The Significance of Helium-3 Fusion
Using Lunar Helium-3 to Generate Nuclear Power
Without the Production of Nuclear Waste
Professor G. L. Kulcinski
Lecture 26
March 26, 2004
The Use of Fusion Fuels Will Evolve in the Future
1st Generation
2nd Generation
3rd Generation
D + T → n (14.07 MeV) + 4He (3.52 MeV)
D + D → n (2.45 MeV) + 3He (0.82 MeV) {50%}
→ p (3.02 MeV) + T (1.01 MeV)
{50%}
D + 3He → p (14.68 MeV) + 4He (3.67 MeV)
3He
+ 3He → 2p + 4He
(12.9 MeV)
Why Are We Interested in
the Advanced Fusion Fuel
Cycles if DT Fusion is
Easier?
The Public Developed a Resistance to
Nuclear Power in the Late 20th Century
•
The resistance seems to be largely based on:
1) Fear of radioactivity releases
2) Uneasiness with long-term nuclear waste storage
3) Fear of proliferation of nuclear weapons grade material
• All of the above problems stem from the nuclear reaction:
1) Radioactive fuel
2) Radioactive reaction products
3) Neutrons
The 20th Century Approach to Fusion Only Partly
Alleviates Public Concerns About Nuclear Power
Public Concern
Radioactive Releases
How DT Fusion Addresses Concern
Avoid runaway reactions and "meltdown" scenarios
However, still have gigacuries in reactor in the event
of an accident
Long Term
Radioactive Waste
Storage
Choice of fuel and structural material can reduce
effective half life to < 100's years
However, radiation damage and replacement of
components can produce large volumes of radioactive
waste
Proliferation
Reactor does not require fissile or fertile material
However, excess neutrons can be used to breed
fissile fuel
Can the Use of Fusion Fuels
Alleviate the Public’s Fear About
Radioactivity?
Some Fusion Fuels Have More Radioactivity
Associated With Them Than Others
Fuel
Cycle
Radioactive
Fuel
Direct Radioactivity
Indirect Radioactivity
DD
--
n
T
--
n
DT
T
n
--
--
n
T
D3He
--
--
--
--
n
T
3He3He
--
--
--
--
--
p6Li
--
--
--
--
n
T
7Be
11C
p11B
--
--
--
--
n
Small
14C
small
Half Life: T = 12.3 y, 7Be = 52 d, 11C = 0.33 h, 14C = 5,600 y
The Form of Energy Released in a Magnetic
Fusion Device Depends on the Fuel Cycle
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Bremsstrahlung
Synchrotron
Transport
Neutrons
DT
DD
D3He
3He3He
The Number of Neutrons Generated by Helium-3
Fusion Fuels is Very Small
12
11
Rel. n/MeV 10
Released in
Fuel
8
7.5*
6
5
4
2
0
1
Fission
0.04–0.2
DT
*burn
*burn half
half of
of TT bred
bred
DD
D3He
Fusion
0
3He-3He
Nuclear Energy Conversion Efficiencies
60-70
D-3He/3He-3He
DD
50
45
DT
40
LMFBR
LWR
33
0
10
20
30
40
50
60
Electrical Conversion Efficiencies
70
80
The Use of 2nd and 3rd Generation Fusion Fuels Can Greatly
Reduce or Even Eliminate Radioactive Waste Storage Problems
Class of
Waste
Relative
Cost of
Disposal
LWR Fission
(Once Through)
DT
(SiC)
D3He 3He3He
(SiC) (any material)
Relative Volume of Operation Waste/GWe-y
Class A
1
several times
times
several
several times
times several
Class
Class C
C
Class
Class C
C amount
amount
amount
amount
Class C
≈10
Deep
Geological
≈1000
(Yucca Mtn.)
55
Characteristics of D
3
He Fusion Power Plants
• No Greenhouse or Acid Gas Emissions During
Operation
• Very High Efficiencies (>70%)
• Greatly Reduced Radiological Hazard Potential
Compared to Fission Reactors (<1/10,000)
• Low Level Waste Disposal After 30 y
• No Possible Offsite Nuclear Fatalities in the
Event of Worst Possible Accident
Characteristics of 3 He 3 He Fusion Power Plants
• No Greenhouse or Acid Gas Emissions
During Operation
• Very High Efficiencies Possible (>70%)
• No Residual Radioactivity After 30 Years
of Operation (No Radioactive Waste
or Nuclear Safety Hazard).
Nuclear Energy Without
Nuclear Waste !!
How Can We make the
Advanced Fusion Fuel Cycles
“Burn” More Efficiently?
Fusion Cross Sections for the First Three Generations
Source: J. F. Santarius
In a Maxwellian plasma, most of the fusions come
from the high energy “tail” of the ion distribution
Source J. F. Santarius
In order to generate enough ions in the tail of a
maxwellian distribution a D3He plasma would
have to be heated to >100 keV
Source-J. F. Santarius
To Avoid the Limitations of Maxwellian Plasmas,
Farnsworth Invented the Inertial Electrostatic Concept
1. Positive ions are created from
the fuel gas near the outer grid,
and are accelerated towards the
negativity charged inner grid.
2. The ions can oscillate through
the inner grid several times,
creating a concentration of high
temperature ions.
3. The ions can collide, creating a
fusion reaction.
4. The ions can also undergo a
charge exchange, creating a fast
neutral.
5
1
2
3
4
5. Fast neutrals can collide
with the neutral gas, also
creating fusion reactions.
6. High energy fusion products,
such as protons and neutrons, are
created and can be used in many
different applications.
Using the IEC concept, accelerating ions to 100 keV makes
much more efficient use of the input energy
Source- J. F. Santarius
IEC Operation
High-Voltage
Feedthrough
RGA
Proton Detector
Neutron Detector
D2
D
D222 D+
+
D
D22
DD
D
D+
2
+ D2
D
2
+
+
D2 D
D D D
D222
D222
D
D222
D
+
D22
D
D2 D2
+
DD
2
D2
D2
D2
D2 cm
65
D2
D
D2DD
D222
D+ D
D
22
2
+
22
D
D+ D2 D+ D
2
D2
D+
D+
D
+ D2
D222
D222
D+ D
D2
DD
D
D2
D
D222
2
91 cm
Gas Flow
Controllers
50 cm Outer Grid
10 cm Inner Grid
2
Filaments
Pumping System
Steady State D 3 He Reaction Rate Achieved in
Wisconsin IEC Device
reaction
reaction
products
products
electric
electric
potential
potential
well
well
ion
ion
density
density
Voltage
Voltage
~50
~50 keV
keV
(typical)
(typical)
cathode
cathode voltage=55
voltage=55 kV
kV
cathode
cathode current=60
current=60 mA
mA
pressure=1
pressure=1 mtorr
mtorr
The Steady State D-3He Fusion Rate in the UW IEC
Device is Now ≈5 x 107 p/s
(115 kV, 60 mA)
Run 265
90kV, 30mA
UW Performance History
Steady State Proton and Neutron Production
1.0E+09
1.1 x 108 n/s
D-D Neutrons
1.0E+08
5 x 107 p/s
1.0E+07
D-3He Protons
1.0E+06
1.0E+05
1.0E+04
1.0E+03
1.0E+02
Jan-98
Jan-99
Jan-00
Jan-01
Date
Jan-02
Jan-03
Jan-04
Major Societal and Technical Concerns of
Nuclear Energy Options
Fission
1st
DT
Fusion Generation
2nd
DD
D3He
3rd
He/3He
3
Proliferation
none
Nuclear Waste
none
Radiological Hazard
none
Physics Req't.
Hardest
Major Problem
Easiest
Minor Problem
Why Consider the Advanced Fuels for Power Production?
Major Advantages
• Significant Reduction in
Radiation Damage
Major Disadvantages
• Higher operating
temperature
– (permanent 1st wall)
– (higher nτ values)
• Greatly reduced (or no)
radioactivity
• Potential for Direct
Conversion
• Lower plasma power
density or yield
– (higher efficiency & lower
waste heat)
– (requires higher beta or
ρr)
• Fuel source-3He
– (requires NASA
collaboration)
Significance of Lunar Helium-3
11 tonne
tonne of
of He-3
He-3 can
can produce
produce
10,000
10,000 MWe-y
MWe-y of
of electrical
electrical energy.
energy.
40
40 tonnes
tonnes of
of He-3
He-3 will
will provide
provide
for
for the
the entire
entire U.S.
U.S. electricity
electricity
consumption
consumption in
in 2004.
2000.
At 1 Billion Dollars a Tonne the
Energy Cost of Helium-3 is Equivalent
to Oil at $7 per Barrel
There is 10 Times More Energy in the
Helium-3 on the Moon Than in All
the Economically Recoverable Coal, Oil
and Natural Gas on the Earth
Conclusions
The use of second and third generation fusion fuels could
revolutionize the Public's view of fusion power by:
1) eliminating one of the greatest barriers to public acceptance
of nuclear power – the concern over radioactive waste,
radioactivity releases, and proliferation of weapons grade
2) allowing off-the-shelf structural materials to be used, thus
eliminating expensive neutron test facilities & long
development times.
3) allowing high efficiency operation and in-city siting of
electrical power plants
They Said It Couldn’t Be Done
"There
"There is
is not
not the
the slightest
slightest indication
indication
that
that [nuclear
[nuclear energy]
energy] will
will ever
ever be
be
obtainable.
obtainable. ItIt would
would mean
mean that
that the
the
atom
atom would
would have
have to
to be
be shattered
shattered at
at
will."
will." –Albert
–Albert Einstein,
Einstein, 1932
1932
"Man will not fly for fifty years."
–Wilbur Wright, 1901
"Heavier-than-air flying machines are
impossible." –Lord Kelvin, president,
Royal Society, 1895
"Anyone
"Anyone who
who looks
looks for
for aa source
source of
of
power
power in
in the
the transformation
transformation of
of the
the
[nucleus
[nucleus of
of the]
the] atom
atom is
is talking
talking
moonshine."
moonshine." –Ernest
–Ernest Rutherford,
Rutherford, 1933
1933
"Space
"Space travel
travel is
is utter
utter bilge."
bilge." –Dr.
–Dr. Richard
Richard
Wooley,
Wooley, Astronomer
Astronomer Royal,
Royal, space
space advisor
advisor
to
to the
the British
British government,
government, 1956
1956
"Airplanes
"Airplanes are
are interesting
interesting toys
toys but
but of
of no
no
military
military value."
value." –Marshall
–Marshall Foch,
Foch, future
future WWI
WWI
French
French commander-in-chief,
commander-in-chief, 1911
1911