The earthquake and the ensuing tsunami resulted in the death of 19, people with still missing and devastated communities up and down the country. Reactors close to the earthquake, including those operating at Fukushima, shut down as designed. However, as a consequence of the flood caused by the tsunami, the backup generators at the Fukushima Daiichi plant, which were meant to pump cooling water through the reactor, were destroyed.
As a result, three cores largely melted over the following three days and there were several hydrogen explosions, as well as the release of nuclear material into the environment. The accident at Fukushima Daiichi did not result in any radiation deaths or cases of radiation sickness, and the United Nations Committee on the Effects of Atomic Radiation UNSCEAR concluded that there will be no observable negative health effects for the public due to radiation.
However, the evacuation of residents resulted in death and suffering, mainly amongst elderly residents in Fukushima, as well as long-term psychosocial health effects and stigmatisation.
Further information can be found in the information page on the Fukushima Daiichi Accident. Shortly after the Chernobyl accident it became evident that the main impacts of nuclear accidents are not radiological, but socio-economic and psychological, driven by misconceptions about the health effects of radiation.
A very similar situation is also seen following the Fukushima Daiichi accident. The fuel rods melted at a temperature of degrees Celsius, and without an effective containment structure, radioactive material and radiation were spewed into the atmosphere, and spread, via wind, to the surrounding area and onward to the rest of Europe.
Japan confirmed there was an explosion at one of its nuclear plants on Saturday following a major earthquake. But the reactor itself appears undamaged, government officials said, and radiation levels have not risen. After watching Japan deal with the threat of a meltdown, Chancellor Merkel said Germany would inspect its nuclear power plants. German protesters formed a 40,person chain in demonstration against nuclear energy.
As Japan struggles to come to terms with the consequences of the worst earthquake, experts say that keeping the country's nuclear power plants under control is of utmost importance.
Visit the new DW website Take a look at the beta version of dw. Go to the new dw. More info OK. Wrong language? Change it here DW. COM has chosen English as your language setting. COM in 30 languages. Deutsche Welle. Audiotrainer Deutschtrainer Die Bienenretter. Officials have implemented a km mile -radius evacuation zone, and have advised people to stay indoors. The US has told its citizens living in the area to stay at least 50 miles away from the power plant. Fortunately, westerly winds have so far blown much of the radioactive material out to sea.
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By using our site, you acknowledge that you have read and understand our Privacy Policy and Terms of Use. Share Twit Share Email. This illustration of a nuclear reactor shows water entering the core and surrounding the fuel rods vertical red bars. When the water level decreases, the fuel rods begin to heat up and face the risk of melting. Image from video below. Citation : How does a nuclear meltdown work?
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. If another atom absorbs one of those neutrons, the atom becomes unstable and undergoes fission itself, releasing more heat and more neutrons.
The chain reaction becomes self-sustaining, producing a steady supply of heat to boil water, drive steam turbines and thereby generate electricity. How much electricity does nuclear power provide in Japan and elsewhere?
With 54 nuclear reactors generating billion kilowatt-hours annually, Japan is the world's third-largest producer of nuclear power, after the U. The Fukushima Daiichi station, which has been hit hard by the March 11 earthquake, houses six of those reactors, all of which came online in the s. Worldwide, nuclear energy accounts for about 15 percent of electricity generation; Japan gets nearly 30 percent of its electricity from its nuclear plants.
The U. About 20 percent of U. What fuels a nuclear reactor? Most nuclear reactors use uranium fuel that has been "enriched" in uranium , an isotope of uranium that fissions readily.
Isotopes are variants of elements with different atomic masses. Uranium is much more common in nature than uranium but does not fission well, so fuel manufacturers boost the uranium content to a few percent, which is enough to maintain a continuous fission reaction and generate electricity.
Enriched uranium is manufactured into fuel rods that are encased in metal cladding made of alloys such as zirconium. Reactor No. How do you turn off a nuclear reaction? Sustained nuclear fission reactions rely on the passing of neutrons from one atom to another—the neutrons released in one atom's fissioning trigger the fissioning of the next atom.
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