question

gr1pen avatar image
gr1pen asked

Dynamic ESS Idle Battery

I have reconfigured my Cerbo GX to use the Node Red Dynamic ESS.

However I dont get how Battery Idle is calculated? I find my battery in Idle state very often and using grid instead of battery, when battery use would be much cheaper and preferred.

For example setpoint can be negative (sell to grid) but battery is idle, so its not selling to grid or using battery.

Have I missed something here?

ESS
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4 Answers
steve0564 avatar image
steve0564 answered ·

Nearly same to me here!

Batterie's soc is nearly 90% in the morning because battery was idle the whole night, so it could not be filled with pv-energy for the day, because it's full.

On the other side battery is set idle even when the gridprice is very high (yesterday 0,77€ at 7 PM).

What's going wrong here?


configuration:

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1694503652101.png (40.8 KiB)
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Dirk-Jan Faber (Victron Energy) avatar image
Dirk-Jan Faber (Victron Energy) answered ·

We've just published a new release, that is more incorporated into the Venus OS and follows the target SOC instead of setting a setpoint and a less than ideal way of idling the battery.

As this uses a different approach, you will need to:
- update Venus OS (to 3.10 or above)
- update the victron-dynamic-ess node to version 0.1.1
- update the example flow
- reconfigure the Dynamic ESS node (as we switched from the site ID to the VRM portal ID)

More information can be found in the release notes and readme.

So please update first. If problems persist, you can file an issue here.

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Joe avatar image
Joe answered ·

Hi all,


I am on the latest FW including the dynamic ESS now officially. (3.31)

Facing the same isse: during day time, it's either idle or selling all the energy into the grid. During night time, I am consuming own battery until it is empty.
The system does NOT switch to "let's first load the battery, as the outlook is bad, no sun tomorrow" nor does it charge the battery during cheap ours.
Dynamic ESS simply seems to concentrate on "sell as much as possible into the grid".

I think I have set up everything correctly, attached some screens:

1714989832416.png

1714989863418.png

Charging of battery only happened when I turned off dynamic ESS, now it's turned on again.

1714989785204.png


Even worse: during daytime, it wants me to purchase energy (red)

1714990104015.png

The system correctly recognizes it's more expensive to BUY energy than SELLING it. So why is it selling everything w/o charging the battery first?

1714989955728.png

1714990007959.png

I have also recognized on the console, that the "target SOC" is a dynamic value, seems to be updated from time to time ( I can't change it!) - as I have 63% right now I understand it's selling to the grid, but as we have a rainy day and bad outlook for tomorrow, paired with high prices, I would expect to get the battery charged first before selling everything? w/o dynamic ESS I have a target SOC of 100% and a minimum SOC of 20%. Battery life is off.


1714990231169.png

Any idea what I am missing?


Thanks in advance!


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1714989863418.png (66.1 KiB)
1714989955728.png (69.2 KiB)
1714990007959.png (111.4 KiB)
1714990104015.png (82.2 KiB)
1714990231169.png (57.5 KiB)
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Joe avatar image
Joe answered ·

Guess I found the reason and want to share it with the community.

In the VRM portal, there is a (new? Did not recognize before!) option if you want to run the system in "green" or "trade" mode.


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The system was set to "trade"-mode which explains the behaviour of draining the battery.

After setting the operation mode to "Green mode" it works as expected.


1715326890869.png (34.4 KiB)
1715326989444.png (66.8 KiB)
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