40 C.F.R. § 600 app II to Part 600

Current through March 31, 2024

Appendix II to Part 600 - Sample Fuel Economy Calculations

(a) This sample fuel economy calculation is applicable to 1978 through 1987 model year automobiles.

(1) Assume that a gasoline-fueled vehicle was tested by the Federal Emission Test Procedure and the following results were calculated:

HC = .139 grams/mile

CO = 1.59 grams/mile

CO₂ = 317 grams/mile

According to the procedure in § 600.113-78 , the city fuel economy or MPG_c, for the vehicle may be calculated by substituting the HC, CO, and CO₂ grams/mile values into the following equation.

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MPG_c = 27.7

(2) Assume that the same vehicle was tested by the Federal Highway Fuel Economy Test Procedure and calculation similar to that shown in paragraph (a) by this appendix resulted in a highway fuel economy or MPG_h of 36.9. According to the procedure in § 600.113 , the combined fuel economy (called MPG_c/h) for the vehicle may be calculated by substituting the city and highway fuel economy values into the following equation:

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(b) This sample fuel economy calculation is applicable to 1988 and later model year automobiles.

(1) Assume that a gasoline-fueled vehicle was tested by the Federal Emission Test Procedure and the following results were calculated:

HC = .139 grams/mile.

CO = 1.59 grams/mile.

CO₂ = 317 grams/mile.

(2) Assume that the test fuel used for this test had the following properties:

SG = 0.745.

CWF = 0.868.

NHV = 18,478 Btu/lb.

(3) According to the procedure in § 600.113-08 , the city fuel economy or MPG_c, for the vehicle may be calculated by substituting the HC, CO, and CO₂ gram/mile values and the SG, CWF, and NHV values into the following equation:

MPG_c = (5174 * 10⁴ * CWF * SG) / [((CWF * HC) + (0.429 * CO + (0.273 * CO₂)) ((0.6 * SG * NHV) + 5471)]

Example:

MPG_c = (5174 * 10⁴ * 0.868 * 0.745) / [(0.868 * .139 + 0.429 * 1.59 + 0.273 * 317)(0.6 * 0.745 * 18478 + 5471)]

MPG_c = 27.9

(4) Assume that the same vehicle was tested by the Federal Highway Fuel Economy Test Procedure and a calculation similar to that shown in (b)(3) of this section resulted in a highway fuel economy of MPG_h of 36.9. According to the procedure in § 600.210-08(c) or § 600.210-12(c) , the combined fuel economy (called MPG_comb) for the vehicle may be calculated by substituting the city and highway fuel economy values into the following equation:

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40 C.F.R. 600 app II to Part 600

51 FR 37852, Oct. 24, 1986, as amended at 71 FR 77958, Dec. 27, 2006; 76 FR 39570, July 6, 2011