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Comment by imaginenore | Hacker News Reader

But then you should read on why we use high voltage AC for transmission.

Hint: the resistance losses are ~ amperage squared.

No, I get it. Tri-phase is name of the game in the old transmission model. But that model is long overdue for a rebuild. Remember the 2003 blackout? Managing and synchronizing grids is more than a full time job, and this contest seems to promote a bandaid.

Anyhow, my point is that in the localized-power game (say solar cells, fuel cells, etc) it's all DC already, and it's all right near where it needs to go. Fuel cells are near cars, and solar panels are right next to what they need to power: TVs, etc.

Complications are airconditioners and big appliances, except those things are already massive enough that it makes sense to install an inverter next to each one.

That DC might as well be AC since it is not as stable as you'd like. Consider this, you have a DC source 5-15V and want to run a usb gadget from it. You still need a regulator between the wall plug and the device. Why not make it compatible with AC grid so your kitchen appliances don't need their own inverters each?

It's a lot easier to build a converter that steps down from 15V with a shared ground, than from 170V that requires isolation.

Of course, house distribution wouldn't be done with 15V, the lowest it'd probably be is 48V.

For localized solar, it's not a problem. If your solar is on top of your house, then the transmission losses aren't the problem.

Now, I think (as mentioned above) if you have the inverter for the whole house and some sort of UPS at the feed, it becomes an easier problem.

Minor voltage drops can still be a problem for optimal tracking on MPPT charge controllers.

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