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Comment by Animats | Hacker News Reader

240 watts over a USB-C connector? What next, USB toasters and coffee pots?

You joke, but this is enough to make recharging an e-bike practical. E.g. https://amplerbikes.com/pages/nova

This is my dream. To reverse engineer my bikes charger and create an USB pd to take with me on a self-sustained trips.

That's only a single ampre at standard European mains voltage. It's still a lot of power for those tiny connectors and insulation, but an order of magnitude insufficient for those appliances.

I bet that cable gets plenty hot at 200+ watts.

USB-C is limited to 48 VDC. Above about 50V, electrical safety codes apply.

Yes, 240 watts is 5 ampres at that voltage - that's why I suspected that the cables get hot. I'm even surprised that a cable so thin is sufficiently insulated for 48 volts. I've seen 24 volt truck wiring arc out of dirty connectors.

You need a e-marked cable to get to 5A with any PD voltage, as a random crappy cable could get dangerously hot indeed. The limit is 3A and 20-21V otherwise.

You sure?

Those regulations go even higher.

https://en.wikipedia.org/wiki/Extra-low_voltage

The controlling standard is usually 62368, and the target is usually being a "Limited Power Source", which is 60V or less, and 100 VA max.

A full sized European electric kettle is about 2000 watts, but if you limit capacity to a single cup you can get acceptable performance on 200 watt. A USB-C coffee pot or kettle scaled to 0.2 liters (7oz) could work. Would be a great option for travel

Toasters are frequently only ~750W. That isn't an order of magnitude away from the capabilities of current USB-C.

I doubt they'll ever increase the voltage beyond the current 48V (I was actually shocked that they didn't stop at 24V) so toasters are forever away. But not an order of magnitude away!

I remember scoffing years ago at USB powered coffee warmers. Maybe the situation has changed.

The Ember cups could have used PD! But the cables would have been more expensive, as would have the power brick (and you would have had bad user experiences plugging into less powerful USB power supplies)

I mean my electric Fan and standing lamp are both powered by USB-C.

There are things that shouldn't be powered by USB-C. But there are plenty of sub 100W consumer electronics devices that really should be USB-C. I waited years before Panasonic released their lamdash shavers using USB-C.

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