Electric car

At night, the house will power an electric car. This will, according to this post, not require new power plants, because it will use available capacity at night.

AC/DC

Have both AC and DC outlets. Most of what I use these days either is DC or could be. But I get AC power and convert it using a transformer that awkwardly sticks out of the wall. Let's all agree on a standard and rewire to DC, so I don't waste electricity. Also, I could use solar panels and feed directly off a battery. Here's a post on Treehugger covering this well.