ᐅ Determine the electricity consumption of the air-to-water heat pump as a proportion of the total power consumption.

Created on: 2 Jan 2022 13:38
T
Tx-25
Hello, in 2020, we consumed about 6,800 kWh of electricity. Of this, 1,750 kWh was self-consumption from our photovoltaic system. This means our electricity purchase from the grid was 4,062 kWh. Since we have an air-to-water heat pump, the heating also runs on electricity.

How can I now separate the electricity consumption of the air-to-water heat pump from the overall costs?

We have a meter on the electrical distribution board showing 1,294.59 kWh. Additionally, there are two heat meters installed (12,082 and 2,477 MWh).
T
Tx-25
3 Jan 2022 18:52
Here are the promised pictures.

The heat meter showing a reading of about 2,400 is disconnected from the pipe leading to the hot water storage tank.

White electrical distribution box with digital Finder meter on the right and SMA Energy Meter below.


White ZENNER zelsius measuring device with display, pipes and valve visible on the left.


Digital Zenner electricity meter with display showing 12,168 kWh.


Insulated heating pipe with valve, copper pipes and boiler in the background.
J
Joedreck
4 Jan 2022 06:33
driver55 schrieb:

And with 1000 kWh less “total consumption,” that makes…

The calculation really doesn’t add up.

That remains his secret. Yesterday, assuming 3800 kWh instead of the current 2800 kWh for heating, the annual performance factor was about 2; now it’s supposed to be around 5. 🙄

Now, now, everyone can make a mistake sometimes.
In the second calculation, I divided the delivered heat output by the (presumably) supplied heat input.
Thanks for pointing that out so kindly.
D
driver55
4 Jan 2022 08:37
Tx-25 schrieb:

Here are the promised pictures.

The heat meter showing about 2,400 is disconnected on the pipe leading to the water storage tank.

Ok, so it really is the suspected MWh. 😀
I hope you’re diligently filling out the Excel spreadsheet so that the daily difference will eventually allow you to correctly assign the readings.
(All electricity meters, heat meters, and the values the heat pump itself records daily).
D
driver55
4 Jan 2022 09:11
Tx-25 schrieb:

Of this, 1.750 kW is the self-consumption from our photovoltaic system.
Where do you read that? Are there additional meters besides the main electricity meter?
Tx-25 schrieb:

Heat meters installed. (12.082 and 2.477 MWh).
Please note! 12.082 and 2.477 MWh!
T
Tx-25
4 Jan 2022 16:29
driver55 schrieb:

Where do you read that from? Are there additional meters besides the main electricity meter?


Note! 12,082 and 2,477 MWh!

I get the data from the photovoltaic system’s app. I assume the device from SMA inside the distribution board is providing the data. The data there always matches the electricity consumption and so on.
D
driver55
4 Jan 2022 17:43
Tx-25 schrieb:

I get the data from the app of the photovoltaic system

And the meter on the power rail?
I thought that was the yield from the roof?
Please show the table at the end of the month then…