This is a problem that--well, I'm not going to say it's solved, but it's certainly addressed in an ongoing way. In the NE you have a lot of dinky little power plants burning coal and whatever else, but if you look at the NW there's huge hydroelectric. Hydro has to be located where it made sense to build dams; this hasn't always matched up with the needs of the grid. Long distance transmission is thus an ongoing reality. Power from Bonneville goes out to Montana today; it's not hard to imagine the reverse.