Satoshi Konishi

1
7th International Symposium on Fusion Nuclear
Technology
A critical review and comparison of power reactor
blankets from nuclear technology and
socio-economic aspects
Satoshi Konishi Institute for Advanced Energy,
Kyoto University May.25, 2005
Contents - Broader Externality aspect -
Tritium release to the environment - Waste
strategy - Fuel supply - Deployment to
hydrogen market
Special Thanks to Kunihiko Okano, Yusuke Ichimasa
and Kenji Tobita
2
Socio-Economic Aspect of Fusion
Institute of Advanced Energy, Kyoto University
Future energy will be evaluated by social
preference. Such evaluation will consider all
the possible impacts and effects to future
society and environment.
Government
Public
Damage/cost/ Externality
Industry
funding
Future Social Demand
Energy Supply
Fusion
Other Energy
Different outcome are expected for sponsors.
3
How fusion affects?
Environment,Society
Facility
Blanket
Wastes (Solid nuclides, T,C-14)
Plasma
Heat Transfer
Exhausts (T,heat)
Fuel, Material (D,Li-6,..)
(Recycle)
Energy (Electricity)
Economy
Fusion will be evaluated - what it
consumes - what it exhausts - what
it generates , and - what it leaves
Blanket is the key For Socio-economic Feature of
fusion
4
How fusion will benefit public?
- Energy sales is not the only outcome of the
research. ?Externality economical
effect out of the market
Impact by various pathways -outside of
energy market - estimated with economical value
(monetary term) environmental negativepollution,
global warming environmental positiverecycling,
cleaning, reduced emission social
negativenuclear proliferation, terrorism, fear
of risk social positive security, backstop,
technology
positive
negative
risk
All the risks and benefits evaluated from the
viewpoint of sponsor market sales is only a
part cost is not a good measure but cost
affects the market share
benefit
cost
social
security
Environ.
recycle
pollution
cleaning
warming
5
Investment for nuclear technology
various sponsors provide funding different
purpose, different phase of development investmen
t for research is a certain fraction of total
sales ?investment must yield benefit to
sponsors
sales
Fission reactor case
1960
industry
Basic research
transfer
utility
Research institute
Further competitiveness
Research institutes
improvements
commercialization
6
Variety of fission reactors developed
7
Strategies for blankets
Generations of blankets fit different phases -
Fusion has multiple generations with single plasma
Learn from the history of fission.
1) Technically possible. (liquid
metal) 2) Governments policy and social
preferences. (graphite, heavy water) 3)
Market selection. (light water reactor)
Each generations has different purpose.
-expected functions of blanket differs.
8
Fusion development strategy
Drawn from Fast track working group in Japan,
2002,Dec.
2000
2010
2020
2030
Power Demo
Generation
ITER
BPP
Const.
EPP
TBM
module1
module2
Tokamak
Test
High beta, long pulse
Evolution required In a same facility
IFMIF
KEP
EVEDA
Const.
New line
10dpa/y
20dpa/y
RAF
In pile irradiation
Full irrad.
1/2 irrad.
The 1st Blanket will aim at earliest power
generation. Next target will be deployment into
the future society.
9
Energy Conversion Issue
Blanket heat transfer media will have to fit
advanced energy.
Steam 500 ? or high temperature He 900?
10
Introduction into the market
Possible introduction price of Fusion
increases with time as
fossil price increases.
150
mill/kWh
145
125
125
109
100
92
Current target of the development
75
65
Possible Introduction price
50
25
0
2050
2060
2070
2080
2090
2100
year
Target cost of electricity varies as a function
of Introduction time.
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Tritium processing systems
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Emission dominated by normal detritiation
Water based heat transfer requires isotope
separation.
12
Impact pathway of tritium
Tritium is detectable far below the level that
affects health.
13
Impact of radioactive emission
Tritium released from the facility diffuses but
not disappear.
According to the LNT hypothesis by
ICRP, detriment increases with distance.
Normal release accumulates in the environment.
Dose is negligible compared with natural
radiation, but detectable in environment, foods
and drinking water. Same thing happens with C-14
and worse.
14
Waste Disposal Issue
15
Tritium confinement in acceident
TRITIUM containing medium will be confined
expansion volume He expansion pool water
(easy) other liquids IN CASE OF SPILL,
TRITIUM IS RECOVERED BEFORE GOING OUT TO THE NEXT
BARRIER
BUILDING
DETRITIATION SYSTEM
DETRITIATION SYSTEM
volume
Accidental spill can be recovered with normal
detritiation. Heat transfer media and pressure
requires different confinement.
16
Fuel Supply Issue
Availability and stability of fuel resource will
be important.
TBR and plant inventory
Deuteriumits own detritiation Initial tritium
other power plant or its
own Lithium cooling sea water Lithium6
lithium metal production Carbon liquified
natural gas - reduction of
carbon-14, i.e. removal of
nitrogen and carbon-13
Synergetic isotope separation systems must be
considered for fuel and material supply.
17
Possible share of fusion energy
Maximum Construction Speed Case
Initial Tritium Constraint Limit
Share of fusion in 2100 ()
Fusion introduction year
Early introduction is essential for fusion.
(Market will be occupied) Construction speed may
limit possible fusion share. Avoiding initial
tritium constraints increases capability of
fusion.
18
Conclusion
?Deployment of fusion requires socio-economic
consideration. economy passive safety in
accidental scenarios normal tritium emission
solid waste issues fuel and material
supply and control ? Socio-economic
features are strongly dependent on blanket
economy high temperature, high efficiency,
hydrogen environment - low activation, short
life of rad-waste ?Strategic consideration
generations of blanket concepts have different
purposes. Evolution of blanket in ITER and DEMO
is essential.