Thursday, April 07, 2011
Fukushima transmission lines and substation
click image to enlarge
Daini was powered by midnight by the Fukushima substation. Why do we think that all six transmission circuits to Daiichi failed?
[4 circuits on the Okuma Lines (275kv) to units 1+2 and 3+4 and 2 circuits on the Futaba Line (500kv) to units 5+6. The Yonomori Line is not connected.]
Three towers would need to fail for a "station blackout".
Farther north, there were towers damaged or destroyed in the lowland swept by the tsunami, but they were in the path of the tsunami, close to the coast, and there were not many.