((a)) ** .—** At least 18 months before the beginning of each model year, the Secretary of Transportation shall prescribe by regulation average fuel economy standards for automobiles manufactured by a manufacturer in that model year. Each standard shall be the maximum feasible average fuel economy level that the Secretary decides the manufacturers can achieve in that model year.

((b))

((1)) ** .—** The Secretary of Transportation, after consultation with the Secretary of Energy and the Administrator of the Environmental Protection Agency, shall prescribe separate average fuel economy standards for—

((A)) passenger automobiles manufactured by manufacturers in each model year beginning with model year 2011 in accordance with this subsection;

((B)) non-passenger automobiles manufactured by manufacturers in each model year beginning with model year 2011 in accordance with this subsection; and

((C)) work trucks and commercial medium-duty or heavy-duty on-highway vehicles in accordance with subsection (k).

((2))

((A)) ** .—** The Secretary shall prescribe a separate average fuel economy standard for passenger automobiles and a separate average fuel economy standard for non-passenger automobiles for each model year beginning with model year 2011 to achieve a combined fuel economy average for model year 2020 of at least 35 miles per gallon for the total fleet of passenger and non-passenger automobiles manufactured for sale in the United States for that model year.

((B)) ** .—** For model years 2021 through 2030, the average fuel economy required to be attained by each fleet of passenger and non-passenger automobiles manufactured for sale in the United States shall be the maximum feasible average fuel economy standard for each fleet for that model year.

((C)) ** .—** In prescribing average fuel economy standards under subparagraph (A), the Secretary shall prescribe annual fuel economy standard increases that increase the applicable average fuel economy standard ratably beginning with model year 2011 and ending with model year 2020.

((3)) ** .—** The Secretary shall—

((A)) prescribe by regulation separate average fuel economy standards for passenger and non-passenger automobiles based on 1 or more vehicle attributes related to fuel economy and express each standard in the form of a mathematical function; and

((B)) issue regulations under this title prescribing average fuel economy standards for at least 1, but not more than 5, model years.

((4)) ** .—** In addition to any standard prescribed pursuant to paragraph (3), each manufacturer shall also meet the minimum standard for domestically manufactured passenger automobiles, which shall be the greater of—

((A)) 27.5 miles per gallon; or

((B)) 92 percent of the average fuel economy projected by the Secretary for the combined domestic and non-domestic passenger automobile fleets manufactured for sale in the United States by all manufacturers in the model year, which projection shall be published in the Federal Register when the standard for that model year is promulgated in accordance with this section.

((c)) ** .—** The Secretary of Transportation may prescribe regulations amending the standard under subsection (b) of this section for a model year to a level that the Secretary decides is the maximum feasible average fuel economy level for that model year. applies to a proceeding to amend the standard. However, any interested person may make an oral presentation and a transcript shall be taken of that presentation.

((d)) ** .—**

((1)) Except as provided in paragraph (3) of this subsection, on application of a manufacturer that manufactured (whether in the United States or not) fewer than 10,000 passenger automobiles in the model year 2 years before the model year for which the application is made, the Secretary of Transportation may exempt by regulation the manufacturer from a standard under subsection (b) or (c) of this section. An exemption for a model year applies only if the manufacturer manufactures (whether in the United States or not) fewer than 10,000 passenger automobiles in the model year. The Secretary may exempt a manufacturer only if the Secretary—

((A)) finds that the applicable standard under those subsections is more stringent than the maximum feasible average fuel economy level that the manufacturer can achieve; and

((B)) prescribes by regulation an alternative average fuel economy standard for the passenger automobiles manufactured by the exempted manufacturer that the Secretary decides is the maximum feasible average fuel economy level for the manufacturers to which the alternative standard applies.

((2)) An alternative average fuel economy standard the Secretary of Transportation prescribes under paragraph (1)(B) of this subsection may apply to an individually exempted manufacturer, to all automobiles to which this subsection applies, or to classes of passenger automobiles, as defined under regulations of the Secretary, manufactured by exempted manufacturers.

((3)) Notwithstanding paragraph (1) of this subsection, an importer registered under may not be exempted as a manufacturer under paragraph (1) for a motor vehicle that the importer—

((A)) imports; or

((B)) brings into compliance with applicable motor vehicle safety standards prescribed under chapter 301 of this title for an individual under .

((4)) The Secretary of Transportation may prescribe the contents of an application for an exemption.

((e)) ** .—**

((1)) In this subsection, “emergency vehicle” means an automobile manufactured primarily for use—

((A)) as an ambulance or combination ambulance-hearse;

((B)) by the United States Government or a State or local government for law enforcement; or

((C)) for other emergency uses prescribed by regulation by the Secretary of Transportation.

((2)) A manufacturer may elect to have the fuel economy of an emergency vehicle excluded in applying a fuel economy standard under subsection (a), (b), (c), or (d) of this section. The election is made by providing written notice to the Secretary of Transportation and to the Administrator of the Environmental Protection Agency.

((f)) ** .—** When deciding maximum feasible average fuel economy under this section, the Secretary of Transportation shall consider technological feasibility, economic practicability, the effect of other motor vehicle standards of the Government on fuel economy, and the need of the United States to conserve energy.

((g)) ** .—**

((1)) The Secretary of Transportation may prescribe regulations amending an average fuel economy standard prescribed under subsection (a) or (d) of this section if the amended standard meets the requirements of subsection (a) or (d), as appropriate.

((2)) When the Secretary of Transportation prescribes an amendment under this section that makes an average fuel economy standard more stringent, the Secretary shall prescribe the amendment (and submit the amendment to Congress when required under subsection (c)(2) of this section) at least 18 months before the beginning of the model year to which the amendment applies.

((h)) ** .—** In carrying out subsections (c), (f), and (g) of this section, the Secretary of Transportation—

((1)) may not consider the fuel economy of dedicated automobiles;

((2)) shall consider dual fueled automobiles to be operated only on gasoline or diesel fuel; and

((3)) may not consider, when prescribing a fuel economy standard, the trading, transferring, or availability of credits under section 32903.

((i)) ** .—** The Secretary of Transportation shall consult with the Secretary of Energy in carrying out this section and .

((j)) ** .—**

((1)) Before issuing a notice proposing to prescribe or amend an average fuel economy standard under subsection (a), (c), or (g) of this section, the Secretary of Transportation shall give the Secretary of Energy at least 10 days from the receipt of the notice during which the Secretary of Energy may, if the Secretary of Energy concludes that the proposed standard would adversely affect the conservation goals of the Secretary of Energy, provide written comments to the Secretary of Transportation about the impact of the standard on those goals. To the extent the Secretary of Transportation does not revise a proposed standard to take into account comments of the Secretary of Energy on any adverse impact of the standard, the Secretary of Transportation shall include those comments in the notice.

((2)) Before taking final action on a standard or an exemption from a standard under this section, the Secretary of Transportation shall notify the Secretary of Energy and provide the Secretary of Energy a reasonable time to comment.

((k))

((1)) ** .—** Not later than 1 year after the National Academy of Sciences publishes the results of its study under section 108 of the Ten-in-Ten Fuel Economy Act, the Secretary of Transportation, in consultation with the Secretary of Energy and the Administrator of the Environmental Protection Agency, shall examine the fuel efficiency of commercial medium- and heavy-duty on-highway vehicles and work trucks and determine—

((A)) the appropriate test procedures and methodologies for measuring the fuel efficiency of such vehicles and work trucks;

((B)) the appropriate metric for measuring and expressing commercial medium- and heavy-duty on-highway vehicle and work truck fuel efficiency performance, taking into consideration, among other things, the work performed by such on-highway vehicles and work trucks and types of operations in which they are used;

((C)) the range of factors, including, without limitation, design, functionality, use, duty cycle, infrastructure, and total overall energy consumption and operating costs that affect commercial medium- and heavy-duty on-highway vehicle and work truck fuel efficiency; and

((D)) such other factors and conditions that could have an impact on a program to improve commercial medium- and heavy-duty on-highway vehicle and work truck fuel efficiency.

((2)) ** .—** Not later than 24 months after completion of the study required under paragraph (1), the Secretary, in consultation with the Secretary of Energy and the Administrator of the Environmental Protection Agency, by regulation, shall determine in a rulemaking proceeding how to implement a commercial medium- and heavy-duty on-highway vehicle and work truck fuel efficiency improvement program designed to achieve the maximum feasible improvement, and shall adopt and implement appropriate test methods, measurement metrics, fuel economy standards, and compliance and enforcement protocols that are appropriate, cost-effective, and technologically feasible for commercial medium- and heavy-duty on-highway vehicles and work trucks. The Secretary may prescribe separate standards for different classes of vehicles under this subsection.

((3)) ** .—** The commercial medium- and heavy-duty on-highway vehicle and work truck fuel economy standard adopted pursuant to this subsection shall provide not less than—

((A)) 4 full model years of regulatory lead-time; and

((B)) 3 full model years of regulatory stability.