§ 431.345 Energy conservation standards and effective dates. ( a ) Each compressor that is manufactured starting on January 10, 2025 and that: ( 1 ) Is an air compressor,
( 2 ) Is a rotary compressor,
( 3 ) Is not a liquid ring compressor,
( 4 ) Is driven by a brushless electric motor,
( 5 ) Is a lubricated compressor,
( 6 ) Has a full-load operating pressure greater than or equal to 75 pounds per square inch gauge (psig) and less than or equal to 200 psig,
( 7 ) Is not designed and tested to the requirements of The American Petroleum Institute standard 619, “Rotary-Type Positive-Displacement Compressors for Petroleum, Petrochemical, and Natural Gas Industries,”
( 8 ) Has full-load actual volume flow rate greater than or equal to 35 cubic feet per minute (cfm), or is distributed in commerce with a compressor motor nominal horsepower greater than or equal to 10 horsepower (hp),
( 9 ) Has a full-load actual volume flow rate less than or equal to 1,250 cfm, or is distributed in commerce with a compressor motor nominal horsepower less than or equal to 200 hp,
( 10 ) Is driven by a three-phase electric motor,
( 11 ) Is manufactured alone or as a component of another piece of equipment; and
( 12 ) Is in one of the equipment classes listed in the Table 1, must have a full-load package isentropic efficiency or part-load package isentropic efficiency that is not less than the appropriate “Minimum Package Isentropic Efficiency” value listed in Table 1 of this section. Table 1—Energy Conservation Standards for Certain Compressors
Equipment class
Minimum package isentropic efficiency
ηRegr(package isentropic efficiency reference curve)
d(percentage loss reduction) Rotary, lubricated, air-cooled, fixed-speed compressor
ηRegr + (1 − ηRegr) * (d/100)
−0.00928 * ln2 (.4719 * V1) + 0.13911 * ln(.4719 * V1) + 0.27110
−15 Rotary, lubricated, air-cooled, variable-speed compressor
ηRegr + (1 − ηRegr) * (d/100)
−0.01549 * ln2 (.4719 * V1) + 0.21573 * ln(.4719 * V1) + 0.00905
−10 Rotary, lubricated, liquid-cooled, fixed-speed compressor
.02349 + ηRegr + (1 − ηRegr) * (d/100)
−0.00928 * ln2 (.4719 * V1) + 0.13911 * ln(.4719 * V1) + 0.27110
−15 Rotary, lubricated, liquid-cooled, variable-speed compressor
.02349 + ηRegr + (1 − ηRegr) * (d/100)
−0.01549 * ln2 (.4719 * V1) + 0.21573 * ln(.4719 * V1) + 0.00905
−15
( b ) Instructions for the use of Table 1 of this section: ( 1 ) To determine the standard level a compressor must meet, the correct equipment class must be identified. The descriptions are in the first column (“Equipment Class”); definitions for these descriptions are found in § 431.342.
( 2 ) The second column (“Minimum Package Isentropic Efficiency”) contains the applicable energy conservation standard level, provided in terms of package isentropic efficiency.
( 3 ) For “Fixed-speed compressor” equipment classes, the relevant Package Isentropic Efficiency is Full-load Package Isentropic Efficiency. For “Variable-speed compressor” equipment classes, the relevant Package Isentropic Efficiency is Part-load Package Isentropic Efficiency. Both Full- and Part-load Package Isentropic Efficiency are determined in accordance with the test procedure in § 431.344.
( 4 ) The second column (“Minimum Package Isentropic Efficiency”) references the third column (“ηRegr”), also a function of full-load actual volume flow rate, and the fourth column (“d”). The equations are provided separately to maintain consistency with the language of the preamble and analysis.
( 5 ) The second and third columns contain the term V1, which denotes compressor full-load actual volume flow rate, given in terms of cubic feet per minute (“cfm”) and determined in accordance with the test procedure in § 431.344.
[85 FR 1591, Jan. 10, 2020]