The total costs to implement government-mandated safety measures, maintain facilities and decommission commercially operated nuclear power plants in Japan will reach around 13.46 trillion yen ($123 billion), a Kyodo News tally showed Wednesday.

The amount, which could balloon further and eventually lead to higher electricity fees, was calculated based on financial documents from 11 power companies that own 57 nuclear reactors at 19 plants, as well as interviews with the utilities.

Two years after the 2011 Fukushima nuclear crisis, the Japanese government introduced new safety standards which made measures against natural disasters and major accidents mandatory for restarting reactors.

The power companies have been given the option of either maintaining their idled nuclear power plants and restarting them once they had implemented the required safety measures, or decommissioning their plants. But it has become clear either choice required massive costs.

Of the total costs, 5.4 trillion yen was for safety measures implemented as of last month at 15 power plants they are trying to restart.

(File photo taken from a Kyodo News helicopter on May 30, 2019, shows the No. 3 (L) and No. 4 reactors at Kansai Electric Power Co.'s Takahama nuclear power plant in Fukui Prefecture, central Japan.)

Decommissioning costs for 17 reactors belonging to nine nuclear power plants, which were deemed too expensive to implement safety measures for, totaled around 849.2 billion yen.

As the estimated costs for decommissioning the No. 1 to No. 4 reactors at the Fukushima Daiichi nuclear power plant run by Tokyo Electric Power Company Holdings Inc. differ, they were not included in the figure.

Maintenance costs, which will not only apply to restarted plants in operation but also to idled ones and those in the process of being decommissioned, are required for 54 reactors at 17 plants.

Those under construction were excluded. In the six years from fiscal 2013, when the new regulations were introduced, they totaled around 7.2 trillion yen.

The costs include labor, repairs and others considered nuclear power plant expenses as shown in each company's annual securities report. But plant depreciation costs and a reserve for dismantling facilities were subtracted as they overlapped with some expenses for safety measures and decommissioning.

Maintenance fees will be required every year moving forward and are expected to continue to grow from the annual costs of around 1 trillion yen across the 11 utilities.

The total costs could further rise by several hundred billion yen as money needed to construct anti-terrorist facilities, also required under the new safety standards, was not included in the figures of some of the companies.

The majority of the 17 reactors at nine power plants slated for decommissioning are aging and they also include four at the Fukushima Daini complex, which local officials requested to be scrapped.

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