Gams 23.5.1 -general Algebraic Modeling System-... [portable] File
The energy system models (used by the IEA and national governments) were heavily optimized for the GAMS 23.x branch. Recalibrating these models for a newer GAMS release can cost months of validation time.
For those searching for "GAMS 23.5.1 download" or setup guidance, here are the technical specifications: GAMS 23.5.1 -General Algebraic Modeling System-...