Lessons Learned from the Fukushima Nuclear Accident and Future Energy Policies
September 28, 2011
Mr. Muneo Morokuzu
Project Professor, The University of Tokyo, Graduate school of Public Policy
Whether to resume operations of nuclear power plants in Japan poses serious questions, including how to conduct the “stress tests.” EU member states were convened four days after the Fukushima nuclear accident to discuss countermeasures and the outline of stress tests. They started the re-assessment of nuclear power plants from June 1st based on EU-wide criteria. Japan sent a fact-finding team to get the first-hand information on stress tests conducted in Europe 2 weeks ago, comprising of members from various industries and myself as its team-leader. I observed stress tests in Europe are conducted to assess the design margin and its results will never be used to measure acceptance/rejection or as a condition of operation.
What will be the possible future scenario of Fukushima nuclear accident? Fortunately the worst scenario was avoided, which was the massive release of uranium or plutonium from reactors. Yet serious radioactive contaminations of iodine and cesium have been inflicted. Hydrogen explosions and aftershocks are yet to be concerned, while preventive measures have been taken, such as injecting nitrogen, installing spare pumps and duplex power sources. Treatment of contaminated water and installing a cover over the reactor buildings are most urgently required to completely halt radiation leakage.
Desperate measures have been taken to cool and stabilize the reactor core temperatures. Temperatures at the bottom of pressure vessels of Reactors 1 and 3 have fallen below 100 degrees Celsius, while temperature remains slightly over 100 degrees for Reactor 2. Various issues do remain, but we hope to stabilize the situation in 6 months.
When the earthquake struck at 14:46 on March 11th, the reactor control rods were inserted and the reactors underwent an automatic shutdown, which was the only hopeful outcome from such a massive disaster. The earthquake was followed by the tsunami arriving about an hour later which disabled the emergency diesel generators and triggered the Fukushima nuclear accident. Nuclear Emergency Situation was declared as the Emergency Core Cooling System (ECCS) did not function. The situation worsened and radioactive material was released by deliberate venting from Reactors 1 and 3. Additional massive amount of radioactive materials have spread into the sea and air by hydrogen explosions at Reactors 1, 3, and 4, and damaged reactor containment vessel at Reactor 2.
Tremendous task awaits even after the cleaning up operations are taken based on the announced “roadmap/operation schedule.” Utmost priority should be put on cleaning up the surrounding areas in Fukushima and providing medical aftercare to residents and workers. The government finally announced the “Basic Policy for Emergency Response on Decontamination Work” on August 26th. The government has set an ambitious goal to reduce additional exposure dose to 1mSv a year. In addition, it aims at reducing the estimated annual exposure dose for the general public by approximately 50% within 2 years. As radiation will pose greater negative impact to children than adults, it strives to reduce the estimated annual exposure dose for children by approximately 60% in 2 years at the latest.
Fukushima nuclear accidents have disclosed that regulatory administration is excessively factionalized among various ministries and agencies in this country. This hampered efficient and effective collaboration among Tokyo Electric Power Company (TEPCO), Nuclear and Industrial Safety Agency (NISA) and the Prime Minister’s office.
NISA is mandated with a limited scope of responsibility and authority. Its officers are administrators with relatively low expertise and independence. This was why information and responses provided through press conferences were limited, imprecise and inarticulate. The Japanese government submitted a report to IAEA which enumerates 28 “lessons learned” from this accident. In the report, it points out how to reorganize and reinforce the existing safety regulatory bodies to ensure higher degree of independence, diversity and expertise.
Now, let me move forward on the topic of future energy policies. Crude oil prices fluctuate wildly, requiring countries throughout the world to fight over energy resources. 32 nuclear reactors are being developed in China today. Developing nations cannot afford the high-cost renewable energy sources and they intend to continue pursuing their nuclear policies even after the accident in Fukushima. In this context, the Japanese nuclear policies are attracting worldwide attention.
Renewable energy and nuclear does not contradict each other. Future power sources must create a best mix of the advantages of various energies. It is welcoming to exploit the extensive renewable energy base in Japan, but we also need to secure back-up power supplies in case of power shortage due to climate conditions.
Even though Japan was supposed to be the best prepared country in the world for tsunami, such a scale of disaster destroyed everything ruthlessly. When we look back on the history of mankind and technology, our forerunners have learned by mistake and made steady advancement. If we give up nuclear at this stage, it means we surrender to natural disaster.
Now we face the real test of human wisdom. I believe we are wise enough to learn from the Fukushima accident and succeed in reinforcing safety measures that will win public confidence. Countries throughout the world keep watching on the course Japan takes after this accident. It is our mission to respond to such expectations and improve nuclear safety to make nuclear the essential energy source.