Comment by Grim-444 | Hacker News Reader

Comment by Grim-444 | Hacker News Reader

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"can charge itself 40 miles a day in optimal conditions." <- I believe this is the "basic math" that you were asked to run.

Using random numbers from Google for a Tesla 3 for an example, it has a 50kWh battery and 305 miles of range. That's 164Wh per mile. 40 miles would require 6,560Wh.

Assuming you leave the car in perfect sunlight for a full 8 hours every day, and there's no cloud, and you get 100% sunlight for the entire 8 hours, then you'd need enough panels to produce 6560Wh / 8hr or 820W.

I could probably barely fit 300W-400W worth of panels on top of my vehicle, and that's with covering the hood, trunk, roof, everything.

So even in the MOST IDEAL possible scenario, where you have your car in perfect sunlight for 8 hours a day, you're not even half way to producing 40 miles per day.

The aptera has 750W of solar panels, so you're pretty close.

It also has about 40% less Cd, half the frontal area, much less powerful motors nd a fraction of the weight. Which is how you get from 8 hours of sunlight to 5.

Real world it's probbably more like 20-30mi

The most likely reason it won't become common is it's legally a motorcycle to get the weight down to something sensible (or has no legal category in some areas) because cars are a regulatory captured nightmare and we're literally not even allowed to have a sane sized vehicle.

The lightyear and sion are much closer to vaporware and their marketing departments are doing the concept a great disservice, but they have over a kW of panels and you could reasonably expect them to be mostly self charging if your commute is short or it's just for errands.

Your error was in presuming the same weight and drag coefficient as the Tesla. The Aptera is both much lighter and has a far lower drag coefficient. That's where the extra range comes from despite the relative lack of surface area.

Do you have a wh/km to backup your claim?

The apteta isn’t the subject of this article though. The aptera is legally not even a car, as it’s a 3 wheeler. It’s a pretty extreme vehicle. Very cool, but quite extreme. The subject of the article, is trying to be a normal 5 door car. So comparing it to the state of the art in normal cars makes sense. The claims with this car are aptera performance (40 miles a day) but with normal car form. How is that possible? That’s why people are suspicious.

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