It is common to see big trucks standing with their engines running. In fact it is estimated that idling times for individual trucks range from 350 to 2000 hours every year.
The cumulative effects of idling are
- Enormous fuel wastage estimated at about $2.5 billion a year
- Increased frequency of service intervals
- Reduced engine life
- Reduced life of internal parts
- Air pollution
- Noise pollution
Current manufacturers of diesel engines recommend no more than three minutes of warm up time. Manufacturer manuals warn that if the engine is parked for more than 5 minutes, it should be shut down as excessive idling can cause carbon buildup damaging the engine. They also state that idling reduces fuel economy and oil life.
Vehicle emissions are the leading source of toxic air pollution and have been linked to increased rates of cancer, heart and lung disease, asthma and allergies. The toxicity of diesel exhaust emissions has prompted most states to pass ordinances on idling with most of them not allowing idling for more than 3-5 minutes.
Idle reduction technologies that allow for quick warm up and better fuel efficiency pay for themselves. The government is also helping to pass laws that promote less idling.
Auxiliary power units allow a truck to provide heating and cooling for the driver during his rest periods without the need to keep the engine idling. However these units weigh almost 400 pounds which translates into less freight that a truck can carry. As per a new law that goes into effect on November 28,2010, trucks can install auxiliary power units (APUs) without diminishing the amount of freight they can legally carry.
This will encourage commercial fleets to install them not only preventing exhaust emissions but also significantly saving fuel consumption.