á 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. Thatâs why I thought Iâd 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 canât 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 canât 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 COâ 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 âoff-gridâ to a certain extent, depending on efficiency. However, I am hesitant because of the very high initial costs and donât 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. Thatâs why I thought Iâd 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 canât 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 canât 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 COâ 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 âoff-gridâ to a certain extent, depending on efficiency. However, I am hesitant because of the very high initial costs and donât 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_im_Norden schrieb:
Disadvantages of heat pumps
The heating system and heat pump design must be done perfectly
Uncertainty in electricity price developments
Equipment costs
Installer needs to be very knowledgeable Sometimes it is made out as if installing a heat pump is rocket science. In reality, all parties just need to do their job properly and not guess or estimate roughly. Our general contractor installs heat pumps in 5-10% of about 400 houses per year. The planned indoor temperatures donât exactly match what we have, and with 23-24°C (73-75°F) in one-third of the house, itâs already not cold. Despite these less-than-perfect conditions, our heat pump achieves a seasonal performance factor (SPF) of over 4.
Zaba12 schrieb:
In our region of Middle Franconia, according to PVGIS, about 3% of the annual photovoltaic output is lost in January. This means you will hardly notice it regarding the heat pump, but that doesnât mean photovoltaic systems are a bad investment over 10-15 yearsâin fact, quite the opposite. However, one should forget the idea that the photovoltaic system noticeably supports the heat pump. st.From my own experience, I agree. Of the nearly 90 kWh (kiloWatt-hours) generated in January, we used 77% of that energy. Hot water accounts for nearly 30 kWh (kiloWatt-hours) per month. Heating uses 315 kWh (kiloWatt-hours). With a south and west roof combined system of 6.3 kWp (kiloWatt peak), itâs not a very large installation either.hegi___ schrieb:
I donât know your energy standard, but with a KfW55 plus photovoltaic system, you can easily manage with half that amount.Based on the Energy Saving Ordinance minimum standard. How much more have you spent on the air-to-water heat pump, rooftop photovoltaic system, and KfW55 compared to me? Our costs are 360 to 720 euros per year. Over 10 years, thatâs 3,600 euros; over 20 years, 7,200 euros...
T
T_im_Norden6 Feb 2020 11:44hegi___ schrieb:
Individual cases are always a bit tricky...
I don't know your energy standard, but with a KFW55 standard and photovoltaic system, you can easily manage with about half.
ares83 schrieb:
Still, our heat pump achieves a seasonal performance factor of over 4.What are your monthly costs with the heat pump?Similar topics