Geotab Analysis Shows How Temperature & Speed Impact EV Range

Geotab has introduced an interactive analysis for fleets. The tool helps fleet managers discover what causes range loss which can increase confidence for EV drivers and fleet managers. It provides guidance on selecting the right vehicle for the job and the conditions at hand. 

The analysis takes into account the vehicle’s day-to-day range, and that true operational efficiency is influenced by numerous factors including:

• Road conditions
• Weather
• Topography
• Speed
• Tire inflation
• Driving style

Effect of Speed and Temperature on Range

The interactive analysis by Geotab shows how an electric vehicle’s (EV’s) maximum range can change depending on climate and driving behavior.

The chart below shows that the optimal temperature to maximize range is 68F for the sedan (solid orange line) and the light cargo van (dotted orange line).

But the ideal speed where the range is maximized changes with the temperature. If a sedan’s range of 68F is maximized at approximately 19 mph, whereas at 32F the optimal speed is doubled to 37 mph.

"This is the result of a tradeoff between the amount of energy required to overcome drag and the energy needed to keep the vehicle cabin at a comfortable temperature," Geotab's analysis explains. "Faster speeds will get you to your destination more quickly, meaning less total energy spent on HVAC, which is good for range. However, faster speeds also means more energy is needed to overcome drag, which is bad for range."

According to Geotab, efficiency peaks at even slower speeds because the force of drag is stronger on a van. At an ideal 68F temperature, the most efficient speed is 16 mph. At freezing temperatures, the optimal speed is approximately 25 mph.

"The reality is for most fleet applications, today’s EVs can complete their trips on a single charge regardless of speed or temperature. For the longer routes, having an understanding of seasonal temperatures and road speeds can provide guidance on trip planning, and whether a charging stop should be part of the itinerary," Geotab states in the analysis.