Nuclear Power PlantsNuclear Power Plants

There are over 500 worldwide that There are over 500 worldwide that produce 1/6 of the world’s power.produce 1/6 of the world’s power.

In the U.S. there are over 100 and they In the U.S. there are over 100 and they produce about 20% of our power.produce about 20% of our power.

Illinois has the largest number of power Illinois has the largest number of power plants than any other single state with 6.plants than any other single state with 6.

The Controlled Fission The Controlled Fission ReactionReaction

Elements of a Power PlantElements of a Power Plant

ElementElementContainment BuildingContainment Building

3 foot steel reinforced 3 foot steel reinforced concrete wallsconcrete walls

12 foot thick concrete 12 foot thick concrete foundationfoundation

FunctionFunction1.1. Protects public from Protects public from

internal problemsinternal problems

2.2. Protects from Protects from sabotagesabotage

3.3. Contains radiationContains radiation

Elements of a Power PlantElements of a Power Plant

ElementElementReactorReactor

Fuel rodsFuel rods - 12 foot - 12 foot long thin rods made of long thin rods made of fuel pellets made of fuel pellets made of 4% Uranium-235 (15 4% Uranium-235 (15 mill. in a reactor)mill. in a reactor)

FunctionFunction1.1. Provides the fuel Provides the fuel

that heats up the that heats up the moderator (water) moderator (water) into steam.into steam.

Elements of a Power PlantElements of a Power Plant

ElementElementReactorReactor

ModeratorModerator - in the - in the U.S. it is water. In U.S. it is water. In Russia it is graphite.Russia it is graphite.

FunctionFunction1.1. Slows down the Slows down the

neutrons.neutrons.

2.2. Shields against Shields against radiation.radiation.

3.3. Provides a cooling Provides a cooling effect to the fuel effect to the fuel rods.rods.

Elements of a Power PlantElements of a Power Plant

ElementElementReactorReactor

Control rodsControl rods - - cadmium (Cd) or cadmium (Cd) or Boron (B).Boron (B).

FunctionFunction1.1. Neutron “poisons.”Neutron “poisons.”

2.2. Absorbs neutrons.Absorbs neutrons.

Elements of a Power PlantElements of a Power Plant

ElementElementSteam GeneratorSteam Generator

Contains an isolated Contains an isolated water loop that has a water loop that has a heat exchanger (about heat exchanger (about 600 600 F and 1,000 psi).F and 1,000 psi).

FunctionFunction1.1. Heats up the water Heats up the water

to steam that turns to steam that turns the turbine, cools to the turbine, cools to water and then water and then reheats to steam.reheats to steam.

Elements of a Power PlantElements of a Power Plant

ElementElementThe TurbineThe Turbine

A large fan that turns A large fan that turns at 1,800 rpm.at 1,800 rpm.

Handles 15 million lbs Handles 15 million lbs of water per hour.of water per hour.

FunctionFunction1.1. Converts steam into Converts steam into

mechanical power mechanical power by the rotation of the by the rotation of the fan blades.fan blades.

Elements of a Power PlantElements of a Power Plant

ElementElementElectrical GeneratorElectrical Generator

Capable of 1.5 million Capable of 1.5 million horsepower.horsepower.

FunctionFunction1.1. Converts the Converts the

mechanical power of mechanical power of the rotating shaft to the rotating shaft to electrical power electrical power through the spinning through the spinning of wires in magnets.of wires in magnets.

Elements of a Power PlantElements of a Power Plant

ElementElementCondenserCondenser

Contains an isolated Contains an isolated water loop that has a water loop that has a heat exchanger that heat exchanger that removes heat.removes heat.

FunctionFunction1.1. Cools steam down Cools steam down

to 120 to 120 F so that it F so that it can recycle.can recycle.

Elements of a Power PlantElements of a Power Plant

ElementElementCooling LoopCooling Loop

Cooling lake or tower Cooling lake or tower (500 feet high) that (500 feet high) that cools 750,000 gallons cools 750,000 gallons per minute.per minute.

FunctionFunction1.1. Cools the cooling Cools the cooling

water so that the water so that the steam can continue steam can continue to be cooled.to be cooled.

Nuclear WasteNuclear Waste

Waste StorageWaste Storage Nuclear ReactorsNuclear Reactors

Each year 1/3 of the reactors fuel is changed.Each year 1/3 of the reactors fuel is changed. This equals about 30 tons per year per reactor.This equals about 30 tons per year per reactor. 100 reactors * 30 tons = 3,000 tons of spent fuel 100 reactors * 30 tons = 3,000 tons of spent fuel

per year that needs to be disposed of.per year that needs to be disposed of.

Military WasteMilitary Waste 3,000 tons of waste per year3,000 tons of waste per year Millions of tons of lower level wastesMillions of tons of lower level wastes

Nuclear WasteNuclear Waste

What do we do with all this waste that is What do we do with all this waste that is radioactive for thousands of years?radioactive for thousands of years? This waste is hot both temperature and This waste is hot both temperature and

radioactivity.radioactivity. CurrentlyCurrently

Must be cooled for 7-10 years.Must be cooled for 7-10 years. By law, it is stored on site in boronated water.By law, it is stored on site in boronated water.

Other possibilitiesOther possibilities Vitrify wastes and bury it deep in a mine.Vitrify wastes and bury it deep in a mine. Currently, Nevadan desert is a top prospect.Currently, Nevadan desert is a top prospect.

Nuclear WasteNuclear Waste

ROCK

MINE

ROCK

CONTAINERCONTAINER