Did you know that only around 20 percent of what you spend on gas turns into movement? That is literally like burning $80 each time you spend $100 on fuel. How efficient is a Tesla compared to that? Jason Fenske, from the Engineering Explained YouTube channel, went through the trouble to make the calculations and discovered they are very efficient.
To do so, he had to calculate the amount of energy his Tesla Model 3 Performance has to spend to beat aerodynamic drag and rolling resistance. And he further than anyone would probably have the patience to make the most precise calculations possible.
Since we do not want to ruin your chance to watch the video with spoilers, you’ll have to check it to discover how efficient his Tesla is. We just wonder how a Tesla compares to other EVs and if a Long-Range would not be even more efficient than the Performance. Fenske, please give it a thought about making these other comparisons in the future, if you may.
Video Description Via Engineering Explained On YouTube:
How efficient are Teslas? Now I’m not talking about MPG ratings here, anyone can look up efficiency ratings. The 2018 Model 3 Performance is rated at 116 mpg combined equivalent; what I’m curious about, is how much energy that starts in the battery, actually makes it to the wheels to push the car forward? What percentage of the battery power goes towards useful work? This turned out to be quite challenging, but the results are fascinating; enjoy the watch!
For aerodynamic drag, air density was determined using an air density calculator plugging in ambient conditions (temperature, pressure, humidity) for when and where the testing occurred. This results in an air density of 0.00245183 slug/ft^3 (whatever a slug is). The drag coefficient was determined using the frontal area of the Tesla Model S and relating to the size and shape of the Tesla Model 3, estimated at 23.69 square feet (2.2 m^2). Actual velocity was determined using GPS, not the onboard displayed speed; a correction factor (approximately 0.97 derived from 72.7 mph = displayed 75 mph) is applied to aerodynamic drag to ensure displayed speed matches actual tested speed. Tesla provides drag coefficient at 0.23. The total weight of the vehicle includes my weight, for a total of 4,225 lbs. A coefficient of rolling resistance of 0.01 is used. The very best “green tires” of recent history are around 0.006 to 0.007. AllTyretests.com claims a Crr of 0.0096 for the PS4S tire, so we’re assuming 0.01. According to Continental via tirereview.com, “there is no longer any difference between summer and winter tyres in terms of rolling resistance” hence I’ve used 0.01 for all Crr calculations.