What if . . .

2. What if . . . • There was a power source with an abundant fuel supply? • A source that created no CO2 in generating electricity? • What if . . . .

3. What if . . .that power was nuclear?

4. Coal Domestic fuel Combustion of coal = CO2, SOx, NOx, particulates, Hg Nuclear Domestic fuel No combustion = no air pollutants Mining/processing/ transporting of fuel does create CO2 Waste products highly dangerous Risk of nuclear accident Comparison of coal vs. nuclear

5. The fission reaction – interpret this diagram

7. Compare/contrast to WA Parish – “Lightwater” reactors

8. Controlling the chain reaction • 1. Fuel is 97% U-238, only 3% U-235 • 2. Control rods stop movement of neutrons • 3. Moderating fluid contains Boron

9. South Texas Project power plant • Photo slide show!

10. Reactor core & fuel rod assembly

11. Check for understanding • Explain the fission reaction • What is the difference between fission and fusion? • How is a nuclear power plant the same as a coal-fired power plant? • How is a nuclear power plant different from a coal-fired power plant? • How is moderating fluid used to control the fission reaction?

12. Comparison of coal vs. nuclear Coal Domestic fuel Combustion of coal = CO2, SOx, NOx, particulates, Hg Nuclear Domestic fuel No combustion = no air pollutants Mining/processing/ transporting of fuel does create CO2 Waste products highly dangerous Risk of nuclear accident

13. Radiation – the dose makes the poison • Background radiation from planet .1-.2/yr • X-ray 1 rem • Upper limit for job exposure 5 rems/yr • 10 rem/incident – embryo show abnormalities • 100/incident – probable leukemia • 1,000/incident – nausea, harm to intestines, death in 2 weeks • 10,000/incident – coma, death in two days • 100,000/incident – immediate death

14. 104 Nuclear power plants in the US

15. Low level waste High Level waste Nuclear waste

16. Two kinds of nuclear waste • Low level waste • Protective gear • X-ray wastes • Medical wastes • Stored in near-surface waste facilities • Remains radioactive about 100 years

17. Management of low level waste

18. Management of low level waste – Andrews county Texas to accept waste from 36 states

20. Second kind of nuclear waste • High Level waste • Radioactive 10,000 years • Spent fuel rods • Currently stored on-site in the US

21. High Level waste Radioactive 10,000 years Spent fuel rods Currently stored on-site Half-life: the amount of time required for half of the nuclei in a radioisotope to emit its radiation. Potassium-42 12hrs Iodine-131 8 days Strontium-90 28 yrs Carbon-14 5,370 yrs U-235 710 million yrs U-238 4.5 billion yrs How long will it remain dangerous?

22. Half life – how long will it last? • Iodine-131 (8 days) • If you had 1kg of Iodine-131, how much radioactive material would you have in 32 days?

23. Radioactive decay of Uranium

24. 104 Nuclear reactors (at 65 sites)in the US

26. Yucca Mountain, Nevada – cancelled project

28. Alternatives? Develop reactors that use 99.9% of fuels – “4th generation” reactors – won’t be ready until 2030 ****Big need for engineers and creative thinkers!!!

29. Alternatives? • Reprocessing – France shut last coal power plant in 2004. 56 nuclear reactors. Reprocessed fuel is used again; waste is stored in chunks of glass in stainless steel containers a few meters underground and loses radioactivity quickly. • Recovers 25% unused Uranium and Plutonium • Reduces volume of waste to 20% of original volume

30. One nuclear accident can really ruin your whole day. Nuclear accidents

31. Three Mile Island • 1979 Pennsylvania • Mechanical and human failure • Lost coolant water, only partial meltdown

32. 104 Nuclear power plants in the US – possible fallout effects

33. Chernobyl • April 26, 1986 • Human error led to meltdown • 116,000 people evacuated • Area the size of Florida contaminated • Cesium 137 and Iodine 131 released – reactive carcinogen • Thyroid cancer rates in children in Belarus are 100 times higher than preaccident levels

35. Fukushima Daiichi

36. Fukushima Daiichi • Tsunami of March 11, 2011 destabilized plant • Full meltdown in three reactors due to inability to cool reactor cores • Seawater used to cool cores, ruined reactors; loss of moderating fluid • Released about 1/10 of radioactive material as Chernobyl (Cesium-137) • Japanese still concerned about food supply (US fisheries?) • 20 km exclusion zone currently in place

37. Current Fukishima status (CNN: Some residents to 'come home' to Fukushima nuclear disaster zone 2/24/14) • April 1, some 350 people from the Miyakoji district of Tamura city will be allowed to head back to their homes permanently, according to the country's Reconstruction Agency. Some 31,000 people could eventually return home, it added. • The government says about 138,000 Fukushima residents are still living in temporary accommodation. • Areas are declared suitable for habitation if residents are exposed to a maximum of 20 millisieverts of radiation per year. Officials have said they would like to get radiation exposure down to one millisievert a year.

38. The containment effort at the wrecked Fukushima-Daichi plant has been beset by problems, with regular reports of leaks of contaminated material. Last week, an estimated 100 metric tons of highly contaminated water flowed over a barrier around a containment tank and is being absorbed into the ground, plant operators, Tokyo Electric Power Company (TEPCO), said in a statement -- though it denied there was any leakage into the nearby Pacific Ocean.

39. National Geographic returns to Chernobyl • national geographic video