A Cost-Effectiveness Study of Carbon Monoxide Emissions Reduction Utilizing Remote Sensing

Abstract

The cost-effectiveness of identification and repair of vehicles with excessive carbon monoxide emissions was investigated over the 1991-92 winter period in Provo, Utah. This pilot program used on-road remote sensing at two locations to identify repeat gross polluting vehicles. The owners of gross polluters observed at one of the locations were solicited for a free repair program carried out under the direction of the Utah Valley Community College, Auto-Diesel Division. The same two locations were revisited after the repair program had terminated and the vehicle emissions were remeasured. More than 17,000 measurements of over 10,000 individual vehicles were obtained. As observed elsewhere, half of the total carbon monoxide was emitted by only about ten percent of the vehicles. Solicitation letters were sent to 114 owners and 47 vehicles were recruited and repairs attempted. Df the 47 vehicles, 28 were remeasured when the site was revisited at the end of the program. They had improved their measured on-road emissions by more than 50 percent. The vehicles which were identified as gross polluters at the second location-but were not notified of their status-were used as a control group. Their emissions were also reduced, as expected, but only by 14 percent. This pilot program demonstrates carbon monoxide emissions reduction at a cost effectiveness of $200 per ton, not including the cost benefits of gas mileage improvement. Two hundred dollars per ton is lowerthan many current or proposed mandated programs. The owner's repair cost would more than pay for itself in terms of improved fuel economy. The program would also generate the on-road fleet emissions data necessary to evaluate its effectiveness. Without such data, a program is forced to rely upon computer modeling with its known limitations. Most vehicles show CO/CO 2 and HC/ CO 2 ratios close to zero. When CO/CO 2 ratios greater than zero are observed, the engine must be operating with a fuel rich air/fuel ratio. In the case of a large HC/ CO 2 ratio, a fuel lean air/fuel ratio which is

Enhancement of Remote Sensing for Mobile Source Nitric Oxide

“…5 - 6 The remote sensing technique has also been applied successfully to measure vehicle emissions in a tunnel environment.…”

Characterizing the effects of driver variability on real-world vehicle emissions

“…hard accelerations, heavy loads on steep hills) for well-tuned vehicles, but may occur transiently for malfunctioning vehicles (Black, 1991;Ross, 1994;Ross et al, 1995). A malfunction of either a feedback component or the catalyst causes extremely high emissions that are driver-independent and beyond the scope of this study, but malfunctions have been shown to be an important component in realworld vehicles (Lawson et al, 1990;Bishop et al, 1993;Calvert et al, 1993;Hickman, 1994;Stephens, 1994;Beaton et al, 1995;Bishop et al, 1996;McLaren et al, 1996;Stedman, 1996;Zhang et al, 1996).…”

“…Nevertheless, the availability of this data has led to widespread use of these laboratory results to predict real-world pollutant levels using emission factor models such as EMFAC (California Air Resources Board) and MOBILE (U.S. EPA). Recent ®eld studies of actual emissions via tunnel studies (Pierson et al, 1990;McLaren et al, 1996), roadside point sampling, across-the-road remote sensing (Lawson et al, 1990;Bishop et al, 1993;Stephens, 1994;Stedman, 1996;Woods, 1996;Zhang et al, 1996), and instrumented vehicles (Schurmann and Staab, 1990;Kelly and Groblicki, 1993;Guenther et al, 1996) have noted the inadequacies of using laboratory data to estimate real-world pollutant levels. These inadequacies are generally attributed to factors such as the limitations of the test driving cycle, vehicle tampering, poor vehicle maintenance, and the high frequency of`o -cycle' driving events under actual driving conditions (Black, 1991;Ross, 1994).…”

“…For example, the on-road infrared analyzers (Lawson et al, 1990;Bishop et al, 1993;Stephens, 1994;Woods, 1996;Zhang et al, 1996), while important for identifying gross polluters, take a single 0.5 s analysis of an automobile's exhaust and may not be indicative of emission levels under all driving modes (acceleration, deceleration, idle, cruise, highway speeds). Inspection/maintenance program smog-check inspections provide data on in-use vehicles, but are inadequate indicators of on-road emissions since the tests are performed over only two no-load engine operating conditions (2500 rpm and idle).…”

Characterization of Hazardous Solid Waste (Soot) Accumulated in Tailpipe of Typical Indian Share Autos

“…Share autos running with more than allotted capacity consume more fuel resulting in higher emissions [2][3][4] . Inadequate maintenance of vehicles enhances emission from them [5][6][7][8][9] . Besides, lack of controlling devices like catalytic converters and filters makes them even larger emitters of pollutants, especially soot particles.…”