nuclear energy ari mcguirk, ayad muhammad, jessica scarbrough

Nuclear EnergyAri McGuirk, Ayad Muhammad, Jessica Scarbrough

Overview• History

• Electricity Generation

• Reactor Types

• Environmental Implications

• Economic Implications

• Political Repercussions

• Conclusion

Pre WWII• Research fueled by German,

Russian and British efforts to achieve self-sustaining fission reaction.

• 1939- conceptualization of critical mass by Francis Perrin.

• USSR- established ten physics institutes, purged by Stalin.

• Germany’s subsequent invasion of Soviet Union forced USSR to consider nuclear energy for military applications.

British Progression WWII provided necessary

impetus for progress.

Frisch-Peierls Memorandum- experimental proof that chain reaction was possible.

Churchill wanted weaponization ASAP.

U.S. uninvolved until December 7, 1941

Manhattan Project Production plants,

process development, nuclear facility designs underway immediately after Pearl harbor.

1942- First man-made, controlled nuclear chain reaction at University of Chicago.

1945- Hiroshima and Nagasaki, end of WWII.

Post WWII Nuclear energy used for

electricity generation.

Cold war spurred new technologies.

1951- Experimental Breeder Reactor, first to produce measurable amount of electricity in Idaho.

1953- Eisenhower’s “Atoms for Peace”

ModernityHuge advancements in 50’s and 60’s.

By 1964, US, Canada, France, USSR among nations with operational nuclear reactors.

Decline during 70’s until 2000’s.

Climate change reinvigorating subject.

Several Asian countries spurring their nuclear programs- China, India, S. Korea.

Energy GenerationTwo ways of generating nuclear energy:

Nuclear fusion

Energy GenerationExamples of nuclear fusion:

• Fusion is an unstable process that requires a tremendous amount of energy

• Currently no commercial reactor that generates electricity from fusion.

• Sun generates 3.86 x 10^26 watts per second

Energy GenerationNuclear fission

Energy GenerationNuclear fission is used in modern commercial

nuclear power plants.

Inside the Nuclear Reactor• Uranium, a naturally

occurring radioactive element, is the primary fuel, particularly the isotope U-235.

• Atoms of U-235 are bombarded with neutrons to split and release heat in the presence of a moderator (usually water) to control reaction.

• The heat makes water steam and drive a turbine to generate electricity.

Nuclear Reactor Types

Two main types:

Water moderated

Heavy-water

Light-water

Pressurized water reactor

Most common type

Boiling Water reactor

Graphite moderated

Gas-cooled

Water-cooled

Light-water graphite-

moderated reactor

Pressurized Water Reactor

Other type of reactors:

Differences: Water vs. Graphite

moderated The moderators slow down

the neutrons allowing them to sustain a nuclear chain reaction

Reaction occurs when a slow neutron hits an atom and the atom quickly expels another neutron

75% of world’s reactors us light-water

20% use graphite

5% use heavy-water

Water vs. Gas coolant

These are used to

prevent the reactor from

over heating.

The water or gas

transfers heat away from

the core of the reactor

Most common coolant is

light-water

World Over-view of Reactor TypesNuclear power plants in commercial operation Reactor type Main Countries Number GWe Fuel Coolant Moderator

Pressurised Water Reactor (PWR)

US, France, Japan, Russia, China

273 253 enriched UO2

water water

Boiling Water Reactor (BWR) US, Japan, Sweden 81 76 enriched UO2

water water

Pressurised Heavy Water Reactor 'CANDU' (PHWR)

Canada 48 24 natural UO2 heavy water

heavy water

Gas-cooled Reactor (AGR & Magnox)

UK 15 8

natural U (metal), enriched UO2

CO2 graphite

Light Water Graphite Reactor (RBMK & EGP)

Russia 11 + 4 10.2 enriched UO2

water graphite

Fast Neutron Reactor (FBR) Russia 2 0.6 PuO2 and UO2

liquid sodium

none

TOTAL 434 372

Environmental Impacts

• No CO2 emissions

• Small land area

• Efficiency between 33-

45%

Environmental Impacts cont.

• Requires fossil fuels to

mine and transport

uranium

• Needs water

• Nuclear Waste concerns

• Accidents are deadly

Economic Implications Nuclear Energy is ~35% efficient with

a capacity factor of ~90%.

Very high capital costs $4540/kW compared to $3500/kW

for coal. Labor intensive, time consuming

and high construction costs.

Very low operating Costs Uranium is cheap and abundant.

Fuel costs do not affect price much, which means electricity is cheap.

Fuel can be reused.

Ambivalent external costs Carbon emissions are very low. Accidents are rare but very

destructive. Improper disposal of waste may

have serious social implications.

Political ImplicationsWho is allowed to retain nuclear warheads?

Who is allowed to utilize nuclear energy for electricity generation?

Who establishes policy over a nation’s nuclear program?

Why?

Warheads vs ElectricityWarheads Electricity (2012)

France- 75%

Slovakia- 54%

Belgium- 51%

Ukraine- 46%

Hungary 46%

Sweden- 38%

Slovenia- 36%

France Scheduled to reduce to

50% by 2025.

Largest net exporter of electricity due to low cost of generation.

17% of their electricity is from recycled nuclear fuel.

Building first Gen. III reactor.

58 reactors supplying 416 kWh in 2014.

Iran Located in oil laden

Middle East.

Possesses single nuclear reactor.

Possesses zero nuclear weapons.

Subject to sanctions designed to deter their nuclear weapons program.

Sanctions Imposed on Iran by U.N. Security Council

Block the transfer of weapons, components, technology and dual use items to Iran’s prohibited nuclear and missile programs.

Target select sectors of the Iranian economy relevant to its proliferation activities.

Induce Iran to engage constructively, through discussions with the United States, China, France, Germany, the UK, and Russia (Department of State).[

U.S. RelationsFrance

Long standing ally of the United States.

Allowed to retain 300 nuclear warheads.

Largest net exporter of electricity in the world.

Iran

Sour relations with U.S. after unsuccessful coup, subsequent revolution in 1979.

Zero nuclear warheads; one reactor.

Engaged in ongoing talks designed to restructure their program.

Conclusion Nuclear power historically relevant, from weaponization to

modern energy generation.

Produces cheap energy, but requires tremendous investment of various resources.

Moderate efficiency; theoretically the new designs will be more efficient.

Low in carbon emissions, but may aversely affect surrounding ecosystem; uses fossil fuels for uranium mining.

No permanent waste storage facility in U.S.

Polarizing in the politics of nations- requires tremendous cooperation from world leaders.