This is a short video that includes a rough equation for calculating what size system of solar panels will charge an EV. The example shown is for a Tesla Model 3 but an Aptera’s 100 watts/mile demands can be plugged into the formula.
Having admittedly just scanned through what all the video has to say, the biggest omission seems to be a failure to speak to seasonal variations. Average insolation per year tells you little about how much more than you know what to do with, you will generate mid summer versus the weeks or months long stretches when you may be generating virtually nothing mid winter.
My ground mount PV array in the American Pacific Northwest may generate 50kWh a day mid summer but then go weeks at a stretch never cresting over 10kWh (and often only 2 or 3) a day during the winter months.
The average only works if you are lucky enough to have a local utility that lets you effectively bank your summer surplus on the grid so that you can draw down those kWh credits during the winter. That is my good fortune so I currently provide about 60% of my driving kWh from my PV array. Again that’s a yearly value for the stand alone PV and would not be even close to true daily or even weekly for three or four months without the grid tie.
Even setting aside offsets from the Aptera’s built in PV, I will be able to provide (in the above mentioned round about way) 100% of what the Aptera would need so I am still eager to get mine.