Topics
1 Comment
-
Re: Idling Research
2009-02-20 11:36:38 UTC
I look at idling, whether it be from a passenger car to a diesel truck, as an environmental problem FIRST and an economic concern last. Heres why:
1. One minute of idling produces more carbon monoxide than smoking three packs of cigarettes.
2. Ford Motor company says: Avoid idling more than 30 seconds (when not in traffic), frequent restarting has little impact on the battery and starter (About $10.00 a year worth of wear), whereas excessive idling can actually damage important engine components.
3. Reducing diesel exhaust emissions can make a significant contribution to cleaner air.
Idling fuel use is approximately 0.6 Liters per hour per Liter of engine displacement.
Source: Review of the Incidence, Energy Use and Costs of Passenger Vehicle Idling.
Office of Energy Efficiency, Natural Resources Canada, 2003. (They tested numerous vehicles to come up with an estimate of idling fuel use per Liter of engine displacement.)
This is equal to 0.1585Gal/hr/L of Engine Displacement
1Gallon = 3.785 Liters
5 min x 365 days = 30.4 hours
Some examples of idling fuel use per hour, and resulting annual fuel use from 5 minutes per day of idling:
Vehicle model Engine displacement Fuel use per hr. of idling Annual use
Honda Fit 1.5L 0.24 gal 7.3 gal
Ford Focus 2L 0.32 gal 9.6 gal
Ford Explorer 4L 0.63 gal 19.2 gal
Ford Expedition 5.4L 0.86 gal 26.1 gal
Ford F-350 6.8L 1.08 gal 32.8 gal
The numbers that NRC came up with match what others sources say as well--about 1/3 gal/hr for small cars, up to 0.75gal/hr for trucks/SUVs, and 1 gal/hr for larger/commercial trucks. (Here is a site with similar estimates, for example: http://www.thehcf.org/antiidlingprimer.html)
From what Ive been told pretty much everything holds true for diesels, certainly the fuel use estimate. (The cigarette comparison is an estimate for a regular passenger car, so a larger vehicle would be more). The Fords (and others) 30 second rule is for passenger vehicles, not big trucks/buses, but should not be significantly different for a warmed up diesel engine. Below is a quote from Caterpillar, which is pretty identical to what the other Truck/bus/diesel-engine manufactures say. Heavy Duty Trucking Magazine recommended that Truckers turn their engines off waiting for trains and even at long red lights (!!we dont recommend that). So it might be a 45second or 1 minute rule for a small diesel or something slightly different if someone really did the calculations, but it should be safe to say that a Dodge Ram certainly shouldnt need to idle more than a semi truck.
Go to Google and type in Brown cloud Denver. Gross, no? 2% of the vehicles in Denver are diesel. Diesel exhaust contributes 15-23% of the fine particle-matter pollution in the entire region. This nastiness in our air causes respiratory problems in the young, elderly, and those with pre-existing aliments. 25-40% of the brown cloud comes from diesel exhaust.
From the Caterpillar Motor Coach Engine Performance Guide:
A diesel engine consumes approximately 1 gallon of fuel per hour at a fast idle (900 1000 RPM). Idling consumes valuable resources (fuel) and for the most part is unnecessary. Excessive idling can contribute to carbon build-up and / or engine slobber and is detrimental to the engine.
Engine Warm-up The best and fastest way to warm-up an engine is to begin driving at part load and part throttle shortly after start-up, following a brief inspection of the coach.
Engine Shut-down Before exiting the highway, take your foot off the throttle and coast long enough to decelerate the coach to the point where a minimum amount of braking is required to exit the main roadway. A heavy coach can coast a long distance with the drivers foot off the throttle. During the coasting period the engine is not consuming any fuel. With a light load on the engine for a period of two to three minutes, the engine has cooled sufficiently and can be shutdown.
Thanks Matthew!
Tiffany Rice
Superhero of anti-idling
United States
0 Recommends
You haven't saved any recommendations.
Messaging 0 colleagues