Fix reserve margin constraints

[idelder]

This makes two fixes:

1. The r1r2 index should be used when summing up reserve contributions for exchange. the r index was erroneously used inside reserve_margin_dynamic
2. If one region commits firm capacity on an exchange technology (intertie), then that firm capacity should be subtracted from its own reserve margin contributions, as that is less power it can commit to its own demands. See Issue Bug in reserve margin constraint #265. Request eyes on this. ❗

Summary by CodeRabbit

• Bug Fixes
  • Improved reserve margin calculations for inter-region power exchanges by correctly handling both import and export directions in reserve margin computations, resulting in more accurate system reserve assessments.

[coderabbitai]

Warning

Rate limit exceeded

@ParticularlyPythonicBS has exceeded the limit for the number of commits that can be reviewed per hour. Please wait 24 minutes and 33 seconds before requesting another review.

⌛ How to resolve this issue?

After the wait time has elapsed, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans have higher rate limits than the trial, open-source and free plans. In all cases, we re-allow further reviews after a brief timeout.

Please see our FAQ for further information.

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Pro

Run ID: 939b5a42-7ebb-486f-8b1f-70ef94780da3

📥 Commits

Reviewing files that changed from the base of the PR and between 0d47b50 and ea6ae3b.

📒 Files selected for processing (1)

• temoa/components/reserves.py

Walkthrough

The change modifies reserve margin calculations in temoa/components/reserves.py to bidirectionally handle exchange technologies. Previously, only imports (where r2 == r) were considered; now both imports and exports (where r1 == r) are handled. Exchange-specific keys (r1r2) now replace destination/source region keys in reserve derate, capacity derate, and related calculations.

Changes

Cohort / File(s)

Summary

Reserve Margin Exchange Handling temoa/components/reserves.py

Modified reserve_margin_dynamic and reserve_margin_static to bidirectionally handle exchange technologies. Updated logic to compute contributions when r2 == r (imports) and subtract when r1 == r (exports). Changed public data flow to use exchange-specific keys (r1r2) for reserve derate, capacity derate, and capacity_to_activity calculations. Refactored control flow to iterate over exchange pairs and update available capacity or credit by region-direction.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely summarizes the main changes: fixing reserve margin constraints through bidirectional exchange handling and proper accounting of firm capacity commitments.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[SutubraResearch]

this looks great to me