Which Is Greener: Idle, or Stop and Restart? Comparing Fuel Use and Emissions for Short Passenger-Car Stops

Most advice to the public about idle-reduction lacks scientific basis and the information in the literature is often inconsistent. Argonne National Laboratory performed some simple experiments to provide a preliminary factual basis for recommendations on when to keep the engine on, and when to turn it off, for the minimum environmental impact. Previous work demonstrated that idling is a very inefficient way to warm up a car (diesel might never...