solar losses due to heat build up are a concern of mine. in my testing, the current can nearly be cut in half due to thermal buildup. will the aptera have any kind of solar cooling to keep the current at maximum? In the vehicle design I have been working on, the plan was to use passive cooling by creating a small pocket of space between the solar and the actual roof, with a simple adjustable louver system at the front of the vehicle and a vent at the rear. thanks so much.
The Aptera Forum
Good question and I am not sure.
I could share “other information “ that you may find useful but NOT your answer.😞
As you may know.... the solar array will also power an interior heat venting system for the vehicle itself, besides the Never Charge.
Understand Aptera is coming in on completing their Development vehicles soon, so spec should be available shortly.
The battery specs were ~ 0-120*F. The Dev vehicles would be tested with their final choice of batteries
Both my homes’ PV Solar Arrays were/are roof mounded and the brackets set them about 4-6” off the roof itself, so that did provide some passive cooling and the heat loss did not seem that bad. I am in solar zone 8 now and I am checking my production on my 7kWh system.... It is producing 6kWh per day on these partly cloudy, nearly 100*F summer days
I never clean my home PV solar panels and I am in an dry dusty desert
I would think most would clean there aptera frequently, for what that is worth on production 😉
Apetra’s website has their solar calculator.
I believe I read they had significant hrs of testing on the present Never Charge solar array on their simulation jig.
I assume all tested in sunny southern CA.
The decade old small solar array on their old 2e was mainly used for venting heat from those old 12 or so (?) prototypes
Just for reading... you may find this product interesting as to how they maintain the efficiency of the PV generation, with, tracking, passive cooling, self cleaning. Of course not for mobile use! It is $$$
Smartflower.com
I was going to investigate this but we have too many breezy days here, so it would be closing and reopening too frequently
The situation with solar on a vehicle that may be an issue is not the same as with a typical solar installation. typically there would be space for air to pass under the cells to allow for passive cooling. with a vehicle, there is no elevation between the solar and the roof, thus the heat build up. I will contact solar team Eindhoven and ask what they have done with their solar cars. seems almost necessary to allow for some type of cooling (to gain max efficiency). One of the men driving an ELF trike with a trailer I put together that has 600w of sun power cells on it has given me great feedback about this issue.
Einhoven doesn't use any passive cooling. They say
"When Stella's are at a standstill, they do not get any active cooling. They actually get quite hot! During driving, they are cooled by the wind, so no active cooling needed (at least not from our side)."
I wonder what kind of lifetime advantage to cell longevity and increased energy output could be had with simple passive cooling, or even better, a small fan to draw in cool air when there isn't enough wind to have a useful air exchange.
If, as Len mentioned, forced air cooling will be used to keep the cabin comfortable, doesn't that count as active cooling of the back sides of the solar cells?
@Harry Parker only if the cells are open to the cabin, which I am sure they are not since they need some sort of structure under them for support and to keep them from getting damaged by say, a 2x4 hitting the roof during loading into the car for example. The cells would need to have the least amount of insulation between them and the air circulation to have any noticeable effect on current loss prevention. They could however, be attached to one side of a semi-hollow honeycomb like structure that allows airflow, while keeping them safe from damage from inside and outside of the vehicle.