Freeze export and pull from grid if energy is negatively priced?

[platplatypus]

Hi all,

This is a question about predbat's strategy for making the most out of a negatively priced energy session. I currently don't get paid for export so its quite simple case of normally charging the battery with solar, and using that for consumption. I noticed for tomorrow's negatively priced electricity, predbat's plan is to still charge the battery with solar and then just cruise past the negative session.

To me, it would be intuitive to freeze export at 06:00 and then charge from the grid at 12:30 when the energy is most negative. Is there something in the config that would encourage that behaviour?

something like this?

[gcoan]

In general, predbat should choose the most optimal plan, as you say, holding the battery level then charging on the negative import rate to generate a small amount of income

is switch.predbat_set_export_freeze turned on so Predbat can take advantage of export freeze? (and is it configured for your inverter in apps.yaml)

Is there something in the config that would encourage that behaviour?

difficult to tell without a debug log from when it was happening and your config

if the predbat plan isn't what you want you can always override it

suggest next time you see this happening you raise a new issue with the logfile and debug file for proper investigation

[platplatypus]

Thank you for the response. I can confirm that switch.predbat_set_export_freeze is turned on. What I'm a little bit uncertain about is the apps.yaml configuration. For context, I have a Sigenergy system and have been using the one in the documentation as is. So this section reads:

Services to control the inverter

charge_start_service:

• service: input_select.select_option
  entity_id: input_select.predbat_requested_mode
  option: "Charging"
  charge_stop_service:
• service: input_select.select_option
  entity_id: input_select.predbat_requested_mode
  option: "Demand"
  discharge_start_service:
• service: input_select.select_option
  entity_id: input_select.predbat_requested_mode
  option: "Discharging"
  charge_freeze_service:
• service: input_select.select_option
  entity_id: input_select.predbat_requested_mode
  option: "Freeze Charging"
  discharge_freeze_service:
• service: input_select.select_option
  entity_id: input_select.predbat_requested_mode
  option: "Freeze Discharging"

So apart from the freeze export nomenclature being different? I assume this is ok?
When I did manually override the half-slots manually, the behavior was in-line with expectations.

For getting a good logfile and debug file, is this a matter of enabling "debug enable" when such a slot comes up, or does it have to be done in advance?

[gcoan]

So apart from the freeze export nomenclature being different? I assume this is ok?
When I did manually override the half-slots manually, the behavior was in-line with expectations.

The SigEnergy integration to predbat works via a helper automation. In Predbat apps.yaml you configure what service calls predbat makes when it wants to set the inverter mode, the calls set a helper entity to the required mode, and then an automation kicks in to actually configure the inverter appropriately.

So you have everything setup correctly for predbat to freeze export.

For getting a good logfile and debug file, is this a matter of enabling "debug enable" when such a slot comes up, or does it have to be done in advance?

At any time when you see the right pattern of rates and predbat not acting as you expect, turn debug enable on, so predbat creates a debug file in the debug directory. You will need to rename it to .txt and then attach that to the github ticket alongwith the predbat logfile.
Or in the predbat web console there is an option to 'download debug', which will create the file and download it to your computer (doesn't work that well on on ipad unfortunately).

What we want to see is why predbat chooses the behaviour it does when evaluating the plan. The debug file and logfile will enable this to be analysed

[platplatypus]

Thanks, will do so next time. :)