What is getting exported to the grid is incorrect in the Dashboard which gives false stats.

[Stephen2615]

Seasons Greetings,

I know that I have raised this before but never properly followed through. I have two inverters (5.9 and 3.5 kW each of them is single phase) and combined, they routinely create just above 8 kW in the middle of a sunny day. I have three phase power (because of my AirCon) as well a Powerwall II. That 8 kW (as an example) is known to the Powerwall and presents it perfectly.

The Dashboard seems to get confused with the amount of load the house has as it doesn't seem to know that "something" is exporting more than 5 kW. Perhaps that is the smart meter.

My energy provider offers five minute readings and I picked a good day where I exported above 5 kW at any moment in time.

This graph shows the kW exported to the grid.. The time is one hour out due to the provider not updating for daylight savings.

The Powerwall Dashboard almost never shows more than about 4.5 kW to the grid.

The To Grid number is wrong as that day I exported nearly 41 kWh to the grid (energy provider data). This means the Load/Home reading is also incorrect as there is no way my house uses 35.9 kWh and my records suggest only 10.53 kW was used by the house before any grid was used (total home usage would be 15.3 kWh). The Dashboard got the power from the grid almost right which is probably making up for the provider not changing to day light savings.

I suggest that the home/load adds the excess power above 5 kW that goes to the grid to it's total which is not the real home/load.

This isn't a real problem but I thought I would raise it as I am sure other people have something similar with multiple inverters.

I think your work is awesome and it probably is perfect with a simpler solution. FWIW, the Home Assistant integration also gets it wrong.

Thanks for reading this.

Stephen

[jasonacox]

Hi Stephen, thanks for sending this! I appreciate the kind words as well about the project. And yes, I confess, it is 100% designed for simple installations. But that doesn't mean it can't be customized.

The kW data it plots over time is coming directly from the Powerwall meters aggregate API (http://pypowerwall:8675/api/meters/aggregates) so somehow the Powerwall thinks that is the export value. For you installation it sounds like that isn't the full total. If I were you, I would ask to get the full design details and start figuring out how the data should be added up to get to the correct values. I would then update telegraf to sum those up before storing them in Influxdb.

If you do figure it out, please let us know! As you say, I'm sure others have the same or similar setup.