In recognition of Japan's rapidly aging nuclear plants, Kansai Electric Power Co. has begun discussing the possibility of decommissioning the Mihama No. 1 and No. 2 reactors, now more than 40 years old, in Fukui Prefecture.

While Kepco officials insist no decision has been made, scrapping them instead of applying for a two-decade extension could set a precedent for other prefectures where older plants that went online in the 1970s and early 1980s, like the ill-fated Fukushima No. 1 plant, now face more stringent safety regulations, posing huge expenditures for any utility interested in keeping them.

The two Mihama reactors in question went into service in 1970 and 1972 and generate a combined 840,000 kw, a small amount compared with modern atomic units, which can generate over 1 million kw each.