On March 11, 2011 one of the largest earthquakes occurred on the East coast of Northern Japan which generated a massive tsunami and killed around 20,000 people. Due to this there were disruptions in electricity, water supply, and railway service. The Fukushima DAiichi nuclear power plant was severely affected because of these disruptions.
Fukushima Daiichi Disaster
The damages that were caused by this tsunami resulted in equipment problems in the Fukushima DAiichi nuclear plant. Since there was no power and water was not being cooled the cores of three of the units overheated and melted. This caused high temperatures and the creation of hydrogen which lead to explosions. Because of these explosions high radioactive debris was released into the air during the first few days. There was also a leak of contaminated water to sea for months.
A lot of steam was produced in the reactor pressure vessels because no heat removal was occurring by an outside heat exchanger. AS pressure started to rise, the steam was moving into the suppression chamber, and the internal temperature continued to raise very quickly. Cooling of this system is provided by outside sources and since this connection to outside sources was disturbed the nuclear machine failed.
Effects
Even though there was significant amounts of radioactive releases there was no effect on the people around. This is because people were very quickly evacuated out of the area and moved to safer places. Certain areas remained off limit to people for a while, and some still do remain off limit.
Radioactive material continues to run off from land into the sea even though fences were present even before the accident. This material can be found in certain species of fish. The Japanese government has been strictly monitoring all of the food from the affected areas so that people refrain from consuming any food that is contaminated with radioactive material.
New Energy Strategies in Japan
Japan expects to rely on nuclear power even more now than before even though this incident occurred. Japan plans on increasing the use of renewable sources, but it is hard for them to change the old habits of nuclear power and fossil fuels. The country has few natural resources so it is hard for them to completely change around their sources of energy from nuclear.
http://fukushima.ans.org
http://www.world-nuclear.org/info/safety-and-security/safety-of-plants/fukushima-accident/
http://www.world-nuclear.org/Features/Fukushima/Situation-at-Fukushima/
http://www.wsj.com/articles/japan-struggles-to-find-balanced-energy-strategy-1431545581