A significant percentage of the energy in household use (by my unscientific and guess-heavy research) goes into low-voltage items. Computers, charging phones and batteries and media players and the like. Pretty much anything with a wall-wart is using a good sized chunk of it's power to convert from 120VAC to 6-12VDC (or whatever voltage is required. And, many of those things have batteries that they're charging. They don't need always-on power, and they don't need 120VAC.
So here's what I envision...
A parallel wiring setup that distributes low-voltage DC power throughout a home could power a lot electronic equipment more efficiently and cheaply. Instead of transformers all over the place, you could have one large one that provided low-voltage power more efficiently. Even better, you could hook this system up to an on-site generator. Solar and wind are more effective at generating low voltage DC than at generating AC power, so it would be the ideal way to start getting some of the power load off the grid. And the generator I'd like to see is the WindBelt.
I'm obsessed with this thing. From what I've seen, it's scalable, durable and has a minimum of moving parts. They're smaller than a turbine and cheaper than solar panels. You could mount them on your roof line and it wouldn't change the appearance of your house very much at all.
Of course there are issues with this idea. Electronics manufacturers would have to standardize on voltages and connectors, but the fact that they don't is stupid anyway. Homes would need to be rewired, but I don't see that as being substantially more complex than adding cable outlets. And, of course, someone needs to build the technology and market it. But this could be a big first step. If it worked, I can see many people thinking "What else can I move to this system?" We'd probably see an upsurge in demand for things that could run low-voltage, like LED lighting.
Would you buy a system like this if it were available? How would you improve this idea?