Managing a timed boost charge on your Zappi during octopus go period

Hi I have been trying to tease out from various threads about how best to set my GivEnergy system (AC inverter) so that it doesn't discharge all its charge to my car if I set an overnight boost charge during the cheap Octopus Go period on my Zappi charger. A number of people have discussed elements of this but often it seemed before then got their EV or in the winter when they would be charging their GivEnergy system overnight anyway. Now that it is summer has anyone some straightforward instructions of what settings to use on the GivEnergy system so I don't wake up to a battery which has lost most of its charge overnight when I have been charging my car?

I'm still struggling with this too, but the only way that I can see it working is by setting a timed charge for your battery at the same time as your car. You can play with the %SOC of the home battery based on the season, i.e. in summer you can set is to something low (30-50%) and in winter fully charge the home battery ready for the next day.

timed charge to a SOC during cheap rate works, can also set the discharge rate to 0 or a low rate during the time the EV is charged to ensure its 0 or small amount discharged from the battery.

Timed charge to x %. Once the battery reaches it, it wont discharge to Zappi. If it is already higher, it will discharge down to your set %. So swings and roundabouts how you set it.

Would be good if we could schedule a discharge % limit in the GE App.

You could in HA using some code. As you can se the discharge slider from there, you would just need a control to activate the change, such as timer

Glengirlie what settings to use on the GivEnergy system

We've had our Givenergy inverter in ECO mode (Mode 1) since installation in January. The Zappi is set to ECO+ with 100% MGL (you need another CT from the Zappi on the grid connection to sense the grid charge/discharge), a time delay of (I think) 30 seconds at a minimum export of 200W. This hands over control of the EV charging to the Zappi. It won't charge the car unless the system is exporting more than 200W for at least 30 seconds (rules out the kettle switching off) and the MGL means that it won't actually divert export to Zappi until export exceeds 1.4kWh (the minimum the Zappi charges at). The Zappi takes all surplus output from PV up to the maximum of 7.2kW and varies this output to EV as the PV surplus varies.

Using these settings, the house battery doesn't discharge to EV but the PV gets diverted once it exceeds battery + house demand. If you are expecting a long sunny day, you can maximise your EV charging by reducing your house battery charging to say 1100-1500W, as long as you're confident that the battery will achieve your desired level before the end of PV production.

A downside is the extra CT required for the Zappi (if only I'd known at installation). One thing to watch is that if you power-cycle the Zappi or have to do a reset, it defaults to ECO mode which will discharge the house battery.

Tim Hi Tim, yes I have figured out the day time strategy with the Zappi - although I had not thought of reducing the house battery charging to 1500w - is that in the Charge Power setting on the app? Sounds like a good idea. I had been changing the Zappi to 'avoid charge' on the actual unit (we have the extra CT clamp so the battery shows as an icon on the myEnergi app). and possibly changing the Zappi to Eco rather than Eco+(I can't remember). But the idea of reducing the battery charging level seems simpler. We have a 13kw GivEnergy system with AC inverter and if it is a reasonable bright day then we probably only use about 30% of its charge between late afternoon and the following morning - so even if if we didn't charge it to full it would still probably be enough.
What I am trying to do is avoid draining the GivEnergy battery during the Octopus go period if I set my Zappi on a Scheduled boost between 0.30am and 4.30am. I have seen the suggestion that you could set your EV to charge for the first three hours (when if would take 3kw per hour from the house battery and the remaining 4kw per hour from the grid) then follow that up with an hour's charge of the house battery off the remaining Go period. This looks easy to achieve. Have you figured out any other way to stop losing all your house battery charge into the car? I have only charged our EV twice on boost since we got the house battery and both times it sooked most of my solar electrons out of the house battery - even if I had it set to 'avoid drain' on the battery.

Glengirlie I think the secret to avoiding off-peak house battery discharge while EV charging, is to set the house battery to also charge during the same time window. If you don't want it to actually charge (just hold the battery at a level and not discharge it to Zappi), then set the Timed charge % to whatever you need to tide you over to the start of PV generation. Whatever the SoC at the start of the off-peak window, the timed charge mode will either charge or discharge the battery to reach your set value and hold it there until the end of your timed charge window (which should coincide with the EV timed charge window).

Say you had 80% in by the off-peak window start and you only need 30% for morning routines. The house battery would discharge to 30% (to the car) and hold there until the end of the window. If you had 50% at the start of the window and wanted 70% for the following day, it would charge up from 50% to 70% at the same time as the EV is charging, and then hold there until the end of the window.

Glengirlie Charge Power setting on the app

TBH I only use the app to see what's happening at the moment. I only ever use the web portal to change settings. The settings are in Settings - Battery Options. I've found that if you're not in need of charging the EV, just wanting to divert surplus when it's available, then ECO+ with the other bits just works. If I do need to charge, I just put it into Boost or ECO, depending on how quickly it needs a charge and how much house battery we are willing to give up. We have a 12kWp system with two HY5 each with its own battery and most days when the sun is out, we can get the EV topped up although we have struggled the last few days.

Note for @Tim .

One thing to watch is that if you power-cycle the Zappi or have to do a reset, it defaults to ECO mode which will discharge the house battery.

The Zappi has a setting for what mode you want it to default to after a power cycle or reset. So you are not stuck with ECO mode. Mine is set to default to ECO+.

Simon_C The Zappi has a setting for what mode you want it to default to after a power cycle or reset

IS that in the app or at the device itself? I didn't notice it wherever it is but it wold be god to default it to ECO+ since I'd rather it didn't charge than charged from grid. Cheers 😀

Tim , it is on the Zappi display itself.

https://myenergi.info/viewtopic.php?p=51856#p51856

Hi all. Exactly the post I was looking for but I'm having a different issue - even when I think I'm setting my battery to charge during the off peak window, it still discharges.

Is anyone able to share a screen shot of how they having the battery setting so I can see what I'm doing wrong please?

Thanks. Liam

Lmcde3 what percentage are you trying to charge the GE battery to?

If the percentage is say 40% and you've got 70% in it at the start of the timed charge it'll use the battery rather than the grid till it gets to 40% then hover at that point till the end of the charge window.

I've got it set 100 AC Charge Limit enabled and the limit is set to 100%

I also have dynamic enabled.

Looking at the options...maybe I also need to enable AC charge...I'm using my phone so I didn't see the whole label. My fault.

So to make this work I would have
Eco enabled
AC limit enabled
AC charge enabled
With the time settings 12:30-04:30

Thanks for the advice.

Just collected my VW ID3 yesterday. I have the AC3 inverter and a Zappi v2. My settings are

GivEnergy inverter card
Settings
Eco enabled
Timed charge enabled (times set for my octopus go period)
Battery percentage set to the minimum I want to reserve for my house. Currently 30% so the extra can be dumped into the car. In the winter I will just move the slider up to 100%

Zappi settings
Set the zapi to eco+ mode 100% green
Sceduled timed charge to my Octopus go period
SOC limit set in the car to 80% (not all ev's can limit that)
Supply Grid Battery - Avoid both
Charge settings ECO+ settings - charge delayed 30 seconds

The car did have an issue with repeated stop starts on eco+ and I had to remove and reseat the charge cable later in the day but my scheduled charge worked fine! Pulled 3kw from the battery and 4.2kw from the grid until the car charged up to 80%.

The VW ID3 has known issues with the repeated start/stop of solar charging, documented by MyEnergi when using the Zappi.
I think some have found the v2.4 of the car firmware has improved matters.

Simon_C I forgot to mention my car came with the 3.0 software. I saw the 3.0 software worked better, maybe it does. But my 1 solar charge had the issue reported on older software. I may try upping the charge delay to 1 minute, or set an export margin of 400w or something.

With our eGolf, I leave the Zappi in ECO mode rather than ECO+ on a sunny day with clouds. I don’t mind the GivEnergy battery helping with the dips in generation. This way it avoids the charged delayed error and stops all the ramping up and down that imports from the grid when ECO+ starts charging the car.

In regards to the original post, if I set the Zappi to charge during GO this time of year, I pause the house battery from the app and resume when its done. Our GO hours finish at midnight so I’m able to do this. Prior to this I’d set the house battery to charge during GO hours if I know the car will be charging.

Hope this helps

Strange - I've got an ID.3 - software 2.3. No problems charging from solar. Same for the van - Maxus e-Deliver 3. I think Givenergy have changed things - I used to set a battery discharge time to avoid the Go Further period.