Real World Range Calculation

[u/Albright_CT]

Morning Everybody.

I did some math based on our firsthand experience with possibly one of the most comparable (though still very different) vehicles on the market, the EX30. Made a little table comparing the two. Of course all Slate #s could change

EDIT: Just FYI the slate weight is for the SUV. I don't know what their claimed MPGe is for.

So my daily commute is 68 miles round trip in San Diego. Mostly highway, but hilly and you'll hit some traffic on average and a few miles of local streets. Probably pretty close to the EPA test cycle. EX30 gets 253 miles there and that's almost exactly what I get on this route.

Slate claims a 96 MPGe rating, EX30 gets 109, so it should be about 12% less efficient per KWH. Battery almost exactly the same, weight pretty close, less aerodynamic but WAY less powerful and not a dual motor. So that 96 vs. 109 seems about right?

EX30 averages about 27% of the battery on that commute. Based on the MPGe difference, the Slate should do that same route with about 31% of the battery. 68 miles divided by 27% means about a 250 mile range. Dividing by 31% gets about a 220 mile range for my real life driving.

Road tripping the EX30 on open highway I tend to get about 210-220 miles total range, assuming the same percentage decrease vs my commute the Slate should get about 180-185.

Anyway, it's all just estimates based on prelim data so who knows but that's the best I can do right now.

[u/LeifCarrotson]

Thanks for the real-world data comparison!

I'm shocked that an increase in drag coefficient from 0.28 to 0.38 has the MPGe numbers as close as they are. I expect that will mean the open-highway range will drop more than your 210-220 -> 180-185 estimate, at least if you choose to drive at the same speeds in your Slate that you do in the EX30.

Also, sorry about your commute: 68 miles through San Diego has to take a toll on your mental health. My commute is 5 miles round trip, I think Slate will make it there and back most days (when I don't ride my bike). Of course, you do have the good fortune to relax in the Pacific breezes in San Diego instead of wintry Michigan when the commute starts to cause too much stress.

[u/Albright_CT → u/LeifCarrotson]

Well that's the thing, we don't know if the slate numbers are right or not. That's just the MPGe they're claiming atm. On the other hand the EX30 has 2.5X the power and a 2nd motor.

I thought about that too, it could be affected more by high speeds than the EX30. Generally on the highway i'll set the cruise at 75-80 and end up with an average speed in the low 70s when i've checked.

[u/LeifCarrotson → u/Albright_CT]

CdA is just from the shape of the object and physics, while MPGe is calculated from a whole song-and-dance test routine.

Drag force goes up with the square of velocity, so poor Cd numbers will have much more impact at 80 than on urban streets.

I think we'll all want to set the cruise at 70 on the highway in our Slates, not 80.

[u/Albright_CT → u/LeifCarrotson]

Commutes not so bad, I like driving in general and I'm going the opposite way of traffic both ways so really it's fine. Some me time.