. (3) Section 1016(a) is amended— (A) in paragraph (37), by striking and at the end, (B) in paragraph (38), by striking the period at the end and inserting , and , and (C) by inserting at the end the following new paragraph: (39) to the extent provided in section 179D(f). . (4) Section 1245(a) is amended— (A) in paragraph (2)(C), by inserting 179F, after 179E, , and (B) in paragraph (3)(C), by inserting 179F, after 179E, . (5) The table of sections for part VI of subchapter B of chapter 1 is amended by inserting after the item relating to section 179E the following new item: Sec. 179F. Deduction for energy efficiency improvements to commercial buildings. . (c) Effective date The amendments made by this section shall apply to any energy efficiency improvements placed in service after December 31, 2020. 306. Temporary extension of existing energy efficiency incentives (a) Nonbusiness energy property (1) In general Paragraph (2) of section 25C(g) is amended by striking December 31, 2017 and inserting December 31, 2020 . (2) Effective date The amendments made by this subsection shall apply to property placed in service after December 31, 2017. (b) New energy efficient home credit (1) In general Subsection (g) of section 45L is amended by striking December 31, 2017 and inserting December 31, 2020 . (2) Effective date The amendments made by this subsection shall apply to any qualified new energy efficient home acquired after December 31, 2017. (c) Energy efficient commercial buildings deduction (1) In general Subsection (h) of section 179D is amended by striking December 31, 2017 and inserting December 31, 2020 . (2) Effective date The amendments made by this section shall apply to property placed in service after December 31, 2017. IV Clean Electricity and Fuel Bonds 401. Clean energy bonds (a) In general Part IV of subchapter A of chapter 1 is amended by inserting after subpart G the following new subpart: H Clean energy bonds Sec. 54. Clean energy bonds. 54. Clean energy bonds (a) In general If a taxpayer holds a