Japan’s Nuclear Regulation Authority (NRA) on 4 July approved the restart of the Japan Atomic Power Co’s (JAPC’s) Tokai 2 in Ibaraki Prefecture.
Tokai 2 is the third boiling water reactor (BWR) be approved for restart under the stricter safety rules following Tokyo Electric Power Company’s (Tepco’s) Kashiwazaki-Kariwa 6&7.
However, Tokai 2 is the first nuclear plant directly affected by the March 2011 earthquake and tsunami disaster to clear NRA screening. Further steps are required before it can resume operations. During the earthquake, the plant suffered an emergency automatic shutdown of its reactor and was cut off from its external power source. Then it was hit by a 5.4m tsunami, which incapacitated one of its three emergency power generators. However, the other two remained intact enabling the reactor to cool down several days after the disaster.
Tokai 2 still needs to clear two more screenings by regulators before November, when it will be 40 years old. If it fails, it could face decommissioning. Ibaraki Governor Kazuhiko Oigawa told reporters he intends to “closely monitor" the remaining reviews and called on the NRA “to conduct strict examinations”.
The more stringent safety rules introduced after the Fukushima disaster in principle prohibit the operation of nuclear reactors beyond 40 years, but an additional 20 years is possible if the appropriate safety upgrades are made and it passes the required reviews. So far, three pressurised water reactors (PWRs) have been approved for extended operation under the revised regulations: Takahama 1&2 and Mihama 3, all owned and operated by Kansai Electric Power Company.
Operation of Tokai 2 is not expected before March 2021, when construction to increase safety measures is scheduled to be completed. The restart plan also needs to be approved by local municipalities. Local residents have protested against restart of the unit. The plant’s evacuation plan covers 960,000 residents, the largest number of potential evacuees for a nuclear plant in Japan due to its location near a metropolitan area. It has yet to be completed.
JAPC filed for a safety screening to restart Tokai 2 in May 2014. The company predicts a potential tsunami as high as 17.1m and expects JPY180bn ($1.63bn) will be needed to construct levees and improve power sources, among other safety measures. None of JAPC’s reactors has been online since the 2011 quake. Given its financial problems, NRA has asked the utility to show how it will finance the safety measures. Tepco and Tohoku Electric Power Co, which had been receiving electricity from the plant when it was in operation, have offered to financially support the company. JAPC has already decided to decommission Tokai 1 as well as Tsuruga 1 in Fukui prefecture. The restart of Tsuruga 2 is in doubt after a panel of experts concluded the unit sits on an active fault line. However, JAPC still plans to apply for safety checks in order to restart it.
Continued operation for Ohi 3&4
Also on 4 July, the Kanazawa Branch of the Nagoya High Court ruled that Kansai Electric Power Co’s Ohi 3&4 in Fukui Prefecture need not suspend operations, overturning a district court ruling in favour of 200 residents who said the plant is vulnerable to major earthquakes and other disasters. The court said the reactors do not threaten the personal rights of those living nearby and that Kansai Electric has not underestimated the size of a potential earthquake in the area.
The two units resumed operation in March and May, respectively, after clearing new safety standards in May 2017. The reactors had been idle since going offline in September 2013 for regular safety inspections. Their operations were previously halted in March and July of 2011, respectively, for inspection and restarted in July 2012 after clearing provisional safety standards.
So far nine reactors have cleared NRA inspections confirming they meet the new regulatory safety standards and have resumed operation. These are Kyushu's Sendai 1&2 and Genkai 3 &4; Shikoku's Ikata 3; and Kansai's Takahama 3&4 and Ohi 3&4. Another 16 reactors have applied to restart.
Hope for Higashidori construction
Tepco is also planning to resume preparations to build the Higashidori NPP in Aomori Prefecture saying it will carry out a geological survey at the site from the second half of fiscal 2018 to fiscal 2020. “In restarting the Higashidori plant project, we will proceed with the geological survey so that we can build a safer and more technologically advanced plant,” Tepco President Tomoaki Kobayakawa said at a 29 June news conference.
Under Tepco’s current plan, the Higashidori plant will have two advanced boiling water reactors with a total output of 2.77GWe. Construction of Higashidori 1 began in January 2011 but stopped following the Fukushima disaster. Under Tepco’s reconstruction plan the Higashidori plant will be a key facility for the realignment and integration of its nuclear power generation business. Tepco wants to jointly operate the plant under a company that would be set up in fiscal 2020 with Chubu Electric Power Co, Kansai Electric, JAPC and nuclear plant manufacturers. However, those companies are cautious because the increase in demand for electricity has levelled off, and the costs for building nuclear plants and reinforcing older reactors under new safety standards are rising. Tepco said it hopes the utilities would decide around 2021 whether to join the project by taking into account the results of the geological survey.
New energy commitment
Under Japan’s new (fifth) basic energy plan, approved by the cabinet on 3 July, nuclear will remain a key energy source, accounting for 20-22% of the electricity generation up to 2030, with 22%-24% coming from renewable energy sources, while coal's share will be reduced to 26%, LNG's to 27% and oil's to just 3%. The government revises its energy plan about every three years, based on the Basic Energy Policy Law enacted in June 2002. The latest plan, like its predecessors, recognises the necessity of energy security for Japan, which is poor in fossil fuel resources. The policy includes commitments to "clean energy" initiatives but places emphasis on ensuring stable and secure energy supplies. It aims to reduce Japan's carbon dioxide emissions by 26% by 2030, compared with 2013 levels, and by 80% by 2050. It also aims to raise energy self-sufficiency to about 24% by 2030, compared with just 8% in 2016.