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Comment by axiolite | Hacker News Reader

> I cannot reasonably run lengths of 110v extension cords down the block to charge a car overnight, and acquiring my own house with a garage is dramatically more expensive

You don't need a garage, just some sort of reserved parking space... There are plenty of weatherproof electrical boxes. It costs a bit of money to have a trench from your home to your car parking area, but far less than buying a house.

And that "110v extension cord" can supply 240V with just a change of connectors on either end (e.g.: 6-30p) allowing charging twice as fast.

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In most places you can't just put a trench and an electrical box through public spaces. I'd also worry about someone stealing electricity from me. Double the voltage is hopefully ok on the extension cord- just don't be tempted to run higher current. Extension cords are also not recommended for permanent usage.

> You don't need a garage, just some sort of reserved parking space

I don't think the OP was worried about people who have the ability to dig a trench and install underground wiring to a reserved spot in a "car parking area". I suppose it's not technically having a garage but it sure feels like it in spirit.

A 6-30 NEMA connector still only supplies 30 amps. 30A x 240V = 7200W. Which is under 10hp. You're still looking at an awfully slow charge.

For a road trip it's slow, for overnight it's plenty fast. A big battery is 100 kWh. Assuming one only uses the middle, from 20 to 80%, that's 60 kWh, which would charge in 8 hours and 20 minutes at that rate. The vast majority of folks spend at least that long in one location every day. How often do you tend to arrive home at 10 p.m. and leave before 6:30 a.m.?

7.2kW is about 30 mph charging speed on regular cars. So you'll gain around 300 miles of range over 10 hours. That's basically a full charge.

My bet is probably 90% (99%?) of home charging is done at 7.2kW or less. 7.2 kW is in the higher end, not "awfully slow". Myself I often charge at 3.6 kW.

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