Benchmarking Tesla Regenerative Braking

So I took my 2019 Tesla Model 3 Standard Range to a local benchmark hill. Configured to regenerate to a stop, I started at 70 mph and tracked the speed and altitude change:

• speed light blue - shows the GPS recorded speed descending the hill to 0 mph.
• altitude purple - shows the altitude of the car at each GPS recorded point.
• the only change was to turn off cruise control and Tesla coast to a stop.

As shown, the Tesla handles regeneration very nicely in a way that ordinary ICE cars and our previous Prius failed All the other cars were flashing their brake lights to keep their speed in check. Even in "B" mode, our Prius continued to accelerate and we had to touch the brake pedal. In contrast, the Tesla modulated the regeneration for a near constant deceleration and a safe stop.

Bob Wilson

 

A few metrics:

• 3,800 lbs measured by CAT scale
• 70 mph initial speed
• 55 ft altitude loss
• 29 seconds

Bob Wilson

 

GPS provides the X, Y, and Z metrics. So I use what was measured. BTW, GPS is on the 3d or 4th generation: https://en.wikipedia.org/wiki/GPS_satellite_blocks

Bob Wilson

 

Converting to standard units:

• 1724 kg
• 31.3 m/sec
• 16.8 m
• 29 seconds

Use these formula:

• 836,399 J = 0.5 * 1724 * (31.3 * 31.3) - change in kinetic energy
• 283,839 J = 9.8 * 1724 * 16.8 - change in potential energy
• 1,120,238 J
• 38,629 W = 1,120,238 / 29

Bob Wilson

 

I use car benchmarking software, Speedometer, on my iPhone. There are sets of car tuning and benchmarking apps available for smart phones. My survey found Speedometer fully meets my requirements and integrates well with Google Earth and Google Map.

Bob Wilson