The California Air Resources Board (ARB) will propose requiring diesel trucks with a gross vehicle weight greater than 14,000 pounds be equipped with a non-programmable engine shutdown system that automatically shuts down the engine after five minutes of continuous idling with the goal of reducing emissions.
Trucks with a diesel engine that utilize the idle shutdown system would need to provide other methods—such as an APU—for heating/cooling the cabin and powering accessories when the truck is not being driven.
The new engine requirements would apply to 2008 and subsequent model year diesel engines. Pre-model year 2008 trucks may need to retrofit.
To avoid incorporating a new engine shutdown system, an engine manufacturer may certify an engine to a NOx idling emission standard of 30 grams per hour. This option is proposed because it may be possible to control NOx emissions during idling. However, this option isn’t likely to become available prior to 2010 because that is when more advanced NOx controls are expected to be used for all heavy-duty engines. (Earlier post.)
If manufacturers succeed in developing engines which meet the NOx idling emission standard, operators would be allowed to idle the main engine continuously to provide cab comfort and electrical power during rest periods, and would not need to install alternative cab comfort devices. However, they would still be subject to the existing five- minute idling restriction when the truck is located within 100 feet of a restricted area.
ARB staff estimates that statewide emission reductions as a result of the policy would be approximately 46 tons per day (tpd) of NOx, 4.2 tpd of ROG, 1,930 tpd (0.7 million tons per year) of carbon dioxide (CO2), and 0.42 tpd of PM emissions in 2010.For the South Coast Air Basin (including the Los Angeles region), the corresponding emission reductions are estimated as 18 tpd of NOx, 1.6 tpd of ROG, 740 tpd (0.3 million tons per year) of CO2, and 0.15 tpd of PM in 2010.
A public hearing on the proposal is being held on 20 October.
CARB staff Initial Statement of Reasons