1. Nuclear Energy Dawn of Nuclear Age

2. Overview History Introduction to Nuclear Energy Atoms and radioactivity Pros and Cons of Nuclear Energy Future of Nuclear Power

3. Early History of Nuclear Power

4. 4 Development of nuclear power Development of nuclear power At present there are more than 440 nuclear power plants in the World 1954 the first nuclear power plant in USSR 1957 first commercial nuclear power plant in USA

5. History of nuclear power 1938– Scientists study Uranium nucleus 1941 – Manhattan Project begins 1942 – Controlled nuclear chain reaction 1945 – U.S. uses two atomic bombs on Japan 1949 – Soviets develop atomic bomb 1952 – U.S. tests hydrogen bomb 1954: first commercial nuclear power program 1955 – First U.S. nuclear submarine

6. Manhattan Project Secret government project to create atomic weapons during World War II After the war, the government encouraged “the development of nuclear energy for peaceful civilian purposes.” This led to the technology used in nuclear plants today

7. power was gradually increased until the first usable amount of electricity was generated, lighting four light bulbs and introducing nuclear generated power for the first time In 1953, the EBR-1 was creating one new atom of nuclear fuel for every atom burned, thus the reactor could sustain its own operation With this creation of new cores, enough energy was created to fuel additional reactors A few years later, the town of Arco, Idaho became the world's first community to get its entire power supply from a nuclear reactor This was achieved by temporarily attaching the town’s power grid to the reactor’s turbines

8. Early Beginning of Commission Atomic Energy Commission (AEC) established by Congress in 1946 as part of the Atomic Energy Act AEC authorized the construction of Experimental Breeder Reactor I ( EBR-1) at a site in Idaho in 1949

9. Atoms for Peace Began in 1953 and was designed by Eisenhower specifically to promote peaceful, commercial applications of atomic energy after the Manhattan Project and atomic bombings on Japan Public support for nuclear energy grew, federal nuclear energy programs shifted their focus to advancing reactor technologies With this came the support of utility companies, which saw nuclear energy as a cheap and environmentally safe alternative energy choice Program to justify nuclear technology Proposals for power, canal-building, exports First commercial power plant, Illinois 1960

10. Nuclear power Today around the globe 17% of world’s electricity from nuclear power ◦U.S. about 20% (2nd largest source) ◦Leader is France  About 80% of its power from nuclear 440+ nuclear plants in 31 countries ◦103 of them in the U.S. ◦Built none since 1970s (Wisconsin as leader).

11. Countries Generating Most Nuclear Power CountryTotal MW USA99,784 France58,493 Japan38,875 Germany22,657 Russia19,843 Canada15,755 Ukraine12,679 United Kingdom11,720 Sweden10,002 South Korea8,170

12. Introduction to Nuclear Energy

13. Matter and Energy Previous studies have taught us that “matter and energy cannot be created nor destroyed” We now need to understand that Matter and Energy are two forms of the same thing

14. Mass Matter can be changed into Energy Einstein’s formula above tells us how the change occurs In the equation above: E = Energy m = Mass c = Speed of Light (Universal Constant) The equation may be read as follows: Energy (E) is equal to Mass (m) multiplied by the Speed of Light (c) squared This tells us that a small amount of mass can be converted into a very large amount of energy because the speed of light (c) is an extremely large number Energy Light Speed Light Speed E = mc 2

15. Nuclear reactions deal with interactions between the nuclei of atoms Both fission and fusion processes deal with matter and energy Introduction to Nuclear Energy

16. Nuclear energy ◦Energy released by nuclear fission or fusion Nuclear fission ◦Splitting of an atomic nucleus into two smaller fragments, accompanied by the release of a large amount of energy Nuclear fusion ◦Joining of two lightweight atomic nuclei into a single, heavier nucleus, accompanied by the release of a large amount of energy

17. Fission Fission is the process of splitting an atomic nucleus into fission fragments The fission fragments are generally in the form of smaller atomic nuclei and neutrons Large amounts of energy are produced by the fission process Fissile nuclei are generally heavy atoms with large numbers of nucleons The nuclei of such heavy atoms are struck by neutrons initiating the fission process Fission occurs due to electrostatic repulsion created by large numbers of protons within the nuclei of heavy atoms

18. Fission A classic example of a fission reaction is that of U-235: U-235 + 1 Neutron 2 Neutrons + Kr-92 + Ba-142 + Energy In this example, a stray neutron strikes an atom of U-235. It absorbs the neutron and becomes an unstable atom of U-236. It then undergoes fission. Notice that more neutrons are released in the reaction. These neutrons can strike other U-235 atoms to initiate their fission.

19. Fusion Fusion is a nuclear reaction whereby two light atomic nuclei fuse or combine to form a single larger, heavier nucleus The fusion process generates tremendous amounts of energy; refer back to Einstein’s equation For fusion to occur, a large amount of energy is needed to overcome the electrical charges of the nuclei and fuse them together Fusion reactions do not occur naturally on our planet but are the principal type of reaction found in stars The large masses, densities, and high temperatures of stars provide the initial energies needed to fuel fusion reactions The sun fuses hydrogen atoms to produce helium, subatomic particles, and vast amounts of energy

20. Fusion Way of the future?? ◦Produces no high-level waste ◦Fuel is hydrogen (plenty of it!) Problems ◦It takes very high temperatures (millions of degrees) to make atoms fuse ◦Confining the plasma after it is formed Scientists have yet to be able to create energy from fusion

21. Atoms and Radioactivity Nucleus ◦Comprised of protons (+) and neutrons (neutral) Electrons (-) orbit around nucleus Neutral atoms ◦Same number of protons and electrons

22. Atoms and Radioactivity Atomic mass ◦Sum of the protons and neutrons in an atom Atomic number ◦Number of protons per atom ◦Each element has its own atomic number Isotope ◦Atoms of an element having same number of protons but different number of neutrons

23. Radioactive Isotope Unstable isotope Radioactive Decay ◦Emission of energetic particles or rays from unstable atomic nuclei Each isotope decays based on its own half-life Half-life of U-238 is 4.468×10 9 years Half life of U-235 is 7.04× 10 8 years

24. Radioactive Isotope Half-lives

25. Nuclear Fuel Cycle ◦processes involved in producing the fuel used in nuclear reactors and in disposing of radioactive (nuclear) wastes

26. How Electricity is Produced

27. Pros and Cons of Nuclear Energy Pros ◦Less of an immediate environmental impact compared to fossil fuels

28. Pros and Cons of Nuclear Energy Pros (continued) ◦Carbon-free source of electricity- no greenhouse gases emitted ◦May be able to generate H-fuel Cons ◦Generates radioactive waste ◦Many steps require fossil fuels (mining and disposal) ◦Expensive

29. Cost of Electricity from Nuclear Energy Cost is very high 20% of US electricity is from Nuclear Energy ◦Affordable due to government subsidies Expensive to build nuclear power plants ◦Long cost-recovery time Fixing technical and safety issues in existing plants is expensive

30. Safety Issues in Nuclear Power Plants Meltdown ◦At high temperatures the metal encasing the uranium fuel can melt, releasing radiation Probability of meltdown or other accident is low Public perception is that nuclear power is not safe Sites of major accidents: ◦Three Mile Island ◦Chornobyl (Ukraine)

31. Nuclear Energy and Nuclear Weapons 31 countries use nuclear energy to create electricity These countries have access to spent fuel needed to make nuclear weapons Safe storage and handling of these weapons is a concern

32. Radioactive Waste Low-level radioactive waste- ◦Radioactive solids, liquids, or gasses that give off small amounts of ionizing radiation High-level radioactive waste- ◦Radioactive solids, liquids, or gasses that give off large amounts of ionizing radiation

33. Decommissioning Nuclear Power Plants Licensed to operate for 40 years ◦Several have received 20-year extensions Power plants cannot be abandoned when they are shut down Three solutions ◦Storage ◦Entombment ◦Decommissioning (dismantling)