Are you prepared?...

1. Are you prepared?... http://www.youtube.com/watch?v=vZAJbJc1ayc start 2:27

3. Renewable or Non-Renewable?

4. What is Radiation? Uranium 92U238.02891 How many protons? How many electrons? How many neutrons? 6 C Carbon 12.011 92 protons 92 electrons 146 neutrons

5. What is Radiation? • Radiation = particles given off by unstable atoms. • 3 Types: • Alpha (α) • Travels few inches • Blocked by paper (skin) • Beta (β) • Travels few feet • Blocked by aluminum, glass • Gamma (γ) • Travels far • Blocked by lead (steel & concrete).

6. Background Radiation • The amount of radiation we are exposed to daily from the environment • Average = 360 millirem/year or 3 millisieverts

7. www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

8. Effects of Radiation • Genetic damages: from mutations that alter genes • defects can become apparent in the next generation • Somatic damages: to tissue, such as burns, miscarriages & cancers www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

10. Nuclear waste • Power plants produce radioactive wastes • mostly spent fuel rods (3-4 years) • each reactor produces about 20-30 tons yearly • Currently stored in pools on site and then above ground casks • some remain dangerous for tens of thousands of years • How should we store this waste?

13. Yucca Mountain

14. Options for Waste • Keep onsight • Bury • Shoot into space • Bury in ocean floor • Bury in Antarctica • Change it into harmless or reprocess to make new fuel

15. Low-Level & High Level Radioactive Waste Emit small amounts of ionizing radiation Stored 100-500 years 19401970: put in steel drums, dumped in ocean (still UK & Pakistan) 1970+: gov’t run landfills • Stored for thousands of years • Mostly spent fuel rods (240,000 yrs) • Safety debate • Options: • Keep onsight • Bury • Shoot into space • Bury in ocean floor • Bury in Antarctica • Change it into harmless

16. www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

17. Nuclear Energy • The energy that exists within the nucleus of an atom. • Nuclear Fission = the release of energy from the splitting of atoms! • Nuclear Fusion = the combining of two smaller atoms into one larger atom. • http://videos.howstuffworks.com/discovery/29389-assignment-discovery-nuclear-basics-video.htm

18. Nuclear Fission http://www.youtube.com/watch?v=Pmy5fivI_4U

19. Nuclear Fusion

20. Nulear Change Nuclear Fission Nuclear Fusion Sun and stars, some weapons 2 small (light) isotopes are forced together H + H = He Need temps > 100,000,000ºC Releases more E than fission • Bombs & power plants • Big, unstable isotopes are struck by neutrons, which splits the isotope’s nuclei • More neutrons “shoot out” to strike nearby isotopes, causing a chain reaction.

21. 437 commercial reactors in 32 countries, producing 17% electricity

23. Nuclear Power Plant a controlled nuclear fission chain reaction heats water produce high-pressure steam that turns turbines which turns generator and creates electricity. http://www.howstuffworks.com/nuclear-power2.htm

24. Controlled Nuclear Fission Reaction

25. http://www.animatedsoftware.com/environm/nukequiz/nukequiz_one/nuke_parts/reactor_parts.swfhttp://www.animatedsoftware.com/environm/nukequiz/nukequiz_one/nuke_parts/reactor_parts.swf www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

26. Boiling Water Reactor

27. Pressurized Water Reactor Boiling Water Reactor

28. http://www.ida.liu.se/~her/npp/demo.html

29. Where nuclear fission occurs. Surrounded by thick concrete, steel & lead. Blocks all radiation! Nuclear Reactor

30. Fuel Rods 35,000 – 70,000 fuel rods 3% Uranium-235 pellets In water (moderator) Control Rods absorb extra neutrons Control the chain reaction Inside the Reactor http://online.wsj.com/article/SB10001424052748704396504576205000098975380.html#project%3DFUELASSEMBLY0317%26articleTabs%3Dinteractive

31. Cooling Tower • Water is the coolant in the system. • Tower is used to condense hot steam to liquid water. • Usually taken from river, lake, ocean. • Water can be reused.

32. Decommissioning Life span of a power plant = 15-40 years Parts wear out, Fuel is spent Plant is shut down Highly radioactive for 240,000 years Must store for 10 times the half-life What can we do with them?

33. Half-Life = time needed for one-half of the nuclei in a radioisotope to decay and emit their radiation to form a stable isotope Half-time emitted Uranium 235 710 million yrs alpha, gamma Plutonium 239 24,000 yrs alpha, gamma www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

34. When people think about nuclear power they think about… • Effects of radiation • Nuclear waste disposal • Nuclear disasters

35. Three Mile Island - 1979 • .008 sieverts over 7 days • Remember 1,000 sieverts is radiation sickness • 5,000 is death http://maps.google.com/maps?um=1&hl=en&q=three%20mile%20island%20plant%20map&ndsp=20&safe=on&ie=UTF-8&sa=N&tab=il

36. Chernobyl - 1986 • 300 sieverts per hour • 240 acute radiation sickness; 31 died within 3 months • 100,000 people evacuated • Some claim up to 985,000 deaths due to Chernobyl

37. Chernobyl Fallout

38. Japan • 0.4 sieverts per hour • 70,000 people evacuated • 140,000 told to stay inside

39. http://streaming.discoveryeducation.com/search/assetDetail.cfm?guidAssetID=BE0FB49C-7C70-4C56-95F2-B3904BC9077Fhttp://streaming.discoveryeducation.com/search/assetDetail.cfm?guidAssetID=BE0FB49C-7C70-4C56-95F2-B3904BC9077F • 10 min video on nuclear energy • Fission, fusion, overview