FoxESS Community - Owners & Installers Forum

Hello all,

like some others I am struggeling with the shown Data in FOX ESS 2.0 APP. The shown explanations in the forum make no sense for me.

Yesterday I had

4.1 kWh production
2.7 kWh self consumtion
1.4 kWh export to grid

consumption 5.3 kWh
bought from grid 5.2kWh
Self-sufficiency 0.1 kWh!!!!!!

Sorry this makes no sense to me. Can someone help? Second, why is something sold to grid when my battery was never over 30% load?

Thanks!

Your solar Production was 4.1 kWh (A)
You Exported 1.4 kWh (B)
So your Self-Consumption is (A-B) = 2.7 kWh (C)
Your Self-Consumption ration is (C / A) = 66%

Your consumption was 5.3 kWh (D)
You Purchased 5.2 kWh from grid (E)
Your Self-sufficiency is (D-E)=.1 kWh (F)
Your % self-sufficiency is the ration between (F / D) =2%

Your system efficiency (Input/Output) is:
Input = Production (A) + Purchase (E) i.e. 4.1 + 5.2 = 9.3kWh
Output = Export (B) + Consumption (D) i.e. 1.4 + 5.3 = 6.7kWh

Your system losses is the difference between Input and Output (2.6kWh ) which is 28.0% of the Input ~ 72.0% efficient.

Measured over a small period there will be differences in the amount of energy that went into and out of the  batteries 
i.e. if the battery SoC is different at the start and end of the period these figures will not be accurate which is why it is best to view over a full month to get a more precise reading.

There are losses at multiple stages i.e. in the MPPT's, the DC to AC conversion from solar/batteries to feed the house,
AC to DC to charge the batteries and in the chemical process of storing and recovering energy (Fox say approx 95% round trip efficiency) and of course in keeping your inverter and BMS running.

On why you are exporting you haven't provided enough information any number of things can make that happen such as your work mode settings, large peaks of solar larger than your battery charge capacity etc.. - but the more likely is the batteries are cold and the solar power at some points of the day was greater than the battery could charge at and so any spare will go to export.

Hello Dave,

thanks for you explanation. 72% EFFICIENCY sounds very bad. But I aggree, I will track some more time and come back if it is still that worse.
Regarding the Battery (10kwh), it is inside the house (basement) so always 16-20C°. Or do you mean with "cold" is when battery starts loading after standby in general? It was a cloudy day so this should not be an issue.

I'll still think the visualisation could be improved.

Yes agree 72% is low but over 1 day your results really won’t be accurate and with low generation and consumption your system losses appear larger - it is best to view these stats on a monthly basis. The winter months of December and January are always the worst because of the suns low elevation.

I meant cold as in less than 10C where the temperature has a large effect, but if they are between 16 & 20C temperature there would be an effect but much smaller - what type and how many batteries do you have? as the temp effects when charging tend to be magnified on smaller packs because of their lower voltage.

I have one EK11 Battery (10kWh) + H3 - 6 converter + 7,3 kWhp (splitted East - West to the sun)

New-USER wrote: Fri Jan 24, 2025 7:00 am I have one EK11 Battery (10kWh) + H3 - 6 converter + 7,3 kWhp (splitted East - West to the sun)

Ok thanks an EK11 battery at 16-20C shouldn't have any charging problems as they are high voltage.

As you are 3 phase (H3-6) you would generate as a balanced 2kW (max) across each of the 3 phases and so it is possible if you were generating 4.5kw solar, for you to be consuming 1.5kW on one phase whilst exporting on the other 2 - as you say best to keep an eye on it and if you are unhappy contact your installer for their advice.

I am getting similar odd numbers. I have also connected the FoxCloud to Home Assistant. In Home Assistant I have set up variables to calculate the daily load and grid consumption based on the current consumption values provided by FoxCloud. Whereas for the grid consumption the values calculated by Home Assistant are very close to the ones shown in the app, the load values calculated by Home Assistant are much higher and look more plausible to me. Why? The equation Daily Load = Daily PV production + Daily Grid Consumption works (currently I an not exporting anything and there is no power in the battery carried over from one day to another due to the low production). I have also noted down the values of the load counter installed in my fuse box and the daily values are also very close to the daily load values calculated by Home Assistant.

My setup: Inverter = H3-10.0-E and Battery = EK11

Can anybody confirm my experience?