Nuclear Energy: Power Generation and Safety Considerations

1. Nuclear Energy

2. Nuclear Energy • most striking development in sources of power in recent years. • Release of the atom

3. How long….. • Have we known about atomic power?

4. Ancient Greeks • included atomic theory as one of their philosophical studies • Knowledge about atoms was developed in the 17th century

5. Early 1900’s • theory became clarified

6. 1940”s • atom was split • resulting power was put to work

7. Nuclear fission • the nuclei of heavy atoms are split under bombardment by neutrons

8. Nuclear fission • when a sufficient amount of fissionable material is brought together • chain reaction occurs

9. Nuclear fission • splitting atoms and releasing a tremendous amount of heat

10. Nuclear fission • approximately 20,000 times as much heat and energy is released from uranium fuels as from an equivalent amount of coal

11. Use of fission power • 1945 • first large scale use • atomic bombs were used by the US to knock Japan out of WWII

12. WWII • since then attention has been given to the peaceful uses of atomic energy

13. 1980 • the amount of electrical power generated by nuclear power plants was about 11% of the total electrical supplies in the US

14. Energy from fission • atomic energy in the US today is produced by the process known as nuclear fission

15. Fuel supplies • adequate supplies for nuclear power • major mineral sources for nuclear power • Uranium 238 • Thorium 232

16. Fuel • from those - U 235 and Plutonium 239 can be produced • in the early stages of development US relied heavily upon imports of uranium

17. Fuel • from South Africa and Canada

18. 1950’s and 60’s • western US deposits were developed • Bureau of Mines reported that -

19. . • “Domestic production is adequate to supply present and near-future domestic requirements.”

20. In 1981 • US was still the world leading miner of uranium

21. Nuclear Fusion • Fusion is combining together • the atoms are fused together rather than split apart • possibilities for nuclear fusion are much greater than those for nuclear fission

22. Fusion • problems • process is so difficult to control that it is questionable whether commercial adaptation will ever be economically feasible

23. Problems • fusion requires extreme pressure and temperatures • as high as 100 million degrees

24. Problems • such heat was achieved by the Hydrogen bomb • by first setting off a fission explosion

25. Fuel for fusion • fusion reactors would be fueled by deuterium • an isotope of hydrogen • available in almost unlimited supply in sea water

26. US Government • demonstration fusion reactor • hopes to have in operation by 2015

27. LWR • Light Water Reactor • use ordinary water • have been in commercial use since 1957

28. LWR • free from environmental problems of coal fired electric power plants

29. LWR disadvantages • potential of a reactor explosion • contamination form atomic wastes • construction costs and technical problems

30. Safety? • 1974 report stated of Nuclear Power

31. Safety? • “its use poses serious environmental issues, including reactor safety, radioactive waste management and nuclear theft……..

32. Safety? • A very hazardous enterprise.”

33. Three Mile Island • March 28, 1979 • Human and mechanical failure led to the release of a considerable amount of radioactivity

34. Three Mile Island • evacuation of preschool children and pregnant women within five miles of the plant

35. Three Mile Island • Nevertheless • 67 nuclear facilities are expected to continued operating • 90 were planned for construction by 1990

36. Safety Institutions • two • Nuclear Safety Analysis Center • monitors performance of safety

37. Safety Institutions • Institute of Nuclear Power • inspects existing reactors and evaluates them

38. Industrial Significance • peaceful use • development of under-seas and space nuclear power • medical use of radioisotopes

39. Industrial Significance • research in nuclear physics • ensnarled by many problems technological, economic and social

40. Breeder Reactors • fast breeder reactors • more efficient to operate than LWR’s are undergoing experiment

41. Breeder Reactors • two types • LMFBR • Liquid Metal Fast Breeder Reactor

42. Breeder Reactors • GCFBR • Gas cooled fast breeder reactor

43. Breeder Reactors • they produce more fuel than they consume • more efficient than LWR’s

44. Breeder Reactors • can use 50-70% of the uranium mined in contrast to only 2% by the LWR

45. Breeder Reactors • safety problems for the LMFBR may prove to be more sever than those of the LWR

46. 1950’s • Atomic Energy Commission stated: • all new power plants under construction would be atomic powered

47. 1950’s • nuclear energy would account for one half of all the electricity generated

48. 1950’s forecast • does not seem likely to happen • it takes 10-12 years to get a nuclear plant in operation from the first time it is planned

49. 1950’s forecast • no new plant orders were signed in the early 1980’s due to the Three Mile Island accident.

50. 1974 • American Scientists and Engineers completed a study • assessed the possibilities of accident risks in nuclear reactors…...