FoxESS Community - Owners & Installers Forum

Hi all,
I had my Fox ESS battery installed by Octopus Energy just over 3 weeks ago and the battery has been working quite happily in self usage mode. (I am in Cambridge, UK - not sure where this forum is based)
When checking the status of the battery at lunchtime today it had charged from around 8.30am right upto 100% full. The battery has now sat at 100% SOC all day rather than providing power to my home. This is the first time it has done this in 3 weeks and has cost me around £14!
The only thing that changed last night was I plugged my EV in for the first time and charged from 11.30pm to 05.30am.

I have now set up a schedule for the battery to charge from grid overnight from 11.30pm to 05.30am as I am on Octopus Intelligent go tariff.

When I am working from home alone can I set the battery to export to the grid for the 15p export rate?

When I spoke to Fox service via Whatsapp they said that the battery is working normally and the reason it fully charged is because of the solar PV. BUT I only have a 2.7kW system and the rest of the charge came from the grid on an expensive tariff.

Could someone please help me as I want to make sure my battery system is set up properly for my home?

Thanks

nigeldent07 wrote: ↑Mon Mar 02, 2026 4:25 pm This is the first time it has done this in 3 weeks and has cost me around £14!
The only thing that changed last night was I plugged my EV in for the first time and charged from 11.30pm to 05.30am.

I have now set up a schedule for the battery to charge from grid overnight from 11.30pm to 05.30am as I am on Octopus Intelligent go tariff.

That £14 at the peak rate (est 32p) would be almost 44kWh of power from the grid on peak pricing.

I assume you might be new to IOG, if yes, you need to wait 1-2 days for Octopus to recalculate and the £14 will drop down drastically. It does this all the time, so you will learn to ignore it, and check later or your bills.

If you look at this first picture, you will see Sunday used less power than Monday If you now look at the estimate costs, Sunday looks much higher. If I wait for Tuesday or Wednesday, this will recalculate and Sunday cost will drop.