Britain has experienced a heatwave over the past week with temperatures hitting a record 38.1 degrees on Thursday. This was the hottest day ever recorded in July and caused some travel chaos for people across the country. As a result of this many motorists will have utilised a car’s air conditioning system to keep cool on the roads. Air conditioning systems in cars can help keep you cool in hot weather and are especially useful at higher speeds when putting the window down is impractical.
However, it is commonly known that using air conditioning can increase fuel consumption. How much is fuel consumption affected when you use a car’s air conditioning?
Air conditioning can add up to 10 per cent to fuel consumption and is especiallyy apparent at lower speeds.
The AA said: “Air con could add up to 10% to fuel consumption – the effect is likely to be more noticeable on short trips when it’s got to work harder to cool the car in the first place than on longer journeys where it’s just keeping the car cool.
“If you return to a hot car it’s best to open all the windows when you first drive off to clear the hot air before closing them and turning the air con on – the air con won’t have to work so hard and you’ll cool the interior more quickly.
“If you’re really hung up on fuel economy then around town at low speed, driving with the windows open is an option instead of using the air con – but at higher speeds this will cause so much additional drag that closing the windows and using the air con will be the cheaper option.”
According to airconco.com, motorists should be opening their windscreen at speeds up to 55mph to save fuel economy.
The website states: “It is more economical to open your windows up to speeds of around 55mph as running the a/c at low engine speed creates extra stress and demand resulting in increased fuel consumption.
“Above 55mph, it’s better to run the air con as opposed to the extra drag caused by open windows.
“It adds car accessories will drain your battery so you should try and limit this to save power for when it’s needed.”
If your air conditioning is not working or faulty then you can get it serviced for around £20.