There’s no doubt that the vehicle you select has the largest impact on fuel economy. However, did you realise that factors you could influence could garner as much as a 45 per cent reduction in fuel consumption?
A report by Michael Sivak and Brandon Schoettle at the University of Michigan Transportation Research Institute points to factors a driver can control including route selection; vehicle load; vehicle maintenance; and the driver’s own behaviour; as crucial factors in determining a car’s fuel economy.
It also suggests that increased efforts should be directed at increasing vehicle occupancy, which has dropped by 30 per cent from 1960. The average on-road fuel economy in the US for all vehicles in 2008 was 17.4mpg – whereas the average was 14mpg as far back as 1923.
So what factors can influence fuel economy performance?
The report suggests that an out-of-tune engine can increase economy by four-40 per cent; tyres with 25 per cent higher rolling resistance can increase economy by three-five per cent; while tyres under inflated by 5psi has an effect of 1.5 per cent; and improper engine oil, one-two per cent.
There are tactical factors that can have an influence too. For example, route selection based on road type, which is variable; route selection based on grade profile, 15-20 per cent; route selection based on congestion, two-40 per cent; and carrying an extra 100lbs, two per cent.
Finally there are operational efforts that have an influence too. Idling is variable, but driving at very high speeds can affect fuel economy by as much as 30 per cent. Not using cruise control while at highway speeds can have an impact of seven per cent; using air conditioner five-25 per cent; and aggressive driving 20-30 per cent.
