1. Short title This Act may be cited as the Renewable Natural Gas Incentive Act of 2023 . 2. Increased credit for renewable natural gas (a) In general Section 6426 of the Internal Revenue Code of 1986 is amended— (1) in subsection (a)(2), by inserting and (l) after subsection (d) , and (2) by adding at the end the following new subsection: (l) Renewable natural gas fuel credit (1) In general For purposes of this section, the renewable natural gas fuel credit is the product of $1.00 and the number of gallons of renewable natural gas or gasoline gallon equivalents of a nonliquid renewable natural gas sold by the taxpayer for use as a fuel in a motor vehicle or motorboat, sold by the taxpayer for use as a fuel in aviation, or so used by the taxpayer. (2) Renewable natural gas For purposes of this section, the term renewable natural gas means compressed or liquefied gas derived from biomass (as defined in section 45K(c)(3))— (A) which produced by a person registered under section 4101(a), and (B) with respect to which the producer has made a certification described in paragraph (4). (3) Treatment of blended renewable natural gas (A) In general Under regulations prescribed by the Secretary, a sale of blended renewable natural gas shall be treated as a sale of renewable natural gas fuel if— (i) at the time the renewable natural gas was blended with other compressed or liquefied natural gas, the taxpayer had a contract with the registered producer of such renewable natural gas for the sale of such gas for use as a fuel in a motor vehicle or motorboat, or for use as a fuel in aviation, (ii) such contract was entered into before the sale of the blended renewable natural gas and specifies the number of gallons of renewable natural gas provided for such purposes and the period for which such contract is in effect, and (iii) the registered producer of such fuel provides to the taxpayer the certification described in paragraph (4). (B) Limitation The amount of blended renewable natural gas treated as renewable natural gas