[PhantomPholly]

Even napkin math would tell you this is not much of an idea if you're hoping for a free charge. Supposing they put flexible panels on the roof, perhaps 2 square yards @10% efficiency (flexible are not as efficient). If you parked at the airport in Tucson for 10 days, you might get 1Kw * 4 hrs * .1 efficient = .4Kwh per day = 4Kwh total in 10 days. Not very much - and that assumes you can park in a place at an angle to improve the orientation of the panels to the sun.

However, to prevent battery bleed down on an extended trip leaving the car at the airport? Might be almost mandatory.

 

[brian_]

However, to prevent battery bleed down on an extended trip leaving the car at the airport? Might be almost mandatory.

True... and applicable to most vehicles, EV or not. Decades ago U-Haul rented travel trailers - built to their design and specification - and had each of them equipped with a small solar panel to keep the battery alive between uses. That's still a decent idea, especially with extensive electronics in modern cars causing battery run-down problems, and still about all that a vehicle-mounted panel is good for.

Well, there's one more: a panel-equipped vehicle can run a ventilation fan to the extent permitted by power available from the panel. This reduces interior overheating, and the solar panel output is nicely matched to demand due to solar heating of the vehicle interior.

 

[john61ct]

It is also critical for the millions of people that live off-grid in their vehicles for extended periods.

Admittedly not much demographic overlap with Tesla ownership. . .

 

[brian_]

It is also critical for the millions of people that live off-grid in their vehicles for extended periods.

Sure, if you have piles of rooftop space on a 5 to 10 ton vehicle, and ongoing power demand while parked, solar panels make a great deal of sense. RV installations are very common.

 

[PhantomPholly]

True... and applicable to most vehicles, EV or not. Decades ago U-Haul rented travel trailers - built to their design and specification - and had each of them equipped with a small solar panel to keep the battery alive between uses. That's still a decent idea, especially with extensive electronics in modern cars causing battery run-down problems, and still about all that a vehicle-mounted panel is good for.

Well, there's one more: a panel-equipped vehicle can run a ventilation fan to the extent permitted by power available from the panel. This reduces interior overheating, and the solar panel output is nicely matched to demand due to solar heating of the vehicle interior.

Yes, this is also true and I've often wondered why it isn't a standard option available for vehicles sold in the hotter climates. Fan runs most when the sun is up, pretty fool-proof (although they seem to be damned clever about creating better fools).


But as a "battery keeper" this seems like a no-brainer.