Burning a gallon of gasoline generates about 125,000 BTU, or 36.63 kW-hr of heat. Let's do the numbers. GM advertises this car as getting 4 miles per kW-hr, which seems about right. And that's the very best you could do, with the sun shining directly down on the panel. In clear weather in subtropical latitudes, you'll get the equivalent of maybe 4 hours of direct sunlight per day.
Some people do charge their EVs with solar power.
I've seen the one at the South Coast Air Quality Management District in Diamond Bar, and one at the San Diego County government administration building . Depending on how much sunlight is available and how much EV charging goes on, the site may be either a net consumer or a net producer of electricity at any given time. The car draws very little power when stopped, as an electric motor does not idle like a gasoline engine. There's no clutch, so with the car in drive and the brake pressed to hold the car, the propulsion motor is stopped and draws no power. Also, the headlights, HVAC and other accessories may be on.