Introduction to Nuclear Introduction to Nuclear PowerPower

Kenneth M. Klemow, Ph.D.For BIO / EES 105 at Wilkes University

What is nuclear power?What is nuclear power?Ability to harness energy from

atomic nuclei for consumptive uses◦Mostly electrical generation

Two kinds of nuclear energy◦Fission◦Fusion

Nuclear fissionNuclear fissionHeavy atoms split, producing

smaller particles, electromagnetic radiation, and energy.

Most common form of nuclear fission involves splitting of certain forms of Uranium

UraniumUraniumActinide metal with atomic number of

92.◦Thus 92 nuclei in nucleus

Various isotopes (based on # neutrons)◦U-233: 141 neutrons◦U-234: 142 neutrons◦U-235: 143 neutrons◦U-236: 144 neutrons◦U-237: 145 neutrons◦U-238: 146 neutrons

Used in nuclear power

Most common in nature

Uranium rockUranium rock

Fission of U-235Fission of U-235

Reaction yields heatReaction yields heatTransferred to fluid surrounding

coresFluid heats up, forming steamSteam drives turbines, creating

electricity

Uranium needs to be Uranium needs to be enrichedenrichedMost uranium in

form of U-238U-235 concentration

increasedEnrichment typically

involves removal of other isotopes

Commonly done by centrifugation, though highly secret.

Nuclear cycleNuclear cycle

Nuclear reactor overviewNuclear reactor overview

http://www.bbc.co.uk/

Nuclear fuel in form of Nuclear fuel in form of rodsrods

http://coto2.wordpress.com

NucleaNuclear r reactorreactor

http://www.bbc.co.uk/

HistoryHistoryBasis in 1930s

◦Atomic nuclei contain vast energy1940s

◦Research on nuclear energy wrapped into Manhattan Project – atomic bomb

Early 1950s◦US, Canada, USSR began work on

generating electricity via nuclear energy

◦USSR builds nuclear reactor to feed into power grid.

History IIHistory IILate 1950s

◦Nuclear plants constructed in Pennsylvania and Virginia, Idaho, and USSR

1960-1980◦Nuclear capacity increased greatly in US,

Europe, USSR.1980s and after

◦Nuclear construction slowed due to rising anti-nuclear sentiment, costs involved in meeting more stringent standards

Worldwide nuclear powerWorldwide nuclear power

http://www.maximizingprogress.org/2008/01/world-energy-activity.html

Worldwide: 443 reactors in 32 countries (<25 under construction)

Nuclear production - Nuclear production - WorldwideWorldwide

Top nuclear countriesTop nuclear countries

http://utopianist.com

Nuclear power in USNuclear power in US

Nuclear power plants in USNuclear power plants in US

http://abhsscience.wikispaces.com/A+Block+-+Uranium

103 reactors in 31 statesNo new construction since 1974Pa has the 2nd largest capacityIllinois is 1st

Trend of nuclear Trend of nuclear production production

Risks associated with nuclear Risks associated with nuclear powerpowerMainly due to radiation releases –

human health◦Small releases during routine

operation◦Accidents◦Waste disposal

Thermal pollution

Radiation risks - generalRadiation risks - generalRadiation can cause cancer (1%

of all causes)Radiation all around us

◦15,000 “hits” / second◦Chance of any one hit causing cancer:

1/30,000,000,000,000,000

http://www.who.int/ionizing_radiation/env/en/

Increased risk by nuclear Increased risk by nuclear powerpowerRepresents 0.2% of increased

exposureThus 0.002% increased cancer

rate◦Reduces life expectancy by one hour◦Risks from other fossil fuel sources:

3-40 days

AccidentsAccidentsMain concern of accident: damage to

reactor leading to “meltdown”Nuclear plants built to reduce risk of

accidents◦ Reactor shielded by steel and concrete

Predicted loss of life by probability analysis◦ Chance of meltdown estimated to be 1/20,000

years of operation◦ Loss of life in 1/3 accidents◦ Average # deaths 400 / meltdown

Compare to coal burning◦ 10,000 deaths / year◦ Thus would need 25 meltdowns / year to equal

risk from coal

Cohen, B. http://www.physics.isu.edu/radinf/np-risk.htm

Three major accidents in Three major accidents in pastpast

Chernobyl – Ukraine•April 1986•>350,000 evacuated•64 died•Toll could reach 4000

Fukushima - Japan•March 2011•>300,000 evacuated•No deaths•Toll could reach 130

Three Mile Island - PA•March 1979•>140,000 evacuated•No deaths•No incidence of cancer

Radioactive wasteRadioactive wasteSpent rods converted into rock-like

material and buried deep undergroundOther material buried into soilsSome U-235 can be recycled

https://sites.google.com/site/nuclearenergyinjapan/home/possible-solutions

A 1000 MW(e) Nuclear Plant would A 1000 MW(e) Nuclear Plant would have the same effect as:have the same effect as:

Land: Disturbed Land 100 MW (e) coal

Land: Overburden moved

95 MW(e) coal

Fossil fuel used: 45 MW(e) coal

Effluents: SOx, NOx, Hydrocarbons, CO

45 MW (e) coal

Eventual # of deaths caused by the wastes Eventual # of deaths caused by the wastes from 1000 MWe-Y electrical power from 1000 MWe-Y electrical power generationgeneration

Nuclear High level wastes 0.018

Low level wastes 0.0004

Routine emissions 0.3

Coal Air pollution 75

Radon emission 30

Chemical cacrcinogens

70

Loss of life expectancy (LLE) due Loss of life expectancy (LLE) due to various risks in the U.S.to various risks in the U.S.

ACTIVITY LLE (Days)

Living in poverty 3500

Smoking 2300

Unmarried 2000

Coal Miner 1100

30 lbs overweight 900

Small car vs. midsize 60

Living very near a NPP 0.4

Nuclear energy - Nuclear energy - advantagesadvantagesVery high energy densityNot a fossil fuel – no greenhouse

gas emissionsReliable

Nuclear energy - Nuclear energy - disadvantagesdisadvantagesConcerns over radiation in event

of accidentsWaste disposal an issueLong lead time for plant

constructionHabitat fragmentation where

uranium mined