1. Short title This Act may be cited as the Biodiesel, Renewable Diesel, and Alternative Fuels Extension Act of 2017 . 2. Extension of biodiesel and renewable diesel incentives (a) Income tax credit (1) Extension Subsection (g) of section 40A of the Internal Revenue Code of 1986 is amended by striking December 31, 2016 and inserting December 31, 2021 . (2) Phasedown Subsection (b) of section 40A of such Code is amended by adding at the end the following: (5) Phasedown In the case of taxable years beginning after 2018, paragraphs (1)(A) and (2)(A) shall each be applied by substituting for $1.00 the following: (A) $0.75 for taxable years beginning in 2019, and (B) $0.50 for taxable years beginning after 2019. . (b) Excise tax incentives (1) Credit Paragraph (6) of section 6426(c) of such Code is amended by striking December 31, 2016 and inserting December 31, 2021 . (2) Payments Subparagraph (B) of section 6427(e)(6) of such Code is amended by striking December 31, 2016 and inserting December 31, 2021 . (3) Phasedown Paragraph (2) of section 6426(c) of such Code is amended by inserting before the period at the end the following: ($0.75 for fuel sold or used in 2019 and $0.50 for fuel sold or used after 2019) . (c) Effective date The amendments made by this section shall apply to fuel sold or used after December 31, 2016. 3. Extension of excise tax credits relating to alternative fuels (a) Extension of alternative fuels excise tax credits (1) In general Paragraph (5) of section 6426(d) and paragraph (3) of section 6426(e) of the Internal Revenue Code of 1986 are each amended by striking December 31, 2016 and inserting December 31, 2021 . (2) Outlay payments for alternative fuels Subparagraph (C) of section 6427(e)(6) of such Code is amended by striking December 31, 2016 and inserting December 31, 2021 . (3) Phasedown (A) Alternative fuel credit Paragraph (1) of section 6426(d) of such Code is amended by inserting (37.5 cents for fuel sold or used in 2019 and 25 cents for fuel sold or used after 2019) after 50 cents