Add multi-metrics for RA

[abdelrahman-ayad]

Summary

• This PR expands the use of Resource Adequacy metrics to use a multi-metrics approach. Users can select one or more metric (EUE, LOLH, NEUE, or a combination) with a corresponding threshold to be used in stress periods selection.
• An upcoming PR will extend the available stress metrics to assess duration, frequency, and magnitude of shortfalls.

Technical details

Implementation notes

• EUE is no longer used for determining the shoulder periods in function get_houlder_periods(), in case EUE is not defined as a stress metric
• If EUE is not included as a stress metric, PRAS-informed PRM update is blocked, and fixed-increment update is used, similar to setting GSW_PRM_UpdateMethod=1

Switches added/removed/changed

• GSw_PRM_StressThreshold -> GSw_PRM_StressThresholdMetrics: This switch now defines the / delimited stress metric switches to be used for evaluation. For each Metric, a dedicated switch is added to define the HierarchyLevel, Criterion, and the PeriodAggMethod. Current tested metrics are EUE, LOLH, and NEUE.

• GSw_PRM_StressThresholdEUE: Switch to define the EUE stress metric hierarchy, threshold, and PeriodAggMethod.

• GSw_PRM_StressThresholdLOLH: Switch to define the LOLH stress metric hierarchy, threshold, and PeriodAggMethod.

• GSw_PRM_StressThresholdNEUE: Switch to define the NEUE stress metric hierarchy, threshold, and PeriodAggMethod.

Metric	Switch	Definition	RA dimension	Example
LOLH	GSw_PRM_StressThresholdLOLH	Expected (average) count of event-hours/year experiencing shortfall. It is expressed in terms of event-hours	Frequency	transgrp_2.4_sum: The LOLH threshold is set at 2.4 events-hour/year, aggregated using sum over transgrp
EUE	GSw_PRM_StressThresholdEUE	Expected (average) total energy shortfall over the study period, expressed in energy units (MWh per year)	Energy	transgrp_10000_sum: The EUE threshold is set at 10000 MWh over the study period, aggregated using sum over transgrp
NEUE	GSw_PRM_StressThresholdNEUE	Normalized expected (average) total energy shortfall over the study period expressed in parts-per-million (ppm)	Energy	transgrp_1_sum: The NEUE threshold is set at 1 ppm aggregated using sum over transgrp

Relevant sources or documentation

Slides deck reviewing Resource Adequacy multi-metrics:
RA multi metrics slides deck

Validation, testing, and comparison report(s)

Comparison report

To check

• Pacific (EUE, LOLH, NEUE, EUE/NEUE/LOLH)
• USA_defaults (EUE, LOLH, NEUE, EUE/NEUE/LOLH)

Checklist for author

Details to double-check

• Included comparison reports for appropriate test cases
• Documentation updated if necessary
• Code formatting standardized
• Reusable functions used where possible instead of copy/pasted code

General information to guide review

• Zero impact on results of default case
• No large data file(s) added/modified
• No substantive impact on runtime for full-US reference case
• No substantive impact on folder size for full-US reference case
• No change to process flow (runreeds.py, reeds/core/solve/solve.py)
• No change to code organization
• No change to package requirements (environment.yml or Project.toml)

Did you use LLM tools (chatbot or copilot) in the preparation of this PR? If so, describe how

• I used Claude to plan the changes in runreeds.py and stress_periods.py

[patrickbrown4]

This is cool, thanks! I haven't gone all the way through stress_periods.py yet, but adding some interim comments. My main thoughts are:

1. I would call it LOLH instead of LOLE if the units are event-hours
2. I think it would simplify the processing to drop the third argument of the compound GSw_PRM_StressThreshold{LOLE|EUE|NEUE} switches; instead of leaving it up to the user, NEUE- and EUE-based thresholds would always add stress periods with the highest EUE, and the LOLH-based threshold would always add stress periods with the highest LOLH. (When we add the depth-based metric, it would always add stress periods with the highest peak outage MW.)

[patrickbrown4]

We don't use the national NEUE within the model so it can be removed (sorry for all the cruft). You would also remove the following blocks. It's kind of a lot though, and it's not directly related to this PR, so it might be best to save for a followup cleanup PR.

ReEDS/postprocessing/bokehpivot/reeds2.py

Lines 2764 to 2775 in ce7c0d5

	('Resource adequacy',
	{'file':'neue.csv',
	'columns': ['year', 'iteration', 'neue'],
	'index': ['year', 'iteration'],
	'preprocess': [
	{'func': pre_neue, 'args': {}},
	],
	'presets': collections.OrderedDict((
	('Normalized expected unserved energy [%]', {'x':'year', 'y':'neue', 'chart_type':'Bar', 'explode':'scenario', 'bar_width':'1.75'}),
	)),
	}
	),

ReEDS/postprocessing/bokehpivot/reports/templates/reeds2/standard_report_expanded.py

Line 57 in ce7c0d5

{'name': 'NEUE (ppm)', 'result': 'Resource adequacy', 'preset': 'Normalized expected unserved energy [%]'},

ReEDS/postprocessing/compare_cases.py

Line 196 in ce7c0d5

'NEUE (ppm)',

All the 'NEUE (ppm)' keys in reedsplots.plot_diff() like

ReEDS/reeds/reedsplots.py

Line 117 in ce7c0d5

'NEUE (ppm)': 'NEUE',

ReEDS/reeds/reedsplots.py

Lines 486 to 490 in ce7c0d5

	if val == 'NEUE (ppm)':
	neue_threshold = float(sw.GSw_PRM_StressThresholdNEUE.split('_')[1])
	ymax = max(ymax, 10, neue_threshold*1.05)
	ax[0].axhline(neue_threshold, c='C7', ls='--', lw=0.75)
	ax[1].axhline(neue_threshold, c='C7', ls='--', lw=0.75)

[patrickbrown4]

Thanks, happy to discuss any of these if helpful (particularly the one about dropping GSw_PRM_StressThresholdEUE). Could you re-request a review when I should take another look?

[patrickbrown4]

The default GSw_PRM_StressStorageCutoff is still EUE_0.1, which looks like it means the default shoulder-period functionality would be removed with this change.

I think we should keep the original EUE formulation in get_shoulder_periods(). It should apply for both GSw_PRM_StressThresholdEUE and GSw_PRM_StressThresholdNEUE (both of which use EUE to select stress periods).

I'm not sure if it should apply to GSw_PRM_StressThresholdLOLH-identified periods. If it does, I think it's fine to still use EUE to identify those shoulder periods. If that complicates things, you can just drop the shoulder functionality for LOLH-identified periods (but keep it for the NEUE-/EUE-identified periods).

[patrickbrown4]

Can you remind me, do any of the regions you reviewed formulate their RA target as EUE [MWh] instead of NEUE [ppm]? EUE MWh would be a bit of a weird threshold in the context of load growth, and a single number wouldn't really make sense to apply across different transgrp regions with different loads (as is specified in the default value).

So I guess my feeling is that it might be simpler just to drop GSw_PRM_StressThresholdEUE and stick with NEUE and LOLH as the two options. What do you think?

[abdelrahman-ayad]

Some regions (e.g., SPP had EUE seasonal targets and The Tri-State Agency had <0.5 GWh, and ERCOT (magnitude) of 19 GW). Nevertheless, I agree that NEUE makes it easier to implement across multiple regions with different load profiles etc. I'll remove the EUE for now and we can always return it in a future update.

[patrickbrown4]

Included in #124