MICHAEL OLIVER AND DIANA OLSEN Nuclear Power. Personal Background 6 months Navy Nuclear Field...
-
Upload
milo-foxen -
Category
Documents
-
view
216 -
download
1
Transcript of MICHAEL OLIVER AND DIANA OLSEN Nuclear Power. Personal Background 6 months Navy Nuclear Field...
MICHAEL OLIVER AND DIANA OLSEN
Nuclear Power
Personal Background
6 months Navy Nuclear Field ‘A’ school6 months Navy Nuclear Power School6 months Nuclear Field Prototype School4 years on board the USS Nimitz/USS
Enterprise as a Reactor Operator
Fission
1938 Hahn and Strassman fired neutrons from the elements radium and beryllium into uranium.
The sums of the fission products’ masses did not equal uranium’s atomic mass.
Uranium underwent fission, converting some its mass to energy, thus proving Einstein’s theory.
General History
Fission Graphically
First Reactors
December 2, 1942 Chicago Pile became the first self-sustaining chain-reaction.
Relatively small, total output power was 200W
First reactors built so quick because it was during World War II
General History
After the War
1946 Atomic Energy Commission (AEC) was created
Energy Act of 1954, first steps towards commercial use of nuclear power
Energy Reorganization Act of 1974, replaced the AEC with the Nuclear Regulatory Commission
NRC responsibilities include licensing operators and plants
General History
Reactor Licensing Process
Radiation
“Radiation consists of several types of subatomic particles, called gamma rays, neutrons, electrons and so on, that shoot through space at very high speeds, something like 100,000 miles per second”
They can penetrate your skin, cause biological damage to our cells, potentially resulting in cancer or genetic defects.
Getting exposed to radiation
Radiation
The average person is struck with about 15,000 of these subatomic particles daily from natural sources
Probability that one of these subatomic particles will actually cause cancer is 1 in 50 million billion.
NRC Regulations
Rem—amount of ionizing radiation required to produce the same biological effect as one rad of high penetration x-rays
5,000 mrem/year to the whole body50,000 mrem/year to an organ, the skin, or
extremity15,000 mrem/year to the lens of an eye500 mrem/year to a pregnant woman100mrem/year to the general public
Perspective
Chest radiograph – 3.2 mremX-rays from TV set 1” away - 0.5mrem/hourAirplane ride at 39,000 ft. 0.500mrem/hourNatural Gas in your home 9mrem/yearIf you actually work in the power plant
0.6mrem/yearAverage dose from nuclear power plant less
than 0.1mrem/yearAverage dose from coal fire power plant
0.165mrem/year
Relative Radiation Dosage
Radiation Sickness
Earliest onset is 75,000 mremGenetic defects occur at 100,000 mremExpected death without medial treatment
occurs at 400,000 mrem
Deaths by TW
http://nextbigfuture.com/2011/03/deaths-per-twh-by-energy-source.htmlEnergy Source Death Rate (deaths per TWh) • Coal electricity – world avg 60
(26% of world energy, 50% of electricity) • Coal (elect,heat,cook)– China 170 • Coal electricity- China 90 • Coal – USA 15 • Oil 36
• (36% of world energy) • Natural Gas 4
• (21% of world energy) • Biofuel/Biomass 12 • Peat 12 • Solar (rooftop) 0.44
• (0.2% of world energy for all solar) • Wind 0.15
• (1.6% of world energy) • Hydro 0.10
• (Europe death rate, 2.2% of world energy) • Hydro - world including Banqiao) 1.4
• (about 2500 TWh/yr and 171,000 Banqiao dead) • Nuclear 0.04
• (5.9% of world energy)
Pressurized Water Reactors
Maintains water in liquid state by high pressure Water is heated in the reactor vessel RCPs pump hot water through S/G, which heats
secondary water supply Secondary water boils, producing steam Steam drives the turbines Turbines drive the generator which produces
electricity
Pressurized Nuclear Reactor Plant
Boiling water reactors
Water boils directly in the reactor vessel Steam is carried through pipes directly to the turbine Which drives the generator Which produces electricity
Boiling Water Reactor Plant
Reactor Pressure Vessel
• Fuel - Uranium 235 and Uranium 238Water – acts as a coolant, moderator, and
heat transfer agentControl rod drive mechanisms – used to
maintain level of desired reactivity
Containment Building
Purpose: Prevent the release of fission products to the general public 45” of steel-reinforced concrete 2.5” of steel reinforcement rods 36” of concrete shielding 8” of steel for the reactor vessel ¼” steel linder
Molten Fluoride Salt Thorium Reactor
* * * Design in Progress * * *
Molten Fluoride Salt Thorium Reactor
Wouldn’t have potential of core meltdown: plug in
bottom of core would allow for salt to drainAble to operate at
lower pressures wouldn’t need
very thick concrete containment vesselMore advantages: check out TED talk video
Three Mile Island
March 28, 1979, accident started with the failure of the cooling system
“Within two minutes after the start of the accident the steam generators boiled dry, because they had no feed water source and there was a substantial heat output from the reactor core due to radioactive decay”
Misconceptions
Myth: The accident would result in a large release of radioactive material
Fact: The accident was over exaggerated and there was relatively little, to no, actual damage to the reactor
Reality
The average exposure to the general public was 1.2 mrem.
After the initial clean up of TMI-2 reactor many were surprised the pressure vessel itself withstood the molten fuel on the bottom
Accident has no associated deaths, or significant injuries
Greenhouse Gas Problem
In 2011 nuclear generated electricity prevented the release of 613 million metric tons of carbon dioxide
Equivalent to taking 118 million cars of the roads
Possible because nuclear power does not burn anything
Waste
Dr. Bernard Cohen:“ The Nuclear waste is 5 million times smaller by weight and billions of times smaller by volume [ than coal-burning waste]. The nuclear waste from one year of operation weighs about 1.5 tons and would occupy a volume of half a cubic yard, which means it would fit under an ordinary card table with lots of room to spare. Since the quantity is so small it can be handled with a care and sophistication that is completely out of the question for the millions of tons of waste spewed out annually from our analogous coal-burning plants. [Also,] if all the air pollution emitted from a coal plant in one day were inhaled by people 1.5 million people could die from it, which is 10 times the number that could be killed by ingesting or inhaling the waste produced in one day by a nuclear power plant.”
Waste
2,000 metric tons annuallySecurely managed on site in used fuel pools, lined
with steelAfter cooling, are put in dry casksFuel rods replaced every 15-18 months, so overtime
have the issue of spaceGeneral consensus, safest way to dispose of nuclear
wastes is in a specialized facility 1,650 feet below the ground.
1.7 million miles, over 3,000 shipments, in the past 40 years, with no harmful radiation effects to general public or environment
Future
D.O.E believes the U.S will need an additional 250,000 MW of electric generation capacity by 2035
Nuclear power has lower production cost than their analogous coal or natural gas plants
Overall lower production costsTechnological advances and a better
understanding of reactor power has improved nuclear power plant efficiency since 1990, raising total electricity output by an amount equal to building 28 new reactors