DESS bug report

Q&A and troubleshooting
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1

  1. Solar forecast differs from ESS to DESS. The ESS forecast is updated more frequently then the DESS forecast and therefore more accurate.

    ESS-Screenshot_2024-11-27_12-11-26
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    DESS-Screenshot_2024-11-27_12-12-10
    DESS-Screenshot_2024-11-27_12-12-101048×457 57.6 KB

  2. Settings/DynamicEss/Schedule/*/Strategy should be 1 in green mode which is not always the case and forces the system to buy energy even when solar power is available.

Strategy

From 3.30~7 there are currently 2 different strategies in use:

  • 0 - Follow the target SOC
  • 1 - Minimize grid usage / maximize battery usage

The system determines which of the strategies is best to follow during a specific hour, mainly, but not limited to, looking at price. Usage of these restrictions has been added to the importable flows.

FYI: v3.51~3 + Node-Red, but I do not use node-Red DESS + @dognose HACK

2

This has nothing to do with the selected mode. (trade vs green)

both strategies (0=targetsoc; 1=self consume/regular ESS) exist within trade and green mode, depending on the desired outcome.

therefore…

is intended in green mode at certain times:

  • Charging for later usage at cheaper grid prices.
  • Charging above solar to ensure battery balancing

If you don’t want this to happen, you can enable “charge from grid restrictions” in VRM (Settings → Dynamic ESS):

image
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You can also define a schedule for that:

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s

Something like “Yes, restrict it from 8 - 16, when solar is expected” and only allow it during night, when grid prices are cheap for sure. (In Case you are using dynamic tarifs)

3

thx @dognose for explaining.

although usablility has great potential.

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Do the battery restrctions differ for weekdays and weekends? => No

DESS_restrict_weekdays
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?!?

4

Ah, tiny error in the caption there :slight_smile: Took me a while to spot.

5

to clarify the bug report @dfaber:

  1. Settings/DynamicEss/Schedule/*/Strategy should be 1 in green mode in the actual hour of the schedule. If this is not the case it forces the system to buy energy for consumtion even when solar power is available and battery is almost full.

workaround and proof: (from 06:02 to approx 20:00 do not buy anything)

root@cergbogx:~# crontab -l
# minute stunde day_of_the_month month day_of_the_week
02 6-19 * * * /home/root/bin/fake_DynamicEss_Strategy.sh

root@cerbogx:~# cat /home/root/bin/fake_DynamicEss_Strategy.sh
#!/bin/bash

for i in {0..11}
do
/usr/bin/dbus -y com.victronenergy.settings /Settings/DynamicEss/Schedule/${i}/Strategy SetValue 1 >/dev/null
done

If you look at Settings/DynamicEss/Schedule/*/Start using dbus-spy you could figure out which is the actual hour by using the command:

root@cerbogx:~# date -d @1732784400
Thu Nov 28 09:00:00 UTC 2024

If you have changed Strategy to 1 the system takes a few moments to realize and stops consuming energy from the grid as supposed in green mode.

6

There is a difference between Strategy and Operating Mode. Operating Mode is set in VRM, strategy is the chosen strategy for the hour by the algorithm.
It can be that the algorithm choose the wrong strategy and we can look into why it did that.