California has made significant progress in improving air quality in many parts of the state. However, substantial reductions in emissions of non-methane organic gases (NMOG) and oxides of nitrogen (NOx) are still needed to meet federal standards in California's South Coast Air Basin by 2010, as required by the Clean Air Act.1 The South Coast Air Quality Management District (SCAQMD) and the California Air Resources Board (CARB) have adopted an aggressive strategy to reduce emissions. A controversial part of this strategy is the state's Zero Emission Vehicle (ZEV) program, which requires that auto manufacturers begin selling ZEVs starting in 2003. The ZEV program is a first step in achieving CARB's long-term goal of reducing emissions from California's motor vehicle fleet to zero. CARB believes that reliance on traditional gasoline-engine technology will not allow California to meet federal air quality standards.
This report examines whether ZEVs are a cost-effective way to achieve air quality standards in California. To this end, it examines the promise of technologies that could be used to satisfy ZEV program requirements. It examines the costs of ZEVs, the emission benefits that ZEVs generate, and the cost per ton of emissions reduced through the use of ZEVs. It reviews the ZEV program in the context of the state's overall strategy for reducing emissions in the South Coast Air Basin and compares the cost-effectiveness of ZEVs (as measured by cost per ton of emissions reduced) with that of other components of the overall strategy. It concludes with recommendations for policies on ZEVs and on California's strategy for controlling emissions from passenger cars and light-duty trucks more generally.
To achieve federal ozone standards in the South Coast Air Basin, the SCAQMD estimates that NMOG and NOx emissions cannot exceed 413 and 530 tons per day, respectively. These levels are roughly one-half the emission rates observed in recent years. Regulations expected to achieve more than the required emission reductions for NOx have been adopted, but such is not the case for NMOG. Programs that reduce NMOG emissions by another 138 tons per day must still be found.2____________________