Operating habits can make a lasting difference in fuel economy
February 1, 2013
Truck, engine and component manufacturers have introduced a long list of vehicle enhancements in the name of saving diesel. Everything from aerodynamic fairings to engine speeds and tires are being tweaked to reduce a truck’s thirst for...
Truck, engine and component manufacturers have introduced a long list of vehicle enhancements in the name of saving diesel. Everything from aerodynamic fairings to engine speeds and tires are being tweaked to reduce a truck’s thirst for this liquid gold.
But few of these enhancements will make a bigger difference than the person sitting in the driver’s seat. Natural Resources Canada’s FleetSmart program suggests that fuel economy can vary by as much as 35% when comparing the actions of different drivers within the same fleet.
Indeed, the foot sitting on the accelerator may make the biggest difference of all. On its own, the 10 km/h drop between 100 and 90 km/h can equate to a 10% improvement in fuel economy.
A close eye on the tachometer can be just as important as the needle on the speedometer.
Newly licensed drivers who are familiar with cars that have red lines around 7,500 rpm often tend to over-rev diesel truck engines which have red lines closer to 1,500 rpm. Even experienced drivers need to adjust their habits. Just over a decade ago, an engine’s sweet spot would likely have them cruising along at 1,600 rpm. The latest engines can offer better fuel efficiency at 1,450 rpm or lower.
There should be little surprise that these engine and road speeds can make a difference. The less we have to push on the pedal, the less fuel we’re dumping into the engine. If you have a driver who is down on the boards every time he’s taking off, versus a guy who’s gently opening the throttle and releasing it between shifts, that second person is going to have a lot better success.
The most fuel-efficient gear changes, meanwhile, will involve a practice known as progressive shifting, which involves shifting from one gear to the next at the first opportunity, using a gentle touch of the accelerator every step of the way.
The same driving habits that consume less fuel will support fleet safety programs. Defensive drivers are always coached to monitor the traffic and hazards appearing up the road, and maintain a safe cushion of space around the truck. This reduces the chance of a collision, but it also reduces the need to apply the brakes and allows the truck to remain moving under its own momentum, rather than wasting the fuel needed to start rolling after a full stop.
Activities like these obviously happen far away from a fleet yard, but managers can monitor driving habits by tapping into the data stored on an engine’s Electronic control unit (ECU). An ECU, for example, will record the number of hard stops that occur as the truck’s speed drops more than 11 km/h per second. This corresponds with times when a driver is not leaving enough following distance and making too many panic stops. The same black boxes will offer data about everything from vehicle speed, to engine speeds in specific gears, and the time spent in cruise control. They are factors that can make a difference for safety and operations managers alike.
The potential fuel savings are not limited to a moving truck, either. Idle time can often be reduced, even in the coldest weather. The engine coolant itself will warm up in a mere five to seven minutes, after which the truck can begin to move.
Other components such as tires will actually warm up more quickly when a load is applied.
It is not the only change that can reduce idle time. Auxiliary power units and bunk heaters all consume less fuel than an idling engine. Trucks on selected routes can even take advantage of shorepower systems being installed in selected truck stops.
Operations teams and drivers can also join together in the trip planning that will make an ongoing difference. Sometimes a slightly different route or departure time can help to avoid a major storm, limiting the wind, rain and snow that can influence aerodynamic drag. Drivers, meanwhile, can be coached to keep their tires in the ruts on a snow-covered highway, and reduce their speeds every kilometre along the way. By reducing your speed, you’re not displacing the wind quite as much.
They are valuable habits, and many fleets are compensating drivers with fuel bonuses because of it. Any identified goals simply need to be within reach to ensure a program’s ongoing success, using benchmarks based on similar trucks in similar lanes. After all, a four-axle tractor-trailer will not perform the same way as a tandem-tandem combination; the journeys through Saskatchewan will be easier on a fuel tank than a trip through the foothills of Alberta. As for the timing of incentive payments, think of making it quarterly or monthly in case the driver has a day off.
Think of it as yet another strategy that will help to address a long list of burning issues.
– This month’s expert is Jason Shiell. Jason is a senior risk services consultant for Northbridge Insurance, and has more than 20 years’ experience in the trucking industry as a driver, certified fleet driver trainer, risk manager and more. Northbridge Insurance is a leading Canadian commercial insurer built on the strength of four companies with a long standing history in the marketplace and has been serving the trucking industry for more than 60 years. You can visit them at www.nbins.com.