; and (IV) for the period beginning on the day after the date of expiration of the period described in subclause (III) and ending on the date on which the total capacity of dispatchable low-emission technologies and dispatchable zero-emission technologies in the United States is greater than 20 gigawatts, as determined by the Secretary, 1.1. (C) Phase-out The quantity of Federal clean energy credits issued under this section to— (i) a generator described in subparagraph (A)(i) that is— (I) a qualified dispatchable low-emission technology shall be determined in accordance with subparagraph (A)(iii), effective beginning on the earlier of— (aa) the date on which the qualified dispatchable low-emission technology has been in service for 10 years; and (bb) January 1, 2035; and (II) a qualified dispatchable zero-emission technology shall be determined in accordance with subparagraph (A)(ii), effective beginning on the date on which the qualified dispatchable zero-emission technology has been in service for 10 years; (ii) a generator described in subparagraph (A)(ii) shall be determined in accordance with paragraphs (1) through (6), effective beginning on January 1, 2050; and (iii) a generator described in subparagraph (A)(iii) shall be determined in accordance with paragraphs (1) through (6), effective beginning on January 1, 2040. (D) Prohibition on double receipts A generator that receives Federal clean energy credits under subparagraph (A) may not receive any additional Federal clean energy credit under any of paragraphs (1) through (6). (g) Determination of carbon intensity and credit value (1) In general For purposes of determining the quantity of Federal clean energy credits under subsection (f), except as otherwise provided in this subsection, the Secretary shall determine the carbon intensity of each generator using data and methods from the Air Emission Measurement Center of the Environmental Protection Agency for emission testing and monitoring, including— (A) Continuous Emission Monitoring Systems