Costs for anti-terrorism and other safety measures to restart idle reactors in the aftermath of the 2011 Fukushima nuclear disaster now stand at more than 6 trillion yen ($41 billion), an Asahi Shimbun survey found.

The outlays incurred by the nation’s 11 utilities have significantly undermined the cost advantage of nuclear power generation, experts say.

Some sites face situations that are peculiar to them alone, which ramped up the overall total.

The Asahi Shimbun has maintained an annual check on outlays for safety measures since 2013. Revised regulatory standards drawn up by the nation’s nuclear watchdog after the 2011 disaster obliged the 11 utilities to take steps at their facilities against earthquakes and tsunami and guard against terrorist attacks.

The results of an Asahi questionnaire in July showed that total costs borne by utilities reached 6.15 trillion yen.

The eye-watering sum was in part due to increased expenditures by Chugoku Electric Power Co. and Hokkaido Electric Power Co. compared with the previous year.

Chugoku Electric is planning to restart the No. 2 reactor at its Shimane nuclear power plant in Matsue in December. In addition, the No. 3 reactor now under construction at the facility is undergoing screening by the Nuclear Regulation Authority. For these reasons, the utility’s safety costs increased by 220 billion yen to 900 billion from a year earlier.

Hokkaido Electric logged an increase of 39.6 billion yen from the previous year by investing 261.8 billion yen to erect a coastal levee to block tsunami at its Tomari nuclear plant in Hokkaido.

TOUGHER CRITERIA

To date, 12 reactors at six nuclear power plants operated by Kansai Electric Power Co., Shikoku Electric Power Co. and Kyushu Electric Power Co. have been brought back online.

Based on responses to the Asahi Shimbun survey, safety costs per reactor for the three operators are estimated at around 200 billion yen, which includes spending for the compulsory introduction of anti-terrorism equipment.

The costs of enhanced security at reactors now moving toward resuming operations following NRA screening are expected to be far higher.

For example, putting a reactor into operation at the Shimane plant entails an outlay of 300 billion yen. The figure excludes additional expenses mandated by the NRA for anti-terrorism measures.

Tohoku Electric Power Co. intends to shell out 710 billion yen to reactivate the No. 2 reactor at its Onagawa nuclear power plant in Miyagi Prefecture around November.

Tohoku Electric explained that forecasts of stronger earthquake and tsunami are pushing up costs for reactor restarts compared with earlier outlays.

All six reactivated plants are projected to be able to withstand maximum tsunami heights of under 10 meters. The strongest possible temblor is expected to churn less than 1,000 gals--a measure of tremor acceleration--at these facilities.

In sharp contrast, it has been assumed that the Onagawa nuclear power plant could be hit by tsunami up to 23.1 meters in height, with the strongest quake estimated at 1,000 gals. This led to building an anti-wave levee standing 29 meters above sea level.

The Shimane nuclear power plant also has a levee standing 15 meters above sea level to protect the premises from tsunami with a maximum potential height of 11.9 meters and the strongest possible tremor of 820 gals.

“Differences in countermeasures against tsunami and earthquakes can have a grave impact on total spending,” noted Satoshi Sato, a former engineer at a reactor manufacturer, referring to the staggering 100 billion yen or more required to construct an anti-tsunami levee.

Sato pointed out that enhancing the seismic resistance of piping and equipment is apt to be costly because the procedure is so complicated.

Several other reactors currently undergoing inspection for potential restarts are expected to face severe earthquakes and tsunami in the future.

Sato stressed that safety measures for some nuclear power plants “may become particularly expensive as well from now on.”

The ballooning costs could lessen the competitiveness of nuclear power generation.

The government’s 2021 cost prediction for each power source considered nuclear electricity plants that had applied to the NRA for screening. Safety measure expenses per reactor were estimated at around 200 billion yen, a sum that was utilized to determine the cost of building a new nuclear power plant.

(This article was written by Keitaro Fukuchi and Fumi Yada.)