Nuclear Energy Prof Park UTI 111 Essex County College Nuclear Energy Around the World As of September 2009 30 countries worldwide were operating 436 nuclear reactors for electricity generation and 53 new nuclear plants were under construction in 14 countries Nuclear power plants provided about 14 percent of the world s electricity production in 2008 In total 15 countries relied on nuclear energy to supply at least one quarter of their total electricity Nuclear Energy Around the World Countries generating the largest percentage of their electricity in 2008 from nuclear energy were Country Percent Country Percent France 76 2 Lithuania 72 9 Slovakia 56 4 Belgium 53 8 Ukraine 47 4 Sweden 42 0 Slovenia 41 7 Armenia 39 4 Switzerland 39 2 Hungary 37 2 S Korea 35 6 Bulgaria 32 9 U S Nuclear Power Plants Nuclear energy provides almost 20 percent of the United States electricity and is its No 1 source of emission free electricity Number of operating reactors 104 35 boiling water reactors 69 pressurized water reactors 14 BWR plants have one reactor nine have two reactors one has three reactors 15 PWR plants have one reactor 24 have two reactors two have three reactors U S Nuclear Power Plants Companies licensed to operate nuclear reactors 32 Number of states with operating reactors 31 In six states for 2008 nuclear makes up the largest percentage of their electricity generated State Percent State Percent Vermont 79 7 Connecticut 51 2 South Carolina 50 9 New Jersey 50 4 New Hampshire 41 0 New York 31 0 Largest U S nuclear plant Palo Verde Arizona 3 reactors at 1 311 1 314 1 247 megawatts MW each for a total of 3 872 MW Smallest U S nuclear plant Ft Calhoun Neb 1 reactor at 478 MW Oldest operating nuclear plant year Oyster Creek in New Jersey operating license issued April 1969 Nuclear Power Plants in NJ Capacity MW 2008 3 year Average Generation MWh Capacity Factor Hope Creek 1 061 9 992 387 95 6 Oyster Creek 619 4 664 005 88 4 Salem 1 1 174 9 327 413 93 0 Salem 2 1 130 8 210 993 90 9 Total 3 984 32 194 798 91 9 Nuclear Energy Is Energy from Atoms Nuclear energy is energy in the nucleus core of an atom Atoms are tiny particles that make up every object in the universe There is enormous energy in the bonds that hold atoms together Nuclear energy can be used to make electricity But first the energy must be released It can be released from atoms in two ways nuclear fusion and nuclear fission Nuclear Energy Is Energy from Atoms In nuclear fission atoms are split apart to form smaller atoms releasing energy Nuclear power plants use this energy to produce electricity In nuclear fusion energy is released when atoms are combined or fused together to form a larger atom This is how the sun produces energy Fusion is the subject of ongoing research but it is not yet clear that it will ever be a commercially viable technology for electricity generation Nuclear Fuel Uranium The fuel most widely used by nuclear plants for nuclear fission is uranium Uranium is nonrenewable though it is a common metal found in rocks all over the world Nuclear plants use a certain kind of uranium referred to as U 235 This kind of uranium is used as fuel because its atoms are easily split apart Though uranium is quite common about 100 times more common than silver U 235 is relatively rare Most U S uranium is mined in the Western United States Once uranium is mined the U 235 must be extracted and processed before it can be used as a fuel Nuclear Fuel Uranium During nuclear fission a small particle called a neutron hits the uranium atom and splits it releasing a great amount of energy as heat and radiation More neutrons are also released These neutrons go on to bombard other uranium atoms and the process repeats itself over and over again This is called a chain reaction Drawing of How Fission Splits the Uranium Atom Milestones in the History of Nuclear Energy December 2 1942 The Nuclear Age began at the University of Chicago when Enrico Fermi made a chain reaction in a pile of uranium August 6 1945 The United States dropped an atomic bomb on Hiroshima Japan killing over 100 000 August 9 1945 The United States dropped an atomic bomb on Nagasaki Japan killing over 40 000 November 1 1952 The first large version of the hydrogen bomb thousands of times more powerful than the atomic bomb was exploded by the United States for testing purposes February 21 1956 The first major nuclear power plant opened in England A more in depth and detailed history of nuclear energy is on the nuclear past page Advantages of Nuclear Energy The Earth has limited supplies of coal and oil Nuclear power plants could still produce electricity after coal and oil become scarce Nuclear power plants need less fuel than ones which burn fossil fuels One ton of uranium produces more energy than is produced by several million tons of coal or several million barrels of oil Coal and oil burning plants pollute the air Welloperated nuclear power plants do not release contaminants into the environment Disadvantages of Nuclear Energy The nations of the world now have more than enough nuclear bombs to kill every person on Earth The two most powerful nations Russia and the United States have about 50 000 nuclear weapons between them What if there were to be a nuclear war What if terrorists got their hands on nuclear weapons Or what if nuclear weapons were launched by accident One possible type of reactor disaster is known as a meltdown In such an accident the fission reaction goes out of control leading to a nuclear explosion and the emission of great amounts of radiation In 1979 the cooling system failed at the Three Mile Island nuclear reactor near Harrisburg Pennsylvania Radiation leaked forcing tens of thousands of people to flee The problem was solved minutes before a total meltdown would have occurred Fortunately there were no deaths In 1986 a much worse disaster struck Russia s Chernobyl nuclear power plant In this incident a large amount of radiation escaped from the reactor Hundreds of thousands of people were exposed to the radiation Several dozen died within a few days In the years to come thousands more may die of cancers induced by the radiation Disadvantages of Nuclear Energy Nuclear explosions produce radiation The nuclear radiation harms the cells of the body which can make people sick or even kill them Illness can strike people years after their exposure to nuclear radiation Nuclear explosions produce radiation The nuclear radiation harms the cells of the