Scania Fuel Duel counts the cost of speed.
Scania has conducted a scientific experiment to help transport operators understand the benefits of travelling at 90 km/h instead of 100 km/h.
The Scania Fuel Duel was a two-day driving activity that saw two identical Scania R 560 V8-powered prime movers pull b-double sets from Melbourne to Sydney and back, loaded to 59 tonnes GCM.
The vehicles were driven by two highly experienced Scania Driver Trainers, with one vehicle travelling up to Sydney from Melbourne at 90 km/h and the other travelling at up to 100 km/h.
In Sydney the vehicles had their speed limiters reversed, so the vehicle that travelled up at 90 km/h returned at 100 km/h and vice-versa.
During the return journey, Scania invited the Australian Trucking Association Chief executive Stuart St Clair to sit in as a passenger in one vehicle, while Prime Mover Magazine editor Peter Armstrong rode in the other.
“This experiment is very important because it shows quite clearly the relationship between cruising speed and fuel consumption, and of course, carbon dioxide emissions,” said Roger McCarthy, Managing Director of Scania Australia.
“With the impending Carbon Tax, and greater environmental awareness, Scania feels the time is right to reignite the debate around the benefits of voluntarily reducing cruising speed limits.
“We also know that travelling at 90 km/h offers drivers additional time to help them avoid an accident, plus reduce braking distances as well as reduce fatigue.
As a result of the drive Scania was able to determine:
Total journey distance: 768 km each way, 1536 km round trip
From Melbourne to Sydney, the truck travelling at 100 km/h used 45 litres more fuel than the truck travelling at 90 km/h (494 vs. 449-litres)
From Sydney to Melbourne, the truck travelling at 100 km/h used 11 litres more fuel than the truck travelling at 90 km/h (486 vs. 475-litres). The long uphill climbs out of Sydney adversely affected the truck travelling at 90 km/h more than the truck travelling at 100 km/h due to the difference in momentum.
From Melbourne to Sydney, the truck travelling at 100 km/h emitted 118 kg more carbon dioxide than the truck travelling at 90 km/h (1308 kg vs. 1190 kg)
From Sydney to Melbourne, the truck travelling at 100 km/h emitted 30kg more carbon dioxide than the truck travelling at 90 km/h (1290 vs. 1260 kg)
From Melbourne to Sydney, the average speed across the entire journey was
85 km/h for the truck limited to 100 km/h and 77 km/h for the truck limited to 90 km/h.
From Sydney to Melbourne, the average speed across the entire journey was
88 km/h for the truck limited to 100 km/h and 80 km/h for the truck limited to 90 km/h.
From Melbourne to Sydney the differential in actual driving time amounted to 40 minutes.
From Sydney to Melbourne the differential in actual driving time amounted to 53 minutes.
While the fuel saving on the outward journey amounted to 10 percent, the overall round trip saving was 6 percent.
As a real world example, for a vehicle travelling the Hume five times each week (a distance of 768 km per trip, 3840 km in total) over the course of a year, an operator could save around $10,000 per vehicle (at a diesel price of $1.27 per litre taking into account the diesel fuel rebate) running at 90 km/h instead of 100 km/h.
“From an operator’s perspective the financial savings would add up to a substantial sum each year, per truck,” Roger says. “This goes straight to the bottom line.
“If you were to multiply that across a fleet you can quickly see the magnitude of the savings. Then if you take into account the CO2 savings as well as the potential for greater levels of road safety from drivers travelling slightly less fast being able to have better reaction time, you can see that it is a win-win-win situation.”
Stuart St Clair, ATA Chief Executive said that travelling at 90 km/h did not seem slow.
“The way the engine handled its torque was beautiful, I loved the smoothness of the gearchanges. There was less fatigue, and less distraction.
“If the industry is serious about saving fuel, this is one way. Another is driver training, and an auto gearbox. But lots of drivers still like to rev engines.