The SuperCable:Dual Delivery of Chemical and Electric Power

Paul M. GrantEPRI Science Fellow (retired)

IBM Research Staff Member EmeritusPrincipal, W2AGZ Technologies

w2agz@pacbell.netwww.w2agz.com

2004 SuperGrid 225 - 27 October 2004, Urbana, Il

Technical Plenary Session – Levis Faculty Center -- UIUCMonday, 25 October 2004, 9:30 AM

The Discoveries

Leiden, 1914

Onset TC = 40 K !

La- Ba- Cu- O

Onset TC = 40 K !

La- Ba- Cu- O

Zürich, 1986

+ +

+ +•e-

+ +

+ +•e-

Superconductivity 101C ooper P r ob lem

2

s ingle particles

pairs

e ik r1

e -ik r2

H(k) + H(-k) + V(k)

V(k) = -V0 0 k f dk e ik(r

1 - r

2)

(r1-r2) = (r1-r2)(s 1,s 2)

2 e-2/N(E f)V 0

F er m ion -B oson F eynm an D iagr am

q

k1

k'1

k2

k'2

)/1exp( 14.1 DCT

(Niobium) K 5.9

,28.0

,K 275

C

D

T

)/1exp( 14.1 DCT

(Niobium) K 5.9

,28.0

,K 275

C

D

T

•-• eeee

GLAG

G d rm

i e A i e A a b[ ] [*

( * ) *( * ) * * *] 3 12

1

2

( ) ( )

( ) ( )

(| | )

( / )

/

* *

i f f f

i f f f f f

a b f

A

L

A

A A

A

2 2

2 12

2

12

0

1 0

0

2

The Flavors of Superconductivity

1/4

HC1H

-M

Meissner

HC1

Normal

TCTemperature

Mag

net

ic F

ield

<

Type I

Abrikosov Vortex Lattice

DipoleForceDipoleForce

H

The Flavors of Superconductivity

1/4

HC1H

-M

Meissner

HC1

Normal

TCTemperature

Mag

net

ic F

ield

HC2

HC2

Mixed

>

Type II

Abrikosov Vortex Lattice

DipoleForceDipoleForce

J

H

FF

The Flavors of Superconductivity

1/4

HC1H

-M

Meissner

HC1

Normal

TCTemperature

Mag

net

ic F

ield

HC2

HC2

Mixed

>

Type II

NOTPERFECT

CONDUCTOR!

Abrikosov Vortex Lattice

DipoleForceDipoleForce

J

H

FF

“Pinned”

IrreversibilityLineIrreversibilityLine

Meissner

HC1

Normal

TCTemperature

Mag

net

ic F

ield

HC2

Mixed

The Flavors of Superconductivity

R = 0

R 0

Meissner

HC1

Normal

TCTemperature

Mag

net

ic F

ield

HC2

Mixed

No More Ohm’s Law

Typical E vs J Power Law

0.0E+00

5.0E-06

1.0E-05

1.5E-05

2.0E-05

0 25000 50000 75000

J (A/cm^2)

E (

V/c

m)

E = aJn

n = 15

T = 77 KHTS Gen 1

E = 1 V/cm

ac Hysteresis

1/4

HC1

H

-M

HC2

H

M

H

M

TC vs Year: 1991 - 2001

1900 1920 1940 1960 1980 2000 0

50

100

150

200T

emp

erat

ure

, T

C (K

)

Year

Low-TC

Hig

h-T

C

164 K

MgB2

Oxide Powder Mechanically Alloyed Precursor

1. PowderPreparation

HTSC Wire Can Be Made!

A. Extrusion

B. Wire DrawC. RollingDeformation

& Processing3.

Oxidation -Heat Treat

4.

Billet Packing& Sealing

2.

But it’s 70% silver!

Finished Cable

Reading Assignment

1. Garwin and Matisoo, 1967 (100 GW on Nb3Sn)

2. Bartlit, Edeskuty and Hammel, 1972 (LH2, LNG and 1 GW on LTSC)

3. Haney and Hammond, 1977 (Slush LH2 and Nb3Ge)

4. Schoenung, Hassenzahl and Grant, 1997 (5 GW on HTSC, 1000 km)

5. Grant, 2002 (SuperCity, Nukes+LH2+HTSC)

6. Proceedings, SuperGrid Workshop, 2002

These articles, and much more, can be found at www.w2agz.com, sub-pages SuperGrid/Bibliography

1967: SC Cable Proposed!

100 GW dc, 1000 km !

“Hydricity” SuperCables

+v I-v

I

H2 H2

Circuit #1 +v I-v

I

H2 H2

Circuit #2

Multiple circuitscan be laid in single trench

HV Insulation

“Super-I nsulation”

Flowing LiquidHydrogen

Superconductor“Conductor”

DO

DH

Al

Al “core” of diameter DCwound with

HTSC tape ts

thick

HV Insulation

“Super-I nsulation”

Flowing LiquidHydrogen

Superconductor“Conductor”

DO

DH

Al

Al “core” of diameter DCwound with

HTSC tape ts

thick

SuperCable

Al

Al “core” of diameter DCwound with

HTSC tape ts

thickAl

Al “core” of diameter DCwound with

HTSC tape ts

thickAl

Al “core” of diameter DCwound with

HTSC tape ts

thickAl

Al “core” of diameter DCwound with

HTSC tape ts

thick

Power Flows

PSC = 2|V|IASC, where PSC = Electric power flowV = Voltage to neutral (ground)I = SupercurrentASC = Cross-sectional area of superconducting annulus

Electricity

PH2 = 2(QρvA)H2, where PH2 = Chemical power flow Q = Gibbs H2 oxidation energy (2.46 eV per mol H2)ρ = H2 Density v = H2 Flow Rate A = Cross-sectional area of H2 cryotube

Hydrogen

Power Flows: 5 GWe/10 GWth

0.383.025,000100,0005,000

tS (cm)DC (cm)HTS J C(A/cm2)

Current (A)

Power (MWe)

Electrical Power Transmission (+/ - 25 kV)

0.383.025,000100,0005,000

tS (cm)DC (cm)HTS J C(A/cm2)

Current (A)

Power (MWe)

Electrical Power Transmission (+/ - 25 kV)

45.34.76405,000

DH- actual (cm)

H2 Flow (m/s)

DH- eff ective (cm)

Power (MWth)

Chemical Power Transmission (H2 at 20 K, per "pole")

45.34.76405,000

DH- actual (cm)

H2 Flow (m/s)

DH- eff ective (cm)

Power (MWth)

Chemical Power Transmission (H2 at 20 K, per "pole")

Radiation LossesWR = 0.5εσ (T4

amb – T4

SC), where WR = Power radiated in as watts/unit areaσ = 5.67×10-12 W/cm2K4

Tamb = 300 KTSC = 20 Kε = 0.05 per inner and outer tube surfaceDH = 45.3 cm WR = 16.3 W/m

Superinsulation: WRf = WR/(n-1), where

n = number of layers = 10

Net Heat In-Leak Due to Radiation = 1.8 W/m 

Fluid Friction LossesWloss = M Ploss / ,

Where M = mass flow per unit length Ploss = pressure loss per unit length = fluid density

Fluid Re (mm) DH (cm) v (m/s) P

(atm/10 km)

Power

Loss (W/m)

H (20K) 2.08 x 106 0.015 45.3 4.76 2.0 3.2

Heat Removal

dT/dx = WT/(ρvCPA)H2, where dT/dx = Temp rise along cable, K/mWT = Thermal in-leak per unit Lengthρ = H2 Density v = H2 Flow RateCP = H2 Heat Capacity A = Cross-sectional area of H2 cryotube

SuperCable Losses (W/M) K/10km

Radiative Friction ac Losses Conductive Total dT/dx

1.8 3.2 1 1 7 10-2

SuperCable H2 Storage

Some Storage Factoids

Power (GW)

Storage (hrs) Energy (GWh)

TVA Raccoon Mountain 1.6 20 32

Alabama CAES 1 20 20

Scaled ETM SMES 1 8 8

One Raccoon Mountain = 13,800 cubic meters of LH2

LH2 in 45 cm diameter, 12 mile bipolar SuperCable = Raccoon Mountain

Relative Density of H2 as a Function of Pressure at 77 K wrt LH2 at 1 atm

0

0.2

0.4

0.6

0.8

1

1.2

0 2000 4000 6000 8000 10000

Pressure (psia)

Rh

o(H

2)/

Rh

o(L

H2)

Vapor

Supercritical

50% LH2

100% LH2

H2 Gas at 77 K and 1850 psia has 50% of the energy content of liquid H2

and 100% at 6800 psia

HV Insulation

“Super-I nsulation”

FlowingHigh PressureHydrogen Gas

Superconductor“Conductor”

DO

DH

Al

Al “core” of diameter DCwound with

HTSC tape ts

thick

Flowing liquid N2 cryogen in flexible tube, diameter DN

HV Insulation

“Super-I nsulation”

FlowingHigh PressureHydrogen Gas

Superconductor“Conductor”

DO

DH

Al

Al “core” of diameter DCwound with

HTSC tape ts

thick

Flowing liquid N2 cryogen in flexible tube, diameter DN

“Hybrid” SuperCable

Electrical Issues• Voltage – current tradeoffs

– “Cold” vs “Warm” Dielectric

• AC interface (phases)– Generate dc? Multipole, low rpm units (aka hydro)

• Ripple suppression– Filters

• Cryogenics– Pulse Tubes– “Cryobreaks”

• Mag Field Forces• Splices (R = 0?)• Charge/Discharge cycles (Faults!)• Power Electronics

– GTOs vs IGBTs– 12” wafer platforms– Cryo-Bipolars

Construction Issues• Pipe Lengths & Diameters (Transportation)• Coax vs RTD• Rigid vs Flexible?• On-Site Manufacturing

– Conductor winding (3-4 pipe lengths)– Vacuum: permanently sealed or actively pumped?

• Joints – Superconducting– Welds– Thermal Expansion (bellows)

Jumpstarting the SuperGrid

• Do it with SuperCables• Focus on the next two decades• Get started with superconducting dc

cable interties & back-to-backs using existing ROWs

• As “hydrogen economy” expands, parallel/replace existing gas transmission lines with SuperCables

• Start digging

Electricity Generation - June 2004

Coal49%

Oil2%Hydro

7%

Nukes20%

Gas18%

Renewable2%

Al-Can Gas Pipeline

Proposals

Mackenzie Valley Pipeline

1300 km

18 GW-thermal

Electrical Insulation

“Super-Insulation”

Superconductor

LNG @ 105 K1 atm (14.7 psia)

Liquid Nitrogen @ 77 K

Thermal Barrier to

LNG

LNG SuperCable

SuperCable Prototype Project

H2 e–

H2 Storage SMES

Cryo I/C Station

500 m Prototype

“Appropriate National Laboratory”2005-09

Regional System Interconnections