Dennis Whyte Fusion Presentation to ASP June 16 2015

1Whyte, ASP Fusion Lunch, 06/15

MIT Plasma Science & Fusion Center

Smaller & Sooner:��Key New Technologies to Accelerate the��

Development of Fusion Energy

Dennis Whyte MIT Plasma Science and Fusion CenterMIT Nuclear Science and Engineering

With grateful acknowledgement to colleagues & studentsat MIT and Princeton Plasma Physics Lab

American Security Project “Energy Week” LuncheonNew York, June 2015


The fusion of light nuclei is the energy source of stars, and basically, the universe

Big ball of hydrogen “plasma”

Interior temperature ~ 15 Million C


The fusion of light nuclei is the energy source of stars, and basically, the universe

On EarthHeavy types of hydrogen100 million degrees C10 atmospheres of pressure


Fusion is the ultimate energy source

•  Limitless fuel��

•  No radioactive waste in fuel cycle•  No proliferation

•  Inherently safe

•  No greenhouse gases

•  Million times power density of “chemical” energyØ Minimized environmental footprint

•  Can rapidly scale to large % of energy demand


Slide Title

•  Points


Fusion is the ultimate energy source

•  Limitless fuel��

•  No radioactive waste in fuel cycle•  No proliferation

•  Inherently safe

•  No greenhouse gases

•  Million times power density of “chemical” energyØ Minimized environmental footprint

•  Can rapidly scale to large % of energy demand


Magnetic bottles in toroidal (“donut”) shape have been extremely successful at reaching fusion conditions

On EarthHeavy types of hydrogen ✓ A100 million degrees C ✓ A 2 atmospheres ✓ B


The magnetic bottle is produced with a set of external coils with very large electrical currents passing through them

CurrentIn coil


Fusion is real, made everyday in experiments of different size and configurations around US and world

Alcator C-Mod (MIT)3 atmospheres100 million C JET (UK)

15 million watts fusion power

0.7 m3 m


Outside the US the world is escalating its investment magnetic fusion science by using “superconductor”

technology to produce the magnetic bottle

South Korea

China

Japan

Germany


Yet fusion energy’s development timeline�� has stalled…

Ener

gy G

ain

Year


The ITER fusion experiment: ��The science of fusion is ready, but it takes ��

very large size with ~90’s superconductor technology


Smaller, modular fusion devices are the key to��accelerating fusion’s development towards ��

net energy on decade timescale

! Shippingport:+1954+“Pilot”+Fission+Plant++ ITER+

Pthermal)(MW)) 230+ 500++Core)volume)(m3)) 60++ 1000+Cost)(2012)US)B$)) 0.6+ ~+20+

Cost)/)volume)(M$/m3)) 10+ ~+20+Construction)time)(y)) 3.5+ >+20+

!


Smaller, modular fusion devices are the key to��accelerating fusion’s development towards ��

net energy on decade timescale

! Shippingport:+1954+“Pilot”+Fission+Plant++ ITER+

Pthermal)(MW)) 230+ 500++Core)volume)(m3)) 60++ 1000+Cost)(2012)US)B$)) 0.6+ ~+20+

Cost)/)volume)(M$/m3)) 10+ ~+20+Construction)time)(y)) 3.5+ >+20+

!

JET tokamak: 100 m3 ✓ ~4 years construction ca. 1980 ✓But only 10 MW fusion power


Breakthrough superconductor technology provides a stronger magnetic bottle that does not use electricity à

smaller, sooner fusion energy

“ARC” Volume ~ 100 m3 JET (UK): Volume ~ 100 m3

Bmax = 23 T Bmax = 9 T

Pfusion =10 MWPfusion ~ 500 MW


The way to decrease the size of fusion devices, ��and accelerate fusion energy development, ��is to achieve higher magnetic field strength

βN2

q*2 RB4

Fusion power density

Physics parametersR = linear size, volume & cost ∝ R3��

B = magnetic field strength


The way to decrease the size of fusion devices, ��and accelerate fusion energy development, ��is to achieve higher magnetic field strength

βN2

q*2 RB4

Fusion power density

Physics parametersR = linear size, volume & cost ∝ R3��

B = magnetic field strength

Increase B two-fold à Gain 24 = 16 advantage!

Well known 20+ years ago but could only be done in resistive, energy consuming copper coils à no net energy


Last few years: A new generation of high-temperature, high-field superconductors is

revolutionary for fusion energy

•  Zero resistance

•  Form of strong, flexible tapes à can form joints


REBCO: coated superconductors in ��robust tape form, commercially available

•  Strong in tension due to steel •  Flexible•  Outer Cu coating à simple

solder low-resistance joint•  Stark contrast with old NbSn

superconductor strand & CIC!

REBCO tape composition(not to scale)


Breakthrough superconductor technology provides a stronger magnetic bottle that does not use electricity à

smaller, sooner fusion energy

REBCO superconductors ~4 years construction

Bmax = 23 T Bmax = 9 T

Pfusion =10 MWx B4Pfusion ~ 500 MW


April 2015: New world record of 26.5 Tesla��with REBCO-only, “no-insulation” coil

S. Hahn, J.M. Kim, et al.NNFML, FSU, SUNAM, MITApplied Phys Lett 2015


REBCO superconductor technology is primed to make smaller, sooner fusion possible!

Bcoil(T) 26.5 23

Je (A/mm2) 400 400-500

T (K) 4.2 25

Materials REBCO, SS316L

σmax (MPa) 593 660

Diameter (m) 0.03 ~ 6


Tape superconductors à Demountable coils à Open the magnetic bottle!

F. Mangiorotti, J. MinerviniMIT Ph.D. thesis


Demountable superconductor coils have a profound effect on modularity of fusion design

•  Core is designed as a single integrated unitØ  Synergy with keeping

design of small total mass and volume

•  Fabrication + qualification done completely off-site

Replaceable“core”��module


Demountable superconductor coils have a profound effect on modularity of fusion design

😀😕


Modular core has a profound effect on fusion design: The liquid immersion “blanket”

•  Simple -- No gaps ��

•  Energy & fuel extraction with liquid low-velocity flow

•  No damage limits in blanket

•  Minimize solid replacement ~ 1 m3

FLiBe blanket

Fusionsource


Immersion blanket + 3D printing:��Another revolution for fusion manufacturing and

removing intense heatExternalmotor

Inte

rnal

pum

ps

FLiBe

3D printed car

W

Flibe

2 mm thick

+Internal

Fin


High magnetic field à Reliable, stable physics regimes that have already been demonstrated

Operational limit diagram

βN2

q*2 RB4


The revolution of new superconductor technologies ��is ready to be started

Large sizeSector replacement> 20 year timeline

Modest size ��Modular replacement

< 10 year timeline

Fusion power: 500 MWElectrical power: 200 MW

Fusion power: 500 MW

SameScience!


Near-term, small-scale research can pursue this exciting path for fusion energy


Fusion Energy: Can be soon enough to make a difference!

•  Fusion energy to solve the world’s needs has always been “50 years in the future”.

•  But times have changed! Breakthrough technologies + established fusion science = New design paradigm

•  Demonstration plants can be ready in decade, at reasonable cost & size.

•  Let’s do it.


Thank you!


Additional Materials


Roadmaps to fusion energy should take on risk with variety of weightings in science vs. technology

Lockheed Martin

General Fusion

TriAlpha

Large science risk“Simpler” technology��

Flexible geometryReduced scale

Minimal science riskBreakthrough technologies

Geometry same but modularReduced scale

Science successToo big

Too slow


Slide Title

•  Points


Detachable magnetic coils à ��Idealized liquid immersion blanket à ��

Improved power density with high-T molten salt

Liquid: 450 – 1450 C

Non-toxic, inert

High resistivityGlobal heat removal

Internal ��heat removal


Immersion blanket: high-T molten salt FLiBe��Single-phase, low-pressure flow with ��

minimum MHD effectsExternalmotor

Inte

rnal

pum

ps

•  Fuel Breeding Ratio ~ 1.14•  High thermal efficiency ~ 0.4 - 0.5•  Shielding: ~10 FPY coil lifetime

FLiBe


A fusion energy device heats itself and recycles neutrons internally for tritium hydrogen fuel

Energy Before (MeV)

~ 0.01

~0.01

Energy After (MeV)

14.1

3.5

Plasma physics: T=10 keV



Energy Before

~0.01

~0.01

Energy After

14.1

3.5+

+

Alphas heat plasma through scattering

Plasma physics, MAlfven >1



14.1 MeV

++

Escapes plasma

Nuclear Physics



14.1 à 0

++

Heat

ElectricityNuclear Engineering



++

6-Li + n à He + T

Nuclear Engineering, Radiochemistry



++

Surrounding materials

Nuclear Material Science

sheath

Low-T Plasma Material Science


The recipe for fusion energy success is well known: Gain & Power density & Steady-state

Q = Fusion PowerInput Power

Fusion Power

Heat out

InputPower

Blanket area S

Fusion PowerUnit Size

Gain

Power��Density

Steady-��State


REBCO superconductors performance is constantly improving for application in high-B coils:��E.g. Challenge of field anisotropy in jcrit

B

tape

B

tape


REBCO superconductors performance is constantly improving for application in high-B coils:��

E.g. Field anisotropy in jcrit nearly eliminated last year“Progress in coated conductor development for high magnetic field applications.” V. Selvamanickam, et al.U. Houston Superconductor Workshop, Napa, CA Feb. 2015

Dennis Whyte Fusion Presentation to ASP June 16 2015

Technology

asp fusion lunch