What driving speed helps electric cars save battery the most?
Practical tests show that the speed of an electric car directly affects the battery power, which means it affects the distance an electric car can travel after each charge. So what speed helps the car save the most battery?
The range of an electric car, or how far it can travel on a single charge, doesn't just depend on the battery capacity. In fact, many different factors can affect this figure.
For example, extreme heat or cold outside temperatures can make a battery less efficient. The size, type of tires, weight of the vehicle, number of passengers and cargo also contribute to energy consumption. Even seemingly small details like wheel size or aerodynamic shape can make a significant difference.
Like gasoline-powered cars, electric cars have to contend with physical forces as they move – from wind resistance, rolling resistance to gravity when climbing hills. Speed, in particular, is the biggest “battery drain.” The faster you drive, the more air resistance there is, meaning the car has to use more energy to maintain speed. This reduces range dramatically.
To achieve the ideal driving range, you need not only a large battery capacity, but also a steady speed, ideal road conditions, and limited energy-wasting factors. Even the electric car with the best operating range according to the US Environmental Protection Agency (EPA) in 2025 cannot avoid these natural laws of physics.
What speed will help electric cars save the most battery?
To answer this question, the MagazineCar and Driverconducted a real-world test with three models, including two electric cars, the Lucid Air sedan and the Kia EV9 SUV, and a gasoline-powered Subaru Forester as a control. The goal was to test how speed affects the distance an electric car can travel on a single charge.
The EVs tested had varying EPA-estimated driving ranges, depending on the trim level, but the results showed a clear trend: the higher the speed, the more range was lost.
For example, at around 35 mph (56 km/h), the Lucid Air sedan offers a claimed range of around 480 miles. But at around 55 mph (88 km/h), that number drops to 370 miles, a loss of over 100 miles just because it’s going faster. At around 75 mph (121 km/h), the range drops to around 290 miles, a 23% loss.
In particular, when tested at a speed of about 153 km/h, the remaining range decreased by another 24%, to only about 355 km, less than half of the speed at about 56 km/h. Meanwhile, the Kia EV9 SUV with a less aerodynamic design had an even more serious decline.
This test clearly showed that the faster the electric vehicle runs, the more energy it consumes, and the distance it can travel will be significantly reduced. This is an important factor that users need to consider if they want to optimize the operating range of each trip, especially on long routes.