Adding material commodities to existing processes

[MCodet]

Hello, first time posting in the forum !

I have several questions regarding the addition of new commodities to existing processes. The context is that I am trying to add material commodities as inputs for power generation processes, as well as for fuel production (specifically fuels used in the power sector: coal, gas, biogas...).These material commodities are aggregates, which are composed of individual material commodities (aluminum, copper...). The image below is an example for gas power plants.


Here are my questions:

•  For power generation processes, I want the material inputs to be factors of the installed capacity in GW. To do so, I used "ENV_CAP"/"NCAP_COM" in a TFM_INS. I have never used it, and therefore don't know how it works. Can it only be used with ENV commodities (when used as "ENV_CAP") or for new capacities (when used as "NCAP_COM") ? Also, I used a "top_check" column to specify that the new commodities are inputs of power generation processes, but I'm not sure this is the correct method.
  

• For fuel production processes, I want the material input to be a factor of the quantity of fuel used in the power system. To do so, I want to add an commodity to the "FT_ELC..." processes for fuel-fired power generation technologies. However, I don't want the current input parameters to be disrupted by this addition. Can I represented like the image below, without precising a "Share-I" ? I want the FT_ELCNGA process to still choose among its input commodities GASBFG, GASGWG, GASNGA, GASRFG, as it did before, but also compell it to use 1 unit of material aggregate as a mandatory commodity. If not, is there a specific attribute I should be using ? I went through the "times and veda attributes" list without finding one that would match what I want to do.
  

Let me precise that I don't want the material commodities to be defined as ENV commodities, because I want to model their supply chain upstream (see the diagrams I attached to this message).

Thank you in advance,
Marie

[Antti-L]

> I used "ENV_CAP"/"NCAP_COM" in a TFM_INS. I have never used it, and therefore don't know how it works. Can it only be used with ENV commodities (when used as "ENV_CAP") or for new capacities (when used as "NCAP_COM") ? Also, I used a "top_check" column to specify that the new commodities are inputs of power generation processes, but I'm not sure this is the correct method.

As there is no such attribute as ENV_CAP in TIMES, I would suggest not to use that if using TIMES. You can use NCAP_COM for any capacities (old or new), and as you can see from the documentation, it can be used for defining capacity-related input/output flows, and it has the 'IO' index for specifying whether it is an input or an output flow. Therefore, nothing needs to be added to the topology, and no top_check should be used unless you have indeed defined the flows in the topology. The capacity-related input/output commodities can be of any type. However, note that NCAP_COM defines an input/output flow for every year over the lifetime of the capacity. If wishing to define a material flow occurring only once (when the capacity is installed) and not every year, use NCAP_ICOM instead.

You could use ACT_FLO (or Input in VEDA) for defining an input flow of MATGASFUEL to be 1 unit of MATGASFUEL per 1 unit of process activity. EFF is not possible to use here (but ACT_EFF(MATGASFUEL) would be possible). You could also use FLO_EFF for defining flow-specific material consumptions.

[MCodet]

Thank you so much for the explanations, I will try this !