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pabou38 avatar image
pabou38 asked

ESS: a way to inject to the grid BEFORE the battery is fully charged ?

Hello ESS afficionados ..

I run an ESS with DC coupled PV (ie mppt). I know the mppt will first power load , then charge the battery and last, when battery full (and if configured), send the surplus to the grid.

Can you see a way to inject to the grid BEFORE the battery is fully charged ?

I also have an AC coupled PV on AC in side of the Multi, and a EV car charger (myenergy Zappy), which can grab the surplus to charge the car. There are instances when I would rather use the mppt power to charge the car, than to charge the battery (and would need this power to be injected rather than used by the Multi to charge the battery).


This is one the the MANY issue/headache/scratch my head thing when running ESS along side another (non victron) energy system !!

Thanks ESS lovers



ESS
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3 Answers
matt1309 avatar image
matt1309 answered ·

Hi @pabou38


There's a few ways to do this.

If you just want one off change, i would adjust grid setpoint setting in ESS settings on GX device.

If you want it automatic/based on conditions I believe most people setup their own configuration/requirements in node red to automatically adjust the grid setpoint to get the system to export to grid before battery is fully charged.

You can add your own custom logic to calculate the grid setpoint. ie

maybe you want battery to only be charged with 1000w then the rest is exported to grid.

or you all power to be exported after x percentage etc. The options are endless.


This may also be useful for you:

GitHub - victronenergy/dynamic-ess



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lifeingalicia avatar image
lifeingalicia answered ·

Like @matt1309 Node red or any automation / scripting that can read and post to modbus..

e.g. read in bat soc decide on max charging power or grid set point (I use Openhab)

Have fun





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matess4rs avatar image
matess4rs answered ·

Hi, I solved this by DVVC/Limit managed battery charge voltage. I have got Pylontech, changing from 50V to 51V. If you decrease voltage, part of energy goes to grid, and other part goes still to battery.

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