The cost of restarting Japan's nuclear power plants: ¥1.3 trillion and counting.

That is the amount power companies have committed so far on thousands of tons of reinforced concrete and steel, armies of workers, tsunami walls and seismic tests.

It has all been to meet tougher safety standards for the 48 reactors on coastlines throughout the earthquake-prone country. And also to convince regulators the defenses will withstand a quake and tsunami on an intensity of what struck the Tohoku region three years ago Tuesday, causing one of history's worst civil nuclear disasters and shutting down the nation's atomic plants.