CO2 emissions accounting - issue with emissionsperPlant for CCS plants

[dharik13]

In branch syn_fuel_model_addition_new_csc, The current formulation inaccurately accounts for the emissions from point sources with carbon capture. See explanation below.

Issue

Emissions_power.jl

• Line 33-37: Emissions for power plant is being defined based on parameter dfGen[!,:CO2_per_MWh][y] that is defined in load_generators_data.jl (lines 196-204) to be fuel_CO2_intensity x heat rate. If we set the same fuel type for CCGT-CCS and CCGT, then both CCGT-CCS plant will have higher CO2 emissions than CCGT, that will be reflected in the expression eEmissionsByZone that is used in the emissions cosntraints

Emissions_Hsc.jl
• Line 37-49: same issue as above for emissions_power. SMR with CCS is treated to have higher emissions than SMR once the fuel type is changed.

For emissions budget constraints in the various files
(co2_cap_power_hsc.jl, co2_cap_hsc.jl, co2_cap_power.jl), the equation is generally of the form:

Emissionsby zone <= some limit determined by other parameters where the LHS is computed as sum of respective expressions related to emissions from power, HSC and CSC MINUS emissions from DAC. However, we are not accounting for emissions captured for individual technologies on the LHS.

Proposed fix

• Add a column to generators_data and HSC_generators_data to specify CO2 capture rate for each technology.
• When computing emissions per plant in emissions_power, emissions_HSC, account for capture rate, so that the resulting expressions actually reflect the physically correct values
• To avoid inputing multiple parameters related to capture rates, eliminate parameters CCS_tonne_per_tonne in HSC_generators_data.csv and CCS_tonne_per_MWh in generators_data.csv respectively. Once we know the capture rate and CO2 generated from fuel combustion (fuelc_cO2 x time heat rate) we can compute the capture rate in the model.

[shakesy94]

I am not sure I understand why emissions_power.jl and emissions_hsc.jl are fundamentally wrong. I think the issue is more that the emissions constraint does not account for captured CO2. If the captured CO2 term defined here is added to the balance, this should solve the issue. Am I missing something?

[dharik13]

This has been fixed in branch "bioenergy_CSC" branch. Will be merged with main when CO2 supply chain is added.