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Early Realization of Fusion Electricity Target and Path. Presented at FESAC Development Path Panel Laurence Livermore National Laboratory, USA on 28 October 2002. by Kunihiko OKANO Central Research Institute of Electric Power Industry (CRIEPI)
Presented at FESAC Development Path Panel Laurence Livermore National Laboratory, USA on 28 October 2002
by Kunihiko OKANO
Central Research Institute of Electric Power Industry (CRIEPI)
Based on the contributions by
K. Tokimatsu (RITE)
S. Konishi (JAERI),
Y. Asaoka, R. Hiwatari and K. Tomabechi (CRIEPI)
By what time the fusion should be ready?(1) From an environmental point of view
Our target to keep the concentration of CO2 less than 550ppm after 2100
What we have to do?
Reduce the gradient of CO2 production by using all the available technologies
2)After the middle of this
Reduce further by Introducing new technologies
There are a lot of competitors. If fusion is not ready in time as one of these new technologies, the motives (and budget) for fusion study might be diminished.
By what time the fusion should be ready?(2) Technological maximum of deployment pace
Pace of fusion energy deployment is restricted by TBR and plant manufacturing capacity
How high pace is possible?
Asaoka et.al, Fusion Technol. 39(2001)518 Tokimatsu et al., Fus. Science & Technol. 41(2002)831
IIC case (Initial Intro. Constraint)
Initially, TBR is a major constraint. To achieve a similar pace to the history of fission plants, TBR=1.08 is required (with 75% plant availability).
After 100 plants constructed , the manufacturing capacity may become the major constraint;
we assume 100GW/y as an upper limit.
Fusion plants (estimated)
History of Fission plants
This curve gives a possiblemaximum pace. The actual pace and the share should be determined by competition with the other energy sources and such an analysis requires a sophisticated model for the global energy assessment.
0 10 20 30 40 50
By what time the fusion should be ready?(3) Break even cost for fusion plants
K. Tokimatsu used a world energy and environment analysis model code LDNE21 to assess a possible contribution of fusion energy in the world energy supply.
In the BAU (Business as Usual) case, break even cost for fusion is less than 50 mil/kWh in 2050, which may be difficult to achieve by fusion plants: No contribution by fusion will be expected.
In the 550ppm case, the break even cost in 2050 is 50-110 mil/kWh, which may be attainable.
ARIES-RS (N=5.0): COE=64-86mil/kWh
COEn=COE/COEcoal =1.5-2.0 (in USA)
R. Miller, Fus. Eng. Des. 49-50(2000)33
CREST (N=5.5): COE=12yen/kWh
COEn=1.2 (in Japan)
K. Okano et al. Nucl. Fus., 40(2000)635.
Our possible target for 1st commercial plant: COEn<1.5
By what time the fusion should be ready?(4) Possible contribution of fusion energy
In the LDNE21 model, the break even COE at the introduction year is assumed and the COE will be reduced by a rate of 2.3%/y for the initial 25 years. The maximum pace is limited by the above IIC case.
The calculation gives the shares of various energies so that the global energy cost is minimized.
Early introduction of fusion is critical in order to provide a significant contribution of the fusion energy.
"Introduction in 2070" seems too late in order to meet people's expectation as a New Technology.
A fusion plant of COEn<1.5 by the middle of this century. How?
For 3GWth output:
A simple scaling proposed by CRIEPI based on COE analysis in Japan, where a plant availability =0.75 has been assumed.
Examples for COEn=1.5: Bmax=20T(on coil), N=3.4 thermal efficiency th=40%
Bmax=16T(on coil), N=3.9 thermal efficiency th=40%
The early DEMO on the fast-track must be designed sufficiently conservatively, but also the operative range must cover the above parameter ranges.
*Subcommittee of the Fusion Council for Fusion Development Strategy held by the Atomic Energy Commission.
Long time burn at Q>10 with technology integration (except for blanket)
Burn control for Q>10, N<3, steady state
based on Ferritic steel and water cooling
but complete replacement by advanced blankets will be possible
Advanced plasma high p for steady state high N for low cost (compact) high Q burning control
ITER + supporting machine like JT60SC
Fully steady state burn with N>3.5 with suitable HH & fGW
Advanced materials long life high temp.
ITER test module
Blanket development TBR >1 high efficiency easy maintenance
SC water Gas Liq.metal
developed in parallel
Burn up ~20% High efficiency
developed in parallel
13T 16T 20T
Advanced Technology for non-replaceable compo. ex. Super conductor
High magnetic field High current density
based on the presentation by Prof. Inoue at Int. Sym. for ITER, Jan 24, 2002
It is mandatory to demonstrate net electric power > 0MW in the initial phase of DEMO operation. The design must be sufficiently conservative, like ITER. Major parameters and basic components must be tested by ITER. We assume a minimum extrapolation from the high Q operation of ITER (not advanced operational mode).
1) Net TBR>1 must be achieved
(with Pw~1MW/m2 at initial phase, ~3MW/m2 at final phase)
2) At least, stable net electric power generation must be demonstrated:
Pnet = (gross power) - (circulating power)
Pnet >0 must be guaranteed with minimum extrapolation from ITER ignition plasma parameters (for example N<2.0, HH<1, fGW<0.9).
This is because that we have to start the DEMO design within 5 to 8 years after ITER first plasma (2014?), in order to complete the construction of DEMO plant and to demonstrate Pnet>0 before 2035-40.
3) The plant must have a capacity to test advanced plasma up to N>3.5 (and Pf up to 3GWth), which may be attained during the ITER operation after the initial phase of BPP. It will allow to achieve 400-600MWe in the net electric power and a next path toward COEn<1.5.
Parameter Scan for DEMO by System CodeFUSAC (fusion power plant system analysis code)
With an extensive analysis by FUSAC, covering the plasma parameter ranges listed in the table, the database for about hundred thousand (100,000) operational points has been constructed .
* Based on the communication with the ITER team, we convinced for the feasibility of the quoted values. # The 200MW limit comes also from a possible number of ports available in the Tokamak machine.
Boundary lines of N, HH and fGW show the design points where the maximum Pf has been obtained with the corresponding N, HH and fGW, respectively.
With N=1.8, HH=1.0, fGW= 0.85 (ITER ref. design）, Pnet=0 is achievable.
With N=3.5, HH=1.2, fGW <1.0 (possible by ITER）Pnet=600MWe is achievable.
Pnet=900MWe with th =40%,
with N=2.5, Pnet=0
with N=4.0, Pnet=600MWe
This is desirable, but may be too optimistic. We may fail for Pnet=0.
with N=1.5, Pnet=0
with N=3.0, Pnet=600MWe
This is too pessimistic and too expensive. No next path toward COEn<1.5 will be expected with N<3.
1. An earlier introduction of fusion results in a larger impact in the world
Introduction in 2070 seems too late, to satisfy people's (tax payer's)
Possible maximum share of fusion energy in 2100 is
~20% for 2050y introduction and nearly zero for 2070y introduction.
2. Break even cost for fusion in 2050 is estimated as 50-110 mil/kWh for
the 550ppm restriction case.
Based on the previous reactor design studies, COE less than
50 mil/kWh seems difficult to achieve, but 70-100 mil/kWh might be
by 2035-40, the design must be sufficiently conservative and
practical, because the failure of initial operation for Pnet>0 is
Such a plan should be a practical one rather than an overly
4. Based on the conservative design policy described above,
a design with R~7.5m can be a candidate for Demo, because
a) With ITER reference parameters (bn=1.8, HH=1.0, fGW=0.85),
Pnet = 0 with Pw~1.0MW/m2
b) With parameters of advanced plasma (possible by ITER)
(bn=3.5, HH=1.2, fGW=1.0),
Pnet=600-900MWwith Pw=3~4MW/m2is attainable.
Then the path toward the break even cost may be in sight.
A design of DEMO with R=7.25m is in progress in the CRIEPI,
although another optimization may be found with different design policies.