Publication Detail

Benefit-Cost Analysis of a Vehicle Scrappage Program


Presentation Series

Download PDF

Suggested Citation:
Washington, Simon P. (1993) Benefit-Cost Analysis of a Vehicle Scrappage Program. Institute of Transportation Studies, University of California, Davis, Presentation Series UCD-ITS-RP-93-17

Proceedings, 35th Annual Meeting Transportation Research Forum

With the latest series of Clean Air Act amendments, metropolitan planning organizations and air quality management districts are faced with the difficult task of ensuring conformity between transportation projects and air quality management plans. Under the new legislation, industry and manufacturers in California are required to reduce emissions incrementally, and over the long term. In meeting these requirements, polluters can choose technology options, or may choose to reduce emissions elsewhere in the basin, so long as they meet their net loss emission requirements. One way to minimize technology costs, or in some cases, to delay costs of technological measures, industry can propose emission offsets in other sectors. One of these sources of emissions is mobile sources.

An example of an offset proposed for reducing mobile source emissions is vehicle scrappage programs, an example being the Southern California Retired Automobile Program (SCRAP), executed by UNOCAL on June 1, 1993. In these programs, 'dirty' vehicles are purchased from individuals in the air basin, and removed from the vehicle fleet. The theory is that emissions produced by scrapped vehicles is higher than those produced by their replacement vehicles. The difference in emissions between retired and replacement vehicles is claimed as emission reductions.

Many questions arise as to the 'real' emission reductions realized by a vehicle scrappage program, especially since vehicle manufacturers are already mandated to systematically reduce vehicle fleet emission averages over the next decade or so. Given average fleet turnover rates, how beneficial is a vehicle scrappage program? What are the costs and benefits to society from a vehicle scrappage program? Can we quantify the real emissions reductions from a vehicle scrappage program?

This paper presents a benefit cost analysis for a vehicle scrappage program proposed for the greater Sacramento, California metropolitan area. In performing the benefit-cost analysis, uncertainties are made visible and controversies surrounding scrappage programs are addressed. Conclusions are drawn as to the feasibility, appropriateness, and benefits of such programs.