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Abstract The world has 1.4 billion passenger vehicles. How should governments regulate their air pollution emissions? A Pigouvian tax is technologically infeasible. Most countries instead rely on exhaust standards that limit air pollution emissions per mile for new vehicles. We assess the effectiveness and efficiency of these standards, which are the centerpiece of U.S. Clean Air Act regulation of transportation, and counterfactual policies. We show that the air pollution emissions per mile of new U.S. vehicles has fallen spectacularly, by over 99%, since standards began in 1967. Several research designs with a half century of data suggest that exhaust standards have caused most of this decline. Yet exhaust standards are not cost-effective in part because they fail to encourage scrap of older vehicles, which account for the majority of emissions. To study counterfactual policies, we develop an analytical and a quantitative model of the vehicle fleet. Analysis of these models suggests that tighter exhaust standards increase social welfare and increasing registration fees on dirty vehicles yields even larger gains by accelerating scrap, although both reforms have complex effects on inequality.
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Environmentally Responsible Lightweight Passenger Vehicle Design and Manufacturing
Abstract The mass reduction of passenger vehicles has been a great focus of academic research and federal policy initiatives of the United States with coordinated funding efforts and even a focus of a Manufacturing USA Institute. The potential benefit of these programs can be described as modest from a societal point of view, for example reducing vehicle mass by up to 25% with modest cost implications (under $5 per pound saved) and the ability to implement with existing manufacturing methods. Much more aggressive reductions in greenhouse gas production are necessary and possible, while delivering the same service. This is demonstrated with a higher-level design thinking exercise on an environmentally responsible lightweight vehicle, leading to the following criteria: lightweight, low aerodynamic drag, long-lived (over 30 years and 2 million miles), adaptable, electric, and used in a shared manner on average over 8 h per day. With these specifications, passenger-mile demand may be met with around 1/10 of the current fleet. Such vehicles would likely have significantly different designs and construction than incumbent automobiles. It is likely future automotive production will be more analogous to current aircraft production with higher costs per pound and lower volumes, but with dramatically reduced financial and environmental cost per passenger mile, with less material per vehicle, and far less material required in the national or worldwide fleets. Subsidiary benefits of this vision include far fewer parking lots, greater accessibility to personal transportation, and improved pedestrian safety, while maintaining a vibrant and engaging economy. The systemic changes to the business models and research and development directions (including lightweight design and manufacturing) are discussed, which could bring forth far more sustainable personal transportation.
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- Award ID(s):
- 2133630
- PAR ID:
- 10447037
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Automotive Innovation
- Volume:
- 6
- Issue:
- 3
- ISSN:
- 2096-4250
- Page Range / eLocation ID:
- p. 300-310
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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