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Battery can discharge more than critical load during grid outage dispatch with AC losses #1058

@brtietz

Description

@brtietz

Describe the bug
A battery can discharge more power than the critical load during the grid outage dispatch when AC losses are present.
While the "battery to load" powerflow is correct, multiplying the current by the voltage gives a full-power discharge during these steps, lowering the SOC prematurely. A 5% AC loss turns into a 90% loss.

To Reproduce
Steps to reproduce the behavior:

  1. Open a PV+Battery case
  2. Set critical load to 100%
  3. Set an outage for the first 6+ hours of the year
  4. The battery fully discharges in <2 hours, despite the critical load supporting a 4-5 hour discharge

Attached SAM case demonstrates the error:
crit_load_discharge_error.zip

Expected behavior
Battery voltage times current should match critical load in steps like this. Extra discharged energy should be proportional to the AC loss.

Desktop (please complete the following information):

  • Version 2022.11.21, Develop

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