Electric car ranges under scrutiny: Unraveling factors influencing distance in summer heat versus high-speed travels.
In a groundbreaking analysis of over three million trips, Geotab has found that driving speed has a much greater impact on the range of electric vehicles (EVs) than air conditioning use, even in high temperatures.
According to the data, an electric van with a 65 kWh battery, for instance, can cover around 143 miles at 50 mph and 86°F with air conditioning on. As speed increases, the range decreases significantly. At 60 mph, the range drops to 121 miles, 70 mph reduces it to 103 miles, and at 80 mph, range falls sharply to 88 miles.
The reason behind this trend is aerodynamic drag, which increases exponentially with speed. At higher speeds, it consumes significantly more energy than air conditioning would. For example, driving twice as fast results in four times the aerodynamic drag. This finding suggests that speed and its effect on aerodynamic drag are the dominant factors controlling EV range in high temperatures.
At lower speeds, heating or cooling demands have a more noticeable effect on range since aerodynamic drag is less significant. However, at typical highway speeds, slowing down by 10–15 mph can extend range by 20–30%, far more effectively than reducing air conditioning use alone. Additionally, strategies like cabin preconditioning (cooling the vehicle while still plugged in) can help offset AC energy use without impacting driving range.
Charlotte Argue, Senior Manager for Sustainability at Geotab, notes that drivers often hesitate to turn on the air conditioning in warm weather, but the greatest range losses are primarily due to high speeds. She also points out that modern electric vehicles have larger batteries, which allows them to cover most daily routes with a single charge, even in commercial use.
Range, whether in electric or internal combustion engine vehicles, is a dynamic value that depends on temperature, route profile, traffic, and driving style. However, when it comes to electric vehicles, particularly in high temperatures, slowing down is the most impactful way to preserve battery range.
In sedans, the range decreases by about 28% at higher speeds. For example, a sedan's range drops from around 446 kilometers at 80 km/h to 322 kilometers at 128 km/h.
In summary, while air conditioning in hot conditions does contribute to range reduction, speed and its effect on aerodynamic drag is the dominant factor controlling EV range in high temperatures. Reducing speed is therefore the most impactful way to preserve battery range in summer driving.
- The impact of driving speed on the range of electric vehicles (EVs) is significantly greater than air conditioning use, even in high temperatures, according to a study by Geotab.
- Driving at lower speeds can extend the range of electric vehicles by up to 30%, compared to reducing air conditioning use alone, according to the data provided by Geotab.
- In electric vans with a 65 kWh battery, the range decreases significantly as speed increases, from 143 miles at 50 mph to 88 miles at 80 mph, even with the air conditioning on.
- strategies like cabin preconditioning (cooling the vehicle while still plugged in) can help offset AC energy use without impacting driving range in electric vehicles (EVs).
