Zero-Emission Vehicle Legal and Regulatory Activities - Background

This page last reviewed October 14, 2011

The Zero Emission Vehicle (ZEV) regulation was first adopted in 1990 as part of the Low Emission Vehicle Program.  Although it has been modifed several times over the years, as shown in the timeline on page four, it still remains an important program for California’s air quality and has spurred many new technologies that are being driven on California’s roads.

While critics maintain that the ZEV regulation is a failure, in reality many successes have come out of the regulation.  For instance, nearly 2 million Californians are driving partial zero and advanced technology partial zero emission vehicles (PZEV and AT PZEV).  These vehicles have near-zero tailpipe emissions, zero evaporative emissions and an extended emissions warranty of 15 years or 150,000 miles.  In fact, they are 80% cleaner than the average 2002 model year car.

In addition to the variety of PZEVs and AT PZEVs available, gas-electric hybrid vehicles are also a success.  With more than 400,000 hybrids on California’s roads, they give consumers a way to reduce emissions and fuel consumption.  Although these “near- zero” emission vehicles provide critical pollution reductions in the near term, with the increases in California’s population and in the number of miles we travel each day, we must continue to pursue pure zero emission transportation technologies.

The Board’s motivation has always been to have zero emission technologies on the roads on a mass scale as soon as possible. Whether using fuel cells, battery electric vehicles, or other technologies, our commitment to zero emissions has never wavered. Our strategy, however, has appropriately considered the state of technology, market factors, economic impact, and our mission.

The Zero-Emission Vehicle Legal and Regulatory Activities page provides more information about the ZEV Regulatory activitiies over the years.

The ZEV Program Timeline:

1990 California embarked on a plan to reduce vehicle emissions to zero through the introduction of the Zero Emission Vehicle (ZEV) Program.  At that time, the Board required that in 1998, 2% of the vehicles that large manufacturers produced for sale in California had to be ZEVs, increasing to 5% in 2001 and 10% in 2003.
1996 The ZEV mandate was adjusted to eliminate the “ramp up” years but left in place the 10% ZEV requirement for 2003, and again in 1998 to allow partial ZEV (PZEV) credits for extremely clean vehicles that were not pure ZEVs.  The underlying goal, however, never changed.  California remained committed to seeing increasing numbers of ZEVs in the vehicle fleet.  The challenge was determining how to reach this goal.
2001 The challenge at this time was to maintain progress towards commercialization of ZEVs, while recognizing constraints due to cost, lead-time, and technical challenges.  The 2001 modifications allowed large manufacturers to meet their ZEV requirement with 2% pure ZEVs, 2% Advanced Technology PZEVS and 6% PZEVs.
2002 Due to a lawsuit filed against the Board, a federal district judge issued a preliminary injunction that prohibited the Board from enforcing the 2001 ZEV amendments with respect to the sale of new motor vehicles in model years 2003 or 2004.  Once the Board adopted the 2003 Amendments to the ZEV regulation, the parties to the lawsuits agreed to end the litigation.
2003 In order to address the preliminary injunction and better align the program requirements with the status of technology development, staff proposed additional modifications to the ZEV regulation in March 2003.  The reasons and benefits are described above.
2006 ARB held a Technology Symposium and an Independent Expert Review Panel submitted their report on the status of all ZEV technologies.
2007 Staff went to the Board in early 2007 with the information gathered from the Symposium as well as the report from the Independent Expert Review Panel.  The Board determined that staff should recommend changes to the regulation for the 2009 and subsequent model years.
2008 The Board approved modifications to the regulation at the March 27, 2008 hearing.  The Board also directed staff to redesign the ZEV Program so it will affect the 2015+ model years.
2009 The Board heard about staff's plans to redesign the ZEV program (2009 ZEV Review)
2010 Staff will present regulatory changes to the ZEV program