adding at the end the following new paragraph: (3) 30 percent of the amount paid or incurred by the taxpayer during the taxable year for home energy audits. . (2) Limitation Section 25C(b) is amended adding at the end the following new paragraph: (4) Home energy audits The amount of the credit allowed under this section by reason of subsection (a)(3) shall not exceed $150. . (3) Home energy audits Section 25C , as amended by subsections (a), is amended by redesignating subsections (e), (f), and (g), as subsections (f), (g), and (h), respectively, and by inserting after subsection (d) the following new subsection: (e) Home energy audits For purposes of this section, the term home energy audit means an inspection and written report with respect to a dwelling unit located in the United States and owned or used by the taxpayer as the taxpayer’s principal residence (within the meaning of section 121) which— (1) identifies the most significant and cost-effective energy efficiency improvements with respect to such dwelling unit, including an estimate of the energy and cost savings with respect to each such improvement, and (2) is conducted and prepared by a home energy auditor that meets the certification or other requirements specified by the Secretary (after consultation with the Secretary of Energy, and not later than 180 days after the date of the enactment of this subsection) in regulations or other guidance. . (4) Conforming amendment Section 1016(a)(33) is amended by striking section 25C(f) and inserting section 25C(g) . (l) Effective dates (1) Increase and modernization Except as otherwise provided by this subsection, the amendments made by this section shall apply to property placed in service after December 31, 2020. (2) Extension The amendments made by subsection (a) shall apply to property placed in service after December 31, 2020. (3) Home energy audits The amendments made by subsection (k) shall apply to amounts paid or incurred after December 31, 2020. 302. Residential energy efficient property (a)