Cyclic Condition - Consecutive Temporal Blocks

[aporrasc]

This is related to issue #1238, but with a different configuration.

I now have one temporal block for investments and three consecutive temporal blocks.

I would like to impose the cyclic constraint per temporal block and, if possible, max_cumulated_flows only on some specific units in each temporal block.

However, I have discovered that with this configuration, the cyclic constraint is not satisfied. Have I done something wrong? If I understand correctly, the current implementation of the cyclic condition and the node_state_variable require historical time intervals, and that is the case.

Any ideas, suggestions, or advice?

[Tasqu]

@aporrasc I'm curious how exactly is this failing. Is the model not running? Is it infeasible? Or is it just not behaving as expected? As far as I can tell, a continuous structure like this should result in something, but it might not be what you're expecting.

Looking at the constraint_cyclic_node_state_indices function, what it seems to do is constrain the last time slice of a temporal_block relative to the the time slice immediately before the first time slice of the same block. In this case, it should e.g. limit the end of 2040 based on the last step of 2030, which at least to me sounds wrong in any case. I guess this constraint was originally written to bind the "initial value" (i.e. the first history time slice) based on the last time slice.

@DillonJ @datejada @nnhjy @nhniina @gnawin @manuelma Is there a reason we don't simply constrain the first and last time slices of the temporal_block respective to one another? Why do we include the "initial_value" time slice as an extra step?

In my opinion, a more elegant solution would be to make the entire temporal block loop if a cyclic_condition is applied to it. E.g. make it so that t_before_t(t_after=<first time slice>) -> <last time slice>. In principle, this should handle more complex cases like unit minimum startup/shutdown times or connection delays as well. However, it might not be realistic to apply changes of this magnitude for now, as I don't think this would be a simple change.