I've been driving a Tesla model S for the past 8 years (I've had my current high-performance P85 model for 6 years). There is something that I have yet to understand, regarding range efficiency vs. speed. I have always thought (from my limited understanding of electric motor efficiency), that there is a direct, linear, correlation between speed and energy consumption (the higher the speed, the higher the consumption per unit of time, in a linear fashion). Does driving 30 miles at 75 mph really use up more energy than driving the same distance at 55 mph?
Am I wrong on the concept of that linear relationship? The reason for my post is when the range to the next supercharger becomes a concern, you get the warning "Decrease speed to make it to your destination". Reducing speed will obviously reduce consumption, but it will also take you longer to get there. So if you need 10 KWHr to drive 30 miles at 55 mph, does that mean you will use more KWHr if you are driving at 75 mph? Would consumption be the same only in a vacuum (theoretically), and is it wind resistance that reduces the range at higher speeds? Or is there another factor that would reduce efficiency at higher speeds?
This has always been a concern for me, as I drive a lot on road trips, and have always wondered if lower speeds equate to better range. I realize this is a question more related to the efficiency of electric motors, and would appreciate any input from those in the know, either from personal experience or from an electric engineering angle. And what are the opinions as to the optimal speed to drive an EV in order to get maximal efficiency (an therefore optimal range)?
Am I wrong on the concept of that linear relationship? The reason for my post is when the range to the next supercharger becomes a concern, you get the warning "Decrease speed to make it to your destination". Reducing speed will obviously reduce consumption, but it will also take you longer to get there. So if you need 10 KWHr to drive 30 miles at 55 mph, does that mean you will use more KWHr if you are driving at 75 mph? Would consumption be the same only in a vacuum (theoretically), and is it wind resistance that reduces the range at higher speeds? Or is there another factor that would reduce efficiency at higher speeds?
This has always been a concern for me, as I drive a lot on road trips, and have always wondered if lower speeds equate to better range. I realize this is a question more related to the efficiency of electric motors, and would appreciate any input from those in the know, either from personal experience or from an electric engineering angle. And what are the opinions as to the optimal speed to drive an EV in order to get maximal efficiency (an therefore optimal range)?
