Average daily power usage increased by 2x since installing solar
Hi,

I have been scratching my head over this for days. Before installing my solar, over the past year, my average daily electricity usage had been on average 7kwh per day. I have looked at all the year-long bills and done the number crunching.

Since installing the solar, what FoxESS cloud data tells me is that on average, my daily consumption is around 17kwh per day. Some days go up to 25kwh.

NOTHING, literally NOTHING has changed in terms of appliances in the house, our usage pattern or anything.

The only thing that has changed in the solar and battery system that we have installed.

I know that the inverter + battery system would be drawing some parasitic charge, but it can't be up to 10kwh per day, More than my actual home usage.

This is mind-boggling. Has anyone else seen this issue?

My System:

Solar: 13.3kw
Inverter: FoxESS KH10 (KH series, 10 kW single-phase hybrid inverter)
Battery: Make/Model: FoxESS EQ4800-L9, Total capacity: 41.93 kWh
Re: Average daily power usage increased by 2x since installing solar
It's not normal, but can you post some images from the app to show the power flow (first screen in app), then click daily production and select the previous full day and screen shot that image as well - as much info as possible to help diagnose.

Irrespective of what the Fox app is saying, does your utility meter show that your daily grid consumption has increased ?
Re: Average daily power usage increased by 2x since installing solar
Here are some photos.
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Re: Average daily power usage increased by 2x since installing solar
For reference, this is my usage on March 26 before I installed solar. My average daily usage has been less than 8 kWh.
Screenshot 2026-05-10 at 6.32.19 pm.png
Re: Average daily power usage increased by 2x since installing solar
If you forget the magnitude of the load for the moment, the graphs appear to show the system running normally, obviously VPP controlled and looking like the battery is charging normally from PV and being used to export later in the evening.

You are exporting a lot of power to the grid and your import looks low.

So all of that said, there is nothing fundamentally wrong in the operation of the system, and power flow directions are correct - but the load consumption is high.

The graphs are showing high load consumption, typically low (average ~500 watts/h) until 2pm and then it goes high until about 10pm (average 1.5kw/h) with lots of peaks to 3 or 4 kwh.

Is there anything in the house that could be taking such large amounts of power, water heaters / AC etc..

It is possible that the CT clamp is not correct i.e. the CT clamp is the wrong ratio (it should say 100A/33.3mA on it) - or if a meter has been used the ratio has been set incorrectly (possibly it is clamped to the wrong cable or being influenced by another magnetic device in close proximity).

If you have ruled out any possibility of using that much load, I would suggest getting your installer back to check the metering configuration.
Re: Average daily power usage increased by 2x since installing solar
Just whilst i’m thinking about it, I wanted to check that your solar panels are connected to the KH inverter and you don’t have any other external PV generation ?
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