On September 6, an M6.7 inland earthquake struck the eastern Iburi district of Hokkaido, registering an intensity of 7 (the largest on the Japanese seismic intensity scale) at Atsuma Town and causing massive damage. Due to the immediate shutdown of Hokkaido Electric Power Company’s Tomatoatsuma Thermal Power Plant (3 units with a total of 1650MW), the AC current frequency was disturbed, leading to blackouts over the whole of Hokkaido.
The maximum seismic acceleration at Tomari Nuclear Power Plant (PWR, 3 units with a total of 2070MW) itself was small, at 7 Gal, but external power was lost for nine-and-a-half hours due to the blackout. The external power loss was resolved in nine-and-a-half hours because power from a hydroelectric power plant that resumed generation soon after the earthquake was sent to Tomari NPP on a priority basis. (Power was also similarly distributed to thermal plants other than the damaged Tomatoatsuma Thermal Power Plant, which was unable to resume generation, to provide them with the power necessary for resumption of power generation.)
Tomari NPP has been shut down for over seven years and the nuclear fuel has been transferred to spent fuel pools. When the earthquake occurred, six emergency diesel generators were started up to provide the pools with cooling water.
Although the construction of Chugoku Electric Power Company’s Shimane Nuclear Power Plant Unit 3 (ABWR, 1373MW) was almost complete when the Fukushima Nuclear Power Station accident occurred, work to bring the reactor into operation was halted. On August 10, aiming to start up the reactor, Chugoku Electric Power Company applied to the Nuclear Regulation Authority (NRA) for a review of compliance with the new safety regulations. Depending on how the review progresses, Shimane NPP Unit 3 could become the first newly constructed nuclear reactor to start up since the accident.
However, when the NRA’s first review meeting opened on September 4, it was found that the length of the active fault that was supposed to have been reexamined after the preceding review for Unit 2 was not reflected in the application, and it was therefore thrown out with the comment, “This cannot be reviewed as it is.” It was agreed that the review would begin after submission of corrections, but it has also been reported that the NRA was flabbergasted by Chugoku Electric Power Company’s attitude.
On August 2, TEPCO Holdings CEO Tomoaki Kobayakawa visited and held discussions with Mayor Masahiro Sakurai of Kashiwazaki City, Niigata Prefecture. In reply to the mayor’s demand for a decommissioning plan for Kashiwazaki-Kariwa Nuclear Power Station (KKNPS) Units 1-5 (all BWR, 1100MW), CEO Kobayakawa replied that TEPCO would reply by June 2019. In December 2017, the Nuclear Regulation Authority recognized completion of compliance under the new safety regulations with regard to restarts for KKNPS Units 6 and 7 (both ABWR, 1356MW), but TEPCO Holdings has not yet applied for reviews of compliance for Units 1-5.
After the discussions, however, CEO Kobayakawa stated to reporters his assessment that the option of aiming for the restart of all seven reactors was still open.
On August 22, Hitachi announced that its subsidiary in the UK, Horizon Nuclear Power would be the ‘owner/engineer’ for the overall project management in the construction of a two-reactor nuclear power plant in the UK. In 2016, Horizon Nuclear Power formed a primary subcontractors’ consortium named Menter Newydd consisting of the Hitachi subsidiary Hitachi Nuclear Energy Europe, Ltd., Bechtel Management Company Limited, and JGC Corporation (UK) Limited, concluding an engineering, procurement and construction (EPC) contract. This consortium was dissolved in mid-August. Bechtel signed a new contract to provide project management, while JGC and Hitachi Nuclear Energy Europe also signed separate contracts with Horizon, continuing in the roles they have performed thus far, but leaving the burden of risk solely in the hands of Horizon Nuclear Power.
While Hitachi has reduced its controlling share of Horizon Nuclear Power from 100% to less than 50% as a condition of groundbreaking, reactions to its overtures to financial institutions and others for funds have apparently been less than encouraging.
The four companies TEPCO Holdings, Chubu Electric Power Company, Hitachi and Toshiba exchanged a memorandum aimed at partnership in August. The former two are BWR owners and the latter two are BWR makers. Tohoku, Hokuriku and Chugoku Electric Power Companies are also all BWR owners, as is the Japan Atomic Power Company, which own one unit, but none of these other companies are involved in the partnership.
TEPCO Holdings and Chubu Electric Power Company have set up a joint venture, JERA, in a move toward integration of their thermal power businesses. However, this is not proceeding well. Even more difficulties are expected with the nuclear power businesses.
At the Higashidori Nuclear Power Station, TEPCO Holdings has Unit 1 (ABWR, 1385MW) under construction and a similar Unit 2 planned, but progress on both of these is suspended. While the company is calling for the establishment of a joint venture to restart the project, there has been no response from any other power company. There has also been no response to Hitachi’s call for funding for the construction of a nuclear power plant in the UK (see above).
The four companies say they will push forward with the partnership by firstly setting up an engineering company that will handle maintenance and management services, but it does not look as if it will be all that easy.
The Japan Atomic Energy Commission’s (JAEC) specialist panel on the system of compensation for nuclear damage finalized its draft report on August 6 and called for public comments up to September 10. The report is due to be finalized soon.
While deliberations continued for three years, the miserable result is that the draft simply recommends that the status quo be maintained. The majority of opinions in the panel favored a raising of the current 120 billion yen compensatory ceiling, but the draft report mentions only a deferment, going only so far as to say, “continued prudent consideration is necessary.” The reasoning is as follows. The ability of the private insurance market to take on the risk is at its limit, and with changes in the competitive environment associated with reform of the electrical power system the site risk evaluations due to the safety measures taken by each of the companies have not yet been determined.