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by gambiting 1491 days ago
It just doesn't make any sense if you know anything about physics. Sun provides about 1kW of power per square meter.....at noon, at the equator, with no clouds.

Automotive solar panels like they use are about 20% efficient. Your average car roof is....let's be super forgiving and say 2sqm. So in the middle of the day, at the equator, you are generating about 400W of power.

The average EV battery is 50kWh. So you'd need 125 hours in full sun to recharge it fully. During a regular sunny day you'd get maybe.....2-3kWh back into your battery? So yeah, about enough to cover ~10 miles in a regular EV.

Sure it's better than nothing, but remember that this is in ideal conditions. In less than ideal conditions you are talking yeah, enough energy to cover a mile or two per day of charging. It's just silly.

4 comments

Bear in mind too in winter the days are shorter, sunlight is weaker, and you're using *aaaaaaall* of the electrical goodies.

Even down south here at 56°N there's about five hours of sunlight in winter and as you get further north it just gets shorter. That's about enough charge to get the length of a supermarket car park.

This illustrates how inefficient cars are for individual transportation. An eBike takes between 10 and 20 Wh per mile. Gas is so inexpensive and energy dense that we just got unware how ridiculous it is to drive by car even on short distances.
And the Aptera is a lot more efficient than a normal car. Glance at their home page and you'll see why. https://aptera.us/
eBikes are extremely slow. What's the point of them? Just ride a normal bike.
You seem to forget that bar exceptions (people working on the road all day), most passenger cars are staying parked 99% of the time and use for small errands.

The aptera is also built to provide up to 1000miles in its highest spec out of one complete charge.

Right and how long does it take to charge that 1000 mile range in an average British city? A full year?

And I'm not forgetting it - I'm just saying that the overall gain doesn't seem to be worth it. The cost of solar panels integrated into the car would pay for a lot of electricity from the grid instead.

Right, if you need to fully charge then plug it in. You'll do that after a road trip. But if you live somewhere sunny and typically drive 20 miles a day, you can keep it topped up by just parking in the sun.

Some will find this worthwhile, others won't. Apartment dwellers without convenient chargers might find it handy. The comment I replied to advocated doing your own energy production, and if that's what you care about, grid power doesn't really compete.

The aptera is still plugable and you would still benefit from the efficiency even in sorry sad UK...And I have seen nowhere anyone saying it was for everyone. It only have 2 seats and limited luggage capacity for a start, it won't replace a family van.

I live in Andalusia where decent sunlight is all year and I would love a similar thing with 4 seats. With only 2 I don't really see the advantage over using my motorbike which is much easier to park.

Luggage capacity isn't bad if you don't need much vertical space. It has that big flat area in the back.
The first poster is clearly talking about local power generation when they say roof, so a building, not the freaking vehicle.
I started by talking about solar collection on the roof of a building, which applies to any electric vehicle.

But Aptera actually has panels on the car. That would be useless on a Tesla, but the Aptera is far more aerodynamic and only has three wheels. They don't claim to fully recharge in a day, just to get enough extra range in a day to cover many people's typical driving needs.

I'm literally replying to a comment that is talking about solar panels on a car, did you reply to the wrong person maybe?
No, I replied to you because you felt the need to hammer on the misunderstanding in the comment you replied to. The horse, it's dead, look, it doesn't twitch when I beat upon it!

Both of you had the opportunity to not assume the first post was stupid but passed on it.

You're name making any sense. None.

This model of car has an option to charge from the sun, with solar panels on it. The misunderstanding is yours, and it is you beating a dead horse.