Japan will do the same thing that America does when they need more power. They'll fire up the COAL plants until it's safe to return to nuclear. For how long?? We don't know the extent of damage of the other nuclear plants. All news has been about the one plant.
Some natural gas could come into play, since liquid natural gas can be refined on the tanker, but again we don't know the extent of damage when it comes to piping natural gas to the places it's needed.
COAL! Look at the movement of BTU over the last couple of days. JRCC is still affordable, as well as some of the other mines.