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Comment by vhanda | Hacker News Reader

Not who you're asking.

I really don't see why we're still using A/C inside our houses / apartments. I understand that the transmission loss is lower when sending A/C, so it makes sense, but then nearly every device in my house has their own AC to DC converter. Just have one AC-DC converter per building.

I'd like the future to just be USB-C sockets in my house. We have USB-C PD 3.1 which supports up to 48v, I imagine that would be good for all devices.

There are probably safety reasons why this future might be difficult.

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That would have been a good argument to make a decade or two ago but these days switch-mode power supplies are very efficient, and GaN ones even more so.

I have a small mess of 12-ish volt computer/network equipment in the corner of my office and looked into running it all off of one $40 high-amp power supply to eliminate all the wall warts and bricks. By the time I figured out power distribution and termination, buck/boost converters for the things that aren't 12V, it all seemed like a lot of work compared to just spending a couple hours tidying up the cabling and hiding the wall warts.

You can live in the future now and install power outlets with USB-PD built right in, although a quick glance suggests they top out at 65W. Fine for phones and tablets, might not keep a gaming laptop charged while in use.

A lot of appliances need >1kw.

This requires higher voltage and robust connectors.

That level of DC is quite dangerous compared to AC for many reasons.

Also, unless you want to have 60lb extension cords the size of bratwurst, you need to go high voltage. High voltage DC is its own kind of devil, and is something I would not want in my household except in very isolated, self contained places.

High voltage, high current DC is on yet another level of mortal threat, able to do cool tricks like making extensions cords burn from one end to the other like cartoon dynamite fuses. Also, absolutely the best for accidental electrocution, severe burns and flash blindness, and setting otherwise fire resistant structures thoroughly aflame.

At USB voltages, one or two volts of drop is significant. You need very heavy cables, and for every voltage USB-PD allows you'd need another set of cables.

Also, some devices run directly on AC, or need more than USB can do, even with EPR. Since we already need AC for that, why add more wires when USB chargers are cheap and efficient and reliable these days?

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