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Hi, I want to add a constriant on minimum heat supply by district heating for the residential heat demand. Enclosed I am sending a copy of relevant TIMES-VEDA tables as your reference. The user-constriant that I have built is non-binding. Could you please let me know what is wrong in my tables? Thank you in advance. Best regards, AkramS
Welcome to the ETSAP TIMES Forum! On the basis of my quick look at your constraint, it looks like it is defining a constraint on the minimum use of RESHXC101, RESHXC102, RESHXC103 by the RHB* processes, in proportion to the total commodity production of these three commodities. Thus, it would not be too binding if those RESHX* commodities are in fact being mostly used by those RHB* processes. But the constraint would become clearer to me if you could post a screenshot of the UC_FLO and UC_COMPRD attributes generated by VEDA-FE for this constraint (from the Browser). As your question actually appears to be more related to VEDA-FE than to TIMES, you might also consider posting such questions on the VEDA Forum.
Thanks Antti-L for your quick reply! Yes, you are right. Enclosed I am sending the attributes from the Browser. Could you please help me to fix this user-constriant? Best regards, Akram
Ok, thanks, looking at your screenshot, the constraint does indeed appear to be formulated just as I initially thought. But as you ask to help for fixing it, it seems that you would like to formulate it in some way differently?  Could you thus write down in algebraic terms the formulation you actually want for the constraint, and then I could perhaps try to help with changing the UC constraint specification accordingly?
I want to define minimum district heat penetration in the residential sector for the heat demand. The way that I thought was correct (very simple) and tried to include in the UC-table: "Heat supply by disrict heating" + "Heat supply by individual boilers" = "Heat demand in the residential sector" "Heat supply by district heating" >= 30% of "Heat demand in the residential sector" Thanks for your help!
Yes, I understand the desired condition "Heat supply by district heating" >= 30% of "Heat demand in the residential sector". But how should you measure "Heat demand in the residential sector"?  I guess it could probably be measured by the residential demand for space heating and hot water, do you think so?  But which commodities represent these demands?  Do the RDEM101, RDEM102, etc. represent those demands, i.e. demand for residential space heating and hot water?  If so, you could define the UC_COMPRD coefficients for those demand commodities in the constraint specification, instead of RESHXC101, RESHXC102, RESHXC103, for which you are now defining the UC_COMPRD. You can define UC_COMPRD for the demand commodities by moving the UC_FLO specification to a separate row in the ~UC_T table, and keep your original Pset_Set,  Pset_PN and Cset_CN on that row for the UC_FLO. In principle, the efficiency of the district heating heat exchangers should then also be taken into account, but that would be only a small refinement.
Enclosed please see the revision I did in the ~UC_T table. I 'm not sure I understood your explanation correctly. Sorry!
In your new screenshot you are still defining UC_COMPRD exactly on the same commodities as before, but now you try to define UC_FLO on RDEM* without any process mask. I cannot see how it could possibly work that way.  I was suggesting completely different (UC_COMPRD for the demands, and keeping UC_FLO as it was). I don't understand the logic in your model, but you do. Therefore, it should be easy for you to define the UC_COMPRD coefficients for the correct "Heat demand in the residential sector", and the UC_FLO coefficients on the  "Heat supply by district heating".   As you could see from your earlier screenshot, you were defining the UC_COMPRD for the RESHXC101, RESHXC102, RESHXC103 commodities. If the sum of these commodities is not the "Heat demand in the residential sector", then the constraint is wrong, and you should correct it.  Because I don't know which are the correct commodities that DO represent the "Heat demand in the residential sector", I cannot really tell you which they are. Only you know which they are, and so you just need to define the UC_COMPRD for them.
Now it seems that I understood your explanation. Enclosed please see the latest version of the ~UC_T table. I modified the penetration level as well. I checked the results. The percentage of district heating of total heat demand was correct Rolleyes .
I am glad to hear that.  Shy (Note that on the first two rows you don't need to put anything under Pset_Set and Pset_PN, so I would suggest to leave those four cells blank.)
Thank you so much for your help!