gnu- that is nonsense.
Directing flow through high power cables (which came from inland plants to the SW of Tokyo) through areas damaged by earthquake and tsunami took crews and heavy equipment several days- as it would if similar conditions obtained in the U. S. or Canada.

Power grids service large areas and needs of all must be considered.
Eastern Canada is connected to the American grid. See map of U. S. grid with connections to Canada-
http://www.npr.org/templates/story.php?storyId=110997398

A power grid map of Japan is also on the internet.