nuclear energy at a crossroads. benefits reactors generate electricity without adding to global...
TRANSCRIPT
Nuclear energy at a crossroads
Benefits
• Reactors generate electricity without adding to global warming/air pollution.
• Small amt. of U gives off large amts. of energy
• 150 lbs. of U 235 = 30 000 000lbs TNT
• U.S. has more energy in known U reserves than coal or gas.
Pool type breeder reactor
Problems
• Reactors and nuclear missiles create radioactive waste with very long half-lives
• Plutonium is highly toxic
• Waste must be stored safely for at least 20 000 years
Canister burial deep underground
Low level waste
• Source: medical procedures, research, cleanup materials.
• 10 years in storage = 100 X less radiation
• May be removed later to landfills.
Maxey Flats storage facility, KY
High level waste
• From N power plants and N missiles
• Material takes
720 000+years to decay
• Best option: deep burial underground
• Prevents escape into air or ground water.
Yucca mountain, NV
Disposal options
Why not………..
• Bury it under the ocean floor?
too expensive
• Blast it into space?
too expensive, could leak into atmosphere, could explode on takeoff
• Recycle it?
already being done
Transmutation/ recycling N fuel
• Changes high level waste to elements w/shorter ½ lives
• Breeder reactor: spent fuel is reprocessed to convert Pu to U for reuse
• Hybrid reactor: uses neutrons to convert U to smaller, less toxic elements (experimental)
Fast breeder reactor, Japan
The H bomb
• Exploded 1952 on Eniwetok island, S. Pacific• 9+ countries now have nuclear weapons.
Nuclear proliferation
• N power plants/ U refineries create Plutonium that can be used to make N bombs.
• When a country builds a N power plant, it causes international concern.
• Are they using it for electricity, or for war?
Fast breederreactor
US Peacekeeper nuclear missile
1954 H bomb
Humans have unlocked the power inside an atomWhat we do with that power is a question we must all ask and answer for ourselves.
‘Bravo’ Hydrogen bomb crater, 1956 Bikini atoll