Chapter 12
Nuclear Energy
“We cannot build more power plants
without realizing that they impinge on our
freshwater supplies. And we cannot
build more water delivery and cleaning
facilities without driving up energy
demand.”
http://www.scientificamerican.com/article.cfm?id=the-future-of-fuel
Hanford Site
1) Generating Electricity with Nuclear Energy
2) Nuclear Energy Lite
 Isotopes, Radioactive Decay & Half
Lives
3) Nuclear Fission & Nuclear Fuel
 Fissionable vs Fissile
4) Benefits & Problems of Nuclear Energy
 Spent Fuel & High-Level Waste (HLW)
5) Safety Issues at Power Plants
 Meltdowns & Accidents (Three Mile
Island, Chernobyl & Fukushima Daiichi)
6) Turkey Point Expansion
Water & Electricity Production
Figure
12.16
Turkey Point Cooling Canals
1) Generating Electricity with Nuclear Energy
2) Nuclear Energy Lite

Isotopes, Radioactive Decay & Half Lives
3) Nuclear Fission & Nuclear Fuel

Fissionable vs Fissile
4) Benefits & Problems of Nuclear Energy

Spent Fuel & High-Level Waste (HLW)
5) Safety Issues at Power Plants
 Meltdowns & Accidents (Three Mile
Island, Chernobyl & Fukushima Daiichi)
6) Turkey Point Expansion
Nuclear Energy Lite
 Nuclear fission
• Splitting of an atomic nucleus into two
smaller fragments, accompanied by the
release of a large amount of energy
 Nuclear fusion
• Joining of two lightweight atomic nuclei
into a single, heavier nucleus,
accompanied by the release of a large
amount of energy
Atoms and Radioactivity
 Nucleus
• Comprised of
protons (+) and
neutrons (neutral)
 Electrons (-) orbit
around nucleus
 Neutral atoms
• Same # of protons
and electrons
Atoms and Radioactivity
 Mass number
• Sum of the protons and neutrons in an
atom’s nucleus
 Atomic number
• Is the number of protons within the
nucleus
• An element is defined by the number of
protons in its nuclei. Therefore, each
element has its own atomic number.
Atoms and Radioactivity
 Mass number
 Atomic number
 Isotope
• Atoms of a given element may have a
different number of neutrons
• Each variant is called an isotope, and each
isotope has a different mass number but
the same atomic number.
 Radioactivity
• Emission of energetic particles or rays
from unstable atomic nuclei (radiation)
Radioactive Decay
 Radioactive Decay
• The spontaneous emission of radiation
leading to the transmutation of one
element into another.
• For example, the unstable (radioactive)
isotope of uranium known as U-235 over
time will spontaneously decay into lead
(Pb-207).
 The decay of a given isotope is described
by that isotope’s half-life.
Twizzler Decay
18
Length of Twizzler (cm)
16
14
12
10
8
6
4
2
0
0
1
2
3
Number of Half Lives
4
5
Radioactive Isotope Half-lives
Table
12.3
1) Generating Electricity with Nuclear Energy
2) Nuclear Energy Lite

Isotopes, Radioactive Decay & Half Lives
3) Nuclear Fission & Nuclear Fuel

Fissionable vs Fissile
4) Benefits & Problems of Nuclear Energy

Spent Fuel & High-Level Waste (HLW)
5) Safety Issues at Power Plants
 Meltdowns & Accidents (Three Mile
Island, Chernobyl & Fukushima Daiichi)
6) Turkey Point
1) Generating Electricity with Nuclear Energy
2) Nuclear Energy Lite
 Isotopes, Radioactive Decay & Half Lives
3) Nuclear Fission & Nuclear Fuel
 Fissionable vs Fissile
4) Benefits & Problems of Nuclear Energy
 Spent Fuel & High-Level Waste (HLW)
5) Safety Issues at Power Plants
 Meltdowns & Accidents (Three Mile
Island, Chernobyl & Fukushima Daiichi)
6) Turkey Point Expansion
Fissionable vs. Fissile
 Fissionable
• A fissionable material is one whose
atoms can split into smaller parts. It is the
nucleus that fissions producing two
nuclei that are not of the same element as
the original atom.
 Fissile
• A fissile material is one that is capable of
sustaining a chain reaction of nuclear
fission. Nuclear fuels must be fissile.
U-235 & U-238 are both fissionable, but
only U-235 is also fissile.
1) U-235 is
bombarded with
neutrons.
2) The nucleus
absorbs
neutrons.
3) It becomes
unstable and
splits into 2
nuclei with 2-3
neutrons also
emitted.
4) Newly emitted
neutrons
bombard other
U-235 atoms.
5) Chain reaction
Fission Chain Reaction
Figure
12.15
Enriched, Reactor &
Weapons Grade
Uranium
1) Generating Electricity with Nuclear Energy
2) Nuclear Energy Lite
 Isotopes, Radioactive Decay & Half Lives
3) Nuclear Fission & Nuclear Fuel
 Fissionable vs Fissile
4) Benefits & Problems of Nuclear Energy
 Spent Fuel & High-Level Waste (HLW)
5) Safety Issues at Power Plants
 Meltdowns & Accidents (Three Mile
Island, Chernobyl & Fukushima Daiichi)
6) Turkey Point Expansion
Benefits & Problems of Nuclear Energy
Benefits
 Less of an immediate environmental
impact compared to fossil fuels
• No acid precipitation formed. (Acid
precipitation results from
atmospheric chemistry between
sulfur & nitrogen containing
compounds & water vapor.)
 Carbon-free source of electricity.
• No greenhouse gases emitted.
http://www.wired.com/2016/04/nuclear-power-safe-save-world-climate-change/
Benefits & Problems of Nuclear Energy
Problems
 20% of US electricity is from nuclear

energy, but it is only affordable because
of generous government subsidies.
The reactor design most commonly used
requires an immense amount of fresh
water for cooling.
• One megawatt of power requires
25,000-60,000 gallons of water (as
much as 8x more than natural gas)
Benefits & Problems of Nuclear Energy
Problems
 It is expensive to build nuclear plants,
which means a long cost-recovery time.
 Fixing technical and safety issues in
existing plants also is expensive. The
Crystal River plant in Florida was
closed in 2009 because of nearly $1
billion in accidental damages incurred
during maintenance.
Spent Fuel & High-Level Nuclear Wastes
Problems
 Spent nuclear fuel is fuel removed from a
reactor because the concentration of
fissile material no longer efficiently
promotes the fission chain reaction. The
spent fuel contains high-level radioactive
waste (HLW), i.e., fission products
generated in the reactor core (such as
plutonium-239) that will remain hazardous
for hundreds of thousands of years.
Solid and liquid
wastes in
barrels were
buried in pits,
or unlined
landfills.
Tanks with high- & lowlevel wastes have leaked,
releasing about 1 million
gallons.
Some waste disposed
of directly on to the
soil.
water Receptors
table
River
aquifer
Liquid contaminants
were pumped directly
into the soil.
Cooling & waste water
was directed to storage
ponds.
High-Level Radioactive Waste
 On-site storage solutions
• Wastes are stored at the nuclear plant
facility where they are generated.
• Under water storage (as at Fukushima)
• Above ground concrete and steel casks.
Figure 12.19
Spent Nuclear Fuel Storage Sites
http://www.yuccamountain.org/faq.htm
Nuclear Weapons & Weaponized
Waste
 More than 30 countries use nuclear
energy to create electricity.
 Each of these countries have access to
spent fuel needed to make nuclear
weapons.
 Terrorist organizations will not have the
ability to make a bomb, but may be
inclined to use the spent fuel to make
so-called “dirty bombs”.
Dirty Bombs
1) Generating Electricity with Nuclear Energy
2) Nuclear Energy Lite
 Isotopes, Radioactive Decay & Half Lives
3) Nuclear Fission & Nuclear Fuel
 Fissionable vs Fissile
4) Benefits & Problems of Nuclear Energy
 Spent Fuel & High-Level Waste (HLW)
5) Safety Issues at Power Plants
 Meltdowns & Accidents (Three Mile
Island, Chernobyl & Fukushima Daiichi)
6) Turkey Point Expansion
Safety Issues in Nuclear Power Plants
 Reactor Core Meltdown
• At high temperatures the metal
encasing the uranium fuel can melt,
releasing radiation.
 Meltdown probability is low (thankfully)
 Sites of major accidents:
• Three Mile Island, PA (1979)
• Chernobyl, Ukraine (1986)
• Fukushima Daiichi, Japan (2011)
Three-Mile Island
Three-Mile Island
 1979 – most serious reactor accident in the
U.S.
 50% meltdown of one reactor core.
• Containment building kept most radiation
from escaping (as it was designed to do).
• No environmental damage or casualties
 Public apprehension of nuclear energy
spiked. Furthermore, the accident led to
the cancellation of many new plants, and a
decades-long hiatus in new license
applications to the NRC.
Chernobyl
 1986- Remains the single
worst accident in history.
 1 or 2 steam explosions
destroyed the nuclear
reactor vessel.
• No containment
building.
• Large amounts of
radiation escaped into
atmosphere due to
graphite fire.
Chernobyl
 Radiation
spread was
unpredictable.
 Death toll
estimates
range from
4,000-100,000.
The larger
figure
includes eventual
cancer deaths.
Figure 12.17
Chernobyl
Chernobyl Tourism
Fukushima Daiichi
http://www.popsci.com/science/article/2011-10/fukushima-fallout-was-worse-official-estimates-claimed-new-study-says
Fukushima Daiichi Reactor Design
Fukushima Daiichi
http://www.popsci.com/science/article/2011-10/fukushima-fallout-was-worse-official-estimates-claimed-new-study-says
1) Generating Electricity with Nuclear Energy
2) Nuclear Energy Lite
 Isotopes, Radioactive Decay & Half Lives
3) Nuclear Fission & Nuclear Fuel
 Fissionable vs Fissile
4) Benefits & Problems of Nuclear Energy
 Spent Fuel & High-Level Waste (HLW)
5) Safety Issues at Power Plants
 Meltdowns & Accidents (Three Mile
Island, Chernobyl & Fukushima Daiichi)
6) Turkey Point Expansion
Turkey Point Expansion


Finally, FP&L has petitioned the Nuclear
Regulatory Commission (NRC) for
permission to construct 2 new reactors at
Turkey Point, and hopes to receive final
licensing in 2017. Construction would
begin in 2020.
The new reactors would use reclaimed
water from a Miami-Dade County sewagetreatment plant, but backup cooling water
would come from wells drilled deep in the
Floridan aquifer.


Turkey Point Expansion
If built, FP&L officials say the plant
would save the state $100 billion in
fossil-fuel costs, cut CO2 emissions by
481 million tons, and provide 800
permanent jobs.
NextEra (FP&L’s parent company) writes
“… if approved and constructed, the new
Turkey Point nuclear reactors would
comply with NRC standards for nuclear
plants and be built more than 25 feet
above current sea level, well above any
predicted rise in sea level.”
Turkey Point