Passenger vehicles
Since the early twentieth century, passenger vehicles have increased mobility and expanded economic opportunity for billions of people. The number of cars on the road has exploded from five million after World War II to nearly one billion today and is expected to reach two billion in just 20 years. The size and growth of this fleet ensures that passenger vehicles are currently and will remain the greatest single challenge for transportation emissions control.
The reductions in passenger vehicle emissions that have been achieved since the mid-twentieth century are a great environmental success story. Government regulation of tailpipe emission standards and private investments in breakthrough technologies such as the three-way catalytic converter have reduced emissions of nitrogen oxides, carbon monoxide and hydrocarbons by 75 to 90 percent at a relatively small cost to consumers. Since California first successfully legislated emission standards for passenger vehicles in the 1960s, three different regulatory approaches have been adopted by the United States, Japan, and Europe. Significant work remains to replicate these successes throughout the rest of the global fleet.
The massive impact of passenger vehicles on climate also remains to be addressed. According to the United Nations’ Intergovernmental Panel on Climate Change, the transportation sector was responsible for about 23 percent of energy-related greenhouse gas emissions in 2004. Passenger vehicles account for about 45 percent of this total, and will remain the predominant source of these emissions for the foreseeable future. In the European Union, where high fuel taxes have constrained emissions growth, a mandatory standard is in place to reduce emissions to 130 grams of CO2 per kilometer by 2015. In the United States, the federal Environmental Protection Agency has proposed a standard of 250 grams per kilometer for light-duty cars and trucks and medium-duty passenger vehicles, beginning in model year 2012.
The ICCT is helping both jurisdictions reach those targets and develop even more ambitious long-term goals for reducing carbon dioxide emissions. The council is also supporting the development and refinement of fuel economy and greenhouse gas standards in China, India and Mexico, and helping those countries tighten restrictions on conventional emissions from light-duty vehicles.
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Attribute-based efficiency standards
This paper summarizes differences between size-based and mass-based standards and discusses their relative advantages and disadvantages. The authors argue for a reconsideration of the mass-based regulatory framework where it is in use and against its extension into as-yet-unregulated light-duty vehicleCongestion Charging: Challenges and Opportunities
Summarizes congestion-charging programs aimed in reducing motor-vehicle traffic: in-place systems in London, Singapore, and Stockholm; a 1980s pilot program and subsequent follow-on studies in Hong Kong; and a 2007 ICCT-sponsored study of Santa Clara County, California.Feebate best practices
