Hello!
I'll start.
Heated area 200m2 (2,153 sq ft)
KfW 55 standard
Mechanical ventilation with heat recovery
Current outdoor temperature 6°C (43°F)
Heating energy consumption including hot water 35 kWh
Electricity consumption 9 kWh
COP 3.88
I'll start.
Heated area 200m2 (2,153 sq ft)
KfW 55 standard
Mechanical ventilation with heat recovery
Current outdoor temperature 6°C (43°F)
Heating energy consumption including hot water 35 kWh
Electricity consumption 9 kWh
COP 3.88
lin0r87 schrieb:
Photovoltaic system 7.2 kWp oriented south
One meter (bidirectional meter)
The total electricity consumption including the heat pump for the year 2021 was 4,334 kWh.
Generation from the photovoltaic system was 5,686 kWh. I’m not sure where to check the self-consumption values. It’s an SMA inverter. Those are great numbers! Out of curiosity, how does the bidirectional meter work exactly and what does it display? Since our system is over 10 kW, we had to install a separate generation meter to measure the production precisely. Is that the case with a bidirectional meter as well, or do the values mentioned above actually represent grid consumption (4,334 kWh) and feed-in (5,686 kWh)? If so, then the total consumption would be the grid consumption plus self-consumption (unknown amount).
D
Deliverer4 Jan 2022 11:18That’s correct. If there is no smart meter integrated into the system, you have to calculate self-consumption and add it to the amount drawn from the grid. However, most systems, especially those with storage and electric vehicle charge points (wallboxes), now include some type of smart meter.
Deliverer schrieb:
That’s true. If there is no smart meter in the system, you have to calculate the self-consumption and add it to the energy purchased. However, most systems—especially those with storage and a wall box—now include some type of smart meter. The value relevant for tax purposes is always generation minus feed-in, read from the calibrated meter of the grid operator (2.8.0).
D
Deliverer4 Jan 2022 13:21Sure. The smart meter should definitely follow the values from the inverters. In my case, it simply reads them (and adds them up).
That said, this is really an interesting point. Except for the feed-in meter, none of the meters are likely to be officially certified. So I can’t really provide 100% accurate data for tax purposes.
Most likely, for a household with a maximum of 30 kVA (beyond that, different metering rules apply, if I remember correctly), these are just minor details that nobody really cares about.
That said, this is really an interesting point. Except for the feed-in meter, none of the meters are likely to be officially certified. So I can’t really provide 100% accurate data for tax purposes.
Most likely, for a household with a maximum of 30 kVA (beyond that, different metering rules apply, if I remember correctly), these are just minor details that nobody really cares about.
Well, how is it even possible to verify this retrospectively, given the current level of digitalization in our administration and power grids ;-)
The readings already start to diverge. For example, with my Fronius inverter, I can also monitor self-consumption, and I record that as well, but the values always differ from the "official" measurement—sometimes more, sometimes less. A 5% difference is definitely possible.
In a normal household, though, this usually amounts to less than 10€ (about 11 USD) per year, so there’s no need to be more papal than the pope ;-)
The readings already start to diverge. For example, with my Fronius inverter, I can also monitor self-consumption, and I record that as well, but the values always differ from the "official" measurement—sometimes more, sometimes less. A 5% difference is definitely possible.
In a normal household, though, this usually amounts to less than 10€ (about 11 USD) per year, so there’s no need to be more papal than the pope ;-)
D
Deliverer4 Jan 2022 13:34guckuck2 schrieb:
but the values always differ from the "official" measurement. Where do you get values more official than from the WR?