Here is my analysis of Apteras solar charging. I'm still working on it but this is almost complete. I'm copying some of my stuff that i posted over on the AOC discord:
I went through all the copper connects on the solar roof. If they are all connected like i suspect they are, then that means they split up the solar roof into two groupings. the blue circles are the unusual part of the copper connects where i believe the wires from the 2 groups are put into the body. There are 30 cells in the hood, 20 in the dash, 56 on the roof, and 82 cells on the hatch, with 6 on the chevrons. That's a total of 188 as they indicated the chevrons might not make it to production, 194 with the chevrons. On the picture of the solar mule it had 7 rectangles. I think they might be solar charging DC-DC converters. 1 for the hood, 1 for the dash, 2 for the roof. That leads me to believe the solar hatch will be broken up into 3 groups. That would be 3 groups of 27-29 cells which is similar to the roof (if the roof really is broken up into 2 groups.) The more grouping of solar panels there are, the more efficient it is at charging when one panel, or even a portion of one panel is shaded. Using home solar as an example, if 10 panels are using 1 AC inverter, when one panel is in the shade it drops the charging efficiency of all the panels by more than 10%.
Best guess is they are Maxeon Gen 3, 3.72 watt cells with 24.3% cell efficiency, and 82.51% fill factor. Max 0.632 volts, 5.89 amps. 188 3.72 watt cells give you the 700 watts of solar that Aptera says it will have. That would be 111.6 watts hood, 74.4 watts dash, 208.32 watts roof, and 305.04 watts hatch. Base aptera would be 76 cells at 282.72 watts. 106 cells at 394 watts with only hood option. 158 cells at 587.76 watts with just the hatch option. And 188 cells at 700 watts for the full solar package. These are unique in that they can be bent and are very durable.
https://youtu.be/ZKJBMiiCXus
https://youtu.be/CgEYfB_Bc5s
Aptera says in ideal conditions you can gain 40 miles per day with the full solar package. At 100 wh/mi, that's 4 kwh per day of solar charging. At 21.27 watts per day per cell. Base solar would generate 1617 watts per day for 16.1 miles. Hood option would generate 2255 watts for 22.5 miles per day. Hatch option would generate 3361 watts per day for 33.6 miles. Full solar would generate 4000 watts for 40 miles per day. This lines up with the stated 16/22/34/40 miles that Aptera states. But these are ideal numbers.
The math checks out as far as how much energy they say the solar panels will produce if the cars efficiency is 100 wh/mi. Per the NREL peak solar hours map, most of America gets greater than 5.72 peak solar hours per day in the summer. Using this peak solar hours calculator:
https://footprinthero.com/peak-sun-hours-calculator 5.72 hours on a 700 watt panel laying flat on the ground will give you exactly 4kwh of solar power per day. That would be 40 miles at 100 wh/mi. At Carlsbad California in July you would average 6.93 peak solar hours per day for 48.5 solar miles of range. In December you would only average 3 hours for 21 miles. You would average 5.3 hours for the year for 37.1 miles per day, or 1,354.15 kwh for the year and 13,541 miles of solar range per year. Of course the solar panels on the Aptera aren't flat but at different angles. So some would be more efficient or less depending on the angle, and which cardinal direction you park the car.
The National average cost per kwh of residential electricity is 18 cents, and 30 cents in California. The total 700 watts of solar on the car would save you $245 a year on grid electricity at the national average, or $409 a year in California from solar charging.
The $300 111.6 watt solar hood cost $2.68 per watt. The $600 305.04 watt hatch costs $1.96 per watt.
The $900 hood and hatch solar package saves $148 a year in electricity at the national average, or $247 a year in California. The break even cost at the national average is 6 years, in California you would break even at just 3.6 years. After you reach the break even period, the solar would be generating cost savings for you every year, year after year. Not everything is about is about payback cost though. Just like you don't expect a car to pay for itself, or how you buy things for aesthetic reasons. You don't have to buy the solar package. But if you did it has other benefits like off grid charging where you can't plug in, camping, and reduced co2 emissions from charging, and improved range when driving.
The following is the average peak daily amount of solar energy per day. The different solar panels are adjusted for angle and cardinal direction when parked. This gives you a rough idea of what you could expect, and you can use your own fudge factor to lower it 10-20% or however clouds your conditions are, and how much shade your parking spot gets. You can use the link above to find out the peak solar hours for your area.
Aptera system efficiency:
How efficient is the Aptera if you factor in solar?
Motormatchup estimates the 41kwh fwd Aptera gets 103wh/mi at 60 mph with 200lbs extra weight, 0.25kw accesory drain, 70 degrees F, and 500 feet above sea level
https://www.motormatchup.com/efficie...1978846a96b74e . At 60mph The Aptera would gain 4.7 wh/mi from base solar. Thats 4.7 wh every minute, every mile. The base solar aptera has 282 watts of solar, so your net efficiency becomes 98.28 wh/mi. The 41 kwh pack then has an effective range of 417 miles, gaining 19 miles from solar. It would take 6.95 driving hours between charging.
At 60mph with full solar you gain 11.6 wh/mi from solar. Your net efficiency becomes 91.3 wh/mi, your effective range becomes 448 miles, for an added 50 miles of range from solar. That would be 7.46 hours of driving time.
At 65mph it would use 114 wh/mi. Full solar would make it net 103.23 wh/mi, gaining 10.76 wh a mile. Range would be 397 miles at 41 kwh. Gaining 37 miles of range. That would be 6.1 hours of driving.
At 70mph it would use 126 wh/mi. Full solar would make it 116 wh/mi, gaining 10 wh/mi. Range would be 353 miles at 41 kwh. Gaining 28 miles of range. That would be 5.04 hours of driving.
Note: These efficiency figures are for driving during peak sun hours. If you are driving longer than the peak solar hours available in a single day, then the maximum added range per day will be limited to the total hours of useful solar in that day.
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