Motorists are being urged to refuel before Monday wherever feasible as warm weather returns across multiple UK regions, potentially causing increased fuel consumption that may take unwary drivers by surprise.
Met Office Forecast and Temperature Peaks
The Met Office has predicted a spell of hot weather beginning on Sunday and reaching its peak on Monday across London and numerous other areas of the UK, especially southern England. The forecaster expects temperatures could reach 30°C on Sunday, climbing to 32°C on Monday, before settling at approximately 30°C throughout much of the following week.
Many drivers remain unaware that warmer weather presents an unexpected hazard relating to fuel tanks, which could leave them unprepared. When temperatures soar, petrol or diesel depletes more rapidly than usual owing to changes in driver behaviour, and in extreme heat it can even impact fuel efficiency.
Current Fuel Prices and Economic Impact
Petrol prices have climbed substantially in recent months owing to the conflict in Iran, and while there has been a modest easing at filling stations lately, costs remain considerably higher than previously. At present, petrol averages 154.72p per litre, while diesel stands at 174.30p according to the RAC, meaning drivers will be keen to avoid any wastage.
Vehicles consume more fuel in hot weather, both through mechanical factors and motorist habits. Consequently, your fuel gauge might become unreliable and fail to provide an accurate reading of your remaining petrol or diesel, reports the Express.
US Department of Energy Insights on Fuel Economy
According to the US government, motorists are more inclined to adopt behaviours that deplete fuel when temperatures rise, including opening windows and activating air conditioning. The US Department of Energy states: "Hot weather can increase fuel economy - the engine warms up to an efficient temperature faster; summer grades of gasoline can have slightly more energy; and warm air causes less aerodynamic drag than cold air. However, keeping comfortable in hot weather by rolling down the windows or using the air conditioning (A/C) can reduce fuel economy. Running the vehicle's air conditioning is the main contributor to reduced fuel economy in hot weather. Its effect depends on a number of factors, such as the outside temperature, humidity, and intensity of the sun."
"Under very hot conditions, A/C use can reduce a conventional vehicle's fuel economy by more than 25%, particularly on short trips. The A/C's effect on hybrids, plug-in hybrids, and electric vehicles (EVs) can be even larger on a percentage basis."
Advice from PassMeFast and Fuel Finder UK
The additional reason to refuel ahead of warmer conditions is to avoid becoming stuck in congestion during sweltering temperatures. Specialists at PassMeFast.co.uk clarify: "When it comes to topping up the petrol in your car, there are two kinds of people: those who refill as soon as the fuel tank gets to around a quarter full, and those who are happy to drive around with the fuel warning light on. The thing is, when the weather's nice and warm, your car's fuel levels drop a lot quicker than usual. This means you can't rely on your normal estimations of how much time you have left before needing to fill up."
"To avoid getting stuck in the middle of nowhere, or at the centre of a traffic jam on a hot day (both nightmare scenarios), make sure you head to the petrol station in good time. Playing it close to the line is just not worth it if the sun's out!"
Myth Busting and Optimal Temperature for Fuel Economy
Motorists have also previously been warned against filling up their vehicle during hot conditions owing to concerns the car could 'explode' in the sunshine. Fortunately, this isn't a genuine issue and is, in reality, a myth. RAC spokesperson Rod Dennis stated: "There is no truth in this. All fuel systems on passenger vehicles are designed to cope with any expansion of fuel, or vapour coming from the fuel. There is no risk of explosion from filling up a fuel tank fully and drivers should have no concerns in doing so."
Nevertheless, regarding operating a vehicle as economically as feasible, there exists an ideal middle ground between cold conditions and hot conditions where efficiency is at its peak, according to specialists. 20°C will deliver superior fuel efficiency compared to extremely cold conditions, though as temperatures climb higher, these benefits begin to diminish.
Fuel Finder UK states: "According to official fuel economy tests, your car's efficiency drops by around 10% at -5°C compared to 20°C. For short trips under four miles, that penalty can reach 20% or more." According to Fuel Finder, the optimal range for fuel economy sits between 15°C and 20°C, but once temperatures reach 32°C, engine performance deteriorates and overheating becomes a concern.
