Vintages for storage processes - unable to understand experience

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Hello,

I have a model for some storage processes that looks like the screenshot attached.

SREF22 and SREFCCS22 both produce commodities that need additional LNG to turn them back into ELC (in Sector_Fuels). The price of LNG is increasing in the model. So at some point SREF22 and SREFCCS22 become less economical than HESYS22, which doesn't require LNG to turn its output back to ELC.

I had initially defined HESYS22 and STGLION17 as vintaged, and SREF22 and SREFCCS22 as non-vintaged because only the former two have changing parameters. I saw the model exclusively deploy SREF22, SREFCCS22 and STGLION17, but not HESYS22. But as soon as I made SREF22 and SREFCCS22 vintaged (and that is the only change I made), the model started deploying HESYS22 at a reasonable time when HESYS22 is more economical than SREF* processes, and the results look much more logical.

Could you please explain why HESYS22 was not deployed when SREF* were not vintaged? Do vintages work differently for storage processes and am I missing something?

Thanks.