(Jeffrey Mahn) USofA - Nuclear Energy Fables and Facts

NUCLEAR ENERGY FABLES AND FACTS Jeffrey A. Mahn Nuclear Engineer (Retired) Albuquerque, NM USA jamahn47@gmail.com

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Primary Areas of Disinformation • • • • •

Nuclear Power Plant Safety Radiation Exposure Environmental Effects Nuclear proliferation risk Radioactive Waste

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FABLE: Nuclear Power Plants Can Explode Like Nuclear Bombs • The nuclear fuel in U.S. nuclear power plants is lowenriched uranium, mostly non-fissioning U-238 atoms. Nuclear bombs use highly-enriched uranium, mostly fissioning U-235 atoms. • In a nuclear bomb, the U-235 or Pu-239 mass has to become extremely supercritical, so that all the atoms split at once, and not in sequence. This is achieved by design and happens in one microsecond.

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FABLE: Nuclear Power Plants Can Explode Like Nuclear Bombs • The neutron population in a nuclear reactor is controlled by using neutron absorbing materials to ensure that the atoms fission in sequence (i.e., in a controlled manner). • Even in a melted condition, nuclear reactor fuel cannot achieve a sustained supercritical configuration.

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Nuclear Weapon

3.50E+18

1.00E+19

3.00E+18

1.00E+18

Neutron Population

Neutron Population

Nuclear Weapon vs. Nuclear Reactor* 2.50E+18 2.00E+18 1.50E+18 1.00E+18 5.00E+17

1.00E+17 1.00E+16 1.00E+15 1.00E+14 1.00E+13 1.00E+12 1.00E+11

1.00E+10

1.00E+10

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

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0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

Microseconds

1.00E+11

Neutron Population

Neutron Population

3.00E+10

Prompt Critical Reactor

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Microseconds

2.50E+10

2.00E+10

1.50E+10

1.00E+10

1.00E+10

1.00E+09 10

20

30

40

50

60

Milliseconds

70

80

90

100

10

20

30

40

50

60

70

80

90

100

Milliseconds

* Neutron population plots are approximate representations for illustration purposes only 5

FABLE: All Nuclear Power Plants are Like Chernobyl • A power plant like Chernobyl could never be licensed to operate in the US or other Western countries.

– Chernobyl was a dual purpose reactor, designed to produce fuel for nuclear weapons as well as electricity.

– It had inherent design flaws that made it potentially susceptible to uncontrollable power excursions.

– It had no containment building enclosing the nuclear portion of the plant.

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FABLE: Nuclear Power Plants are a Radiation Health Hazard • Nuclear power plant radiation emissions are both regulated and extremely low.

• There is no epidemiological evidence that low dose/dose rate ionizing radiation adversely affects human health (or produces genetic defects).

• Despite failure of such consequences to materialize, the linear no-threshold (LNT) risk model persists to this day, helping to perpetuate low dose radiation phobia.

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Relative Radiation Risks • The sun – natural ionizing radiation risk (doesn’t evoke great fear) – causes 1.3 million skin cancer cases in U.S. each year† – causes 7,800 melanoma deaths in U.S. each year†

• Nuclear radiation – weaker carcinogen than most people think – caused only about 500 cancer cases among 90,000 survivors of atomic weapons in Hiroshima and Nagasaki who received high acute radiation doses† † RISK: A Practical Guide for Deciding What’s Really Safe and What’s Really Dangerous in the World Around You, David Ropeik, et al, Harvard Center for Risk Analysis

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Annual Risk of Death in the United States Hazard

Annual Individual Risk of Death

Heart Disease

1 in 300c

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Cancer

1 in 600c

2

4,000a,b,c

Risk Ranking

Motor vehicle accidents

1 in

Influenza

1 in 5,000e

4

Home accidents

1 in 9,000a

5

12,500e

3

Leukemia

1 in

Falls

1 in 13,000a,b,c

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Drowning

1 in 28,000a,b,c

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Fires

1 in 30,000a,b,c

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Suffocation by ingested objects

1 in 77,000c

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100,000b

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Air travel

1 in

11

Firearms

1 in 100,000a,b

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Poisoning by toxic gas or vapor

1 in 135,000a,c

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Electrocution

1 in

175,000a,b

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Receiving 10 mrem of radiation exposure

1 in 1,000,000d

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Tornadoes/Hurricanes

1 in 2,000,000b,c

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Lightning strike

1 in

2,000,000a,b,c

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Venomous bites and stings

1 in 5,000,000a,c,e

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Radiation release from nuclear power plant

1 in 10,000,000e

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Meteorite strike

1 in 100,000,000,000e

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FABLE: Any Amount of Radiation Exposure Will Cause Cancer • There is no epidemiological evidence that low dose/dose rate ionizing radiation causes cancer.

• Thousands of cancer deaths from the Chernobyl accident were predicted using the LNT radiation dose-response model. No radiation-induced increase in mortality has occurred.

• Thousands of cancer deaths from the Fukushima accident have also been predicted based on the LNT dose-response model. No one will die from what low radiation doses may have been incurred (see Note).

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LNT Collective Dose Concept Position statement of Health Physics Society* • A large dose to a small number of people is not equivalent to a small dose to many people, even if the collective doses are identical. • For populations estimated to receive a lifetime dose less than 100 mSv [10 rem] above background, a collective dose is a highly speculative and uncertain measure of risk and should not be used for estimating population health risks. * Radiation Risk in Perspective, Position Statement of the Health Physics Society; Adopted January 1996, Revised July 2010

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FABLE: Nuclear Power Plants are Bad for the Environment • “Renewable” energy plants require extremely large land areas to produce the same electrical power output as nuclear power plants.

• Life-cycle waste generation (per kWh of electricity produced) for nuclear power plants is either no more than or less than that of “renewable” energy plants.

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Land Requirements for Generating 1000 MW of Electricity Method for Generating Electricity Photovoltaic* Wind*

Land Area (sq. miles) 22 – 80a 520 – 1160b

Hydroelectric

1500c,e

Biomass

2600d,e

Nuclear

1.5

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Life-Cycle “Waste” Comparisons • Only considering annual waste production from electrical-generating system operation results in an incorrect understanding of “waste” generation.

• The true picture of “waste” generation must be based on system life-cycle comparisons.

• Renewable energy systems are not as “benign” as some claim: – Millions of pounds of polluted sludge and contaminated water are annual byproducts of solar panel manufacturing.

– Wind turbine generators are manufactured with rare-earth metals, the mining and processing of which creates millions of tons of toxic waste.

– Roads and pads developed for ultimate placement of wind turbines affect the environment.

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Comparison of Life-Cycle CO2 Emissions Tons of Carbon Dioxide Equivalent per Gigawatt-Hour 1,041

622

Coal

Natural Gas

46

39

18

17

15

14

Biomass

Solar PV

Hydro

Nuclear

Geothermal

Wind

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Emissions Produced by 1 Kilowatt-hour of Electricity Based on Life-Cycle Analysis Generation Option

Greenhouse gas emissions (in gram equiv.

CO2/kWh)

Sulfur dioxide emissions (in milligrams/kWh)

Nitrogen oxide emissions (in milligrams/kWh)

Particulate matter (in milligrams /kWh)

Hydropower

2 – 48

5 – 60

3 – 42

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Nuclear

2 – 59

3 – 50

2 – 100

2

Wind

7 – 124

21 – 87

14 – 50

5 – 35

Solar photovoltaic

13 – 731

24 – 490

16 – 340

12 – 190

Biomass forestry waste combustion

15 – 101

12 – 140

701 – 1,950

217 – 320

Natural gas (combined cycle)

389 – 511

4 – 15,000[*]

13 – 1,500

1 – 10

790 – 1,182

700 – 32,321

700 – 5,273

30 – 663

Coal – modern plant

[*] The sulfur content of natural gas when it comes out of the ground can have a wide range of values. When the hydrogen sulfide content is more that 1 percent, the gas is usually known as “sour gas.” Normally, almost all of the sulfur is removed from the gas and sequestered as solid sulfur before the gas is used to generate electricity. Only in the exceptional case when the hydrogen sulfide is burned would the high values of sulfur dioxide emissions occur.

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FABLE: Nuclear Fuel Reprocessing Will Lead to Proliferation of Nuclear Weapons • The plutonium in used nuclear reactor fuel is not suited for use in nuclear weapons. • Used nuclear fuel has been reprocessed outside the U.S. for decades and nuclear proliferation has not been a significant issue.

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Why Pu from Nuclear Fuel Reprocessing is not Suitable for Nuclear Weapons • A normal light-water reactor fuel cycle generates too much Pu-240 (>18% of used nuclear fuel plutonium content) for use in a nuclear weapon (which requires >93% Pu-239, or <7% Pu-240).

• To make reactor-grade plutonium into weapon-grade plutonium is impractical.

– There is no known gaseous form of Pu at reasonable temperatures, making physical separation of the Pu isotopes extremely difficult.

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Why Pu from Nuclear Fuel Reprocessing is not Suitable for Nuclear Weapons • To make reactor-grade plutonium into weapon-grade plutonium is dangerous.

– Pu-240 has a fairly high spontaneous fission rate, making it a fairly strong neutron emitter. Neutron radiation is more biologically harmful than gamma-ray radiation.

– Pu-241 decays to Am-241, a strong alpha emitter that poses self-heating problems and radiotoxicity problems if inhaled or ingested.

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World Commercial Reprocessing Capacity (tonnes U per year)

LWR Fuel

France, La Hague (1967)

1600

UK, Sellafield (THORP - 1990)

1200

Russia, Ozersk (Mayak - 1978)

400

Japan (Rokkasho - 1977)

800

Total LWR (approx) Other Nuclear Fuels

4000

UK, Sellafield (Magnox - 1964)

1500

India (PHWR, 4 plants - 1982)

300

Total other (approx)

1800

Total Commercial Capacity

5800

Dates are facility commissioning dates Source: European Nuclear Society, July 29, 2008

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FABLE: Nuclear Waste Cannot be Handled or Stored Safely • Used nuclear power plant fuel is being safely located and monitored at nuclear plant sites in dry-storage casks.

• Only 4% of used nuclear fuel (containing 95% of the radioactive content) is characterized as high-level waste following reprocessing.

• Long-term storage of high-level waste from nuclear fuel reprocessing is neither a technological nor safety problem.

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Connecticut Yankee (decommissioned) • This is the entire fuel used during the 30 years of this reactor’s operation.

• The waste volume could be reduced even more by reprocessing.

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Total Nuclear Waste Characterization

High level waste is used nuclear fuel that has been in the reactor core producing heat to generate electricity for 3 to 4.5 years.

Intermediate level waste includes such things as used filters, steel components from within the reactor, and some effluents from reactor coolant cleanup operations.

Low level waste consists of lightly-contaminated items like tools and work clothing from power plant operations.

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Used Nuclear Fuel is Not All Waste Spent Fuel Material

Material Disposition

Reprocessed plutonium and Fission in thermal, fast, or uranium sub-critical reactors Fuel cladding, filters

Less stringent storage as intermediate-level waste

Long-lived fission and activation products

Nuclear transmutation or geological repository

Medium-lived fission products Cs-137 and Sr-90

Medium-term storage as high-level waste

Useful radionuclides and noble metals

Industrial and medical uses

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FABLE: Electricity from Nuclear Power Plants can be Replaced by Renewable Energy Sources â&#x20AC;˘ Nuclear power plants provide base-load electricity (24 hours a day, 365 days a year). â&#x20AC;˘ Solar energy and wind energy cannot replace baseload electricity. They can only supplement it.

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Contact Information Jeffrey A. Mahn Nuclear Engineer (Retired) Albuquerque, NM USA jamahn47@gmail.com

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