Battery discharging to grid when plenty of solar

11 comments started 2023-04-15 last 2023-04-20
GivEnergy ProductsHybridBattery
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#1 ZmGahH6yQBe

I've noticed this happen twice now. The battery will charge to 100%, then it will discharge to the grid at around 600w until the battery hits 98%, then the battery won't charge any more and stay idle for the rest of the day until the solar drops off, it will then discharge to the house as expected. During this period of discharge I will be generating more solar than the house needs so most of it will be going to the grid. For instance, I will be generating 4kw of solar, house is using 1kw, 3kw or solar going to the grid, battery is at 100% and discharging to the grid at 600w.

I have a 5kw gen2 hybrid inverter paired with a 9.5kw battery and 4.8kw solar array. Settings have not been changed at all since installation a weeks ago, battery charge mode is set to dynamic.

Does anyone know what's going on here? On a sunny day I would expect the battery to charge to 100% and stay there until later in the day when the solar drops off.

#2 Maxwell

ZmGahH6yQBe Is this similar to your power graph ?

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#3 TX200

ZmGahH6yQBe is your inverter a Gen2 (generation 2)?

Think there is a known bug with the Gen2 inverters. They sometimes get stuck in idle and need a restart from the portal (my inverter page) to get them running again.

Also in the newer firmware, the battery has to drop to something like 95% before it starts charging again - I guess to stop it oscillating a lot. I think that was intended to apply to grid/timed charge, not solar. Might be fixed/improved in the future if I remember correctly.

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#4 Ubarrow

I've just had this "stuck in idle" bug. Does anyone know whether this is due to be solved in a future software update?

It's pretty annoying!

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#5 Odinias

I reported this but not heard anything back (surprised, surprise).

Same thing happens with my 9.5kWh battery and 3.6kW hybrid inverter (gen 2). Reaches 100% from solar charging and then it starts to export to the grid until it drops down to about 95%. Much like yours, during the export phase, it won't accept any charge from solar despite being really sunny. It only starts charging back up again once it drops to 95% and then it just repeats the whole process.

So until this big is fixed, I'm getting around it by dumping the energy from the battery into my car once it hits 100%. I let the battery drop to about 90% and then let it charge back up again with solar. The downside is that I have to keep an eye on it every few minutes.

Ideally I want the battery to retain the 100% SoC and hold it for the evening. I don't want it exporting to the grid.

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#6 ZmGahH6yQBe

Maxwell Yes, that's similar to my power graph. It's happened quite a bit now.

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#7 ZmGahH6yQBe

TX200 Also in the newer firmware, the battery has to drop to something like 95% before it starts charging again - I guess to stop it oscillating a lot. I think that was intended to apply to grid/timed charge, not solar. Might be fixed/improved in the future if I remember correctly.

It seams like 98% is the figure it drops to on my battery for some reason. Although if the battery is used it won't charge until it goes under 95% I think.

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#8 ZmGahH6yQBe

I've noticed something odd happening today that might be related to this same issue. Today here has been a blue sky day with the odd tiny fluffy white cloud so I would expect to be great for generation. This morning while the battery was charging we were generating 4kw at peak time. But once the battery was full the solar generation fell off a cliff (well below 1kw most of the time) even though it's bright sunshine, no cloud cover and should be peak generation time. If you look at my graph you can see the generation drop off at the same time the battery is full and never recovers.

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#9 TX200

ZmGahH6yQBe how much are you allowed to export (what did it say on your DNO notice)?

Ask your installer or GivEnergy web chat/email support to check what it is actually set to.

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#10 ZmGahH6yQBe

We haven't had our DNO through yet as we were only installed a couple of weeks ago. Although we have exported over 8kw on a previous day and today it's only showing as having exported 2.5kw.

Also, earlier on the house was using 1kw, we were generating 0.5kw of solar and importing 0.5kw from the grid even though the battery was at 98%. It should have been using the battery if we were in fact only generating 0.5kw of solar.

Very odd

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#11 ZmGahH6yQBe

OK, so I just got an email back from GE regarding the battery discharging when at 100% and the solar drop off when the battery is at 100% and they replied with:

Both of these are known issues in the firmware - fixed in the upcoming beta release. We are in final test stages before launch.