Idling Reduction:
Background

Why do trucks and locomotives idle?

Truck drivers idle their engines for a variety of reasons.  First, and foremost, is the need for heating or air conditioning. Beyond the need for a comfortable temperature, truck drivers idle the engine to operate on-board electrical appliances, such as a television or refrigerator.  Another reason for idling is to ensure the engine block, fuel and oil remain warm in cold weather.  Note, per Department of Transportation regulations, long-haul truck drivers must rest for at least 10 hours for every 14 hours of driving.

Locomotive operators idle their engines primarily to protect the engine during cold weather.  Since most locomotive engines do not have anti-freeze, temperatures below 40^o F can damage the engine.  These locomotive engines will idle to maintain engine coolant, fuel, oil, and water warmth, as well as maintaining battery charge.  In addition, they may idle to maintain comfortable temperatures inside the operator cabs. Other reasons to keep a locomotive idling include having a readily available engine (avoiding unnecessary starting and shutting-down), and the habit or custom of always keeping a diesel engine operating.

What is the extent of idling? How long? How many?

An estimated 500,000 long haul trucks will idle their engines for extended periods.  On average, truck drivers will idle for about 8 hours per day, over 300 days per year.  With locomotives, Class I railroads report about 20,000 locomotive engines.  Of this number, about 5,000 are committed to rail yards and are known as "switchers."  Switcher idling is about 2,500-3,000 hours per year.