Briefing to DOE Office of Science
on Fusion Chamber Technology
Prepared on behalf of the US Fusion Chamber
Technology Community by Mohamed Abdou
For
Dr. Ray Orbach, Dr. Anne Davies, and
Dr. Roberto Peccei
Washington, D.C., June 3, 2003
Chamber Technology (CT) Research must continue to be
a key element of the US Fusion Energy Sciences Program
under all scenarios of budget level and research focus

CT Research plays a central role in understanding and defining the key scientific and
engineering questions, including direction of plasma physics research, that need to be
addressed for fusion to be viewed as viable (“headlights”)

CT research is the key to demonstrating the principles of tritium self-sufficiency,
the fundamental premise of fusion as an exhaustible/renewable energy source

Most of the key issues related to practicality and attractiveness (safety, power
density, environmental impact, economics) of fusion energy are Chamber-related

Proceeding with ITER makes Chamber Research even more critical. The dominant
features of DT burning plasma are:
a)
burning tritium, which must be supplied,
b)
emitting neutrons, which must be safely captured, and
c)
producing high heat fluxes, which must be handled.
All of these features require Chamber Technology (first wall, blanket, shield, etc.) that
will work reliably in the “neutron-tritium-vacuum- magnetic field” environment
Question: What should we do to communicate this message to
those who influence fusion policy outside DOE?
The importance of Chamber Technology has been
clearly recognized by all Fusion Advisory Panels,
Planning Studies (e.g. the latest 35-yr plan by
FESAC), and all the world fusion programs
 This is why the fusion community was shocked (and fusion’s critics delighted)
by the FY04 budget submission (terminating Fusion/Chamber Technology).
 This situation can undermine the credibility of any fusion research or fusion
energy development plans, with devastating consequences to the US Fusion
Program’s ability to make progress.
FESAC Letter to Dr. Orbach: “However, design and construction of ITER
will be extremely demanding with regard to fusion technology. Thus FESAC
is puzzled by the elimination in FY2004 budget of funding for fusion
technology. This loss will seriously compromise US participation in ITER as
well as other burning plasma research activities.”
The community appreciates Dr. Orbach’s efforts to move the fusion program
forward. We also appreciate the efforts by Dr. A. Davies and OFES staff to rectify
the situation. But we need to provide a reassuring message to the U.S. Chamber
Community, especially young scientists, and to our international partners.
The Chamber serves 2 of the 3 fundamental functions of
fusion energy systems:
(1) breed sufficient tritium to assure that the plasma is self-sustained and that fusion
is a “renewable” energy source
(2) high-temperature power extraction in a practical, reliable, safe, and economical
fusion energy system.
CT Research: …
 embodies the scientific and engineering research required to understand, develop, design, test, build, and
operate safely and reliably the systems that “hold” and surround a burning plasma,
 includes all components and functions from the edge of the plasma to the magnets: the first wall, conducting
shells, breeding and non-breeding blankets, cooling systems, radiation shielding, vacuum vessel, electric and
thermal insulators, tritium permeation barriers, and structure,
 provides state-of-the-art predictive capabilities for many technical disciplines required for the fusion program:
neutron/photon transport, neutron-material interactions, heat/mass transfer, thermofluid MHD, thermal
hydraulics, structural mechanics, thermomechanics, thermo-dynamics, chemistry, radioactivity, decay heat,
engineering scaling, reliability methodology, etc,
 develops key non-structural materials (e.g. solid breeders, neutron multipliers, insulators, etc.) and material
systems interactions, and
 is made up of scientists and engineers who must understand and help resolve the competing requirements of
high performance plasma operation with the material, engineering and safety limits of the chamber, as well as
the production of sufficient tritium and efficient reliable energy.
The kind of training needed to perform research and engineering
within this highly constrained fusion system takes many years of
education and experience. (Building competence takes decades)
Importance of the Chamber Technology Research
for ITER and DEMO (selected examples)
 All of the chamber component design ideas for ITER came from CT Research activities that started in
the 80’s (BCSS, FINESSE, INTOR, IEA, etc.). The ITER Chamber design took the longest of all the
major systems because of the need to resolve many scientific and technological challenges.
 An understanding of the CT for the step beyond ITER will be crucial in setting relevant physics
programs in ITER, in the same way that the CT constraints for ITER were critical in shaping the
physics programs of present plasma experiments
 CT Research provides training and development of skills for people that go on to lead other
programs. (The head of the US Safety Program, the Head of the Vacuum Vessel Division in KSTAR,
and the Head of the PFC components in Europe and ITER, for example, were all students trained in
the US Chamber Technology Research Program. Many of the fusion leaders and university
professors in Europe and Japan were trained as part of the US CT Research Program).
 CT research results were a major driver for starting physics research on steady state and disruptionfree plasmas
 CT methods for predicting radiation fields allowed optimized shield design and a huge size reduction
of ITER and power plants; methods for testing materials in fission reactors
 CT Research also develops innovative concepts for better plasma performance and more attractive
fusion systems. As one example, the concept of liquid walls, originally advanced as a power handling
innovation, has also been embraced by plasma physicists as an effective tool to control edge
recycling and MHD stability
ITER is not only a burning plasma experiment, but also an experiment
to test technologies in the fusion environment. CT has a leading role
in both the basic device and the blanket testing mission
Tritium supply and self-sufficiency
are “Go-No Go” issues for fusion energy,
as critical NOW as demonstrating a burning plasma
 There is no practical external source of tritium for
fusion energy development beyond a few months
of DT plasma operation in an ITER-like device.
It takes tens of “neutron-poor” fission reactors to
supply one fusion reactor.
 There is NOT a single experiment yet in the fusion
environment to show that the DT fusion fuel cycle
is viable. Test blanket program in ITER is vital.
 ITER has now set the schedule
for test blanket
.
modules beginning “day 1” of operation.
R&D must start immediately
Powerful DT Burning Plasma Experiments
such as ITER Must Breed their own Tritium
Tritium Consumption in Fusion Is
HUGE!
World Tritium Supply Exhausted by 2025
by ITER at 1000MW at 10% Availability
or ITER at 500 MW at 20% Availability
Production & Cost from fission
are LIMITED & EXPENSIVE!
 CANDU Reactors: 27 kg over 40
years, $30M/kg (current)
 Fission reactors: few kg per year,
$200M/kg!! (projected cost)
Conclusion
Chamber technology is not
just for power reactors.
It is essential for continuing
burning plasma and fusion
research
Projected Ontario (OPG) Tritium Inventory (kg)
 55.8 kg per 1GW.year fusion power
30
CANDU
Supply
w/o Fusion
25
20
15
10
1000 MW Fusion
10% Avail,
TBR 0.0
5
0
1995
2000
2005
2010
2015
2020
Year
ITER-FEAT
(2004 start)
2025
2030
2035
2040
2045
Recent History of US Chamber Technology
 The US Chamber Program enthusiastically worked on CDA
and EDA phases of ITER, playing critical roles
 The Chamber Program suffered a MAJOR Budget cut in
1996. OFES and the community worked very hard to
maintain a “bare minimum of critical skills “ (skills that took
30 years to develop)
 Over the past few years, CT research focused on developing
innovative ideas for the Chamber that could substantially
improve the plasma performance and our vision of fusion
Now, a New Emphasis is required:
As we move forward with joining ITER, the CT
community is ready to restructure its activities
to best support the new initiatives
New Emphasis for Chamber Research with
rejoining ITER
1.
Test Blanket Module Program – Restart tritium breeding blanket test module R&D program
for ITER reflective of the US priorities on chamber systems. This is critical as the ITER plan calls
for testing from day-1 of operation in 2013, and a decision on blanket test modules by 2005 in
order to initiate design, fabrication and out-of-pile testing. [US has been the World Leader]
2.
FNT Support for ITER Basic Device – As ITER moves toward construction it will need
more accurate predictions in the nuclear area (radiation fields, shielding, tritium, etc.) and chamber
technology help to resolve remaining issues in ITER design
3.
Advanced Chamber Configurations – Continued R&D, with emphasis on innovation and
underlying science, towards high pay-off chamber options that can most dramatically affect the
viability and attractiveness of fusion energy. (e.g. thin liquid walls, advanced materials)
4.
Fundamental Predictive Capabilities – Continue to develop, advance and support
computational models, codes, and tools (e.g. thermofluid MHD, neutronics, radioactivity, etc.)
needed by other key fusion programs: Safety, Materials, PFC, Advanced Design Studies
5.
FNT Experimental Techniques and Diagnostics – Develop experimental techniques and
diagnostics for operation in magneto-nuclear test environments (ITER, CTF, etc.). Evolve technical
and programmatic strategies for FNT testing and development.