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Comment by sparkman55 | Hacker News Reader

Each element on an electric stove is roughly 2 kW. Let's say you have a 4-burner stove, and they're all on. That's 8kW of power.

Let's say we run your 'simplified' household at 48V (the highest voltage commonly used in boat/cabin DC systems). To run 8kW on 48V you need 167 Amps. For 167 Amps you need something like 2/0 wire. That's really thick and heavy cabling!

Can you imagine replacing all of the wiring in your walls with this stuff?

http://i1194.photobucket.com/albums/aa378/chance1525/Mobile%...

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That reminds me of a funny story: a friend was working on some servers in a big telco and saw two guys carrying something that looked like a heavy, thick pipe, and a big hammer. "Hey, what's that?" "Power cable for the UPS [one that kept the whole building up]" "And what's with the hammer?" "Well, we have to bend the cable..."

This is exactly the issue. To deliver the power needed at such low voltage, you need thick cables. And thick cables are expensive in materials and installation. Can you imagine a typical j-box or load center with, say, a dozen of these bad boys coming in and leaving?

Due to the size, the changes needed would not be confined to the electrical system -- you'd have to figure out a way to maintain structural strength and fire safety despite the large openings for cables.

It's possible to imagine houses wired with low-power DC and high-power AC (both), but it'll never happen in my lifetime, hence a general lack of enthusiasm.

Erm, you can series enough storage batteries to make double-ended DC at +-120V, which will actually work just fine with existing electric stoves / water heaters. Yes, there will be some new safety issues and it will take the electrical code a while to catch up for safe residential installation (hopefully they'll deprecate romex!), but these are not insurmountable.

No, I certainly can't imagine doing that. However, a person doesn't typically cook 12 hours a day. Instead, they cook in bursts, so it makes sense to put a bank of batteries in or near the stove (firewalled of course), and trickle-charge them with normal cables.

No, it doesn't make sense to do that. The nice, efficient system we have is far superior to having everyone invest in expensive, fragile batteries everywhere and never be able to cook more than 30 minutes without recharging for 12 hours.

Now you've got me dreaming about my battery-powered hair dryer. And my battery-powered electric tea kettle, microwave, and espresso machine.

Not to mention the battery-powered table saw and air compressor in my garage.

The "Battery Bank" appliance, with no user serviceable parts inside, and consuming valuable real estate in my kitchen? I'll pay the extra few bucks per decade to not have that in my kitchen.

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