ᐅ Gas with solar thermal? Or heat pump with photovoltaic? Advice needed
Created on: 5 Feb 2020 08:57
M
Micha8589
Good morning to the forum,
I have been researching heating options for quite some time and have gathered a few opinions, which have only made me more uncertain about my decision. That’s why I thought I’d ask the forum.
My family (2 adults, 1 child) is planning to build the following single-family house at the end of this year or beginning of next year:
Single-family home with pitched roof
Approximately 115 m² (1,237 sq ft)
Solid construction (calcium silicate brick ground and upper floors, brick-clad)
No KFW standard
Building location: southern Mecklenburg
Unfortunately, I can’t provide an energy performance certificate or heating load calculation yet, as the preliminary offer is still being prepared. I am also aware that a general statement can’t really be made since every house and heating behavior is individual.
The construction company advised us to install a modern hybrid heating system consisting of a gas condensing boiler and two solar thermal panels on the roof for domestic hot water, as the initial costs are relatively low (plus installation of the central gas connection), and this technology has proven reliable. The entire house is planned to have underfloor heating. According to the company, they have had very positive experiences with this and consider the technology future-proof. (There is also the idea of a fireplace in the living room.)
On the other hand, I think gas prices will not get any cheaper in the future, and the topic of CO₂ taxes (especially concerning the fireplace) worries me somewhat.
In theory, I would prefer to install a geothermal heat pump combined with a suitable photovoltaic system because this would make me independent of fossil fuels and allow me to heat “off-grid” to a certain extent, depending on efficiency. However, I am hesitant because of the very high initial costs and don’t really know how these compare to operational costs. I also can no longer realistically assess which technology offers the best cost-performance ratio (except for air-source heat pumps).
As you can see, I am completely undecided and hope to get some feedback and expertise from the forum.
Thanks in advance for your replies.
I have been researching heating options for quite some time and have gathered a few opinions, which have only made me more uncertain about my decision. That’s why I thought I’d ask the forum.
My family (2 adults, 1 child) is planning to build the following single-family house at the end of this year or beginning of next year:
Single-family home with pitched roof
Approximately 115 m² (1,237 sq ft)
Solid construction (calcium silicate brick ground and upper floors, brick-clad)
No KFW standard
Building location: southern Mecklenburg
Unfortunately, I can’t provide an energy performance certificate or heating load calculation yet, as the preliminary offer is still being prepared. I am also aware that a general statement can’t really be made since every house and heating behavior is individual.
The construction company advised us to install a modern hybrid heating system consisting of a gas condensing boiler and two solar thermal panels on the roof for domestic hot water, as the initial costs are relatively low (plus installation of the central gas connection), and this technology has proven reliable. The entire house is planned to have underfloor heating. According to the company, they have had very positive experiences with this and consider the technology future-proof. (There is also the idea of a fireplace in the living room.)
On the other hand, I think gas prices will not get any cheaper in the future, and the topic of CO₂ taxes (especially concerning the fireplace) worries me somewhat.
In theory, I would prefer to install a geothermal heat pump combined with a suitable photovoltaic system because this would make me independent of fossil fuels and allow me to heat “off-grid” to a certain extent, depending on efficiency. However, I am hesitant because of the very high initial costs and don’t really know how these compare to operational costs. I also can no longer realistically assess which technology offers the best cost-performance ratio (except for air-source heat pumps).
As you can see, I am completely undecided and hope to get some feedback and expertise from the forum.
Thanks in advance for your replies.
T
T_im_Norden7 Feb 2020 11:14Playfulness, at least for me, refers to attempts at optimization (see heat pumps in the red forum) and the analysis/visualization, for example with the Nibe Uplink.
This is something that would seem rather out of place with a gas boiler.
This is something that would seem rather out of place with a gas boiler.
T_im_Norden schrieb:
That is something that would be rather out of place on a gas boiler. That is a misconception. Even gas boilers can be optimized (in fact, they should be), and manufacturers are well aware of this. They have recognized market opportunities and offer tools accordingly.
However, it is easier to take this step with a gas heating system than with a heat pump, because the technology tolerates many user errors and a few degrees of temperature reserve here and there are not really noticeable.
Heat pumps are still an immature technology. Everyone in our building area is having problems with them. Additionally, there are issues with noise, high energy consumption, limited durability, and the need for a suitable installation location.
When in doubt, it’s better to choose gas!
When in doubt, it’s better to choose gas!
In our development area, all heat pump owners are satisfied; they operate without problems, and there are no complaints about energy consumption. Maybe you just have poor installers in your region. I wouldn’t generalize either way.
Well, it can support charging, but you won’t be able to cover a large share.
Basically, it doesn’t matter whether you choose gas or a heat pump; in a modern new build, neither option will break the bank in the long run. If you plan the underfloor heating so that the supply temperatures suitable for a heat pump can be achieved, you keep your options open for switching later.
One thing I learned during construction is that with three people, you get three opinions — all completely opposite — and all are experts. At your appointment, you will get his opinion.
Micha8589 schrieb:
As already mentioned, the combination of a heat pump and photovoltaic system is a significant factor for me, as it is a new technology that at least appears to be a future-proof and economical solution. Some might even argue: …then I can charge my electric car with the photovoltaic system… which, from my perspective, is nonsense because you would need a huge photovoltaic system in the low-sunlight northern Germany.
I have an appointment with the consumer advice center in two weeks, where I will discuss the topic with an independent engineer with a diploma. Let’s see what he says?! I will definitely report back!
Well, it can support charging, but you won’t be able to cover a large share.
Basically, it doesn’t matter whether you choose gas or a heat pump; in a modern new build, neither option will break the bank in the long run. If you plan the underfloor heating so that the supply temperatures suitable for a heat pump can be achieved, you keep your options open for switching later.
One thing I learned during construction is that with three people, you get three opinions — all completely opposite — and all are experts. At your appointment, you will get his opinion.
T
T_im_Norden8 Feb 2020 15:21One should also not forget that this is about relatively small differences in monthly costs.
Whether I pay 80 euros or only 60 euros usually does not correspond proportionally to the differing costs of construction.
Whether I pay 80 euros or only 60 euros usually does not correspond proportionally to the differing costs of construction.
20 per month = nearly €5000 over 20 years
Gas connection cost €2000 once
Fireplace cost €2500 once
Chimney sweep €100 per year = €2000 over 20 years.
Gas will inevitably become more expensive due to CO2 taxes.
With photovoltaic systems, I can install a battery storage later if electricity becomes too expensive. With gas, that's more difficult...
Batteries are getting cheaper all the time...
Gas connection cost €2000 once
Fireplace cost €2500 once
Chimney sweep €100 per year = €2000 over 20 years.
Gas will inevitably become more expensive due to CO2 taxes.
With photovoltaic systems, I can install a battery storage later if electricity becomes too expensive. With gas, that's more difficult...
Batteries are getting cheaper all the time...
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