Description of expected Inverter operation for each batpred mode

[sparkyhughes]

In the plan that Batpred creates and executes, there are several difference scenarios. It would be good to see these modes documented and the expected operation of the Inverter/battery.

I’m using Solar Assistant with a Growatt inverter and it would be good to clarify the expected operation so that I can properly configure the service which executes that. Some are easy to understand, others not so.

For example:
Export - easy to understand, export battery down to the target SOC

Freeze Export (usually seen during the day) - Does this match the “discharge_freeze_service”? my current setup does not charge the battery with excess solar, is this expected? What I see here is that if the house load is higher than solar (ie we have a wash on or dishwasher etc) then I’m importing from the grid on peak rate. Maybe my inverter mode is wrong here?. The target SOC in the plan stays the same for that block of Freeze Exporting so it looks like Batpred wants to keep the battery at the same SOC level and export as much solar as possible, even if we periodically import from the grid if cloudy and an appliance is on.

Charge Freeze - is this to stop charging from both grid and solar? Or just grid?

from the above you can see I’m after some clarification so that I can properly configure the Service API stuff in apps.yaml.

[WyndStryke]

A lot of this is down to how the inverters are configured in Apps.yaml.

These are my personal notes on the modes, however this is for the Fox inverter not Solar Assistant so "your mileage may vary". Also I am not guaranteeing that I've correctly understood them all!

# Predbat statuses versus Fox work-modes
#
# PREDBAT           FOX
# Demand (Eco)      Self-Use
# This is the default, the load will be covered by solar and/or battery. Excess solar will
# charge the battery or be exported if the battery is full. This is described as 'Eco' Mode
# for GivEnergy inverters but other inverters use different terminology.
#
# Charging          Force Charge
# The battery charges from the grid and the grid also covers any load. Solar power will
# also be used to charge the battery.
#
# Freeze charging   Back-up (with reserve soc set to number.min_soc_on_grid)
# The battery is charging but the current battery level (SoC) is frozen (held). Think of
# it as a charge to the current battery level. The grid or solar covers any house load. 
# If there is a shortfall of Solar power to meet house load, the excess house load is met
# from grid import, but if there is excess Solar power above the house load, the excess 
# solar will be used to charge the battery,
#
# Hold charging     Back-up (with reserve soc set to number.min_soc_on_grid)
# A type of charge where the target SoC % is the same as the current SoC %, effectively the
# same as a charge freeze (but without being explicitly selected).
#
# No Charge         Self use
# A charge where the target SoC % is lower than the current battery SoC level so there will
# be no charging unless the usage is unexpectedly high.
#
# Exporting         Force Discharge 
# The battery is being force-discharged. The house load will be covered by the battery and
# any excess is exported to the grid. Any solar generated will be exported.
#
# Freeze exporting  Feed-in First 
# The battery is in demand mode, but with charging disabled. The battery or solar covers the
# house load. As charging is disabled, if there is excess solar generated, the current SoC
# level will be held and the excess solar will be exported. If there is a shortfall of
# generated solar power to meet the house load, the battery will discharge to meet the extra
# load.
#
# Hold exporting    Self use
# The plan was to force export but the minimum battery level was reached and thus the battery
# is kept in Demand mode. If the battery level again gets above the threshold it will be changed
# back to Export mode.
#
# Calibration       Needs an automation
# Fox inverters do not automatically calibrate, so to do this an automation is needed if required.
# At least once every 7 days the battery should hit the 100% SoC mark.  This can be done by setting
# the predbat min_keep, etc as needed if too much time has passed. 
#
# Error
# If there is a configuration error or other problem, you should check the Predbat log file for more
# details.

[sparkyhughes]

That’s a good start, like you say, specific to inverters so is good to get a discussion to clarify the expected operation of the inverter and battery setup regardless of the make/model. I think some things in the plan (like the textual description of the plan) reference the GivEnergy modes as this was the first supported inverter.

From a growatt perspective we have:
Battery First
Load First
Grid First

and target SOC % for charge and discharge for these. It’s mostly working ok for my setup but I think further improvements can be made.

[gcoan]

It would be good to see these modes documented and the expected operation of the Inverter/battery

This is already included in the predbat documentation https://springfall2008.github.io/batpred/what-does-predbat-do/