Drivers must avoid this button or see fuel consumption soar by 20 percent | Personal Finance | Finance
Drivers warned to avoid one button as it ‘increases fuel consumption by 20 percent’. (Image: Getty)
With temperatures beginning to rise and fuel costs continuing to bite, many drivers will be looking for ways to keep cool without sacrificing fuel efficiency.
When travelling in warm weather, motorists typically face a choice between winding down the windows or switching on the air conditioning.
Though many drivers underestimate the consequences, both options carry a considerable impact on fuel consumption.
Air conditioning is notoriously energy-hungry, while open windows can increase the vehicle’s aerodynamic drag, making the engine work harder and burn through fuel more quickly.
Although both methods have their merits, there are situations where one option proves far more beneficial for both driver and vehicle.
Chris Evans, Chief Marketing Officer at Leasing.com, highlighted the benefits of using both air conditioning and open windows strategically.
Using the air con can increase fuel consumption by 10 percent. (Image: Getty)
He referenced a 2004 study by the Society of Automotive Engineers (SAE), which investigated the effects of open windows versus air conditioning in larger saloons and SUVs.
The research took into account a wide range of variables, including how far windows were open, the aerodynamic profiles of different vehicles, and how long air conditioning was in use.
He said: “As such, the 45mph figure is a guide, but a fairly good one.
“While all this might seem like a minor issue, getting it wrong can have a notable impact on your fuel economy.
“Using AC can increase your fuel consumption by as much as 10 percent but opening the windows at higher speeds can increase fuel consumption by as much as 20 percent.”
Multiple subsequent studies have been published, including one which found that air conditioning usage affects hybrid vehicle fuel economy more drastically than traditional combustion-only motors.
Additional research, carried out by Emissions Analytics, showed that air conditioning’s impact on hybrid fuel economy was almost twice that of conventional vehicles.
Fuel efficiency dropped by 6.1 percent in a hybrid car on average, in contrast to just 3.8 percent for a standard petrol car and 4.6 percent for a diesel.
Mr Evans added: “While the 45mph line is a good guide, things get a bit more complicated when you are in bumper-to-bumper traffic.
“In these situations, it is probably best to avoid using air con or opening your windows.
“However we know that in hot conditions that might be uncomfortable, so as a solution you could turn on the air con but close your air vents.
“The air con merely recycles the cabin air rather than drawing the air from outside, where there is nose-to-tail line of traffic all belching out exhaust fumes.”
Other approaches for keeping a vehicle cooler without relying on air conditioning include seeking shade or covered parking.
Tinted windows could also prove beneficial for drivers, along with heat deflectors. A car window tint can effectively reduce the heat generated by direct sunlight by up to 70 per cent inside a vehicle.
As the car will stay cooler, drivers may be less tempted to switch on the air conditioning.
