Remove co-firing power plant and CHP

[mabijkerk]

Background
The model contains a coal power plant and a CHP with co-firing of biomass.

To be specific, 50% wood pellets are used and 50% coal. This percentage cannot be adjusted. Say that a user wants to set a coal power plant of 1 GW with 75% biomass, then there are currently three options available:

1. Set 1 GW of pulverized coal capacity and set the share of biocoal (torrefied biomass pellets) used by coal plants to 75%
2. Set 250 MW of pulverized coal capacity and 750 MW of biomass capacity.
3. Set 1 GW of puliverized coal with co-firing and the share of biocoal used by coal plants to 50%.

Goal
It is clear from the options outlined above, that option 3 is the least straightforward. For simplicity of the model, I therefore propose to remove the co-firing plants. This way, option 1 and 2 are still available to users, but we no longer have to maintain two plants that have no added value. We also remove at least to sliders from the model!

@quintel/core let me know if you have any reservations about this!

To do

• ETDataset: delete co-firing plants where relevant, check if any pipelines need to be updated to allow a share of biomass for regular coal plants in the start year
• ETLocal: delete co-firing plants where relevant
• ETEngine: determine how to migrate existing scenarios with co-firing plants
• ETSource: delete co-firing plants where relevant
• ETModel: delete co-firing plants where relevant

[timgassmann]

Actually I think the current "co-firing" categories in ETM do have added value, since it can be made very transparent in a scenario which part of the coal power plant capacity is conventional and which one is (partly) fired with another energy carrier - in this case biomass / biocoal (in reality there a specific existing coal power plant units which are adjusted to dire biomass while others remain firing conventional fossil coal). The only actual current limitation is that the co-firing percentage is set to a fixed percentage (50/50) whereas as a use you would want to be flexible in choosing the biomass percentage in a range between 0% and 100% for co-firing power plants. This way we can keep on distinguishing correctly in ETM between coal power plants that have been repurposed to fire another carrier and renewable biomassa plants which are often small (decentrally located) units and have a different operation compared to the large units. Could such an additional parameter for co-firing power plants, to set the percentage of biomassa in the mix - be added? Or repurpose the existing ETM "biocoal share" parameter which currently applies generically to all coal power plant types in ETM?

[mabijkerk]

Thanks for the input @timgassmann.

Or repurpose the existing ETM "biocoal share" parameter which currently applies generically to all coal power plant types in ETM?

You then mean that the biocoal slider should only apply to coal power plants that enable co-firing?