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The Advanced Clean Cars Program

This page last reviewed September 1, 2017

Continuing its leadership role in developing innovative and ground breaking emission control programs, the California Air Resources Board (CARB) adopted the Advanced Clean Cars (ACC) program in 2012. This historic program, developed in coordination with the United States (U.S.) Environmental Protection Agency (EPA) and National Highway Traffic Safety Administration (NHTSA), combined the control of smog-causing (criteria) pollutants and greenhouse gas (GHG) emissions into a single coordinated set of requirements for model years 2015 through 2025. ACC assured the development of environmentally superior passenger cars and other vehicles that will continue to deliver the performance, utility, and safety vehicle owners have come to expect, all while saving the consumer money through significant fuel savings. 



ACC is an integral part of California’s ambitious long-term requirements to reduce the State’s impact on climate change and improve ambient air quality.  The components of the ACC program are the Low-Emission Vehicle (LEV) regulations that reduce criteria pollutants and GHG emissions from light- and medium-duty vehicles, and the Zero-Emission Vehicle (ZEV) regulation, which requires manufacturers to produce an increasing number of pure ZEVs (meaning battery electric and fuel cell electric vehicles), with provisions to also produce plug-in hybrid electric vehicles (PHEV) in the 2018 through 2025 model years. 

The vehicle programs are a critical component in the State Implementation Plan (SIP) for achieving national ambient air quality standards in the South Coast and San Joaquin Valley.  They are also integral in ARB’s Scoping Plan to achieve the GHG reduction goals that were established through California legislation and Executive Orders.


Developing the Next Phase of Regulations
Following the completion of the ACC midterm review in March 2017, the Board affirmed that the current regulations remain approprate and further directed staff to develop proposals for future consideration to strengthen the program for future model years. To begin the public process for developing the next generation of the ACC program, staff has released a concept solicitation intended to elicit feedback from stakeholders on future regulatory changes.

  • Concept Solicitation for Advanced Clean Cars Regulations for Future New Light-Duty Vehicles
  • Submit public comments by Monday, October 16, 2017 at 5 pm

Based on public feedback, a subsequent discussion document will be released in advance of a public workshop to gather further input. Timing for the discussion paper and workshop will be dependent on the range of concepts and input received but would likely begin by late 2017.


Midterm Review

When the ARB adopted the ACC program in 2012, the agency committed to conduct a comprehensive Midterm Review (MTR) of three elements of the program -- the ZEV regulation, the 1 milligram per mile (mg/mi) particulate matter (PM) standard, and the light-duty vehicle greenhouse gas standards for 2022 and later model years. ARB's Resolution 12-11 specified areas for staff to consider for its review and staff presented annual informational items to the board, with the final report released in December 2016. 

A Midterm Evaluation (MTE) of the light-duty vehicle greenhouse gas standards for 2022 and later model years is also being conducted at the national level, and ARB staff are collaborating with the U.S. EPA and the NHTSA to review the standards since the California program closely mirrors the national program for these model years.

On November 30, 2016, EPA released a Proposed Determination finding that the MY 2022-2025 GHG standards remain appropriate and that a rulemaking to change them is not warranted. This determination was based on the robust technical record including the joint-agency 2016 draft Technical Assessment Report (TAR), input from the auto industry and other stakeholders, and updated analyses. Subsequent to a review of public comment, U.S. EPA concluded their midterm evaluation and published a Final Determination in January 2017 that affirmed the existing federal greenhouse gas standards would remain as adopted.

ARB released its Advanced Clean Cars Midterm Review Report on January 18, 2017. This report and its appendices encompass ARB's technical analysis for the midterm review of the adopted LEV III GHG and PM emission standards and ZEV requirements. The report includes recommendations to the Board for next steps for each of the adopted requirements.


Research & Assessment

Success of the ACC program requires regular assessment of the state of technology, industry parameters, and the consumer market in order to ensure maximum feasible benefits. ARB has sponsored or co-sponsored extramural research projects to support the mid-term review:


Research Contract




Technical Analysis of Vehicle Load-Reduction Potential for Advanced Clean Cars


Gregory Pannone, Control Tec
(now Novation Analytics)


New Car Buyer’s Valuation of Zero-Emission Vehicles


Kenneth Kurani,
University of California, Davis


Very Low PM Measurements forLlight-Duty Vehicles (E-99)


Heejung Jung,
University of California, Riverside


The Dynamics of Plug-in Electric Vehicles in the Secondary Market and Their Implications for Vehicle Demand, Durability, and Emissions


Gil Tal,
University of California, Davis


Examining Factors that Influence ZEV Sales in California


JR DeShazo
University of California, Los Angeles


Advanced Plug-In Electric Vehicle Usage and Charging Behavior


Tom Turrentine,
University of California, Davis


In September 2016 staff held an Advanced Clean Cars Symposium, “The Road Ahead”  that brought together automakers, suppliers, and other clean car stakeholders to look at technologies that expand upon the TAR, and help inform the ARB midterm review. The first day featured presentations made by representatives from industry and academia on various groundbreaking trends in ZEV technologies, including the latest in battery technology, wireless charging, and ARB’s analysis of manufacturer provided plug-in electric vehicles (PEV) in-use data and emissions testing of PHEVs.  The second day covered engine and vehicle technologies that were not extensively used in the analysis for the joint agency 2016 TAR but are expected to be on production vehicles in the near term and could help meet the adopted GHG and PM standards.


Market Support & ZEV Collaboration

Implementation of the ACC program requires a variety of government actions beyond regulatory development in order to encourage ZEV sales and usage, remove market barriers and establish necessary charging/refueling infrastructure. As outlined in California’s ZEV Action Plan state agencies and legislation play an important role in promoting growth in the ZEV market, such as through incentives like the Clean Vehicle Rebate Project or single-occupant access to carpool lanes as well as investments in hydrogen fueling stations and fast-charging stations. Collaborating with state, national and international partners is a key program strategy as well that helps address challenges to ZEV market expansion in California and beyond, including technology development and cost reduction.



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PEV resource center




Additional Program Information


bullet ZEV Program

bullet LEV III Program

bullet Midterm Review and TAR

bullet ACC Symposium: The Road Ahead (September 2016)

bullet ZEV Collaboration

bullet ACC Program Fact Sheet in English and Spanish

bullet Summary of the ACC Program

Early Program Activity


bullet News Release: California Air Resources Board Releases Proposed Advanced Clean Car Rules (December 2011)

bullet News Release: California Air Resources Board Approves Advanced Clean Car Rules (January 2012)

bullet News Release: ARB proposes regulations to accept Federal GHG vehicle standards (August 2012)

bullet Presentation from Community Meetings (July 2011)

bullet Proposed ACC Amendments: AB1085 Background Materials for Emissions Data, Economic Data and Public Health Impacts