Good luck with that average "math"!Solar on your rooftop will not be even 10% of what's required to charge your car.
Let's run some numbers.
Assume 100 square meters of panels.
The panels generate 250W/m^2 at best, so let's say they generate an average of 100 over 8 hours a day.
100 * 8 * 100 * / 1000 = 80 kw-hrs.
A Tesla's battery pack holds 90 kw-hrs.
And the Tesla battery pack needs above 24 VdC to get a current charging amperage high enough to get your 80 Kwhrs in an 8 hour time span
Did you do your "let`s run some numbers math" using the OCV ratings...sure looks like it