The generation of both my SMA inverters is uploaded to PVoutput using SBFspot, each with its own child system witch is aggregated in the parent.
The export and import of my Dutch smart meter is also aggregated in the parent using the V2 (export) and V4 (import) power values and N=1.
I compared the numbers in PV output with the meter readings of my smart meter over a period of a week.
Based on my smart meter readings and the generation of my PV system (according to PV output) I calculated the consumption (consumption = generation + import - export).
According to PV output my consumption was 165,838kWh, but according to my calculation (based on the meter readings) the consumption is 139,461kWh. So that is a difference of 26,377kWh for a period of a week! (we use comma as decimal separator).
The upload to SBFspot is done with Openhab using a Rpi. The upload of the smart meter is also done by Openhab on another Rpi. Both uploads are not at the same moment, but within the same time frame of 5 min.
Aggregation mode of both child’s are set to “Solar” and of the parent to “All”.
Net calculations of the parent is set to “Enabled”
Net Method of the parent is set to “Average”.
Status interval of all the systems is set to 5 min.
Who has any idea what causes this difference?