TFM_AVA and User Constraint

[vangelis]

Dear all,

When a process is excluded via TFM_AVA but at the same time it participates in a User-Defined Constraint, then the User-Defined Constraint still considers this process and remains active. I expected that the User constraint would have been eliminated for the periods for which the process is unavailable.

This behavior could lead to infeasibilities or to other inconsistencies in the model.

I do not know if this is because I forgot to define something else additional to the TFM_AVA to prevent this situation or other users have experienced a similar issue.

Best,

Vangelis

[AKanudia]

If you reimport the scenario with this UC after eliminating the process via AVA, it will go away. In fact, you should have seen a $170 for this process... Are you sure that the process went away?

[vangelis]

Hi Amit,

If I do not explicitly define the years for which the UC is active to be the same as the years for which all processes participating in this UC are active, then the UC is exported to TIMES without the eliminated process. This sometimes can alter the initial meaning of the constraint: consider for example a UC of the form Capacity(A)=Capacity(B), but if B is eliminated then the UC becomes Capacity(A)=0.

Thus, I would like to ask you if there is an elegant way to instruct VEDA-FE not to export this UC to TIMES for those periods for which the eliminated process is not considered, e.g. in a TFM_AVA like structure.

Once again thank you very much for your help,

Vangelis

[AKanudia]

I would request Antti to comment on this. While I can see how what you want could be desirable in the example you give, I don't see how this can be generalized. There could be 'n' processes in a constraint, each with its own period of availability. Would you want the constraint to be active when *all* processes are active?

At the very least, this will have to be an explicit choice, as unavailable processes turning off constraints could lead to a lot of confusion in general.

[vangelis]

I fully agree that if such a feature is to be included in a future release it should be included as an explicit choice of the user and not as a general approach, since it is context-dependent.

Thanks a lot,
Vangelis