TOKYO -- Japan's electric utilities are spending significantly more than what they calculated about two years ago on enhancing the safety of their nuclear power stations under tighter security regulations.
Nine regional utilities and Japan Atomic Power, a company majority owned by utilities, have asked the country's safety watchdog, the Nuclear Regulation Authority, to carry out stress tests on 20 of their reactors.
In a survey by The Nikkei, the 10 companies revealed they have spent a little over 2.4 trillion yen ($20 billion) on safety programs combined, up about 200 billion yen from June and roughly 2.8 times their aggregate estimate in January 2013.
Chubu Electric Power earlier estimated that the safety work at its Hamaoka plant in Shizuoka Prefecture would require some 300 billion yen. But it now says the cost is poised to rise to the upper 300 billion yen range as it needs an additional year to complete the work, a change it announced at the end of October.
Tohoku Electric Power in late September more than doubled its estimate for the Onagawa and Higashidori plants -- in Miyagi and Aomori prefectures -- to over 300 billion yen. The upward revision partly reflects higher costs for building sea walls.
The tally is certain to keep rising. Many nuclear plants are still at the beginning stage of their safety reviews and may need additional anti-earthquake and other safety features if deemed necessary by the authority.
In addition, most utilities have yet to set aside costs for measures to address the risk of terrorist attack as required under the stricter safety standards introduced after the 2011 meltdowns at the Fukushima Daiichi plant.