Commodity Aggregation

[Hesam]

Hi,

I am doing a commodity aggregation, which involves excluding a portion of a commodity flow. The aggregated commodities encompass transport fuels, including TRADST. However, I intend to exclude the portion of TRADST that is directed into TRABUNK. I would appreciate your guidance on whether I have introduced this correctly, as attached. 

   

Best,

[Antti-L]

Firstly, COM_AGG operates on commodity aggregates only (VAR_COMPRD / VAR_COMNET).  One thus cannot define COM_AGG for some process.
Secondly, TRADST is apparently a commodity, but what is TRABUNK?  The picture does not include TRABUNK at all, but a process named TRA_Bunk.
Thirdly, COM_AGG operates on the NET amounts, unless the COM_LIM is defined as FX, or the commodity type is DEM.  If you want aggregation of PRD amounts, you should bear that in mind. (You can allow overproduction also for FX commodities, if needed.)

If TRABUNK is a commodity, representing the amount to be excluded from TRADST, then your table would be in principle ok, if you just remove the PSet_PN and Top_Check columns, and add a −1 row for TRABUNK.  If TRABUNK is not a commodity, you could easily create it and define e.g. FLO_EMIS(r,y,TRA_Bunk,TRADST,TRABUNK,ANNUAL)=1.  However, I would probably myself use some different approach e.g. based on using solely FLO_EMIS for aggregating TRAFINOIL, instead of using COM_AGG, due to the FX requirement. COM_AGG was originally implemented specifically with emissions in mind, and so aggregating just the NET amounts was made the default.

[Hesam]

Sorry, TRA_BUNK is a process name and I want to exclude that part of TRADST that goes to TRA_BUNK. I did not introduced that and I wanted just to modify it. Then, considering your first point, is it possible to modify this entry?

[Antti-L]

If all the commodities have LimType = FX, then the original aggregation does work (but one should remove the PSet_PN and Top_Check columns). If not, it does not work correctly. Assuming it did work before adding the exclusion, then you can add the exclusion either by 1) introduce a new commodity and exclude it by a −1 row, or 2) just add a negative TRAFINOIL output flow to the TRA_Bunk process.

[Antti-L]

> Then, considering your first point, is it possible to modify this entry?

Sorry, if my answer was not explicit enough. The explicit answer is YES.  But only VAR_COMPRD / VAR_COMNET can be aggregated with COM_AGG.  Individual process flows can be added to or subtracted from the derived aggregate VAR_COMPRD by using e.g. FLO_EMIS.

[Hesam]

Dear Antti,
Thank you for your clarification. I will make the adjustments as suggested and reach out if I require further assistance.

Best,

[Hesam]

> Then, considering your first point, is it possible to modify this entry?

Sorry, if my answer was not explicit enough. The explicit answer is YES.  But only VAR_COMPRD / VAR_COMNET can be aggregated with COM_AGG.  Individual process flows can be added to or subtracted from the derived aggregate VAR_COMPRD by using e.g. FLO_EMIS.

Dear Antti,

I initially defined the dummy commodity as the attachment. However, I had a question regarding whether it should be classified as an ENV or NRG commodity. It essentially functions as a virtual energy commodity, and its unit should align with an energy unit. Interestingly, when I labeled it as an ENV commodity with PJ units, there was no recorded output for the commodity after running the model. Yet, when I defined it as an NRG commodity with PJ units, I did observe output results for VAR_ComprdM associated with the commodity. Unfortunately, I encountered an issue with VEDA, which was not able to add the commodity unless I did start from scratch.

   

Subsequently, I incorporated FLO_EMIS into the Trans file of the primary file that describes the COMMAGG, as indicated attached. I also conducted the aggregation as we previously discussed. However, I noticed that there hasn't been any alteration in TRAFINOIL, nor have there been deductions due to the inclusion of the dummy. I would appreciate your assistance in this matter. Furthermore, I am curious whether it would be feasible to introduce the dummy commodity as an auxiliary commodity. Your additional clarification would be valued.

   
   

Best,

[Antti-L]

It should best be an ENV commodity, with default LimType (of course not FX for a dummy), because then you would not need any Topology entry for it.  I don't see how it would be possible that you would not see any output for it; there would definitely be output for it if there is input of TRADST to the TRA_Bunk process. If you still say that you don't see the output, please provide a reproducible case.

Note also that the FLO_EMIS does not need any IE option, and it does not support LimType.

[Antti-L]

Just to clarify the LimType issue:  You were defining the dummy commodity with LimType = FX.  That however does not work here, because LimType = FX would mean that the commodity balance is fixed, requiring that Production = Consumption.  Because you have no consumption for that dummy, that cannot work. Therefore, in the FI_Comm table, leave the LimType empty, and define the dummy as ENV.  Using NET for the aggregation is in this case perfectly fine, because there is no consumption.

It should thus be very simple: Just define the dummy flow with a FLO_EMIS (like you did in your picture, but remove the AllRegions~0 and LimType columns), and then add the dummy commodity into the COMAGG table (like you did already).  No need to made any (other) changes into the Tra_Bunk process, and so there is no need to add the dummy into the process topology at all.

[Hesam]

Just to clarify the LimType issue:  You were defining the dummy commodity with LimType = FX.  That however does not work here, because LimType = FX would mean that the commodity balance is fixed, requiring that Production = Consumption.  Because you have no consumption for that dummy, that cannot work. Therefore, in the FI_Comm table, leave the LimType empty, and define the dummy as ENV.  Using NET for the aggregation is in this case perfectly fine, because there is no consumption.

It should thus be very simple: Just define the dummy flow with a FLO_EMIS (like you did in your picture, but remove the AllRegions~0 and LimType columns), and then add the dummy commodity into the COMAGG table (like you did already).  No need to made any (other) changes into the Tra_Bunk process, and so there is no need to add the dummy into the process topology at all.

Dear Antti,

Yesterday, I did all of them. Then, after synchronization, I received a notification indicating that the process filter for the FLO_EMIS Excel table has not been applied. In response to this, I just replaced the process column (Pset_PN, if I recall correctly), and the notification didn't reappear after synchronization. Upon inspecting the item details module, I found that the commodity had been defined, and there was a COMAGG table for the commodity, but the FLO_EMIS table was missing.

I was thinking of using this in a simple model. Alternatively, I could introduce the dummy using an activity constraint.

Best,

[Antti-L]

> I incorporated FLO_EMIS into the Trans file of the primary file that describes the COMMAGG.

In a Subres Transformation file, one can only define attributes for processes that are defined in that Subres. If your FLO_EMIS seems to  be ignored, your TRA_Bunk process is apparently not defined in that Subres. You could define the FLO_EMIS in any regular scenario, or even SysSettings.