Venus OS3.10: New ESS "Self consumption from battery" setting

Latest Release Candidate v3.25… this is now really cool!


Again, you are most welcome. And shout-out also to @warwickchapman for putting some drive behind it. As I always say, these things get done faster if it goes through the right channels, from the installers/resellers/sales people :slight_smile:

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That is a very nice feature indeed!

I think I know what this does, but I couldn’t really be definitive from the write-up.
Can someone lay it out for me in practical terms?


The changes are still in Dev but are outlined here:

Yes, like I said I read that.
Are we talking about “AC2 out” tripping at a pre-determined SOC whilst the grid is still present?
Or, are we talking about not assisting loads upstream of the inverter, but downstream of the meter?
Whatever way, does it pre-suppose a certain way of segregating essential and non-essential loads?

The pic, powering only the Critical loads from batteries and not AC Loads too.

Brilliant move for i.e. smaller batteries, or don’t want to use the batteries to heat a geyser on AC Loads using the batts for example.

Need to have a Carlo Gevazzi OR running with AC-Out_2 wired to non-Critical loads.

So how does it work exactly?
Does it ditch AC out 2?
Does it stop the battery from assisting upstream loads at specific SOC?
Or both?
Or are you guessing like me?

All it does is it limits the amount of power fed to the loads on the input side to only that which is available from PV. The battery is only discharged for critical loads.

The main reason is that if the 3kW geyser turns on at 11PM… you don’t want the battery to be discharged for that. But if there is 2kW of PV at noon, you want that to be fed to the geyser.

There is a similar feature in the Sunsynk.


I’m making an educated guess:
No Grid available

  1. Battery =/above X% SOC. AC2 = ON
  2. Battery below X% SOC. AC2 = OFF

Grid available

  1. Battery =/above X% SOC. AC2 = ON (from battery)
  2. Battery below X% SOC. AC2 = ON (from Grid)

Thanks, for clarifying, please check my understanding now.


  1. No Grid = AC2 out off & Input side loads all off.

  2. With Grid previous = AC2 out On & Input side loads fed by PV, Batteries and grid ( Priority set by user).

  3. With Grid (Only critical loads) = During Day: AC2 out ( non-essentials loads) are on & Input side loads (also non-essentials) only fed by excess PV and Grid.
    (Battery prioritized before load at a certain SOC?)

During Night AC2 out on & Input side (non-essentials), loads are only fed by Grid.

You can quickly see the devil is in the details.

@Phil.g00, that is exactly what I understood.

Thank you to all involved … and “Sunsynk”. (wicked smile) :wink:

I can see this being a long derailment. Maybe a thread split is necessary.
This development is quite fundamental to DB and load distribution in terms of priorities and will be referenced many times in the future.

What goes in which zone 1-4 & why is that load best suited to that zone?

Grid -------zone1--------CarloG--------zone2--------MultiP-------AC1out(zone3) OR ------AC2 out(zone4)

Why for instance would I chose zone 4 over zone 2 or vice versa? Or Zone 1 over Zone 2 or vice versa?
I think this needs some teasing out.

Simplify it … you have a smaller battery or actual issue, weeks of bad Cpt weather.

Grid — CarloG — MultiP — AC_Out1 (… or no Carlo, using AC_Out2 to power Non-Critical Loads)

So what do you do before this?
You have NodeRED running i.e. "weak attempt at “AI”, resulting in mostly manual intervention.

Now you can set it to run as Plonk described … and “walk away”, optimal savings daytime, with just powering the “controlled” Critical loads draw when Eskom is on … or set it to Keep Charged and use more Eskom.

Big array, a big battery … fewer weather issues … then you don’t need it.

It’s 23:51, so I will keep it short.

With this option set to “All system loads”, the default, it works as it always has. It will take power out of the battery to power anything anywhere in your setup (even on the input side), because it wants to save you the most money possible and make the grid import as low as possible.

With the option set to “Only critical loads”, it will only take energy out of the battery for loads on the output side. But if there is PV available, it will gladly allow the PV to power loads that are not critical.

The really short answer is: This ensures that we don’t use the battery to heat your geyser in the evening, but we do use the PV to heat it during the day.

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Thread is now split and titled as per Victron “title”.

@plonkster - Do we have a Pin Post feature on the forum? It would be good to PIN a post with the “correct/closest” answer…

So I am a ways off here… Someone add/correct me please :wink:

Yes! Absolutely brilliant!