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Comment by danans | Hacker News Reader

Expect these teardrop Porsche 911-esque designs with long slopes on the back to become more common in EVs since they minimize drag to help maximize range.

For even more extreme examples see the Aptera or the Light-Year.

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Those drop too quickly, the air separates near the top. It doesn't buy you anything. Compare to the first Honda Insight; that's about as perfectly aero as a practical car can be.

But I don't see that being a priority. They're selling well as-is.

> Those drop too quickly, the air separates near the top. It doesn't buy you anything.

Unless it's a complete fabrication, Light-Year claims that the design is relevant to aerodynamics:

https://lightyear.one/articles/lightyear-0-the-most-aerodyna...

That looks correct. I was referring to the 911, which has a steeper angle.

I hope the Aptera gets made. Being able to charge with 110v and get a decent amount of range overnight seems like a good thing, especially or renters who may not have access to a quick charger where they live.

Most current EVs can get a decent amount of range overnight on a standard household outlet.

Do you mean a dryer-type outlet? A regular plug would give cars 20 miles over 8 hours tops.

I got 50 to 60 miles of drivable range overnight on Level 1 last winter. Adding 12 kWh overnight can get you from Seattle to Everett and back, or to Kent and back.

Just make sure to drive an efficient vehicle, a Mercedes or Hummer EV ain't gonna do much with 12kWh.

I think 5mph is pretty typical on a standard 15 amp circuit (pulling 12 amps per code). That would get 40 miles of charge in 8 hours.

And if you hire an electrician to upgrade the outlet to 20 amps you can add another 1-2mph. This can be trivially easy or somewhat complicated, depending on what kind of wire is supplying the outlet. But even in the latter case it's usually less work than installing a Level 2 (240v) charger.

Cars are usually at home for quite a bit longer than 8 hours and since can charge close to 4 miles an hour. The small difference is important, since average mileage is about 30 miles a day. If you average charge more than you average drive you'll probably use fast chargers less often than you'd use a gas station.

Nope, 120V/15A. We get about 5 miles per hour, and the car is generally parked for ~14 hours, so about 70 miles of charge per night. Our car uses about 240 Wh/mi, and a standard US outlet can safely deliver maybe 1400 Wh per hour, so it pencils out.

EVs don’t need special plugs for most people.

This is interesting because in European 230V sockets a 2kW power is safe and well under rated maximum of ~3kW. So if you park your car at around 7pm and leave at 7am you get 24kWh charge from a simple standard socket. It could deliver another 12kWh, if you have a charger that can be configured to go higher and you know you won't overheat any cables or connections along the way.

Some houses have the red plug, a three phase plug which can do 11kW continuous, around 7kW sustained and very safe.

Yep, high voltage can be useful heh. The US has 240V sockets for things like dryers and ovens, they're just not as abundant. Prospective EV owners here seem to fret about not having one in the garage, but it's not necessary.

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