question

Hi @Cadoxa,

If you are planning to load the ESS assistant there is a nifty feature to limit the maximum discharge from your battery during the night.

It is called "limit inverter power".

Typically this value is set to the house's normal night time consumption (500W-1000W, for lights and fridges etc.), which allows for the battery to be drained slowly while mixing the battery power with energy from the grid.

Below is an example of such a setup. (Inverter limit is set to 1000W)

If you setup this feature and the i3 needs charging it will take a maximum of 1000W to charge the i3 and to provide power to your house. Unfortunately, it does not discriminate between house consumption and charging the battery of the i3, but at least your battery won't be drained in 2 hours.

Not sure if this is your concern.

Best Regards

Hi Riaan, not exactly, but nice workaround though :)

Thankx !!

Hi @Cadoxa

I'm looking at a similar setup, how to intelligently charge an EV using solar panels.

I'd suggest looking at an EV charger that is optimised for solar power. I'm looking into the Mienergy Zappi for example, which uses a CT sensor on the grid connection to sense when excess solar is being exported and will try to charge the EV to use up any excess and prevent any import from the grid.

During the night however you have the same problem as me where the ESS system will try to charge the EV from battery power, which is somewhat inefficient.

I think you can use the limit inverter power feature above along with the timed charging available on most EVs. If you set the limit to something below 1.4kW between the hours of say 1-4am and set the EV to charge during this time, it will use the minimum amount of battery power to charge the EV (1.4kW is the minimum rate at which most EVs can charge)

Hello to all BMW i3 and of course to all other EV owners.

I had the problem in a little bit other way round. I can switch my wallbox to a PV- energy mode only. This means it charges the BMW i3 exclusively with energy with comes from the AC-wired PV. It does it like the Victron ESS. It get information from an additional energy meter how much PV energy will be send back to grid and controls corresponding the EV charge current of the wallbox so grid meter is 0. But since Victron ESS installed, the Multiplus collects all PV energy first and charges the ESS batterie and there is no energy left for my BMW i3 ;-(

I will go to solve this problem with the auxiliary input No. 1 and the assistant "charge current control"

My wallbox is controlled thru a Siemens Logo! and I can easily close a additional potential free contact with is connected to the Multiplus auxiliary input. In this moment this idea isn't already realized and tested. But I am quite sure this will work. I just discovered this challenge, when doing the first Solar based charge of the i3.

Back to the problem of @Cadoxa loading BMW i3 exclusively with energy from the grid, I wasn't aware of this problem. But it will hurt me in winter, too. My idea how it can be solved is in case there is similar to the assistant "charge current control" an assistant like "discharge current control" it should be simply by closing the 2nd auxiliary input during charging an EV-car that only grid energy is used to charge and to prevent of using energy from the ESS batteries. I looked through the list of assistants but I couldn't find an assistant "discharge current control" - Perhaps such an asssistant can be usefull for many other ideas in this direction, too and Victron will help and do such an assistant. [moderator edit: please stop @mentioning mods]

please have a look to this idea. Or there might be already an assistant available which can be used for this and I didn't found.

Looking forward what community thinks.

DayAndNight

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Came across this tread as i'm looking to start my EV journey and don't want to discharge all my stored energy into my car. Also looking at a Zappi. I'm thinking the best way to stop it using the battery at night is to scheduled charge. setting it low would stop any charge coming out of the ESS battery.