; or (2) for a retail electric supplier that does not exceed the maximum allowable percentage of fossil fuel energy generation for the applicable calendar year, as determined under subsection (c), a certification of that compliance, as the Administrator determines to be appropriate. (c) Maximum allowable annual percentage of fossil fuel energy sales For calendar years 2022 through 2050, in annual increments, the maximum annual percentage of the base quantity of electricity of a retail electric supplier that may be generated from fossil fuel resources, or otherwise credited towards the percentage requirement pursuant to subsection (e), shall be the applicable percentage specified in the following table: Maximum Allowable Annual Percentage of Fossil Fuel Energy Sales Calendar Year Percentage 2022 70.0 2023 67.5 2024 65.0 2025 62.5 2026 60.0 2027 57.5 2028 55.0 2029 52.5 2030 50.0 2031 47.5 2032 45.0 2033 42.5 2034 40.0 2035 37.5 2036 35.0 2037 32.5 2038 30.0 2039 27.5 2040 25.0 2041 22.5 2042 20.0 2043 17.5 2044 15.0 2045 12.5 2046 10.0 2047 7.5 2048 5.0 2049 2.5 2050 0.0. (d) Requirement for 2050 and thereafter For calendar year 2050 and each calendar year thereafter, a retail electric supplier shall not generate or sell any fossil fuel energy. (e) Fossil fuel energy credits (1) In general A retail electric supplier may satisfy the requirements of subsection (b) through the submission of fossil fuel energy credits— (A) issued to the retail electric supplier under subsection (f); or (B) obtained by purchase, transfer, or exchange under subsection (g), subject to any emissions adjustment under subsection (f)(3)(B). (2) Limitation A fossil fuel energy credit may be counted toward compliance with subsection (b) only once. (f) Issuance of fossil fuel energy credits (1) In general Not later than 1 year after the date of enactment of this section, the Administrator shall establish by rule a program— (A) to verify and issue fossil fuel energy credits to retail electric suppliers