Every drop of fuel counts

In uncertain times, fuel efficiency comes even more into focus for operators and hauliers. Here Scania experts share their tips on how to save money with fuel efficiency.

TEXT: PER-ERIK NORDSTRÖM AND PER-OLA KNUTAS

Drivers and fuel today account for more than half of the costs for a typical operator. So fuel efficiency has a large impact on an operator’s business and capacity to earn money.

This is obvious to Erik Dahlberg, who works within Scania’s Research and Development. “Scania has a long tradition of putting every conceivable effort into optimising the vehicles’ fuel economy. It permeates all our development projects, from nuts and bolts to cab design.”

But now, Dahlberg says, there is also an increased interest from operators. Today they spend a lot of time discussing the most fuel-efficient vehicle specifications with their sales representative. “They are often down to adjusting the last decimal,” he says.

Here are some realistic steps toward optimising fuel performance that are available to most operators. But, says Dahlberg, “there is no magic formula, so it’s the constant engaging in details that counts.”

Keep the vehicle in shape

  • Continuous monitoring of vehicle and driver performance makes it possible to take action with minimum delay.

  • Regular maintenance takes on a crucial role to make sure everything stays in optimum shape; faults can be detected before they have a chance to cause much harm.

  • Get the gearing right for the application. At 40 tonnes with today’s high-torque engines, going for economy gearing, i.e. cruising below 1200 r/min instead of 1350 r/min, will save up to 3 percent of fuel without any severe effects on driveability.
     

  • Keeping down the unladen weight will automatically save fuel. Specifying low-weight options could reduce weight by 500 kilograms and save up to 1.5 percent in hilly terrain.

  • Checking axle alignment pays off. Adjusting a 1 degree misalignment may save up to 3 percent of fuel.

Tyre pressures

One bar too little in the tyres may cost up to 2 percent of fuel. Keeping up the tyre pressure at all times will secure consistent rolling resistance, minimum tyre wear and maximum road safety. An easy way is to specify tyre pressure monitoring (TPM), a system that allows pressures to be read from the cab and that alerts the driver if the pressure drops in any of the tyres. In addition, around 5 percent of fuel can be saved by specifying tyres with low rolling resistance.

Electronic support

Automated gearchanging makes driving easier and helps drivers perform consistently, while reducing wear and tear on the vehicle. Scania Opticruise has been found to save up to 10 percent of fuel for an untrained driver.

Scania Ecocruise, the smart cruising software, can save 4–5 percent on top of that by using techniques well known to any driver trained in eco-driving – and with negligible time loss in a working day. Not accelerating when climbing a hill until the crest levels out and using momentum at the bottom of slopes are two of the secrets.

Scania has also developed acceleration control, a system that promotes smooth driving and boosts passenger comfort in city buses. It also reduces wear and tear on brakes and powertrains and typically saves up to 6 percent of fuel. Though developed for city buses, it will also save fuel for some urban distribution applications.

Air drag

  • Fitting air deflectors is the first obvious step in improving air drag on a tractor unit. This alone saves some 10 percent. But further refinements are possible:

  • Adjusting the roof air deflector from 10 cm too high or low will save up to 3 percent of fuel.

  • Fitting Scania’s rubber extensions on the side air deflectors and sideskirts will save up to 1.5 percent. 

  • Avoiding auxiliary lights, air horns and other embellishments on the roof will save up to 1.5 percent.

And then all sorts of improvements are possible on the semitrailer, of course. A difference of 5 percent in fuel consumption between semitrailers is not uncommon.

Driver training     

Fuel savings of 10 percent on average are possible as a result of professional driver training.
Active monitoring of driver performance and regular training are needed to maintain this level.

Lower speed                 

A simple measure like lowering the normal highway cruising speed by 4 km/h will save around 5 percent of fuel.


Potential

  • Within each area – driver, vehicle, service, there is a saving potential of up to 10 percent. The figures cannot be added up, however, they give an indication of the effect of individual actions.

  • Counting conservatively, for a typical 40-tonne European combination running 200,000 km annually, a fuel saving of 10 percent can be translated into 6,000 litres (approx EUR 6,000).