Manufacturers may generate credits applicable to the CO2 fleet average program described in § 86.1865-12 by implementing specific air conditioning system technologies designed to reduce air conditioning refrigerant leakage over the useful life of their passenger automobiles and/or light trucks (including MDPV); only the provisions of paragraph (a) of this section apply for non-MDPV heavy-duty vehicles. Credits shall be calculated according to this section for each air conditioning system that the manufacturer is using to generate CO2 credits.
EQUATION 1 TO PARAGRAPH (B)(1)
Where:
MaxCredit is 12.6 (grams CO2 -equivalent/mile) for air conditioning systems using HFC-134a, and 13.8 (grams CO2 -equivalent/mile) for air conditioning systems using a refrigerant with a lower global warming potential.
LeakScore means the annual refrigerant leakage rate determined according to paragraph (a) of this section. If the calculated rate is less than 8.3 grams/year (or 4.1 grams/year for systems using only electric compressors), the rate for the purpose of this formula shall be 8.3 grams/year (or 4.1 grams/year for systems using only electric compressors).
GWPREF means the global warming potential of the refrigerant as indicated in paragraph (e) of this section or as otherwise determined by the Administrator.
HiLeakDis means the high leak disincentive, which is determined using the following equation, except that if GWPREF is greater than 150 or if the calculated result of the equation is less than zero, HiLeakDis shall be set equal to zero, or if the calculated result of the equation is greater than 1.8 g/mi, HiLeakDis shall be set to 1.8 g/mi:
EQUATION 2 TO PARAGRAPH (B)(1)
Where:
LeakThreshold = 11.0 for air conditioning systems with a refrigerant capacity less than or equal to 733 grams; or LeakThreshold = [ Refrigerant Capacity * 0.015] for air conditioning systems with a refrigerant capacity greater than 733 grams, where Refrigerant Capacity is the maximum refrigerant capacity specified for the air conditioning system, in grams.
EQUATION 3 TO PARAGRAPH (B)(2)
Where:
MaxCredit is 15.6 (grams CO2 -equivalent/mile) for air conditioning systems using HFC-134a, and 17.2 (grams CO2 -equivalent/mile) for air conditioning systems using a refrigerant with a lower global warming potential.
LeakScore means the annual refrigerant leakage rate determined according to paragraph (a) of this section. If the calculated rate is less than 10.4 grams/year (or 5.2 grams/year for systems using only electric compressors), the rate for the purpose of this formula shall be 10.4 grams/year (or 5.2 grams/year for systems using only electric compressors).
GWPREF means the global warming potential of the refrigerant as indicated in paragraph (e) of this section or as otherwise determined by the Administrator.
HiLeakDis means the high leak disincentive, which is determined using the following equation, except that if GWPREF is greater than 150 or if the calculated result of the equation is less than zero, HiLeakDis shall be set equal to zero, or if the calculated result of the equation is greater than 2.1 g/mi, HiLeakDis shall be set to 2.1 g/mi:
EQUATION 4 TO PARAGRAPH (B)(2)
Where:
LeakThreshold = 11.0 for air conditioning systems with a refrigerant capacity less than or equal to 733 grams; or LeakThreshold = [ Refrigerant Capacity * 0.015] for air conditioning systems with a refrigerant capacity greater than 733 grams, where Refrigerant Capacity is the maximum refrigerant capacity specified for the air conditioning system, in grams.
EQUATION 5 TO PARAGRAPH (C)(1)
Where:
Leakage = the CO2 -equivalent leakage credit value in grams per mile determined in paragraph (b) of this section, subject to the maximum values specified in paragraph (c)(2) of this section.
Production = The total number of passenger automobiles or light trucks, whichever is applicable, produced with the air conditioning system to which to the leakage credit value from paragraph (b)(1) or (2) of this section applies.
VLM = vehicle lifetime miles, which for passenger automobiles shall be 195,264 and for light trucks shall be 225,865.
Table 1 to Paragraph (c)(2) -Maximum Leakage Credit Values
[g/mile]
Model year | Passenger automobiles | Light trucks |
2027 | 11.0 | 13.8 |
2028 | 8.3 | 10.3 |
2029 | 5.5 | 6.9 |
2030 | 2.8 | 3.4 |
40 C.F.R. §§86.1867-12