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21st Century Truck Initiative/Partnership (21CTP)

Idle Reduction

Interest in idle reduction among industry partners was to be shared by both the engine manufacturers and the truck manufacturers. Engine manufacturers would work on engine subsystems to enable electrification of many truck accessories, while truck manufacturers would focus on integration of the idle reduction components into the truck. The Department of Transportation (DoT) and the Environmental Protection Agency (EPA) had been tasked in the National Energy Plan to lead federal efforts for idle reduction research to reduce emissions and fuel consumption from idling trucks. The DoT and EPA programs were focused on working with fleets and manufacturers to install and use these technologies. The Department of Energy (DoE) was also participating in the idle reduction initiative through research in idle reduction technologies and truck accessory electrification. The DoE was leveraging its resources through development of idle reduction technologies including fuel cell auxiliary power units (being created at the Hydrogen, Fuel Cells, and Infrastructure Technologies office at DOE). The Department of Defense was researching idle reduction technologies to ensure reliable power sources and silent operation when needed in combat situations.

Long-haul trucks have historically idled significant portions of the time. A typical long-haul truck as of 2006 idles an estimated 1,800-2,400 hours per year when parked overnight at truck stops and other rest areas (e.g., borders, ports, warehouses, and terminals). Nationally, a significant amount of fuel has been consumed unnecessarily this way. Class 7 and 8 trucks alone consume about a billion gallons of diesel fuel annually during overnight idling. Drivers have many reasons for keeping the diesel engine running in a tractor-trailer: (1) to keep the cab and/or sleeper heated or cooled, (2) to keep the fuel warm in winter, (3) to keep the engine warm in the winter to permit easier startup, (4) to provide power to operate electrical appliances such as microwaves and TV sets, (5) to keep the batteries charged, and (6) because the other drivers do it. The focus has generally been on overnight idling, which represented a very visible target for conservation and emission reduction efforts. In addition, commercial vehicles of all sizes also idle for extended periods during their workdays, often creeping along in queues at ports and depots, and the quantity of petroleum used for workday idling was thought to be far greater than that used by sleepers overnight. The sum of overnight and workday idling of trucks was estimated to consume well over 2 billion gallons of diesel fuel annually in the United States. Other vehicles with diesel engines are also idled for long periods: school bus drivers idle their buses in the morning to defrost the windshield and heat the bus, and transit and tour bus drivers idle their buses to heat or cool the bus while waiting for passengers. Off-highway vehicles and locomotives are idled to keep the engine and fuel warm in cold weather. Military vehicles spend a significant amount of their engine on-time idling to provide power to their hotel loads, communication, and weapons usually as part of a stealthy silent watch operation.

Idling produces airborne emissions and noise in addition to excess fuel consumption. Air quality at and around truck stops, and in the truck cab itself is often poor, and noise levels make it difficult for truckers to sleep. A number of cities and municipalities banned or restricted idling to reduce these impacts. For example, Philadelphia bans idling of heavy-duty diesel-powered motor vehicles, with exceptions made during cold weather. Some of the states and districts with idling regulations as of December 2006 include: California, Colorado, Connecticut, Hawaii, Illinois Maryland, Massachusetts, Minnesota, Missouri, Nevada, New Jersey, New York, Pennsylvania, Texas, Utah, Virginia, and Washington, D.C. Although many of these ordinances are not strictly enforced, Boston and New York City were among the localities that had started enforcing anti-idling regulations more aggressively. California's Air Resources Board adopted a rule that not only limited idling to 5 minutes, but also required automatic shut-off devices beginning in 2007.

Extended idling by commercial trucks costs truck owners about three billion dollars annually and wastes over 1% of our petroleum resources. Much of this petroleum use could be avoided by installing idle reduction technologies, adopting more efficient freight scheduling policies, or in some cases, simply turning the trucks off. Reducing idling would improve the durability of the vehicles and result in maintenance cost savings by reducing engine-on time and the frequency of oil changes, as well as increasing the interval to engine overhaul. The main reason for interest in idling reduction has been that idling wastes diesel fuel, and the price of diesel fuel was high in 2006 and extremely unpredictable. Truck owners started installing idling reduction devices, and the 21st Century Truck Partners were working to accelerate achievement of the potential energy savings and emission reductions.

The goal of this strategic element of the 21st Century Truck Partnership was to reduce fuel use and emissions produced by idling engines. The first four objectives that would enable achievement of the goal were grouped together because they are inter-related. The objectives as of December 2006 were to:

  • Establish an industry/government collaboration to promote the research, development, and deployment of cost-effective technologies for reducing fuel use and emissions due to idling of heavy-duty diesel engines.
  • Establish an educational program for truck and bus owners and operators to implement the most costeffective enabling technologies and operational procedures to eliminate unnecessary idling.
  • Develop a mix of incentives and regulations to encourage trucks and buses to find other more fuel-efficient and environmentally-friendly ways to provide for their power needs while at rest.
  • Facilitate the development of consistent electrical codes and standards that apply to both on-board and stationary electrification technologies.
  • Develop and demonstrate add-on idling-reduction equipment that meets driver cab comfort needs, has a payback time of 2 years or less, and produces fewer emissions of NOx and PM than a truck meeting 2010 emission standards, by 2009.
  • Develop a truck with a fully-integrated idling-reduction system to reduce component duplication, weight, and cost, by 2012.
  • Develop and demonstrate a viable fuel cell APU system for on-road and off-road transportation applications, in the 5-30 kW range, capable of operating on hydrogen directly, or using a carbon-based fuel with a reformer.

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Page last modified: 07-07-2011 02:41:30 ZULU