TO THE EDITOR:
Sept. 28 marked the 30th anniversary of California's zero-emission vehicle mandate. It originally required that by 2003, 10 percent of automakers' California sales be ZEVs, then foreseen to be battery-electric vehicles. Now, 30 years on, that 10 percent target is yet to be reached. The state aims to achieve in another 15 years a market shift of far greater magnitude than the original mandate ("California's fossil fuel ban likely in for long fight," Sept 28).
The ZEV mandate was relaxed repeatedly as the technology failed to become viable at the cost, capability and convenience needed for sufficient consumer adoption, even with large subsidies. The program was originally justified to clean up smog, but it turned out that greater progress could be made by cleaning up conventional vehicles than had been foreseen. For climate, however, there is no equivalent of the catalytic converter and reformulated gasoline, and so ZEVs do seem essential for the long run.
That being said, far more could be done today to improve gasoline vehicle efficiency, in particular, for leniently regulated pickups and SUVs. Indeed, in terms of the new fleet average carbon dioxide emissions, the past several years' shift to light trucks swamps at least four times over the potential CO2 reductions from ZEV sales to date.
Although California leadership is as crucial for climate as it has been for the success seen in conventional air quality, 30 years of experience with the ZEV program raises questions about today's policy priorities.
JOHN DeCICCO, Research professor emeritus, University of Michigan Energy Institute, Ann Arbor, Mich.