Photo/IllutrationFrom left: The No. 5, No. 6 and No. 7 reactors at Tokyo Electric Power Co.’s Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture (Asahi Shimbun file photo)

  • Photo/Illustraion

Soaring costs borne by operators of nuclear power plants to safeguard their facilities against natural disasters and terrorist attacks suggest the government is wrong in its longstanding contention that nuclear power is the nation's cheapest energy source.

A study by The Asahi Shimbun found that the overall estimate for the cost of safety measures by 11 operators stood at 5.074 trillion yen ($48.32 billion) as of July. The operators include those whose nuclear facilities are still under construction.

The combined figure for the 11 companies represents an increase of about 660 billion yen from a year earlier.

The Asahi Shimbun has tallied total estimated safety costs by nuclear plant operators since 2013.

As of January 2013, the combined total was 998.2 billion yen.

New safety regulations implemented after the 2011 Fukushima nuclear disaster obliged power companies to equip their facilities with additional safeguard measures to prevent a severe accident triggered by a powerful earthquake, tsunami, fire, terrorist attack and other emergencies.

The Fukushima disaster was triggered by the Great East Japan Earthquake, which generated towering tsunami that knocked out cooling systems at the Fukushima No. 1 nuclear power plant operated by Tokyo Electric Power Co., setting off a triple meltdown.

The new regulations went into effect in 2013.

TEPCO’s estimated cost to implement safeguard measures doubled to 969 billion yen in the latest study due to steps to counter liquefaction and terrorist strikes at its Kashiwazaki-Kariwa plant's No. 6 and No. 7 reactors in Niigata Prefecture.

Kansai Electric Power Co. reported an additional 130.8 billion yen as the cost of building an emergency facility to respond to a terrorist attack on its Oi nuclear plant's No. 3 and No. 4 reactors in Fukui Prefecture.

In the survey, The Asahi Shimbun for the first time asked power companies about their most recent estimates for countermeasures against terrorism and the previous estimate when they applied for certification of their anti-terror facilities by the government’s Nuclear Regulation Authority.

The responses showed that anti-terror measures are proving to be two times to five times more expensive than the companies initially envisaged.

Kyushu Electric Power Co. replied that such steps for the No. 1 and No. 2 reactors at its Sendai nuclear plant in Kagoshima Prefecture grew five-fold from 43 billion yen to 220 billion yen.

Kansai Electric Power Co. said it plans to spend 125.7 billion yen on anti-terror measures for the No. 3 and No. 4 reactors at its Takahama plant in Fukui Prefecture, up from 69.1 billion yen.

In the case of Shikoku Electric Power Co., the utility said measures to safeguard the No. 3 reactor at its Ikata nuclear plant in Ehime Prefecture from a terror attack surged from 32 billion yen to 55 billion yen.

Shikoku Electric said the increase is due to a change in the design and construction method following the NRA’s safety examination.

Of the 11 companies surveyed, six did not include costs for terrorism countermeasures in their estimates for safeguard mechanisms, which means that overall costs for safety measures, including those against terrorism, can only grow.

Nine reactors at five nuclear facilities are now back online after clearing the more stringent standards set by the NRA.

The safety cost for each of those reactors ranged from 130 billion yen to 230 billion yen.

It appears likely that plans by Chugoku Electric Power Co., Tohoku Electric Power Co. and Japan Atomic Power Co. to restart reactors will cost each of the operators more than 300 billion yen per reactor in safety measures, if the cost of implementing terrorism countermeasures is added.

With the ballooning safety costs, the government’s argument that nuclear energy is cheaper than hydro power and coal is increasingly in doubt.

In 2015, a government study put the cost to generate 1 kilowatt-hour of energy for hydro power at 11 yen, coal-fired thermal power at 12.9 yen and nuclear power at 10.3 yen or more.

The government study estimated the cost for safety measures per nuclear reactor at about 100 billion yen.

The power generation cost for a reactor will rise 0.6 yen for an increase of every 100 billion yen that will be set aside for safeguard measures.

(This article was written by Toshio Kawada and Keitaro Fukuchi.)