Appendix A     A.1 
 APPENDIX  B 
 
Emissions Estimates  
 
Emissions reductions were estimated by the California Air Resources Board ( CARB ) by 
estimating baseline emissions under  two separate scenarios: (1) business -as-usual 
(BAU) , and (2) comparing the BAU emissions to the expected lower emissions as a 
result of the U.S. Environmental Protection Agency’s ( U.S. EPA ) Significant New 
Alternatives Policy ( SNAP ) Rules  prohibiting certain high -global warming potential 
(GWP ) hydrofluorocarbons  (HFCs ) in new and retrofitted refrigeration equipment.  
 
The emissions under both scenarios were estimated using the peer -reviewed 
methodology used i n the annual greenhouse gas ( GHG ) emissions inventory produced 
by CARB for the emissions sector “Ozone -depleting Substances Substitutes .”   
 
The emissions estimates methodology is summarized in the 2015 Edition of “California’s 
High Global Warming Potentia l Gases Emission Inventory - Emission Inventory 
Methodology and Technical Support Document” (CARB 201 6a).  Additional descriptions 
of the methodology are in the 2016 edition of the CARB GHG Inventory Technical 
Document (CARB 2016 b), and in Gallagher, et al ., 2014.  
 
The only emission factor change is the global warming potential (GWP) of the 
refrigerant s used in retrofits and new equipment , which  had been lowered as a result of 
the SNAP Rule s.  Although equipment refrigerant charge sizes, annual leak rates, and 
end-of-life refrigerant loss rates could theoretically change , these emissions factors 
have been kept the same to show only the effects of the SNAP refrigerant prohibitions.  
Estimating future changes in charge sizes, leak rates, and end -of-life loss r ates is 
beyond the scope of this analysis.  
 
The following table lists the emissions factors used to estimate HFC emissions and 
potential reductions.  (Table shown on separate page.)  Appendix B                 B.2 
  
Summary Table B1: Estimated Emissions Reductions from  the Proposed Regulation  
SNAP Sector  Sub-sector Used for Emissions 
Reductions Calculations (if 
applicable)  Equipment 
Units in CA, 
2017  Average 
Lifetime in 
Years  Number of 
New Units 
Annually  Average  
Charge 
(amount) of 
F-gas in lbs.  Average  
Annual 
Leak (loss) 
Rate  Average 
Loss Rate 
at End -of-
Life 
Commercial Refrigeration - 
Retail Food  Rule 20 Retail Food Refrigeration - 
Large Equipment (2,000 lbs. +)  650 15 45 3,635  18%  20%  
  Rule 20 Retail Food Refrigeration - 
Medium Equipment (200 - 2,000 
lbs.)  18,000  15 800 704 23%  20%  
  Rule 20 Retail Food Refrigeration - 
Small Equipment (50 -200 lbs.)  59,000  20 2,000  122 19%  20%  
Rule 20 Remote Condensing 
Units    320,000  20 8,100  31 15%  34%  
Rule 20 Stand -alone (Self -
contained) Refrigeration    630,000  20 32,000  7 0.3%  98.5%  
Rule 20 Vending Machines    470,000  15 36,000  0.7 0.3%  98.5%  
Rule 20 Retrofit Existing R -22 
Supermarkets    1,800  7.5 74 3500  21%  20%  
Rule 20 Retrofit Existing R -
404A Supermarkets    1,800  10 79 3500  21%  20%  
Rule 20 Retrofit Existing R -22 
Grocery Stores    400 7.5 78 1400  21%  20%  
Rule 20 Retrofit Existing R -
404A Grocery Stores    400 10 82 1400  21%  20%  
Rule 21 Refrigerated Food 
Processing and Dispensing 
Equipment)    43,000  12 3,500  3 0.3%  98.5%  
Rule 20 Foam End -Use 
Sectors   > 20 million  
cubic 
meters  30 - 50 300,000 cubic 
meters  (m3) 7 lbs per m3 1% 15%  
  Appendix B                 B.3 
 Summary Table B1 (continued ) 
SNAP Sector (repeated 
from previous page)  Sub-sector Used 
for Emissions 
Reductions 
Calculations (if 
applicable)  Baseline 
Refrigerant 
(pre -SNAP 
Rule)  GWP of 
Baseline 
Refrigerant  Refrigerant 
Post-SNAP 
Rule  GWP of 
Post-SNAP 
Refrigerant  Baseline 
Emissions 
Per Unit, 
Per Year 
(MTCO 2E) Post -SNAP 
Emissions 
Per Unit, 
Per Year 
(MTCO 2E) Emissions 
Reductions 
Per Unit, 
Per Year 
(MTCO 2E) Total Emissions 
Reductions all 
New Units, Each 
Year of 
Operation 
(MTCO 2E) 
Commercial Refrigeration 
- Retail Food  Large Equipment 
(2,000 lbs. +)  R-404A  
R-407A  3015  R-407A,  
R-448A,  
R-449A  1627  961 519 442 19,910  
  Medium 
Equipment (200 - 
2,000 lbs.)  R-404A  
R-407A  3015  R-407A,  
R-448A,  
R-449A  1627  234 126 108 86,282  
  Small Equipment 
(50 - 200 lbs.)  R-404A  
R-407A  3015  R-407A,  
R-448A,  
R-449A  1627  33 18 15 30,724  
Remote Condensing Units    R-404A  3922  R-407A  2107  9 5 4 34,523  
Stand -alone (Self -
contained) Refrigeration    HFC-134a,  
R-404A,  
R-507,  
R-600a  2394  HFC-134a,  
R-448A,  
R-449A,  
R-600a  982 0.4 0.2 0.2 7,496  
Vending Machines    HFC-134a  1430  R-600a  3.3 0.03  0.0001  0.03  1,120  
Retrofit Existing R -22 
Supermarkets    R-22 1810  R-448A  
R-449A  1391  680 523 157 11,723  
Retrofit Existing R -404A 
Supermarkets    R-404A  3922  R-448A  
R-449A  1391  1,432  508 924 72,891  
Retrofit Existing R -22 
Grocery Stores    R-22 1810  R-448A  
R-449A  1391  272 209 63 4,893  
Retrofit Existing R -404A 
Grocery Stores    R-404A  3922  R-448A  
R-449A  1391  573 203 370 30,424  
Refrigerated Food 
Processing and 
Dispensing Equipment)    R-404A  3922  R-448A  
R-449A  1391  0.5 0.2 0.3 1,026  
Foam End -use Sectors   Low-GWP 
(various)  1 - 5 Low-GWP 
(various)  1 - 5 <0.1  <0.1  0 (zero)  0 (zero)  
Total Reductions/year   per operating yr.                301,010  Appendix B                 B.4 
 Table B2.  Reductions (MMTCO 2E) each calendar year, shown by equipment production year for all emissions 
sectors covered by proposed regulation  
 
 Emissions Reductions (All Covered Emissions Sectors): Calendar Year  
Production Year 
Below 2018  2019  2020  2021  2022  2023  2024  2025  2026  2027  2028  2029  2030  
2018  0.29 0.29 0.29 0.29 0.29 0.29 0.29 0.29 0.29 0.29 0.29 0.29 0.29 
2019   0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 
2020    0.32 0.32 0.32 0.32 0.32 0.32 0.32 0.32 0.32 0.32 0.32 
2021     0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 
2022      0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 
2023       0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 
2024        0.35 0.35 0.35 0.35 0.35 0.35 0.35 
2025         0.36 0.36 0.36 0.36 0.36 0.36 
2026          0.36 0.36 0.36 0.36 0.36 
2027           0.36 0.36 0.36 0.36 
2028            0.37 0.37 0.37 
2029             0.37 0.37 
2030              0.37 
Maximum Annual 
Reductions  0.29 0.59 0.92 1.26 1.61 1.97 2.32 2.68 3.04 3.40 3.76 4.13 4.50 
Est. Overlap w/ Kigali 
Phasedown  0% 25% 25% 25% 25% 25% 25% 25% 25% 25% 25% 25% 25% 
Adjusted Annual 
Reductions  0.3 0.4 0.7 0.9 1.2 1.5 1.7 2.0 2.3 2.5 2.8 3.1 3.4 
Table Notes:  The annual reductions from all emissions sectors are aggregated for each production year.  The results are estimated emission s 
reductions per year.  D ue to the additive nature of emissions reductions achieved by each year of lower -GWP equipment operation, the reductions 
begin to accumulate greater than 301,000 MMTCO 2E emissions reductions annually (0.3 million metric tonnes of CO 2-equivalent [MMTCO 2E]) by the 
year 2030.  Potential emissions reductions also increase due to the annual growth rate of new equipment manufactured for use in California, which is 
correlated to the population growth rate of 0.75 percent annually through 2030 (C alifornia  Department of Finance  2017). Emissions reductions can 
occur from more than one reduction me asure, and the same reductions could be double -counted if not corrected.  
 Appendix B        B.5 
 Adjustments to Emissions Reductions - Avoiding a Double -Count  of the Same Reductions : 
 
Emissions reductions estimates are very sensitive to the initial assumptions used.  To 
estimate HFC emissions reductions as a result of the regulations described in this Initial 
Statement of Reasons ( ISOR ), we modeled emissions from new and retrofit equipm ent 
following the regulation requirements, and compared the emissions to BAU emissions 
without the regulations.  The emissions reductions results were 4.5 MMTCO 2E annually by 
2030.  
 
CARB then modeled the estimated lower emissions in a new BAU baseline scen ario that 
would result from implementation of the “Kigali Amendment” global phase -down in the 
production and consumption of HFCs, if the United States were to follow the agreement 
made October 15, 2016  (CARB 2017c) .  Adding the effects of the HFC phase -down 
resulted in lower BAU emissions estimates.  CARB again modeled the HFC reductions 
from the proposed regulation and compared them to the new BAU that included the HFC 
phase -down.  In this scenario, the HFC emissions reductions that were above and beyond 
the BAU with the HFC phase -down were estimated to be  up to  3.4 MMTCO 2E annually by 
2030.  The new estimate reflects the 25 percent “overlap” in reductions achieved by the 
phase -down and by the proposed regulation (CARB 2017 c).   
 
Fewer reductions (from BAU)  occur when the Kigali phase -down is added to the baseline 
BAU, because the phase -down would begin to reduce the average GWP of HFCs used in 
new equipment and retrofits.  A given piece of equipment can only be manufactured to use 
low-GWP one initial time.  To avoid double -counting the same emissions reductions, those 
reductions from the Kigali Amendment HFC phase -down were counted first, followed by 
any added emissions reductions from the proposed regulation in this ISOR.   
 
The following Kigali Amendment p hase -down schedule for developed countries, including 
the United States, is provided for reference (UNEP 2016).  
 
Table B3.  The Kigali Amendment HFC Phase -down Schedule for Developed 
Countries.  
 
Year  Production/Consumption 
Cap  (relative to baseline)  Reductions in 
Production/Consumption  
2017 -2018  None  None  
2019  90% 10% 
2024  60% 40% 
2029  30% 70% 
2034  20% 80% 
2036  15% 85%