Drivers warned about button that increases fuel usage by 10%

Experts have warned UK drivers to avoid pressing a certain button in their cars as it could increase fuel usage by up to 10 percent.

Amid the cost-of-living crisis, fuel prices have continued to skyrocket, with the RAC's latest figures showing the average cost of a litre of petrol and diesel sits at 175.77p and 186.41p respectively.

With experts now fearing that price could soon hit £2 per litre, drivers are looking to save money where they can.

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And as much as you might want to blast your AC at this time of year, experts have suggested to use the button sparingly, as it could increase your fuel usage by up to 10 percent.

Chris Evans, head of content at leasing.com, highlighted the issue while referencing a 2004 study by the Society of Automotive Engineers (SAE) on the impact of windows open vs air conditioning in larger saloon cars and SUVs.

While using this feature certainly takes its toll on your fuel tank, in some cases having your windows open while driving at high speeds could actually be worse.

Chris explained that the reason for this is down to increased drag, which requires more power from the engine.

Although the referenced research looked at larger vehicles, other studies have shown that the issue is exacerbated in average-sized cars.

If you're wondering how to avoid a high level of drag, Chris suggested: "The 45mph (70kmph) 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."

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But while the 45mph rule is a good guide, what should you do if you're in bumper-to-bumper traffic?

"In these situations, it is probably best to avoid using air con or opening your windows," he added.

"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."

Motorists could also try tinted windows, which significantly reduce the heat given off by sunlight inside of a car.