programs / Passenger Vehicles


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 emissions 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 established emission standards for passenger vehicles in the 1960s, different regulatory approaches have been adopted by the United States, Japan, and Europe, and each has been emulated to some degree in other parts of the world. 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. The transportation sector is responsible for about one-quarter of energy-related greenhouse gas emissions worldwide. Passenger vehicles account for just under half of this total, and will remain the predominant source of these emissions for the foreseeable future.

Featured Work



Recently Released

Policy solutions to reduce vehicle exhaust emissions under real-world driving conditions
Proposes a rapid, comprehensive policy response not only to deal with defeat devices but also to identify vehicle models with high real-world emissions relative to test-cycle performance and improve current compliance and...
Transition to a global zero-emission vehicle fleet: A collaborative agenda for governments
Surveys governments', automakers', and advocates' efforts to support development of the global EV market, and outlines an agenda to promote the global transition to a zero-emission vehicle fleet.
White paper
From laboratory to road: A 2015 update
Extends an analysis of the gap between official and real-world fuel consumption and CO2 emission values for passenger cars in Europe and investigates the reasons for the increasing gap.
White paper



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From the ICCT Blogs

Dispelling some myths about the gap between test-lab and real-world vehicle CO2 emissions
An explanation of what has and has not caused the gap between test-lab and real-world vehicle CO2 emissions to increase by over 30 percentage points in just over a decade.
Staff Blog
Global milestone: The first million electric vehicles
Sometime this month, somewhere in the world, the millionth modern electric vehicle will hit the road. And in NYC, farsighted governments of the new International ZEV Alliance are coming together to spur deployment of the next million, and more.
Staff Blog
Brazil is not ready for diesel cars
Brazil should hold the line and continue to ban sales of diesel passenger cars.
Staff Blog

The Staff

Anup Bandivadekar
Anup Bandivadekar
Program Director / India Lead
John German
John German
Senior Fellow / US Co-Lead
Hui He
Hui He
Senior Policy Analyst / China Co-Lead
Fanta Kamakaté
Fanta Kamakaté
Chief Program Officer
Peter Mock
Peter Mock
Europe Managing Director / EU Lead