; and (2) in 2040, the aggregate quantity of greenhouse gas emissions from covered entities does not exceed zero. (b) Definition For purposes of this section, the term greenhouse gas emissions from covered entities in 2019 means greenhouse gas emissions to which section 721 would have applied if the requirements of this title for the specified year had been in effect for 2019. B Designation of Greenhouse Gases and Thermal Energy Reporting Program 711. Greenhouse gases For purposes of this title, the following are greenhouse gases: (1) Carbon dioxide. (2) Methane. (3) Nitrous oxide. (4) Sulfur hexafluoride. (5) Any perfluorocarbon. (6) Nitrogen trifluoride. 712. Carbon dioxide equivalent value of greenhouse gases (a) In general Any provision of this title that refers to a quantity or percentage of a quantity of a greenhouse gas shall be treated as a reference to the quantity or percentage of the greenhouse gas expressed in carbon dioxide equivalents. (b) Values Except as provided by the Administrator under subsection (c), for the purposes of this title, the carbon dioxide equivalent value of a greenhouse gas shall be equal to the 100-year global warming potential for such greenhouse gas that is provided in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. (c) Use of 20-Year global warming potential If the Administrator determines that it is more appropriate for a greenhouse gas, the Administrator may publish a determination in the Federal Register that such greenhouse gas has a carbon dioxide equivalent value equal to the 20-year global warming potential for such greenhouse gas that is provided in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. 713. Thermal energy reporting program (a) Regulations Not later than 18 months after the date of enactment of this title, the Administrator shall issue regulations establishing a program, to be known as the Federal thermal energy reporting program. Such regulations shall— (1) require each thermal reporting entity to