Uranium Ore - must be “enriched”

most abundant = 238U

fissionable = 235U (“fuel”)

Reminder: Isotopes different # of neutrons

Naturally occurring radioactive isotopes

(alpha decay, beta decay, spontaneous fission)

In uranium ore some 238U is removed and 235U is increased from 0.7% that occurs naturally to almost 3%.

Wikimedia Commons."

Nuclear Fission = neutrons split the nuclei of atoms such as uranium-235 & plutonium-239 and release energy mostly as high temperature heat which is used to produce high pressure steam to spin turbines to generate electricity.

The dome-shaped containment building at the Shearon Harris Nuclear Power Plant near Raleigh, NC

Light Water Reactors - Pressurized vs. Boiling Water Reactor

Control Rods - made of neutron absorbing material (cadmium/boron) moved in and out of the spaces between the fuel. REGULATES rate of fission.Moderator - slows down the neutrons to keep chain reaction going. Material can be water (75%) graphite, or heavy water (deuterium oxide)

Coolant - usually water circulates through the reactors to keep materials from melting and to produce steam for the turbines to

produce electricity

Core – contains 35,000-70,000

fuel rods packed with

“pellets” that equal the

energy out put of 1ton of coal

ADVANTAGESLarge Supply

Low Environmental ImpactEmits only 1/6 of CO2 as coal

Moderate land and water disruption (without accidents)

DISADVANTAGESHigh Cost – even with Govt. subsidies

Low net energy yield (facilities $$)Major Accidents are HIGH environmental

costWaste Solutions??

Encourages Technology for Weapons Use

CHERNOBYL 1986 – Ukraine

125,000 died from exposure 3.5 million have become ill

Cost = $358 million Flaws in designs & operator

errors

THREE MILE ISLAND 1979

Pennsylvania Operator Error