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3nwf248 | 3 years ago

A 1 square meter solar panel generates 200W (when aimed perfectly at the sun). Since the car's top is a flat surface (as opposed to tilted towards the sun), that's cos(30) * 200W, or 173W. A typical compact car (Honda Civic) has a surface area of about 8 square meters if it were a perfect rectangle.

That's 8 * 173 = 1.384 kW, or 1.86 horsepower under wildly optimistic circumstances.

I call bullshit.

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keithnz|3 years ago

I'm pretty skeptical, and details are thin, but this is what they say in their FAQ... "Even though the longest range Aptera can drive for about 1,000 miles between charge, the reality is that most of our driving is 30 miles or less. For Aptera, 30 miles consumes about 3 kWh of electricity. Now, let’s say your commute is 15 miles each way, let’s assume it’s dark when you’re driving to and from work. While parked at the office on a sunny day, your Aptera could put back in about 4.4 kWh which is far more than what you’ll use that day. You’ll arrive home with more charge than when you left with. That’s how it works, it’s as simple as that."

jseutter|3 years ago

The prototype of their vehicle had about 700 watts of solar and provided about 40 miles/day of range. If the panels get roughly 6 hours of full insolation per day they're using about 100wh/mile. It's impressive, but only about 2.5 times more efficient than a Nissan Leaf, and still within the realm of possibility.

That same amount of solar on a Tesla would only give about 8 miles of range per day.

Rich Rebuilds has an interview/test with them. One of the people from the company mentioned that you have more aerodynamic drag on a bicycle than you do driving their vehicle.

For reference: https://www.youtube.com/watch?v=I-KdsjVQhu0

moralestapia|3 years ago

Something's off but I'm not an expert,

A Tesla Model S Long Range has a 95kWh battery, following the logic you present (which makes sense, btw) that energy is equivalent to a 127hp motor working for an hour. A Tesla definitely has more power than this, and it can definitely run for more than hour, so there's something else obviously missing (is regen braking THAT good?).

That aside, your 1.34kW should be enough to charge a big battery like this one in about two weeks, since that Tesla gets about 400 miles of range and Apteras are supposedly much more efficient, I think one should be fine if you expect to drive no more than 20-30 miles per day.

I believe them.

mwint|3 years ago

It doesn’t run at 127hp for an hour, you’d be going stupid fast.

My Nissan Leaf (which is decidedly more brick-shaped than a Tesla) cruises at 50mph at something like 10-15hp, or less than 12kW.

It takes surprisingly small amounts of power to maintain cruise speed on level ground.

(Obviously cruise power scales with the cube(?) of speed, so it’s not like 10x power gets you 10x speed)

crooked-v|3 years ago

> so there's something else obviously missing

Take a look at the shape of the car. Pretty much the entire thing is designed around minimizing drag.

namlem|3 years ago

Assuming the equivalent of 6 hours of sunlight at 173W to account for the lower output in morning and evening, that's about 8.4kWh per day. To go 30 miles would require an efficiency of nearly 3 miles per kWh. That's very ambitious, though not impossible. We'll see how they perform when deliveries actually being I guess.

mwint|3 years ago

My Leaf regularly gets 4.1-4.5mi/kWh.