Whether by the traditional lighter connection, by modern USB ports or wireless trays, charging your phone during a car ride can be very convenient. But do you spend more fuel?
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24/07/2026
by
News to Minutes
Load your phone while moving by car can be useful, especially when travel is a little longer or when using the mobile phone to display the navigation application, for example – thus preserving the load for when needed.
But in the case of combustion vehicles, will the shipment increase fuel consumption? The direct answer is yes. When feeding the device with the electric power of the car, is demanding that the alternator transform more engine mechanical energy into electric energy. Thus, the thruster will have to generate more mechanical energy, consuming more gasoline or diesel.
But the impact on general consumption is practically innocuous, much less than one percent of the total – even because low amounts of energy are used – at most, of a few dozen watts in the fast chargers. In a liter of gasoline, there is energy for about 9,000 watts/hour (9 kWh), while a liter of diesel has about 10,000 watts/hour (10 kWh) of energy. These are approximate values as they vary to slightly more or less in different sources.
Hypothetical scenario
Considering the numbers above, let us imagine a 300 km journey at an average speed of 100 km/ h which takes about three hours. Over time, we will always charge the phone to a power of 45 watts, which translates into expenditure of 0,135 kWh.
At the same time, the vehicle with 100 hp of power consumes on average 5.9 litres of fuel every 100 km traveled, which means – on this trip – a total of 17,7 litres (equivalent to 159,3 kWh gasoline energy and 177 kWh diesel).
The 0.135 kWh of the load is equivalent to about 15 milliliters of gasoline and 0,085 percent of total energy consumed. For diesel, it would be 13.5 milliliters, or 0.076 percent. The impact is therefore practically imperceptible to the portfolio.