The federal programs now in place appear to have a substantial potential to address the several problem areas that have prevented satisfactory control of vehicle emissions. The combination of reformulated gasoline and I&M targeting of evaporative emissions should greatly improve control of these emissions in noncomplying regions.
Improved l&M programs, coupled with more stringent standards, onboard diagnostics, and increased emission control warranties for new vehicles, should reduce the number of “super emitters” among relatively new vehicles. Some past problems with misfueling catalyst-equipped vehicles with leaded fuel (which poisons the catalyst) will cease because leaded fuel is no longer available in the general market.
Further, today’s vehicles, with their sophisticated computer controls, are far less vulnerable to tampering problems. In addition, increased use of alternative fuels, especially natural gas and electricity, should have some positive effect. The California emission programs, which may be adopted by some northeastern states, create the potential for sharp drops in the certified emission levels of the new car fleet.
Reasons for accomplish
There has been substantial controversy about the most extreme of these measures, the ZEV and ultralow emission vehicle (ULEV) standards. Auto manufacturers have argued that attainment of ULEV standards will be extremely expensive ($1,000 or more for each vehicle), and that battery technology is not yet sufficiently advanced to allow enough vehicle range and battery longevity to satisfy consumers.
Recent developments appear to have improved the prospects for attainment of ULEV levels at substantially lower cost for at least some classes of vehicles–the 1994 Toyota Camry came very close to ULEV certification levels, and Honda has recently announced attainment of these levels with a modified Accord, at a few hundred dollars per vehicle.
6 The potential for EVs is discussed in some detail in this report. There are potential limitations to the effectiveness of some of the emission control programs. For example, some studies have shown that a significant percentage of vehicles that underwent repairs after failing l&M tests were inadequately repaired. Furthermore, EPA has recently backed off the l&M dynamometer requirements and central testing for states now using decentralized testing, and the survival of these requirements is in doubt.
This may compromise the ability of the l&M program to ensure the identification and repair of noncomplying vehicles. And, although fuels such as natural gas and electricity will yield substantial “per vehicle” emissions reductions, it is far from clear whether the existing programs will result in widespread availability of these fuels.