

And there may well be some cases where for some practical reason the unique needs of a heat pump installation cannot be met, but the same can be said of any system, it's not unique to heat pumps.

But in general if you have a gas boiler the system and it can be replaced with a heat pump, the cost of replacement is what is causing legitimate concern. But that does not mean the heat pump would be inefficient.

 

[ProfJohnL]

I think you are consistently reading HP as just the equipment itself. As myself, Dusty, JTQ, Gumpy, JC and others have indicated it’s the total system installation, which includes the house, that should determine the viability and efficiency of a heat pump installation. I think by now everyone is well aware that as a single piece of equipment a heat pump is more efficient than a gas boiler, your shed analogy explained that. But I venture to suggest that few if any existing houses built before 2000 could just swop a boiler for heat pump without substantial expense and disruption. If they did so, there’s a significant risk that the HP system would fail to meet expectations.

That is correct, and I do so because its important to differentiate between efficiency and effectiveness.

The problem is that in some well publicised cases a heat pump has been installed into a property, and it has not performed as well as the owner has wished, and the owner has condemned the "Heat Pump" as being inefficient. That becomes the headline, and is what much of the general public take in and interpret as some on here have done so that the principle of heat pumps is inefficient, and that is a major obstacle to getting the message about heat pumps correctly understood.

In some of the cases it's usually the specification of the heat pump and its associated equipment which has been incompetently selected or installed, or the user does not know how to use the equipment that#s actually the problem, yet its invariably the innocent heat pump that gets blamed. All these then unfavourably colour the general perception against heat pumps when the heat pump is not the actual issue.