The SuperCable:Dual Delivery of Chemical and Electric Power
Paul M. GrantEPRI Science Fellow (retired)
IBM Research Staff Member EmeritusPrincipal, W2AGZ Technologies
2004 SuperGrid 225 - 27 October 2004, Urbana, Il
Technical Plenary Session – Levis Faculty Center -- UIUCMonday, 25 October 2004, 9:30 AM
+ +
+ +•e-
+ +
+ +•e-
Superconductivity 101Cooper Problem
•
•
2∆
single particles
pairs
eikr1
e-ikr2
H(k) + H(-k) + V(k)
V(k) = -V0 0 k f dk eik(r1 - r2)
ψ(r1-r2) = φ(r1-r2)χ(s1,s2)
2∆ ∼ e-2/N(Ef)V0
Fermion-Boson Feynman Diagram
q
k1
k'1
k2
k'2
)/1exp( 14.1 λθ −= DCT
(Niobium) K 5.9,28.0
,K 275
=∴==
C
D
Tλθ
)/1exp( 14.1 λθ −= DCT
(Niobium) K 5.9,28.0
,K 275
=∴==
C
D
Tλθ
•-•eeee
GLAG
G d rm
i e A i e A a b[ ] [*
( * ) *( * ) * * *]φ φ φ φφ φφ φφ≈ − ∇ + ∇ + + +∫ 3 12
12
− ∇ − + − =
∇× ∇× + ∇ − ∇ + =
==
=
( ) ( )( ) ( )
(| | )( / )
/
* *
i f f fi f f f f f
a b fA
L
∂
κ
φπξ
κ λ ξ
A
A A
A
2 2
2 12
2
12
0
1 00
2Φ
The Flavors of Superconductivity
1/4π
HC1H
-M
Meissner
HC1
Normal
TCTemperature
Mag
netic
Fie
ld
λ < ξType I
The Flavors of Superconductivity
1/4π
HC1H
-M
Meissner
HC1
Normal
TCTemperature
Mag
netic
Fie
ld
HC2
HC2
Mixed
λ > ξType II
The Flavors of Superconductivity
1/4π
HC1H
-M
Meissner
HC1
Normal
TCTemperature
Mag
netic
Fie
ld
HC2
HC2
Mixed
λ > ξType II
NOTPERFECT
CONDUCTOR!
IrreversibilityLineIrreversibilityLine
Meissner
HC1
Normal
TCTemperature
Mag
netic
Fie
ld
HC2
Mixed
The Flavors of Superconductivity
R = 0
R ≠ 0
Meissner
HC1
Normal
TCTemperature
Mag
netic
Fie
ld
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
/cm
)
E = aJn
n = 15
T = 77 KHTS Gen 1
E = 1 µV/cm
TC vs Year: 1991 - 2001
1900 1920 1940 1960 1980 20000
50
100
150
200Te
mpe
ratu
re, T
C (K
)
Year
Low-TC
Hig
h-T C
164 K
MgB2
Oxide Powder Mechanically Alloyed Precursor1. Powder
Preparation
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!
Reading Assignment1. 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
“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-Insulation”
Flowing LiquidHydrogen
Superconductor“Conductor”
DO
DH
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
HV Insulation
“Super-Insulation”
Flowing LiquidHydrogen
Superconductor“Conductor”
DO
DH
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
SuperCable
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
Power FlowsPSC = 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
HV Insulation
“Super-Insulation”
Flowing LiquidHydrogen
Superconductor“Conductor”
DO
DH
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
HV Insulation
“Super-Insulation”
Flowing LiquidHydrogen
Superconductor“Conductor”
DO
DH
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
Power Flows: 5 GWe/10 GWth
0.383.025,000100,0005,000
tS (cm)DC (cm)HTS JC(A/cm2)
Current (A)
Power (MWe)
Electrical Power Transmission (+/- 25 kV)
0.383.025,000100,0005,000
tS (cm)DC (cm)HTS JC(A/cm2)
Current (A)
Power (MWe)
Electrical Power Transmission (+/- 25 kV)
45.34.76405,000
DH-actual (cm)
H2 Flow (m/s)
DH-effective (cm)
Power (MWth)
Chemical Power Transmission (H2 at 20 K, per "pole")
45.34.76405,000
DH-actual (cm)
H2 Flow (m/s)
DH-effective (cm)
Power (MWth)
Chemical Power Transmission (H2 at 20 K, per "pole")
Radiation LossesWR = 0.5εσ (T4
amb – T4SC), 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 / ρ ,
Where M = mass flow per unit lengthPloss = pressure loss per unit lengthρ = fluid density
2.0
∆P (atm/10 km)
3.24.7645.30.0152.08 x 106H (20K)
PowerLoss (W/m)
v (m/s) DH (cm)ε(mm)ReFluid
Heat RemovaldT/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
K/10kmSuperCable Losses (W/M)
10-27113.21.8
dT/dxTotalConductiveac LossesFrictionRadiative
SuperCable H2 Storage
32201.6TVA Raccoon Mountain
20201Alabama CAES
881Scaled ETM SMES
Energy (GWh)Storage (hrs)Power (GW)
Some Storage Factoids
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 10000Pressure (psia)
Rho
(H2)
/Rho
(LH2
)
Vapor
Supercritical
50% LH2
100% LH2
H2 Gas at 77 K and 1850 psia has 50% of the energy content of liquid H2and 100% at 6800 psia
HV Insulation
“Super-Insulation”
FlowingHigh PressureHydrogen Gas
Superconductor“Conductor”
DO
DH
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
Flowing liquid N2 cryogen in flexible tube, diameter DN
HV Insulation
“Super-Insulation”
FlowingHigh PressureHydrogen Gas
Superconductor“Conductor”
DO
DH
Al
Al “core” of diameter DCwound with
HTSC tape tsthick
Flowing liquid N2 cryogen in flexible tube, diameter DN
“Hybrid” SuperCable
Electrical Issues• Voltage – current tradeoffs• AC interface (phases)• Ripple suppression• 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
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