New confidence seen at Sendai City30 June 1999
The 32nd annual meeting of the Japan Atomic Information Forum was held in Sendai City. This city is in the Tohoku district where many nuclear facilities are situated and is also the headquarters of the Tohoku Electric Power Co, which, in December 1998, started construction of Higashidori Unit 1, the first plant in Japan to be built on a new site in ten years. by JOHN NEDDERMAN
The pace of nuclear plant construction in Asia is accelerating. In addition to Higashidori, during 1998 work started on Ulchin 5 and 6 in South Korea, and Qinshan Phase III-1 in China. In 1999 another 6 units are expected to begin construction. These are Shika 2 (1358 MWe ABWR) and Hamaoka 5 (1380 MWe ABWR) in Japan, Lianyungang 1 (1060 MWe VVER) in China, Tarapur 3 and 4 (500 MWe PHWRs) in India and Lungmen 1 (1350 MWe ABWR) in Taiwan.
Looking further ahead, Japan has proposed building another 20 units before 2010 and according to Hiroshi Araki, President of Tokyo Electric Power Co, this target is “not impossible”. In his presentation, Young-Sik Jang, President and ceo of Korea Electric Power Corp, said KEPCO will have 28 nuclear power plants in operation by 2015 as electricity demand is once again growing by 10% per year despite the recent economic crisis. Today KEPCO has 14 units in operation and eight units are currently under construction, including the two 1000 MWe units at Shinpo in North Korea. Yaozhong Min, Assistant President of CNNC reported on the situation in China. All the projects initiated in the Ninth Five-Year Plan (8 units totalling 6600 MWe) are going ahead as planned and the Tenth Five-Year Plan is now being developed which is expected to include further nuclear plants. Taiwan, of course, is scheduled to build a second unit at Lungmen.
Araki also said that Japan has, for a number of years, produced one third of its electricity from nuclear plants and this has saved the equivalent of 70 million kilolitres of oil. Countermeasures are being taken for ageing and a policy of constant renewal has been adopted (for example, last year TEPCO replaced the core shroud on one of its BWR units) and a recent report indicates that a 60 year plant life is possible. The programme for using MOX fuel in LWRs is back on course, the storage of HLW and LLW at Rokkasho is well established and the first spent fuel has been shipped to the spent fuel holding pools at JNFL’s reprocessing plant in Rokkasho.
The main theme of this year’s conference was “Can Nuclear Energy Save the Earth?” Perhaps the best that can be hoped for is a reduction in the CO2 emissions from electrical generation which may help Japan to meet its COP3 commitment. As Hiroko Sumita, a lawyer, remarked, the pro-nuclear lobby should be prudent about using the global warming issue to promote nuclear power as the public is likely to think this is an excuse to build nuclear plants that the government and industry wish to build for other reasons.
The session on “Civilisation and Energy Security” was intended to show the global nature of energy supplies and how individual countries strive for energy security. Judith Kipper, Director of the Middle East Forum, US Council on Foreign Relations, gave a talk on the situation in the Middle East oil producing countries. Essentially, political instability has increased and economically these countries are suffering from the loss of oil revenues and over-dependence on oil production.
At present, the United States gets only 5% of its imported oil from the Persian Gulf but Japan gets most of its oil from this area and, in future, the Gulf will principally be an exporter to Asia.
Japan issues a Long-Term Program for Nuclear Research and Development at roughly five year intervals. As the last one was in June 1994, another one can be expected soon and this was the subject of a panel discussion which centred around the need for a plan and the ways the plans are written. Japan is probably the only non-socialist country to issue such five year plans. The voluminous reports are prepared by bureaucrats in “bureaucratic language” which, according to Soichiro Tahara, a journalist well-known for his outspoken criticisms, is designed to prevent the public from understanding the contents. Most panelists had reservations about the plans and felt that the time had come to change to an energy policy preferably covering the whole of Asia.
Japan has recently passed freedom of information legislation similar to that of the United States. One session was devoted to information disclosure and communications with the public and the keynote speaker, Isamu Sasaya, described how JNC (Japan Nuclear Cycle Development Institute) was preparing to comply with the regulations. In the case of the design and construction of the Monju fast reactor, 35 000 pages of information had been prepared. Even so, 30% of the information had not been disclosed to protect third parties (copyrights of suppliers etc). In 1988 Japan signed the Physical Protection agreement which requires signatories to take steps to protect the movements of special nuclear materials. In the discussion it was suggested that this agreement was being used as an excuse to avoid disclosure of information such as the movements of MOX fuel.
PUBLIC MEETING PLACE
This session was followed by a meeting with the public. These meetings started five years ago and the halls are always packed. Although there is not much meeting of minds, the meetings obviously serve a useful purpose in bringing the public and the nuclear industry face to face.
Yasumasa Togo, President of JNC gave the keynote speech on “Monju and its future and Plutonium Recycling”. It is now nearly three and a half years since the sodium leak occurred at Monju. Investigations into the cause were completed a long time ago. Proposals to modify parts of the plant have been developed but, as yet, cannot be implemented because they require a revision to the plant licence and this cannot be done without the agreement of local people. Once this has been obtained, it will take about two years to make and test the modifications, followed by a slow power escalation programme. After obtaining experience in operating a sodium cooled plant, Monju will be used to develop technologies for future fast reactor designs and high burn up fuel. At a later stage, the reactor will be used for investigating the burning of transuranic nuclides and transmuting or stabilising long lived fission products.
Although technically Monju is shutdown, it is, in fact, in the shut down operating mode which requires sodium to be circulated through 2 loops. This costs about ¥20 million/day ($160 000/day) including the salaries of the staff. JNC has a budget for Monju which should cover all costs but the utilities will help by seconding one third of the staff required for the project.
In February 1998, a Special Committee on Fast Breeder Reactors was set up to review fast reactor research and development. Hiroko Sumita, a lawyer and at one time Public Prosecutor in Tokyo, was asked to serve on the committee. As a lay person with no preconceived ideas about nuclear energy, she described how she came to the conclusion that, for Japan, nuclear energy was essential and fast reactor research should continue.
Japan has decided to continue the fast reactor programme despite the termination of similar programmes in other countries. As Katsuya Tomono, Executive Vice President of TEPCO, put it, Japan is dependent on the Middle East for 80% of its energy and so must make its own decisions and pursue the fast reactor. It is necessary to think 50 to 100 years ahead and renewable sources of energy will be insufficient. Conservation of energy is desirable but utilities cannot enforce this by putting a ceiling on generation or rationing electricity.
Jean-Louis Ricaud of Cogema gave an up-beat account of MOX usage in Europe where 30 reactors are using MOX fuel without any significant differences in safety or operations. The price of manufacturing MOX fuel is coming down and for EDF, MOX fuel is already competitive with uranium fuel. He expected that 10 more plants in Europe would use MOX fuel and, in the next decade, six plants in America may be using MOX fuel from weapons plutonium.
HIGH LEVEL WASTE
The final session dealt with the geological disposal of high level waste. Sumio Masuda, Director of the Geological Isolation Research Project, said that JNC is currently preparing the second progress report on research and development work for a geological repository which will provide the basis for government decisions on siting and regulations.
The first draft of the report shows that Japan will follow similar techniques as have been proposed elsewhere. The canisters of vitrified waste will be encapsulated in thick steel overpacks and placed in a stable rock formation with highly compacted bentonite between the overpack and the rock. Cost estimates have been prepared for a repository suitable for 40 000 canisters considering 11 different scenarios based on either a 500 m deep repository in sedimentary rock or a 1000 m repository in granite. Assuming the repository would be in operation for 60 years and be actively managed for another 300 years, the total costs range from 2.7 trillion yen to 3 trillion yen ($22.5 - 25 billion). It would be preferable to start financing the work now so that the present generation bears its share of the cost. Assuming a 2% discount rate, this would be equivalent to 0.12 - 0.14 yen/kWh although it has not yet been decided if the cost would be borne by the government or the utilities.
Procedures for site selection will be agreed in July 1999 and the entity responsible should be set up before the end of 2000. This may be an independent organisation like its French counterpart, Andra. It is hoped to have an operational repository by 2040. At present, geoscientific studies are being carried out at JNC’s facility in the Tono area and in a mine at Kamaishi.
|Update on the Monju fast reactor incident|
|Kazumoto Ito, Deputy Director of the Monju fast reactor, gave additional information about the famous incident at a special lecture in Tokyo during the recent ICONE 7 meeting. The accident, which occurred on 8 December 1995, involved a leakage of about 640 kg of sodium. The damage was localised, the plant was safely shutdown and there was no leakage of radioactive materials; the accident was rated as level 1 on the INES scale. Nevertheless, the plant remains shut down and it may be several years before full power is reached. The accident was caused by the breakage of a thermocouple thermowell due to high cycle fatigue. Vibrations were caused by symmetrical vortex shedding and the damage was initiated during earlier flow tests at 100% flow. A full safety review has been carried out and the following countermeasures have been proposed: Modification to the thermowells to avoid resonant flow induced vibrations. Improved leak detection equipment. Additional drain lines to give faster drainage of sodium from a damaged loop. Methods of limiting the damage caused by leaks. The additional drains will allow a loop to be drained in 20 minutes, compared to 50 minutes in the original design. Allowing time for leak detection and operator action, it will now be possible to drain a loop in 40 minutes so reducing the amount of sodium spilled. Rapid shutdown of the ventilation systems will be provided to prevent sodium smoke from being carried around the plant which was a major problem during the accident. Also the secondary plant will be divided into four zones with semi-air-tight boundaries between the zones and nitrogen gas fire extinguishing systems will be added to each zone which should be able to extinguish a fire in less than 15 minutes. Additional thermal insulation and heat sink materials will be used to protect the concrete from interaction with molten sodium. These countermeasures have gone through comprehensive safety reviews and planning work is completed. However, licensing approval to make the changes cannot be obtained without the approval of local residents.|