ᐅ Photovoltaic System and Air-to-Water Heat Pump – Profitability for a Single-Family Home Built to KfW 55 Energy Efficiency Standard
Created on: 11 Jan 2022 23:19
M
Maxwell8
Hello,
we are building a fairly large KFW55EE house with external dimensions of approximately 10x14m (33x46 feet) and a roof pitch of 15° (roof surfaces facing north and south).
We have a lot of window area (100m2 (1,076 sq ft)) and expect an energy consumption of about 7-9k kWh per year due to the size.
Heating is provided by underfloor heating with the Tecalor THZ 504 air-to-water heat pump.
Feed-in tariffs are no longer significant, but the electricity price is currently 45 cents/kWh.
We would have to finance the photovoltaic system ourselves because there is no sufficient budget left.
> From a profitability perspective, does a photovoltaic system make sense in our situation?
> What size and costs should we expect?
> Should it be installed directly or should we first prepare with conduits?
> We also have an attached 6x6m (20x20 feet) flat-roof garage on the east side. Would adding photovoltaic panels there be beneficial?
I will, of course, speak with companies but would like to gather some opinions beforehand.
Thank you in advance. 🙂
we are building a fairly large KFW55EE house with external dimensions of approximately 10x14m (33x46 feet) and a roof pitch of 15° (roof surfaces facing north and south).
We have a lot of window area (100m2 (1,076 sq ft)) and expect an energy consumption of about 7-9k kWh per year due to the size.
Heating is provided by underfloor heating with the Tecalor THZ 504 air-to-water heat pump.
Feed-in tariffs are no longer significant, but the electricity price is currently 45 cents/kWh.
We would have to finance the photovoltaic system ourselves because there is no sufficient budget left.
> From a profitability perspective, does a photovoltaic system make sense in our situation?
> What size and costs should we expect?
> Should it be installed directly or should we first prepare with conduits?
> We also have an attached 6x6m (20x20 feet) flat-roof garage on the east side. Would adding photovoltaic panels there be beneficial?
I will, of course, speak with companies but would like to gather some opinions beforehand.
Thank you in advance. 🙂
R
RotorMotor24 Jan 2022 09:53Basically, Hangman’s statement about the qP matches mine.
I estimated 2, Hangman 1.6. On the internet, you often find 2.7 for electricity.
That neatly adds up to 3500 kWh. ;-)
I estimated 2, Hangman 1.6. On the internet, you often find 2.7 for electricity.
That neatly adds up to 3500 kWh. ;-)
The 2.6 value was used until 2019/20... then the heat pump factor was changed to 1.6 to promote them more (that’s what I meant by politically motivated). I don’t know if there have been any further changes since then (but I don’t think so). However, it doesn’t really matter, since in @Maxwell8’s calculations, the final energy demand should be explicitly indicated (regardless of the factor used).
Thank you, I had also read about the factor of 1.8. The question remains whether to use net floor area or living area.
If you visit the official website of the heat pump manufacturer, select my air-to-water heat pump, and enter all the information (living area, KFW standard, usage behavior, postal code, etc.), I get the following results:
Total heating demand including domestic hot water: 10,592 kWh/year.
This corresponds to a total electricity demand of 3,130 kWh/year (space heating, hot water, ventilation).
I will probably just calculate with 4,500 kWh, so I’m somewhere between the two calculations.
If you visit the official website of the heat pump manufacturer, select my air-to-water heat pump, and enter all the information (living area, KFW standard, usage behavior, postal code, etc.), I get the following results:
Total heating demand including domestic hot water: 10,592 kWh/year.
This corresponds to a total electricity demand of 3,130 kWh/year (space heating, hot water, ventilation).
I will probably just calculate with 4,500 kWh, so I’m somewhere between the two calculations.
D
Deliverer26 Jan 2022 08:21If it's more than 3000, something is wrong. For me, 5000 is enough for 260 sqm (2800 sq ft) of an uninsulated older building, NAT -10°C (14°F) and 22°C (72°F) indoor temperature.
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Benutzer20023 Feb 2022 18:38Mahri23 schrieb:
A new house with the right photovoltaic system is really enjoyable.I can only agree – and that in winter. It gets even better on the weekend:Similar topics