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Comment by dboreham | Hacker News Reader

People posting claims about EV charging time should be required to also post the size of cable required. And the grid capacity needed to provide their fast charging at a typical 8-bay charging site.

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The grid capacity depends only on the number of charged cars, not on their charging speeds.

The latest high-power chargers made in China that achieve the 5-minute charge times have their own batteries for providing the charge power, so they take from the grid only the average power, not the peak power.

could a charging site have a buffer of fast charging batteries?

Yes, but have you ever seen 8 queues of cars, about 8-10 cars in each, at Sams Club or Costco buying gas? You'd need a awful lot of battery buffer to keep up with that kind of demand. At some point you'd deplete the batteries and be stuck with charging at whatever rate the grid connection could deliver.

With EVs, most of your charging should be done at home, with fast charging mostly just existing for trips.

I know not everyone can charge at home (especially if you live in an apartment), but the solution to that is pretty straightforward and a lot more convenient compared with trying to scale up fast charging to match petrol stations.

First, that exact situation simply doesn't have an equivalent in the EV world. Quite a lot of people should be able to charge elsewhere (at home, at work, on the street).

Second, wow, I live in Europe and I have never seen 64+ cars queueing at a single station. If I saw 15, I'd be wondering what the hell happened.

Lots of people (apartment dwellers) cannot charge at home. Charging at work or on the street is still a very uncommon option here (USA).

I’m an apartment dwelling EV owner, so I’m well aware of that, but even here, where high density housing is pretty common, at least 50% people could theoretically charge at home with no or minimal adjustments. And on top of that, workplace and street charging should follow EV adoption, it’s not like either EVs or the infrastructure are going to appear overnight.

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