Export stopping early

Dai

When you have a chance can you looking at why my export is finishing nearly 20minutes before the end of the schedule window & the battery actual is well above the minimum set in the schedule.

I think it’s an issue of the import and export maximum throughput setting being now 20%+ different on the latest firmware from GivEnergy meaning max import rate is 2.4 and max output rate is now nearly 2.9. If you are doing calculations to set the close of the export window then these import vs export differences are having an effect on the algorithm.

User ref outstanding-equal

admin

Dai Yeah we have your max charge/discharge set as 2600, as that is the inverter max.

Are you sure the discharge is 2.9 kW rate DC->AC? How does that work with the inverter rate being 2.6kW max throughput?

Dai

admin the inverter has a max throughput of 3.6, in the advanced setting I have it set at 3.5.

The battery max throughput is different. It is quoted as max 2.5, but until the recent updates from Paul L at GivEnergy it always peaked at 2.42 in both directions which is why it is set at 2.4 in your advanced settings. Now the max is different for import vs export. This is a stated improvement from GivEnergy in this release for us on gen1 hybrids as well as faster response time on gen1 hybrid model produced after a certain date, in my case it can be nearly 2.9 now for export, subject to temperature.

The actual on the GivEnergy app for export is then confirmed by the figures from the octopus mini as well (see screenshots).

But this may only be a possible reason for my exports finishing early than expected. I have exports set through to 19.00. Without hitting the minimum soc remaining, the export is not utilising the full flux window for export and then possibly (if not enough solar) leaving me, without eco reset (which still occurs at 19:00), importing at the high flux price. When you are setting the discharge your setting you are sending through do not set the window stop to 19:00 as per the settings of my schedule on wonderwatt. Yesterday you sent the stop for 18:44.

(At the moment I have now disabled my schedule on WW, so as to hold any logs that may be required).

admin

Dai Without hitting the minimum soc remaining, the export is not utilising the full flux window for export and then possibly (if not enough solar) leaving me, without eco reset (which still occurs at 19:00), importing at the high flux price.

No, eco reset is also linked to the adjusted time. Yesterday we sent the eco reset through for you at 18:40, as you can see from our logs.

Your Giv logs should show the same.

As for the discharge rate, we have introduced a flag at the bottom of the export schedules for Giv inverters.

When we read this out for you it is set to 2600 and that's what we use. You could try to disable this, which should use your 2.4 value that you have specified.

Dai

admin but you also set eco at 19:00

But still not sure why you are disabling at 18:41 rather than user set 19:00 when you are nowhere near the SoC minimum as set in the schedule. in my case the minimum set on the schedule was 25% but at 18:41 there was still 50% Soc so it could have continued to the point when you did actual sent a 2nd “reset eco” at 19:00.

I’ve disable the flag you advise and will see what happens.

admin

but you also set eco at 19:00

Yes. But that's not really an issue. Main point was that eco gets reset and you're not drawing from the grid at peak flux time.

But still not sure why you are disabling at 18:41 rather than user set 19:00 when you are nowhere near the SoC minimum as set in the schedule.

It's down to the calculation, yeah, we don't recheck. We will look at recalculating at that point and keep the export running.

Dai

admin The thing is when consider stuff going forward is that now don't really on the Givenergy battery import and export rate to be the same from what I see from the software that Paul L is loading to us on the beta programme and existing documented capabilities are being improved (beyond the levels stated on the spec sheets) with their firmware releases 😉

Ifgow

Dai yes, I have suggested being able to set different rates for charge and discharge to allow finer tuning of protocols.

Regards,

Iain

Dai

Ifgow I think I jumped in to 2nd your request at the time. Thing is with the setting of the flag on the schedule as directed by WW, it still adjusted the schedule to stop earlier than I requested. Having different charge rates enterable would allow further customisation because every instance is different even if they are the same spec hardware.

Ifgow

Dai looking at mine, it’s almost as if it stops forced discharge early, then drifts down to the set % almost by the original set time.

Dai

@admin i have set the flag as requested to allow export at any maximum rate, but even then you are adjusting the stop time to a different end time that is set in the schedule. If you don’t know the max discharge rate, how can you then calculate your adjusted end time for each day ? I suspect you are still having to consider when to reset to Eco so you can send that at a time you think I could be close to my minimum SoC.

Ifgow

Dai I looked at a few discharge cycles and roughly worked out the % charge/discharge per minute at a given kW charge rate, then set the inverter and WW to the same charge rate. Sort of worked!