Minor discharges to grid

I’ve now had my system installed since September and I’m pretty happy with it. I’ve noted however that when Solar is producing sufficient to run the house, and a small amount of grid export, the batteries )which aren’t required to be discharging to the house are sending small amounts (5-35W) to the grid, pretty much consistently. Nothing shows on the grid CT of my myenergi app (maybe too small).

It’s not a constant back/forth like it’s balancing, but it’s small enough I’m wondering is it simply system noise?

Smk82 I think the small amount of excess export is by design to reduce any grid usage to zero,
It is better to waste a bit of generation than cost money by importing.
You will notice once generation stops it flips the other way, import a small amount than throw stored energy away to the grid.

Smk82 there will be some small import/export while the invert ramps up/down to meet demand. It can take the inverter up to 30 seconds to react.

If you're looking at the portal as well these are only snapshots in time every 5 minutes so won't be fully accurate.

Oh I’m aware of this. The solar is covering house load completely. Just apparently the battery is discharging minor amounts to the grid (when there hasn’t been a load in the previously 30mins or so to ramp up/down, and so normally account for such observations…

athresuk yeah, but shouldn’t the batteries charge if there is excess rather than sending to the grid?

Smk82 Depends on how much excess there is, can you post up a plot of your issue (and detail the HW you have), this will help identify if this is normal behavior or something else.

As said by Cdent above, the portal only gives a snapshot once every 5 minutes so can be misleading at times, I use a separate CT clamp monitor (IotaWatt) for system analysis with problems as it has a much faster sample rate (700 samples/sec)

'I have my system set to discharge at 2 periods, set for when my heat pump is used. I have the battery set to discharge at 1060kWh to increase the period the battery discharges. I have noticed 2 things: the battery discharges to the grid outside my set times and although I have disabled Eco and Timed Export the system enables these again. I have spoken to support and received the following reply:

I believe the reason that your battery is discharging outside of the set times is because of the logic within the backend of the systems is broken in regards to the timed discharge register this means that unfortunately the feature is not working as expected.'
This will be fixed within the future updates to the app/portal.

For now I would recommend using eco mode instead of timed discharge.'

Still not sure why the Eco enables without me changing the settings (I know this is default position) but unless the inverter is restarted it should not change.

I have just had batteries installed to make use of my EV tariff, no PV panels. I also see an indicated export to the grid of up a few 10s of watts. I do not have any agreement to export to the grid, I'm puzzled rather than worried, but would like to understand why it is happening.

athresuk
Twin 8.2 batteries/3.0AC inv

Not quite sure how to upload an image here…