Nuclear power is the use of sustained nuclear fission to generate heat and electricity.
Nuclear Power Plants provide about 6% of the world's energy and 13–14% of the world's electricity with the USA,France and Japan together accounting for about 50% of nuclear generated electricity.
The USA produces the most nuclear energy, with nuclear power providing 19% of the electricity it consumes, while France produces the highest percentage of its electrical energy from nuclear reactors—80% as of 2006.
In the European Union(EU) as a whole, nuclear energy provides 30% of the electricity.
Nuclear Energy Policy differs among European Union countries, and some, such as Austria,Estonia and Italy have no active nuclear power stations. In comparison, France has a large number of these plants, with 16 multi-unit stations in current use.
International Atomic Energy Agency (IAEA) in 2007 reported there were 439 nuclear power reactors in operation in the world operating in 31 countries.
Three Mile Island Accident(1979)
The '' Three Mile Island accident '' was a Nuclear Meltdown which occurred at the power plant in Dauphin County,Pennysylvania,USA on March 28, 1979 that resulted in the release of moderate amounts of Radioactive Gases and Radioactive Iodine into the environment.Schools were closed and residents were urged to stay indoors. Farmers were told to keep their animals under cover and on stored feed.The evacuation zone was extended to a 20 mile radius on Friday March 30. Within days, 140,000 people had left the area. More than half of the 663,500 population. within the 20-mile radius remained in that area.According to a survey conducted in April 1979, 98% of the evacuees had returned to their homes within three weeks.
Chernobyl Disaster(1986)
The Chernobyl nuclear accident occurred on April 26,1986 at the Chernobyl Nuclear Power Plant in Ukraine which was under the direct jurisdiction of the central authorities in Moscow.An explosion and fire released large quantities of radioactive contamination into the atmosphere, which spread over much of Western USSR and Europe. It is widely considered to have been the worst nuclear power plant plant accident in history and is one of only two classified as a level 7 event on the International Nuclear Event Scale(the other being the Fukushima Daiichi Nuclear Disaster)
The disaster began during a systems test on Saturday, 26 April 1986 at reactor number four of the Chernobyl plant.There was a sudden power output surge, and when an emergency shutdown was attempted, a more extreme spike in power output occurred, which led to a reactor vessel rupture and a series of explosions.
The plume drifted over large parts of the Western Soviet Union and Europe.From 1986 to 2000, 350,400 people were evacuated and resettled from the most severely contaminated areas of Belarus,Russia and Ukraine.
The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report places the total confirmed deaths from radiation at 64 as of 2008. The World Health Organization (WHO) suggests it could reach 4,000 civilian deaths. Other reports from environmental groups have put the predicted death toll at between 30,000 and 200,000 deaths.
Nuclear Power Plants provide about 6% of the world's energy and 13–14% of the world's electricity with the USA,France and Japan together accounting for about 50% of nuclear generated electricity.
The USA produces the most nuclear energy, with nuclear power providing 19% of the electricity it consumes, while France produces the highest percentage of its electrical energy from nuclear reactors—80% as of 2006.
In the European Union(EU) as a whole, nuclear energy provides 30% of the electricity.
Nuclear Energy Policy differs among European Union countries, and some, such as Austria,Estonia and Italy have no active nuclear power stations. In comparison, France has a large number of these plants, with 16 multi-unit stations in current use.
International Atomic Energy Agency (IAEA) in 2007 reported there were 439 nuclear power reactors in operation in the world operating in 31 countries.
Support for Nuclear Power
World Nuclear Association,London,U.K
and
International Atomic Energy Agency(IAEA)
contend that nuclear power is a sustainable energy source that reduces carbon emissions.
Opposition for Nuclear Power
Greenpeace International,Vancouver,Canada
and
Nuclear Information and Resource Service (NIRS) Takoma Park Maryland,USA
believe that nuclear power poses many threats to people and the environment.
Nuclear Power Plants Accidents
Three Mile Island Accident(1979)
The '' Three Mile Island accident '' was a Nuclear Meltdown which occurred at the power plant in Dauphin County,Pennysylvania,USA on March 28, 1979 that resulted in the release of moderate amounts of Radioactive Gases and Radioactive Iodine into the environment.Schools were closed and residents were urged to stay indoors. Farmers were told to keep their animals under cover and on stored feed.The evacuation zone was extended to a 20 mile radius on Friday March 30. Within days, 140,000 people had left the area. More than half of the 663,500 population. within the 20-mile radius remained in that area.According to a survey conducted in April 1979, 98% of the evacuees had returned to their homes within three weeks.
Chernobyl Disaster(1986)
The Chernobyl nuclear accident occurred on April 26,1986 at the Chernobyl Nuclear Power Plant in Ukraine which was under the direct jurisdiction of the central authorities in Moscow.An explosion and fire released large quantities of radioactive contamination into the atmosphere, which spread over much of Western USSR and Europe. It is widely considered to have been the worst nuclear power plant plant accident in history and is one of only two classified as a level 7 event on the International Nuclear Event Scale(the other being the Fukushima Daiichi Nuclear Disaster)
The disaster began during a systems test on Saturday, 26 April 1986 at reactor number four of the Chernobyl plant.There was a sudden power output surge, and when an emergency shutdown was attempted, a more extreme spike in power output occurred, which led to a reactor vessel rupture and a series of explosions.
The plume drifted over large parts of the Western Soviet Union and Europe.From 1986 to 2000, 350,400 people were evacuated and resettled from the most severely contaminated areas of Belarus,Russia and Ukraine.
The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report places the total confirmed deaths from radiation at 64 as of 2008. The World Health Organization (WHO) suggests it could reach 4,000 civilian deaths. Other reports from environmental groups have put the predicted death toll at between 30,000 and 200,000 deaths.
Fukushima Daiichi Nuclear Disaster (2011)
The Fukushima Daiichi nuclear disaster is a series of Equipment failures,Nuclear Meltdowns and Releases of Radioactive Materials at the Fukushima I Nuclear Power Plant following the Tohoku Earthquake and Tsunami on March 11,2011
The plant comprises 6 separate boiling water reactors.At the time of the quake, Reactor 4 had been de-fuelled while 5 and 6 were in cold shutdown for planned maintenance.The remaining reactors shut down automatically after the earthquake, and emergency generators came online to control electronics and coolant systems. The tsunami broke the reactors' connection to the power grid, leading the reactors to begin to overheat. The flooding and earthquake damage hindered external assistance.In the hours and days that followed, reactors 1, 2 and 3 experienced full meltdown.As workers struggled to cool and shut down the reactors, several hydrogen explosions occurred.The government ordered that seawater be used to attempt to cool the reactors—this had the effect of ruining the reactors entirely. As the water levels in the fuel rods pools dropped, they began to overheat. Fears of radioactivity releases led to a 20 km (12 mi)-radius evacuation around the plant, while workers suffered radiation exposure and were temporarily evacuated at various times. Electrical power was slowly restored for some of the reactors, allowing for automated cooling.
Japanese officials initially assessed the accident as Level 4 on the International Nuclear Event Scale (INES) despite the views of other international agencies that it should be higher. The level was successively raised to 5 and eventually to 7, the maximum scale value.
A few of the plant's workers were severely injured or killed by the disaster conditions resulting from the earthquake. There were no immediate deaths due to direct radiation exposures, but at least six workers have exceeded lifetime legal limits for radiation and more than 300 have received significant radiation doses.
Rethink of Nuclear Energy Policy after Fukushima Daiichi Nuclear Disaster in 2011
Germany decided to close all its reactors by 2022, and Italy has banned nuclear power.
Following Fukushima, the International Energy Agency (IEA)Paris,France halved its estimate of additional nuclear generating capacity to be built by 2035
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