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Comment by wklauss | Hacker News Reader

I have long wanted to fully switch to DC in my life and would love to see common appliances designed for a DC world. It's a shame that the opportunity to discuss this is lost in this post because of the pedantic tone of the author.

Phrases like "I think it was a bit presumptuous for the architect to assume I wanted a kitchen with my apartment and make me pay for it" or "I don’t want to live with red hot heating elements and razor sharp knives. That sounds like a torture chamber" are ridiculous, even if you really try hard to see them as an attempt of making a joke. The continuous references about how many books he has and reads also threw me off.

The best part, so far, is the first Discus comment at the bottom.

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Joey Hess seems to live a much saner life, while also living on battery (and solar, I assume): https://joeyh.name/blog/entry/notes_for_a_caretaker/

joeyh++ And with a much better attitude too. Living off the grid certainly helped him come up with some innovative ways to use Git (e.g. git-annex).

Just what practical options are currently available? With roof-mounted solar panels becoming commonplace (at least where I live) it seems like 12V DC is a practical target, but it irks me that it gets converted to AC before being reconverted back to DC by a wall wart a few meters away.

80V DC might work, but 12V DC means the wires would be far too thick to be practical.

In the past you needed AC for the ability to have transformers. These days you can do that in other ways. But you still need a high voltage, meaning you still need that wall wart.

Well, 12V is really wasteful. Placing an inverter in the loop is probably cheaper and more efficient than routing 12V electricity though one's house.

That's the problem, there are not many (some fridges designed to be operated from car plugs, camping gear, things like that) and often is just an appliance that has a converter inside, so it is as inefficient as you'd expect. Not sure if there's a way to design stoves, fridges, ovens and washing machines powerful enough just using DC, though.

For stoves/ovens, just up it to 240V DC. They're just big resistors and will work basically the same (although mechanical power switches will wear out quicker, and now that I think more, triac-based ones may not turn off at all).

Things could get really interesting if say the EU started incorporating a requirement for things that should essentially run fine on DC to compatible with DC. Universal power supplies (computers, phone chargers, etc) and brushless motors (washing machines) should really only require tweaks of their control circuits. AC motors (fridges/dryers/air conditioners) and microwaves wouldn't be an easy change. They'd either need a local converter or for demand to ramp up for explicit DC versions.

Standby power supplies (the thing that powers the IR receiver and power button while your TV is "off") wouldn't function as-is, since the common method is to use a capacitor+zener across the power line. But changing that to a rectifier + small switcher doesn't seem terribly onerous.

>I have long wanted to fully switch to DC in my life and would love to see common appliances designed for a DC world.

Modern HE washers and dryers along with many other appliances already are in some sense. They have their own high efficiency power conversion built in to drive the motors at variable speeds. Powering current-gen stuff requires two redundant conversion steps, but the conversions don't lose too much.

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