USEPA/flowsa

Split of HFCs leaves uncharacterized "Others"

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WesIngwersen commented

flowsa/flowsa/data_source_scripts/EPA_GHGI.py

Line 782 in 4cf2593

def split_HFCs_by_type(fba, source_dict, **_):

This fxn works to speciate the "HFCs and PFCs" in T_4_102 based on the breakdown in T_4_100, but this leaves the "Others" flows
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These "Others" flows do not get characterized later. The CO2e of these Others is not-negligible - it is 9% of these ODS Substitutes CO2e in 2016 and 10% in 2017

bl-young commented

That's correct, and consistent with the NGHGIAM in excel. I think that is the main source of "lost" HFCs (along with the skipped Aerosols, Fire Protection, and Solvents)

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WesIngwersen commented

I agree that it was lost before, but i think we should add it in as its included in the GHGI. An option is to assigned it a proxy species

Here is some language from the GHGI 2022 4-137

Others represent an unspecified mix of HFCs and PFCs, which includes HFC-152a, HFC-227ea, HFC-245fa, HFC-365mfc, HFC-43-10mee, HCFO-1233zd(E), HFO-1234yf, HFO-1234ze(E), HFO-1336mzz(Z), C4F10, and PFC/PFPEs, the latter being a proxy for a diverse collection of PFCs and perfluoropolyethers (PFPEs) employed for solvent applications. For estimating purposes, the GWP value used for PFC/PFPEs was based upon C6F14.

I don't think it implies that all the Others use the C6F14 CF, but C6F14 could potentially be used as a proxy.

Would there be another option of including the CO2e from these Others like perhaps using a CO2e flowable?

bl-young commented

Two immediate options that come to mind are to either:

  • map "Others" to something in the FEDEFL (we don't really have a great non-specific flow)
  • or to keep_unmapped_flows: True to just leave it in the final FBS. Note the context and units would be different if there is no mapping:
Flowable Class SectorProducedBy SectorConsumedBy SectorSourceName Context Location LocationSystem FlowAmount Unit FlowType Year
HFC-125 Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 1722.324 kg ELEMENTARY_FLOW 2016
HFC-134a Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 6210.874 kg ELEMENTARY_FLOW 2016
HFC-143a Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 810.8729 kg ELEMENTARY_FLOW 2016
HFC-236fa Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 17.03279 kg ELEMENTARY_FLOW 2016
HFC-32 Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 875.92 kg ELEMENTARY_FLOW 2016
Others Chemicals 211111   NAICS_2012_Code air 0 FIPS 0.001915 MMT CO2e ELEMENTARY_FLOW 2016
bl-young commented

Ah yes saw your edit - we could do a generic CO2e flowable and add that to the flow list (per bullet 1 above)

WesIngwersen commented

HFCs and PFCs, unspecified perhaps with a MTCO2e unit?

bl-young commented

Yes I like that idea if you are ok with that flow.

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bl-young commented

The units is going to be a challenge - mass units with CO2e is not a valid unit.

Could we call the flow HFCs and PFCs, unspecified (CO2e) and use units of kg?

I'm working on hfcs branch of fedelemflowlist

  • 👍1
bl-young commented

Will look something like this, pending final name:

Flowable Class SectorProducedBy SectorConsumedBy SectorSourceName Context Location LocationSystem FlowAmount Unit FlowType Year
HFC-125 Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 1,722 kg ELEMENTARY_FLOW 2016
HFC-134a Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 6,211 kg ELEMENTARY_FLOW 2016
HFC-143a Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 811 kg ELEMENTARY_FLOW 2016
HFC-236fa Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 17 kg ELEMENTARY_FLOW 2016
HFC-32 Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 876 kg ELEMENTARY_FLOW 2016
HFCs and PFCs, unspecified Chemicals 211111   NAICS_2012_Code emission/air 0 FIPS 1,915 kg ELEMENTARY_FLOW 2016