Pure process emissions

[JulStraus]

Problem statement

In the current state, we allow in a model for a node to have either pure energy related emissions through the type EmissionsEnergy or a combination of process and energy emissions through the type EmissionsProcess.

I think my original thought process was that energy related emissions would always be present when we have process emissions. However, when thinking a bit more about it, I realize that this is not necessarily the case. In a methanol plant based on natural gas, most of the carbon of the methane ends up in the product methanol. This is currently not possible to be modelled directly as the calculated energy related emissions (through the carbon content) would in this case always be higher than the actual emissions.

Potential solution

We can introduce a pure process dependent emissions type. As a consequence, I would argue that the new type should be called EmissionsProcess and the name of the existing type changed to EmissionsEnergyProcess.

Important

This change would be breaking as we change the behavior.
I do however think that it is still beneficial to do.

What are your thoughts @hellemo and @espenfb?