Idling Reduction
|
|
|
|
Unnecessary school bus idling pollutes the air, wastes fuel, and causes excess engine wear. Fortunately, it's easy to implement practices that reduce school bus idling.
Reduce Pollution
Idling school buses can pollute air in and around the bus. Exhaust from buses can also enter school buildings through air intakes, doors, and open windows. Diesel bus exhaust from excessive idling can be a health concern. Read more about health concerns. 
Wasted Fuel and Money
Idling buses waste fuel and money. When idling, a typical school bus engine burns approximately half a gallon of fuel per hour. School districts that eliminate unnecessary idling can save significant dollars in fuel costs each year.
Engine Wear-and-Tear
School bus engines do not need to idle more than a few minutes to warm up, in fact extended idling causes engine damage. Engine manufacturers generally recommend no more than three to five minutes of idling. Caterpillar Inc. cautions drivers to "... Avoid excess idling. If the vehicle is parked for more than five minutes, stop the engine. Excessive idling can cause carbon buildup and/or excessive idling can cause the engine to slobber. This is harmful to the engine." IC Corporation's engine manual states that "...Excessive idling reduces fuel economy, and may decrease oil life."
 |
|
Reduce idling time-the Savings add up!!
If...
A school bus fleet has 100 buses,
reduces idling time by 30 minutes per bus per day,
uses a half gallon of diesel fuel per hour of idling,
and diesel fuel costs $3.75 per gallon,
...Then what are the annual savings?
Fuel cost = 100 buses x 0.5 hr/day x 0.5 gallons of fuel/hr x $3.75 per gallon x 180 days
SAVINGS = 4,500 gallons of saved fuel and $16,875!!
Based on formula estimates by U.S. EPA, Clean School Bus USA
|
|
Anti-idling strategies:
-
Reduce early morning idling time to limit exhaust build up in bus
-
Designate an area in the school for drivers to wait if they arrive early
-
Position the buses away from school air intake vents so pollution does not accumulate in classrooms
-
Change Bus circuit configuration to run lights and heating/cooling off the battery
-
Limit caravanning-position school buses so tailpipes do not blow directly towards another bus
-
Encourage children to sit near front of bus when not full
Idling Myths |
Myth: |
It's important to warm up the engine with a long idle period, especially in cold weather. |
Fact: |
With today's school bus engines, bus and engine manufacturers routinely suggest a warm up time of less than five minutes. In fact, running an engine at low speed (idling) causes significantly more wear on internal parts compared to driving at regular speeds. |
Myth: |
It's better for an engine to run at low speed (idling) than to run at regular speeds. |
Fact: |
Running an engine at low speed causes twice the wear on internal parts compared to driving at regular speeds. |
Myth: |
The engine must be kept running in order to operate the bus safety equipment (flashing lights, stop sign). It's impossible to run this equipment off the internal circuitry of the bus because the battery will run down. |
Fact: |
Safety equipment can be operated without the engine running through re-wired circuitry for up to an hour with no ill-effects on the electrical system of the bus. |
Myth: |
Idling is necessary to keep the cabin comfortable. |
Fact: |
Depending on the weather, many buses will maintain a comfortable interior temperature for a while without idling. Idling is also not an efficient way to keep the cabin warm. Bus routes should be timed so children and drivers do not need to spend a lot of extra time on the bus when it is not en route, particularly in hot or cold weather. In addition, auxiliary heaters can be purchased and installed to keep the cabin comfortable. |
Myth: |
It's better to just leave the engine idling because a "cold start" produced more pollution. |
Fact: |
A recent EPA study found that the emission pulse measured after the school bus is restarted contains less carbon monoxide, nitrogen oxides, and other pollutants than if the school bus idled continuously over a 10-minute period. The analysis indicated that continuous idling for more than three minutes emitted more fine particle (soot) emissions than at restart. |
|
|
