This section describes a compliance approach for trailers that is consistent with the modeling for vocational vehicles and tractors described in § 1037.520 , but is simplified consistent with the smaller number of trailer parameters that affect CO2 emissions. Note that the calculated CO2 emission rate, eCO2, is equivalent to the value that would result from running GEM with the same input values.
Where:
Ci = constant values for calculating CO2 emissions from this regression equation derived from GEM, as shown in Table 1 of this section. Let C5 = 0.988 for trailers that have automatic tire inflation systems with all wheels, and let C5 = 0.990 for trailers that have tire pressure monitoring systems with all wheels (or a mix of the two systems); otherwise, let C5 1.
TRRL = tire rolling resistance level as specified in paragraph (b) of this section.
[DELTA]CdA = the [DELTA]CdA value for the trailer as specified in paragraph (c) of this section.
WR = weight reduction as specified in paragraph (d) or (e) of this section.
Table 1 of § 1037.515 -Regression Coefficients for Calculating CO2 Emissions
Trailer category | C1 | C2 | C3 | C4 |
Long dry box van | 76.1 | 1.67 | -5.82 | -0.00103 |
Long refrigerated box van | 77.4 | 1.75 | -5.78 | -0.00103 |
Short dry box van | 117.8 | 1.78 | -9.48 | -0.00258 |
Short refrigerated box van | 121.1 | 1.88 | -9.36 | -0.00264 |
C1 = 76.1
C2 = 1.67
TRRL = 4.6 kg/tonne
C3 = -5.82
[DELTA]CdA = 0.7 m2
C4 = -0.00103
WR = 655 lbs
C5 = 0.990
eCO2 = (76.1 + 1.67 + (-5.82 ·0.7) + (-0.00103 ·655)) ·0.990
eCO2 = 78.24 g/ton-mile
Table 2 of § 1037.515 -Bin Determinations for Trailers Based on Aerodynamic Test Results
[[DELTA]CdA in m2]
If a trailer's measured [DELTA]CDA is . . . | Designate the trailer as . . . | And use the following value for [DELTA]CDA . . . |
[LESS THAN EQUAL TO]0.09 | Bin I | 0.0 |
0.10-0.39 | Bin II | 0.1 |
0.40-0.69 | Bin III | 0.4 |
0.70-0.99 | Bin IV | 0.7 |
1.00-1.39 | Bin V | 1.0 |
1.40-1.79 | Bin VI | 1.4 |
[GREATER THAN EQUAL TO]1.80 | Bin VII | 1.8 |
Table 3 of § 1037.515 -Weight Reductions for Trailers
[pounds]
Component | Material | Weight reduction (pounds) |
Structure for Suspension Assembly a | Aluminum | 280 |
Hub and Drum (per axle) | Aluminum | 80 |
Floor b | Aluminum | 375 |
Floor b | Composite (wood and plastic) | 245 |
Floor Crossmembers b | Aluminum | 250 |
Landing Gear | Aluminum | 50 |
Rear Door | Aluminum | 187 |
Rear Door Surround | Aluminum | 150 |
Roof Bows | Aluminum | 100 |
Side Posts | Aluminum | 300 |
Slider Box | Aluminum | 150 |
Upper Coupler Assembly | Aluminum | 430 |
a For tandem-axle suspension sub-frames made of aluminum, apply a weight reduction of 280 pounds. Use good engineering judgment to estimate a weight reduction for using aluminum sub-frames with other axle configurations.
b Calculate a smaller weight reduction for short trailers by multiplying the indicated values by 0.528 (28/53).
40 C.F.R. §1037.515