AAWSAP DIRD, Inertial Electrostatic Confinement Fusion, March 2010

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UNCLASSIFIED/ }FOA &FFI@IAL ~!II! er•t I
The proposal is to develop a revolutionary small IEC fusion power unit that could be
commercialized in time to impact the energy crisis we now face. This device would have
the aggressive goal of burning relatively inexpensive aneutronic p- 11B fuel, avoiding
issues of tritium breeding and radioactivity that the D-T burning ITER type devices face.
This breakthrough technology is the resu lt of new understanding of ways to create a
deep potential electrostatic 'well' for improved confinement in an ion injected IEC. This
will be done with specially designed ion guns to inject ions into the IEC with strong
focus and controlled angular momentum. This concept builds on a combination of prior
sma ll scale experiments with gun injected IECs and simulation of their scale-up to
power production using particle-in-cell (PIC) codes and particle tracking analysis
described in earlier sections. The small size of the IEC is a key characteristic. If rapid
development is to be achieved, the ability to employ small size experiments is essential.
Fortunately, confinement scaling in the IEC is in velocity space (vs. physical space
which brings in reducing the surface-to-volume ratio), allowing breakeven and power
production in small-volume plasmas.
Thus in principle, energy breakeven could be demonstrated in the IEC in a very dense
plasma "core" occupying only a few cc volume with only a few l00's of watts in and
out. This extreme is not currently possible, but use of the new gun injected technology
to obtain breakeven in a dense plasma core in the IEC of l00's of cc volume and with
20-25 kW input power seems practical. This proof-of-principle device would
demonstrate the physics of energy production and prnvide the basis for going rapidly
going to practical IEC power plants. This route could lead to power reactors for
distributed power applications in the range of a MW that are only a fraction of the size
of an ITER Tokamak type plant or even current fission nuclear plants. Small units of this
type could be rapid ly deployed to allow fusion power to have a real impact on t he
growing need for energy. Fusion power would then become a vital element in our goal
of energy independence.
VISION OF A FUTURE P- 118 FUSION PLANT
In the ultimate power plant, the preferred fusion reaction would employ aneutronic p­
11B fuel, which fuses to produce energetic alpha particles with no neutrons and minimal
radioactivity. This eliminates radioactive tritium breeding and corresponding tritium
inventory, activation and damage to reactor structural materials and the massive
shielding and radiation protection in traditional fission and D-T fusion reactor systems.
In this case, p- 11B reactors in the central IEC core result in MeV energy alpha particles
according to the reaction: p+ 11B 3a. Due to its inherent non-Maxwellian (beam-like)
plasma, the IEC is especially well suited for burning a fuel such as p- 11B which requires
high energies (~150 keV) . [See Figure 6.1]. In operation, a bulk of the IEC driving
energy is given to ions so an applied voltage of~ 180 kV provides ion energ ies nea r the
peak of the p- 11B cross section. In contrast, in Maxwellian-type plasmas typical of
magnetic confinement devices, energy is expended t o create ions over a wide
distribution of energies. Thus, Tokomaks are designed to operate at much lower ion
energies (~20-30 keV) suitable for D-T fusion. The key physics challenge then for the
IEC is to achieve good ion confinement via strong ion trapping (i.e. large number of
recirculations) in the potential well. This trapped plasma must meet the Lawson
criterion for energy to break-even with p-11B, n, ~ 1016 cm·3- sec (two orders of
magnitude above the requirement for D-T fusion). Here n is the ion density and -r is the
ion confinement time. Assuming the converged core density in the potential well of
UNCLASSIFIED/ }FOA: OFFICI0L: !!ii ODIL:¥
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