Bug: Type mismatch in unit_cost_explorer.py causes KeyError at runtime

[coderabbitai[bot]]

Description

A type mismatch bug was identified in temoa/utilities/unit_cost_explorer.py at line 128 that will cause a KeyError at runtime.

Problem

The call to StorageEnergyUpperBound_Constraint passes '1' (string) for the time-of-day parameter, but the model initializes M.time_of_day with integers (line 103: range(1, tod_slices + 1)). This type mismatch will cause a KeyError when the constraint attempts to index M.V_StorageLevel[r, p, s, d, t, v] at line 258 of temoa/components/storage.py.

Location

Primary Issue:

• File: temoa/utilities/unit_cost_explorer.py
• Line: 128
• Current: StorageEnergyUpperBound_Constraint(M, 'A', 2020, 'winter', '1', 'battery', 2020)
• Should be: StorageEnergyUpperBound_Constraint(M, 'A', 2020, 'winter', 1, 'battery', 2020)

Secondary Issue:

• File: temoa/components/storage.py
• Line: 207
• The type hint for parameter d should be changed from str to int to reflect actual usage

Impact

• Runtime KeyError when executing the unit cost explorer script
• Type hints don't reflect actual expected types, causing confusion and type-checking issues

References

• PR #165: https://github.com/TemoaProject/temoa/pull/165
• Comment: https://github.com/TemoaProject/temoa/pull/165#discussion_r2438054845
• Requested by: @ParticularlyPythonicBS