What would happen if the two working reactors at the Oi power plant — Japan's only reactors brought back online since the Fukushima meltdowns last year — are shut down because of a suspected active fault under their critical equipment?

According to Kansai Electric Power Co., the Kansai region would suffer severe electricity shortages this winter because demand is projected to far exceed the utility's capacity to generate power through other means.

Kepco estimates that the peak demand this February will be 25.37 million kw, while the firm now has a maximum supply capacity of 26.42 million kw — including the Oi reactors.