II 

118TH CONGRESS 

2D SESSION S. 4389 

To amend the Internal Revenue Code of 1986 to promote the increased 

use of renewable natural gas, to reduce greenhouse gas emissions and 

other harmful transportation-related emissions that contribute to poor 

air quality, and to increase job creation and economic opportunity 

throughout the United States. 

IN THE SENATE OF THE UNITED STATES 

MAY 22, 2024 

Mr. TILLIS (for himself and Mr. WARNER) introduced the following bill; which 

was read twice and referred to the Committee on Finance 

A BILL 

To amend the Internal Revenue Code of 1986 to promote 

the increased use of renewable natural gas, to reduce 

greenhouse gas emissions and other harmful transportation-related emissions that contribute to poor air quality, and to increase job creation and economic opportunity throughout the United States. 

1 Be it enacted by the Senate and House of Representa2 tives of the United States of America in Congress assembled, 

3 SECTION 1. SHORT TITLE. 

4 This Act may be cited as the ‘‘Renewable Natural 

5 Gas Incentive Act of 2024’’. 


ssavage on LAPJG3WLY3PROD with BILLS
2 

•S 4389 IS

1 SEC. 2. INCREASED CREDIT FOR RENEWABLE NATURAL 

2 GAS. 

3 (a) IN GENERAL.—Section 6426 of the Internal Rev4 enue Code of 1986 is amended— 

5 (1) in subsection (a)(2), by inserting ‘‘and (l)’’ 

6 after ‘‘subsection (d)’’, and 

7 (2) by adding at the end the following new sub8 section: 

9 ‘‘(l) RENEWABLE NATURAL GAS FUEL CREDIT.— 

10 ‘‘(1) IN GENERAL.—For purposes of this sec11 tion, the renewable natural gas fuel credit is the 

12 product of $1.00 and the number of gallons of re13 newable natural gas or gasoline gallon equivalents of 

14 a nonliquid renewable natural gas sold by the tax15 payer for use as a fuel in a motor vehicle or motor16 boat, sold by the taxpayer for use as a fuel in avia17 tion, or so used by the taxpayer. 

18 ‘‘(2) RENEWABLE NATURAL GAS.—For pur19 poses of this section, the term ‘renewable natural 

20 gas’ means compressed or liquefied gas derived from 

21 biomass (as defined in section 45K(c)(3))— 

22 ‘‘(A) which was produced by a person reg23 istered under section 4101(a), and 

24 ‘‘(B) with respect to which the producer 

25 has made a certification described in paragraph 

26 (4). 


ssavage on LAPJG3WLY3PROD with BILLS
3 

•S 4389 IS

1 ‘‘(3) TREATMENT OF BLENDED RENEWABLE

2 NATURAL GAS.— 

3 ‘‘(A) IN GENERAL.—Under regulations 

4 prescribed by the Secretary, a sale of blended 

5 renewable natural gas shall be treated as a sale 

6 of renewable natural gas fuel if— 

7 ‘‘(i) at the time the renewable natural 

8 gas was blended with other compressed or 

9 liquefied natural gas, the taxpayer had a 

10 contract with the registered producer of 

11 such renewable natural gas for the sale of 

12 such gas for use as a fuel in a motor vehi13 cle or motorboat, or for use as a fuel in 

14 aviation, 

15 ‘‘(ii) such contract was entered into 

16 before the sale of the blended renewable 

17 natural gas and specifies the number of 

18 gallons of renewable natural gas provided 

19 for such purposes and the period for which 

20 such contract is in effect, and 

21 ‘‘(iii) the registered producer of such 

22 fuel provides to the taxpayer the certifi23 cation described in paragraph (4). 

24 ‘‘(B) LIMITATION.—The amount of blend25 ed renewable natural gas treated as renewable 


ssavage on LAPJG3WLY3PROD with BILLS
4 

•S 4389 IS

1 natural gas under subparagraph (A) for any pe2 riod shall not exceed the number of gallons of 

3 renewable natural gas specified under subpara4 graph (A)(ii) and certified by the producer 

5 under paragraph (4) for such period. 

6 ‘‘(C) BLENDED RENEWABLE NATURAL

7 GAS.—For purposes of this subsection, the term 

8 ‘blended renewable natural gas’ means com9 pressed or liquefied natural gas which consists 

10 of both renewable natural gas and other com11 pressed or liquefied natural gas. 

12 ‘‘(4) CERTIFICATION.—A certification is de13 scribed in this subparagraph if such certification— 

14 ‘‘(A) identifies the product produced and 

15 the gallon equivalent of fuel acquired by the 

16 taxpayer for a purpose described in paragraph 

17 (1), and 

18 ‘‘(B) is provided such form and manner as 

19 prescribed by the Secretary. 

20 ‘‘(5) GASOLINE GALLON EQUIVALENT.—For 

21 purposes of this subsection, the term ‘gasoline gallon 

22 equivalent’ means, with respect to any nonliquid re23 newable natural gas, the amount of such fuel having 

24 a Btu content of 124,800 (higher heating value). 


ssavage on LAPJG3WLY3PROD with BILLS
5 

•S 4389 IS

1 ‘‘(6) TERMINATION.—This subsection shall not 

2 apply to any sale or use for any period after Decem3 ber 31, 2033.’’. 

4 (b) APPLICATION OF OTHER RULES.— 

5 (1) REGISTRATION.—The last sentence of sec6 tion 6426(a) of the Internal Revenue Code of 1986 

7 is amended by striking ‘‘subsections (d) and (e)’’ 

8 and inserting ‘‘subsections (d), (e), and (l)’’. 

9 (2) DENIAL OF DOUBLE BENEFIT.—Section 

10 6426(h) of such Code is amended by striking ‘‘sub11 section (d) or (e)’’ and inserting ‘‘subsection (d), (e), 

12 or (l)’’. 

13 (3) FUEL MUST BE CONNECTED TO THE

14 UNITED STATES.—Section 6426(i) of such Code is 

15 amended by inserting after paragraph (2) the fol16 lowing new paragraph: 

17 ‘‘(3) RENEWABLE NATURAL GAS.—No credit 

18 shall be determined under this section with respect 

19 to any renewable natural gas which is produced out20 side the United States for use as a fuel outside the 

21 United States.’’. 

22 (4) ENERGY EQUIVALENCY.—Section 6426(j) of 

23 such Code is amended— 

24 (A) by inserting ‘‘or renewable natural 

25 gas,’’ after ‘‘alternative fuel’’, and 


ssavage on LAPJG3WLY3PROD with BILLS
6 

•S 4389 IS

1 (B) by inserting ‘‘or gas’’ after ‘‘such a 

2 fuel’’. 

3 (c) PAYMENTS.— 

4 (1) IN GENERAL.—Section 6427(e) of the Inter5 nal Revenue Code of 1986 is amended by redesig6 nating paragraphs (3) through (6) as paragraphs 

7 (4) through (7), respectively, and by inserting after 

8 paragraph (2) the following new paragraph: 

9 ‘‘(3) RENEWABLE NATURAL GAS.—If any per10 son sells or uses renewable natural gas (as defined 

11 in section 6426(k)(2)) for a purpose described in 

12 section 6426(k)(1) in such person’s trade or busi13 ness, the Secretary shall pay (without interest) to 

14 such person an amount equal to the renewable nat15 ural gas fuel credit with respect to such fuel.’’. 

16 (2) TERMINATION.—Section 6427(e)(7) of such 

17 Code, as redesignated by paragraph (1), is amended 

18 by striking ‘‘and’’ at the end of subparagraph (D), 

19 by striking the period at the end of subparagraph 

20 (E) and inserting ‘‘, and’’, and by adding at the end 

21 the following new subparagraph: 

22 ‘‘(F) any renewable natural gas (as defined 

23 in section 6426(k)(2)) sold or used after De24 cember 31, 2033.’’. 

25 (3) CONFORMING AMENDMENTS.— 


ssavage on LAPJG3WLY3PROD with BILLS
7 

•S 4389 IS

1 (A) Section 6427(e)(4) of such Code, as 

2 redesignated by paragraph (1), is amended— 

3 (i) by striking ‘‘paragraph (1) or (2)’’ 

4 and inserting ‘‘paragraph (1), (2), or (3)’’, 

5 and 

6 (ii) by striking ‘‘any mixture or alter7 native fuel’’ and inserting ‘‘any mixture, 

8 alternative fuel, or renewable natural gas’’. 

9 (B) Section 6427(e)(6) of such Code, as 

10 redesignated by paragraph (1), is amended by 

11 striking ‘‘alternative fuel credit or alternative 

12 fuel mixture credit’’ and inserting ‘‘alternative 

13 fuel credit, alternative fuel mixture credit, or 

14 renewable natural gas fuel credit’’. 

15 (C) Section 6427(e)(6) of such Code, as 

16 redesignated by paragraph (1), is amended— 

17 (i) by striking ‘‘paragraph (1) or (2)’’ 

18 and inserting ‘‘paragraph (1), (2), or (3)’’, 

19 and 

20 (ii) by striking ‘‘any mixture or alter21 native fuel’’ and inserting ‘‘any mixture, 

22 alternative fuel, or renewable natural gas’’. 

23 (d) REGISTRATION.—Section 4101(a) of such Code 

24 is amended— 


ssavage on LAPJG3WLY3PROD with BILLS
8 

•S 4389 IS

1 (1) by striking ‘‘and’’ before ‘‘every person pro2 ducing second generation biofuel’’, and 

3 (2) by inserting ‘‘, and every person producing 

4 renewable natural gas (as defined in section 

5 6426(k)(2))’’ after ‘‘(as defined in section 

6 40(b)(6)(E))’’. 

7 (e) EFFECTIVE DATE.—The amendments made by 

8 this section shall apply to fuel sold or used in calendar 

9 quarters beginning after the date of the enactment of this 

10 Act. 

Æ 


ssavage on LAPJG3WLY3PROD with BILLS