Japan's uncertain nuclear energy outlook in 2012

(Photo credit: iStockphotos.com)

On New Year's Day, only six out of 54 nuclear power plants were operating in Japan, and they are due for routine maintenance before May. The Nuclear and Industrial Safety Agency (NISA) of the Ministry of Economy, Trade and Industry (METI) presented on 18 January a draft appraisal on the stress-test reports for the O-i #3 and #4 nuclear plants of Kansai Electric to the committee of experts, stating that the reports were "appropriate".

Following the Fukushima Daiichi accident, the government had set the stress-test as a pre-condition for restarting nuclear reactors after regular maintenance. The draft will be revised in February, taking into consideration comments presented at the meeting as well as advice expected from the International Atomic Energy Agency (IAEA) experts who visited Japan in January.

The finalised report will be sent to the Nuclear Safety Commission of the Cabinet Office for their review, and the final decision will be made by Prime Minister Yoshihiko Noda after consultation with heads of local governments. Fourteen stress-test reports have been submitted so far. However, this process would by no means be simple and straightforward, since nobody knows as yet if and when any reactor will be allowed to restart. This summer, Japan is to again face extremely hot issues of severe electric power supply and demand problems.

Meanwhile, the Japanese government last December declared that Fukushima Daiichi nuclear power plants had reached a state of cold shutdown and entered the second phase of containing the accident. Japan will have to walk a long and hard road of decontamination and decommissioning, solving a number of unknown and difficult challenges in terms of technological as well as socio-economic aspects. The government announced on 6 January a plan to amend the Nuclear Reactor Regulation Law to explicitly stipulate the life of nuclear plants to be 40 years in principle, making it imperative to review and restructure energy and environmental strategies accordingly.

Fukushima Daiichi goes into second phase

On 16 December 2011, Prime Minister Noda declared at a government nuclear emergency response meeting that the Fukushima Daiichi nuclear power station had reached a state of cold shutdown, coming to the end of the accident response phase.1

He stated that diversity and multiplicity of water injection systems are assured to keep the reactors sufficiently cool and that radiation at the plant boundary could be kept at low enough levels even in the event of "unforeseeable incidents". This declaration marked the transition from the first phase of stabilising nuclear reactors to the second phase of decommissioning them.

Following this, a joint team of the government and Tokyo Electric announced on 21 December a "mid- to long-term roadmap" on decommissioning the Fukushima Daiichi reactors. The process is divided into three phases. In phase 1, removal of spent fuel from storage pools will commence within two years. In phase 2, removal of damaged fuel or fuel debris (re-solidified fuel and its cladding tubes after meltdown) will start within 10 years. In phase 3, decommissioning the reactors and disposal of all radioactive wastes will be completed within 30 to 40 years. More specifically, the team plans to start removing spent fuel from the storage pool at the Fukushima Daiichi #4 unit within two years, and finish the fuel removal step in the second phase. Reprocessing and storage procedures for the fuel will also be determined in the second phase.

It is also necessary to decontaminate the nuclear reactor buildings, check and repair water leakage from the reactor vessels, and recharge water in the vessels to start removing fuel debris around 2021. Advanced robots must be developed to perform these procedures as they will have to be carried out under prohibitive high dose environments. The reactors will be decommissioned after 10-15 years when they are cleared of all fuel debris.

"We will proceed with the technology development by mustering all wisdom in the world and by the joint efforts of the government and the private sector," said Mr Goshi Hosono, State Minister in charge of nuclear disaster. Such a statement was prompted by the fact that the experience from the Three Mile Island (TMI) accident alone is insufficient because fuel canisters at Fukushima Daiichi did not stay within the reactor pressure vessels (RPV) as in the case of the TMI accident, but melted down and was partly leaked into the pressure containment vessels (PCV).

On 28 December, Minister Hosono proposed a plan to construct interim storage facilities for contaminated soil in Futaba-gun near Fukushima Daiichi power station to facilitate the radiation cleanup activities. Soil at Futaba had been exposed to 100 micro Sievert per hour (µSv/h) or more of radioactivity, making it difficult for inhabitants to return early to the area. The Japanese government's idea understandably invited intense anger and resistance from the local community. Prime Minister Noda visited the Fukushima prefecture on 8 January and asked for acceptance, but obtaining consent seems extremely difficult. Decontamination may not proceed as planned and the return of evacuees will be further delayed if the interim storage sites are not determined. A consensus with significant implications for the local people must be formed in order to get the green light for nuclear decontamination.

Life of nuclear reactors to be set at 40 or 60 years

At a press conference on 6 January, Minister Hosono outlined amendments to the Atomic Energy Basic Act and the Nuclear Reactor Regulation Law, which stipulate severe accident management conditions, drawing upon lessons from the Fukushima Daiichi accident. The government will set up a new "Nuclear Safety Agency" under the Ministry of the Environment this April as well. The gist of the amendments is as follows:

1. Impose a 40-year cap on the operational life of a nuclear power plant. Extension may be given in an extraordinary case, upon request by a power company, and if it poses no problem.
2. Introduce a "back-fit" scheme to make the existing nuclear plants comply with the latest standards.
3. Legislate for accident management, which is now a voluntary process at power companies, and clearly provide in the law that power companies are primarily responsible for taking safety measures.
4. Introduce a framework for an emergency measures in order to protect life and health of the public during a disaster including orders to stop operation of nuclear power stations.
5. Integrate safety regulations on nuclear power stations stipulated in the Electricity Business Act into the Nuclear Reactor Regulation Law.

The Nuclear Reactor Regulation Law already requires utility companies to appraise technical safety of 30-year-old nuclear stations in light of "anti-ageing measures". After that, the Nuclear and Industrial Safety Agency (NISA) will examine the safety of the nuclear stations every 10 years, while no limit is currently imposed on the operational life of nuclear reactors. The operational life will be stipulated in a law for the first time in Japan, and Minister Hosono emphasised at the press conference that "we will thoroughly apply the policy of no safety, no nuclear". Under the new legislation, an electric utility company may submit an application for extension of the operational life of a 40-year or older nuclear plant. The government may approve the extension as an exception after examining the utility's technological ability to evaluate long-term degradation and to ensure safety.

The extension is allowed only once for each reactor and the extension period must be specified on the application. Specific examination standards have yet to be developed, but a Cabinet Office official on 17 January disclosed a plan to limit the extension to a maximum of 20 years. This explanation has brought about another dispute among stakeholders, as the maximum life of a nuclear plant could reach 60 years, as had been discussed before the Fukushima Daiichi accident.

How to deal with replacement of ageing nuclear power stations

Four Japanese nuclear plants are now 40 years or older, with a total capacity of 1,657MW. Operation periods of 21 units including the above with 15,631MW in total capacity will exceed 30 years within 2012, accounting for 32 percent of the current generation capacity of 48,847MW for 54 nuclear plants. By 2030, 15 more units or 14,303MW will pass the 40-year mark, leaving only 18 units totalling 18,913MW of capacity or only 39 percent of current capacity. All nuclear units in Japan will be older than 40 years by 2050.

The Fukushima Daiichi accident has led us to undertake a fundamental reappraisal of the Basic Energy Plan. Those opposing nuclear energy are strongly pushing for denuclearisation, but the majority of the Japanese populace probably would think that practical options should inevitably include nuclear energy to sustain the Japanese economy. It is impractical or unacceptable for society to overkill the economy and bring down quality of life simply to press for a reduction or elimination of nuclear energy. Imposing a cap on the operational life of nuclear plants eventually calls for us to restart constructing new nuclear plants or at least replacing aged ones. It is going to be a heavy and difficult task to form a national consensus on when and how we should initiate this process.

Article republished with permission from the Institute of Energy Economics, Japan (IEEJ).