49 U.S.C. § 32902 — Average fuel economy standards

(a) Prescription of standards by regulation. At least 18 months before each model year starts, the Secretary of Transportation must set, by regulation, average fuel economy standards for the automobiles each manufacturer builds that year. Each standard must be the highest average fuel economy the Secretary decides manufacturers can realistically reach that year.

(b) Standards for automobiles and certain other vehicles. (1) After consulting the Secretary of Energy and the EPA Administrator, the Secretary must set separate average fuel economy standards for (A) passenger automobiles, starting with model year 2011; (B) non-passenger automobiles, also starting with model year 2011; and (C) work trucks and commercial medium- and heavy-duty on-highway vehicles, under the rules in subsection (k). (2)(A) For model years 2011 through 2020, the Secretary must set standards designed so that, by model year 2020, the combined passenger-and-non-passenger fleet sold in the U.S. averages at least 35 miles per gallon. (B) For model years 2021 through 2030, each fleet's required average is simply whatever the Secretary decides is the maximum feasible average fuel economy for that year. (C) In setting the standards under (A), the Secretary must make the required average climb steadily, year by year, from model year 2011 to model year 2020. (3) The Secretary must (A) write separate standards for passenger and non-passenger automobiles, based on one or more vehicle features connected to fuel economy, and express each standard as a mathematical formula; and (B) issue standards that cover at least 1 model year and no more than 5 model years at a time. (4) On top of any standard set under paragraph (3), every manufacturer must also meet a minimum standard for the passenger automobiles it builds domestically. That minimum is whichever is higher: (A) 27.5 miles per gallon, or (B) 92 percent of the average fuel economy the Secretary projects for the combined domestic and imported passenger-automobile fleet sold in the U.S. that year by all manufacturers — a projection the Secretary must publish in the Federal Register when announcing that year's standard.

(c) Amending passenger automobile standards. The Secretary may amend the standard under subsection (b) for a given model year to whatever level is the maximum feasible average fuel economy for that year. The normal rulemaking process in section 553 of title 5 applies, but any interested person may also make an oral presentation, and a transcript of it must be kept.

(d) Exemptions. (1) Except as paragraph (3) allows, a manufacturer that made fewer than 10,000 passenger automobiles worldwide in the model year 2 years before the one it's applying for may ask the Secretary for an exemption from the standard in subsection (b) or (c). The exemption for a given year only applies if the manufacturer actually makes fewer than 10,000 passenger automobiles worldwide that year. The Secretary may grant the exemption only after (A) finding that the regular standard is stricter than the maximum this manufacturer can feasibly achieve, and (B) setting, by regulation, an alternative standard that the Secretary decides is the maximum this manufacturer can feasibly achieve. (2) This alternative standard can apply to one exempted manufacturer alone, to every automobile this subsection covers, or to specific classes of passenger automobiles the Secretary defines by regulation, as long as they're made by exempted manufacturers. (3) Despite paragraph (1), an importer registered under section 30141(c) cannot get this manufacturer exemption for a vehicle it imports, or brings into compliance with safety standards for an individual under section 30142. (4) The Secretary may set what information an exemption application must include.

(e) Emergency vehicles. (1) In this subsection, an "emergency vehicle" is an automobile built mainly to serve (A) as an ambulance or combination ambulance-hearse, (B) as a law-enforcement vehicle for a federal, state, or local government, or (C) for other emergency uses the Secretary lists by regulation. (2) A manufacturer may choose to leave an emergency vehicle's fuel economy out of the calculation used for the standards in subsections (a) through (d). It makes this choice by notifying the Secretary and the EPA Administrator in writing.

(f) Considerations on decisions on maximum feasible average fuel economy. In deciding what's maximum feasible under this section, the Secretary must weigh technological feasibility, economic practicality, how other federal motor vehicle standards affect fuel economy, and the country's need to conserve energy.

(g) Requirements for other amendments. (1) The Secretary may amend a standard set under subsection (a) or (d), as long as the amended standard still meets that subsection's requirements. (2) If an amendment makes a standard stricter, the Secretary must issue it — and send it to Congress, when subsection (c)(2) requires that — at least 18 months before the model year it applies to begins.

(h) Limitations. In carrying out subsections (c), (f), and (g), the Secretary (1) may not count a dedicated automobile's fuel economy; (2) must treat a dual fueled automobile as though it only ran on gasoline or diesel; and (3) may not consider, when setting a standard, whether credits under section 32903 are being traded, transferred, or available.

(i) Consultation. The Secretary must consult the Secretary of Energy in carrying out this section and section 32903.

(j) Secretary of Energy comments. (1) Before proposing or amending a standard under subsection (a), (c), or (g), the Secretary of Transportation must give the Secretary of Energy at least 10 days from receiving the proposal to comment in writing, if the Secretary of Energy believes the proposal would hurt energy-conservation goals. If the Secretary of Transportation doesn't revise the proposal to address those comments, the comments must be included in the public notice. (2) Before taking final action on a standard or an exemption, the Secretary of Transportation must notify the Secretary of Energy and give a reasonable time to comment.

(k) Commercial medium- and heavy-duty on-highway vehicles and work trucks. (1) Study. Within 1 year after the National Academy of Sciences publishes its study required by section 108 of the Ten-in-Ten Fuel Economy Act, the Secretary — consulting the Secretary of Energy and the EPA Administrator — must study the fuel efficiency of commercial medium- and heavy-duty on-highway vehicles and work trucks, and decide (A) the right test methods for measuring their fuel efficiency; (B) the right way to measure and express that efficiency, considering things like the work these vehicles do and how they're used; (C) the range of factors — like design, function, use, duty cycle, infrastructure, and overall energy use and operating cost — that affect their fuel efficiency; and (D) any other factors or conditions that could affect a program to improve it. (2) Rulemaking. Within 24 months after finishing that study, the Secretary — again consulting the Secretary of Energy and the EPA Administrator — must decide, through a rulemaking, how to run a fuel-efficiency improvement program for these vehicles aimed at the maximum feasible improvement, and must adopt test methods, measurement metrics, fuel economy standards, and enforcement rules that are practical, cost-effective, and technologically doable. The Secretary may set different standards for different vehicle classes. (3) Lead-time; regulatory stability. Any standard the Secretary adopts under this subsection must give manufacturers at least (A) 4 full model years of lead time before it takes effect, and (B) 3 full model years where it stays unchanged.