US trucking firms are bitterly complaining about the price of diesel, but their apparent reluctance to actually help themselves means they aren't going to get any sympathy from me.
According to the Energy Information Administration the average price of diesel in the US is $2.55 (£1.40) a gallon . While this might seem like a bargain to us in rip-off Britain, it has come as a major shock to a country which up until a few years ago was paying a little over a dollar (60p) for a gallon. With this in mind you would think that American operators would do their best to become as fuel efficient as possible, but I certainly didn't see any evidence of this on a recent trip to the US.
I was amazed by the lack of aerodynamic aids on Class 8 trucks. According to the UK Government's free help booklet entitled The Streamlined Guide to Truck Aerodynamic Styling , sticking aerodynamic styling features on a truck used on long distance routes can lower fuel consumption by 6-12%. So why hasn't somebody told the Americans this? Roof deflectors are far less common than in Europe, and many of the tractors that are fitted with them have them set at totally the wrong height. According to AB Volvo's product manager of aftermarket marketing Holgar Markgraf, the difference between a low angle and the correct angle is one US gallon per 250 miles.
Others, like the truck photographed below, have permanent roof spoilers built into the cab, which have a detrimental affect on fuel economy when used with a flat trailer. Cab collars, side vane extensions and front bumper air dams are few and far between, while not many tractors have skirts to prevent air from entering the cavity between the front and rear tractor wheels.
Semi-trailer aerodynamics are worse still, and I don't remember seeing a single side skirt on my 2,000-mile roadtrip. American hauliers would also do well to close the gap between the tractor and trailer. The more air that can travel beneath the trailer, the more turbulence is created. Jeff Bird, who is in charge of Volvo's truck press test fleet in Gothenburg, Sweden, says the addition of skirts will boost fuel efficiency by 2%. Christian Salvesen experienced a 2% reduction in its fuel bill after specifying them on its curtainsider trailer fleet (Motor Transport 21/10/04).
Of course some of the blame must also fall on truck manufacturers, who continue to peddle ancient designs with house-like aerodynamics. This photo of a late 1920's Ford Model AA truck and a late 1990's Freightliner FLD shows just how little the basic American truck design changed in 70 years.
Ignore the optional roof spoiler, and the basic shape is unchanged.
But even with terrible aerodynamics US hauliers could make a huge difference if they just slowed down. It's not uncommon to be overtaken at 80mph by a fully-laden artic on the interstate. UK container haulier Deben Transport has recently discovered that lowering its speed limiters from 56mph to 52mph improves fuel economy by 0.5mpg, so you can imagine what a huge difference the introduction of limiters would have in the USA.
My advice to all those moaning Americans is to send your fleet managers over to Europe for a free lesson in fuel economy.
Comments (1)
is rather overstated. The new truck has rounded front corners and a roofline (including sleeper with wings) that reduces trailer drag. It is not the most aerodynamic model long on the road, noteably the Kenworth 2000 model has a much sleeker nose, albeit only some trucks are of that sleek a design - but many now on the road are still better than the illustrated truck.
Posted by Keith Sketchle | May 5, 2008 4:44 AM
Posted on May 5, 2008 04:44