Title 40

SECTION 94.305

94.305 Credit generation and use calculation.

§ 94.305 Credit generation and use calculation.

(a) For each participating engine family, calculate THC + NOX and PM emission credits (positive or negative) according to the equation in paragraph (b) of this section and round emissions to the nearest one-hundredth of a megagram (Mg). Use consistent units throughout the calculation.

(b) Credits (Mg) for each engine family are calculated as: Emission credits = (Std - FEL) × (UL) × (Production) × (AvgPR) × (LF) × (10−6)


(i) Std = the applicable cycle-weighted marine engine THC + NOX or PM emission standard in grams per kilowatt-hour.

(ii) FEL = the family emission limit for the engine family in grams per kilowatt-hour. (The FEL may not exceed the limit established in § 94.304(m) for each pollutant.)

(iii) UL = the useful life in hours of operation.

(iv) Production = the number of engines participating in the averaging, banking, and trading program within the given engine family during the calendar year (or the number of engines in the subset of the engine family for which credits are being calculated). Quarterly production projections are used for initial certification. Actual applicable production/sales volumes are used for end-of-year compliance determination.

(v) AvgPR = average power rating of all of the configurations within an engine family, calculated on a sales-weighted basis, in kilowatts.

(vi) LF = the load factor, dependent on whether the engine is intended for propulsion or auxiliary applications, as follows:

(A) 0.69 for propulsion engines,

(B) 0.51 for auxiliary engines.

[64 FR 73331, Dec. 29, 1999, as amended at 68 FR 9786, Feb. 28, 2003]