My local city-owned electric utility held a public information meeting to talk about their future strategy. We have a big problem in Colorado Springs because we held onto an obsolete coal fired plant for too long, entirely for political reasons, and now our rates are higher than Boulder. That is pretty embarrassing. So we are scrambling around to try to catch up to 21st century electricity technology.
One possibility they mentioned was a pilot V2X program. Maybe it will happen or maybe they will be swamped by other more important problems, and maybe Nissan won't enable the feature (even though it is documented in the online owner's manual on the Nissan web site), but in any case, it leaves me with a question:
What sort of electrical setup do those 4000 or whatever it is houses in Japan have? I assume you need something with a CHAdeMO connector on it, and then something comparable to the inverter and isolation unit that comes with rooftop solar. What about the breakers and GFCIs that you have already put in place, what happens to them when the electricity is going in the backwards direction?
My suspicion is that it would be tough to set up a rate structure that would make this all worth doing on a daily basis, but it might be worth it if you could run your furnace from the car if there is a grid power failure in the winter. I am more interested in what the household wiring looks like.