Nuclear Energy Fission

HOW CAN WE USE THIS HEAT TO GENERATE ELECTRICITY?

Nuclear Energy

Thermal Energy

Mechanical Energy

Electrical Energy

NUCLEAR FISSION• During nuclear fission, a uranium nucleus is hit with

a neutron, which causes it to split into smaller nuclei, more neutrons.

IMPORTANT PIECES

IMPORTANT PIECES• Fuel Rods

• The cylindrical tubes that house the nuclear fuel used in a nuclear power plant.

• Control Rods • The cylindrical devices that can be inserted between the

fuel rods to absorb excess neutrons, thus slowing or stopping the fission reaction.

• Moderators • Slow down neutrons to effectively trigger next reaction.

BETTER THAN FOSSIL FUELS• Nuclear fission produces a lot of energy from a little

bit of fuel.E = Δmc2

Mass that is lost is transformed into a lot of heat energy!

1 g of Uranium creates 80 million kJ of

energy.

Fossil Fuel Energy Content (kJ/g)

Oil 43.6

Natural Gas 51.6

Coal 39.3

https://www.wou.edu/las/physci/GS361/Energy_From_Fossil_Fuels.htm

MELTDOWN• Nuclear meltdowns occur when reactions are

uncontrolled, the reactor becomes too hot. • Melts and releases radioactive elements to the environment.

• Nuclear meltdowns are the main reason used to prevent new power plants from being built.

NIMBY Not in My Backyard

• Only 3 accidents to have occurred in over 16,000 cumulative reactor-years in 33 countries.

Chernobyl Three Mile Island Fukushima

WHAT HAPPENED?

Chernobyl Three Mile Island Fukushima

NUCLEAR DISASTER JIGSAW

THE LEFTOVERS• In addition to nuclear disasters, a major concern with

nuclear energy is what to do with the nuclear waste.Nuclear Waste Policy Act of 1982

• Federal law which established a comprehensive national program for the safe, permanent disposal of highly radioactive waste.

Which Current Disposal Method Makes the Most Sense??

Ground Level

Cavern

Mined Depositories

Deep Boreholes

YUCCA MOUNTAIN

WHY YUCCA?• It is in a desert location. • Isolated away from population centers. • Secured 1,000 feet under the surface. • In a closed hydrologic basin. • Surrounded by federal land. • Protected by natural geologic barriers. • Protected by engineered barriers and a flexible design.

State of Nevada has not been happy with the decision!• “By choosing Yucca mountain as the only option for a nuclear-waste facility,

Congress put the DOE in an untenable position. In effect, it sent the department out to prove that YuccaMountain would work as a repository rather than to do a dispassionate analysis of whether it could work or was the best possible site.”

CONCERNS ABOUT YUCCA

• Yucca’s location in an active seismic region. • The presence of numerous earthquake faults and volcanic cinder

cones. • There are at least 33 faults in and around the site.

• The presence of pathways (numerous interconnecting faults and fractures) that could move groundwater (and any escaping radioactive materials) rapidly through the site to the aquifer beneath and from there to the accessible environment.

• Evidence of hydrothermal activity within the proposed repository block.

Which Future Disposal Method Makes the Most Sense??