Materials in high-temperature superconducting cables Dag Willén nkt cables Autonomous University of Barcelona 16 April 2008 1
Contents Background on superconductivity Materials in HTS cables Cost an industrial estimation Example: The HTS Triax Energy Cable Applications of HTS cables 2
Background on superconductivity 3
Discovery In the year 1911, by Kammerlingh Onnes Mercury lost its resistance as Helium was liquified Nobel price in Physics 1913 Material Al Hg Nb Pb Sn Ti Tc 1,2 K 4,2 K 9,26 K 7,2 K 3,7 K 0,39 K Nb 3 Sn V 3 Si (17,5 K) Nb 3 Ge (23 K) 4
Development 150 125 100 75 50 KCritical ritis k temperature m tur (K[K] e lvin) HgBaCaCuO (133 K) T lbacacuo Bi-2223 YBCO J. Georg Bednorz and K. Alexander Müeller, IBM Zürich, La-Cu-Oxide, HTS ~30 K, 1986, Nobel price physics 1987 Paul Chu, Univ. Houston, YBCO, 1987, ~90 K 25 0 Nb3Sn Hg Nb 1900 1920 1940 1960 1980 2000 Årstal year 5
February 1995 6
Materials in HTS cables 7
epitaxy Grain boundaries buffer layers HTS layers mech. strength synthesis ageing/pd chem. protection metals ceramics stabilizer creep length SC high voltage AC loss BD strength materials in large currents pressure HTS cables joints regulations thermal modelling safety vacuum insulation cryogenic temperatures spacers super-insulation welding getter materials cooling tech solid state cooling? wear fluid dynamics thermal shrinkage brittleness 8
Synthesis 1G HTS 0.3 mm 4.5 mm 9
Properties of 1G HTS 3.0E-08 ASC tape (warm-up) Ic(77K) = 200 A 2.5E-08 ρ [Ωm] 2.0E-08 1.5E-08 1.0E-08 3.5 5.0E-09 0.0E+00 3 50 100 150 200 250 300 2.5 T [K] ρ Temperature dependence of BSCCO Young data @ 0-T Young data @ 0.1 T Grabovicki data of NST Grabovickic data @ 0-T y = 7.16-0.115T + 0.000455T 2 I c (T) / I c (77 K) 2 1.5 Tc = 110 K 1 0.5 0 40 50 60 70 80 90 100 110 T (K) 10
Synthesis 2G HTS Example: Buffer Layer by Ion Beam Assisted Deposition (IBAD) Pilot HTS SuperPower Inc. Example: HTS Layer by Metal Organic Chemical Vapor Deposition (MOCVD) 11
Suppliers Company: SuperPower Inc. AMSC EAS/EHTS Theva SEI Fujikura Buffer layer IBAD Rabits IBAD ISD Rabits IBAD HTS layer MOCVD MOD PLD Thermal evaporation PLD PLD Rabits = Rolling-Assisted BI-axially Textured Substrate (cold-rolled and annealed Ni-W alloy) MOD = Metal Organic Deposition (slot-die coating of trifluoroacetate-based precursors) ISD = Inclined Substrate Deposition 12
Status, 2G 1000 100 10 100 1000 Length (meters) 13 100,000 50,000 10,000 A-m 1,000,000 500,000 Critical current s.f. 77K (A/cm-width) Short samples 2006 Goal HTS cable req. DOE Target
Cost an industrial estimation 14
Materials costs USD/kg 3,5 3 2,5 2 1,5 USD/kg 1 0,5 0 PE Pb Al Cu Examples from 2005, USD 15
Conductor cost - copper A Single core 80 70 60 L = 1 m Cost [$/kam] 50 40 30 20 10 Single core [A] Segmented core [A] A Segmented core 0 500 1000 1500 2000 2500 Ampacity [A] Examples from 2005, USD 16
1G cost Brass (Cu + Zn) Solder (Sn + Pb) Sheath (Ag-alloy) Matrix (Ag) HTS filaments (BSCCO) Examples from 2005, USD 17
1G materials cost USD/kg 1000 100 10 1 0,1 PP PE Fe Zn Sn Ni Ag HTS *Spot prices at LME, Comex and other sources Examples from 2005, USD 18
1G tape cost Brass 1,0% Solder 0,4% BSCCO in Ag tube Brass reinforcement 0.38 mm x 4.3 mm HTS fill factor 0.43 J c =40 000 A/cm 2 I c =152 A/tape J e =92 A/mm 2 Ag cost 226 $/kg HTS 24,7% Silver 73,9% The raw materials cost at 5% scrap is 11 USD/kAm (1.7 USD/m) Examples from 2005, USD 19
1G factory cost Small-scale Capacity 600 km/yr x 100 A 8 M$ investment/20 yrs Bluecollar 10 people x 40 k$/yr salary 50% operation cost Whitecollar 1 Manager 1 sales force 4 R&D 6 x 83 k$/yr + 25% expenses Overhead 1 administration 1 x 40 k$/yr + 25% expenses Cost 28 $/kam @ 100% utilization Large-scale production Capacity 10000 km/yr x 150 A 50 M$ investment/20 yrs Bluecollar 15 people x 25 k$/yr salary 50% operation cost Whitecollar 3 Manager 4 sales force 5 R&D 12x100 k$/yr + 25% expenses Overhead 2 administration 2 x 25 k$/yr + 25 % expenses Cost 3 $/kam @ 100% utilization Examples from 2005, USD 20
1G tape cost (utilization & scrap) 240 210 Price level spring 2005 180 150 2008 210-240 180-210 Cost [$/kam] 120 90 150-180 120-150 90-120 60 30 60-90 30-60 0-30 0 10% 30% Utilization 50% 70% 90% 110% 5% 90% 60% Scrap 30% Examples from 2005, USD 21
2G cost Brass (Cu + Zn) Solder (Sn + Pb) Protection layer (Ag) HTS layer (YBCO) Substrate (Ni + 5-10% W) Examples from 2005, USD 22
2G tape cost YBCO on 50 µm Ni substrate 70 µm brass reinforcement Ni 8% Brass 2% Solder 2% 10 µm Ag protection layer 0.18 mm x 4.3 mm HTS fill factor 0.12 J c =350 000 A/cm 2 I c =151 A/tape HTS 26% Silver 62% J e =193 A/mm 2 The materials cost at 5% scrap is 2.27 USD/kAm (0.36 USD/m) Examples from 2005, USD 23
2G tape cost (utilization & scrap) 240 210 Cost [$/kam] 180 150 120 90 60 30 Announced entry-level pricing 2008-2009 210-240 180-210 150-180 120-150 90-120 60-90 30-60 0-30 0 10% 30% 50% Utilization 70% 90% 5% 110% 30% 60% 90% Scrap Examples from 2005, USD 24
HTS cost projection IV Supra, 2008 25
Example: The HTS Triax Energy Cable 26
New technology? nkt cables has 9 years of operation experience! Copenhagen, Denmark 30 m, 30 kv, 104 MW 2 years operation 2001-2003 Supplied 50,000 users Carrollton, GA, U.S.A 30 m, 12.5 kv, 27 MW 6 years operation 2000 2006 Supplied energy to Southwire s cable factories Columbus, OH, U.S.A.Type tested 2005 200 m, 13 kv, 69 MW Installed and commissioned 2006 Operating since 8 Aug 2006 Σ = 9 years 27
New: HTS Triax Energy Cable Suitable for medium voltages (10-72 kv) Former Dielectric Dielectric Dielectric LN Cryostat LN Phase 1 HTS Phase 2 HTS Phase 3 HTS Copper Neutral 28
Terminations 3 Phase Connections Neutral Connection Three-phase terminations Vertical insulators 29
Splice in underground vault Cable was cut in two pieces Three-phase splice 30
Cooling system Cooling machines have become 1/3 of the size compared to that of 5 years ago 4 m 7 m 9 m 31
Type tested XLPE standards IEC-60840 IEEE 400.2 ICEA S-94-649-2000 Fluid-filled standards IEC-141-1, 141-4 AEIC CS-1-90 Accessories IEC-61462 IEEE-48-1996 Applicable parts (HV testing, load testing, pressure) Additional tests (Cryogenic) 32
Applications of HTS Energy Cables 33
Applications & Benefits MV HTS Triax Energy Cable Improved performance and functionality Long-distance HV transmission Commercial now! Reference: 200 m in Columbus, OH Reference: 1.7 km in New Orleans ~1 year Reference: 300 m in New York Feasibility study: 6 km in Amsterdam 4-5 years Feasibility study: 1 GW @ 150 kv 100-300 km 34
Reference: 200 m Columbus, OH Energized: 8 Aug 2006 Date: 8 Aug 2007 Time since start: 8756 h/365 d Time in operation: 8752 h/365 d Cable outings: 1 Service outings: 0 Scheduled outings: 1 Failures: 0 Availability: 99.95% Min Power: 18 MW Max Power: 58 MW Ave Power: 30 MW Transmitted energy: 264 GWh 35
Reference: 1.7 km New Orleans 13 kv HTS Triax 64 MVA Replaces a 220 kv line and thehv sectionofa transformer substation Labarre HV substation 230 kv XLPE HTS Triax Energy Cable Metaire Metaire HV MV substation substation 230 kv system HTS Triax system Cable system Labarre station Metaire station Contigency 36
Applications & Benefits MV HTS Triax Energy Cable Improved performance and functionality Long-distance HV transmission Commercial now! Reference: 200 m in Columbus, OH Reference: 1.7 km in New Orleans ~1 years Reference: 300 m in New York Feasibility study: 6 km in Amsterdam 4-5 years Feasibility study: 1 GW @ 150 kv 100-300 km 37
Reference: 300 m New York City New functionality: HTS cables have the inherent ability to limit fault currents Voltage [kv] Nominal voltage limited fault current unlimited fault current Zero voltage nominal current Critical current Current [ka] 38
Reference: 300 m New York City HV 110-230 kv HV 110-230 kv MV distribution 10-20 kv HTS Triax FCL Cable MV distribution 10-20 kv Station-to-station tie on low side of Transformers Can carry full station load at MV Share transformer redundancy between distribution stations Increase transformer asset utilization Increased reliability and resilience 39
Feasibility: 6 km in Amsterdam Gas Pressure Cable HTS Triax Energy Cable 40
Feasibility: 6 km in Amsterdam 150 kv NDK Low-impedance transformer 2 x XLPE 200 MVA 50 kv HK 50 kv 200 MVA 1 x HTS Triax FCL Cable 250 MVA Power to city center Retrofit save digging cost Low impedance stable voltage Low losses power through HTS Limited fault current N+2 redundancy 41
Applications & Benefits MV HTS Triax Energy Cable Improved performance and functionality Long-distance HV transmission Commercial now! Reference: 200 m in Columbus, OH Reference: 1.7 km in New Orleans ~1 years Reference: 300 m in New York Feasibility study: 6 km in Amsterdam 4-5 years Feasibility study: 1 GW @ 150 kv 100-300 km 42
HTS Coax High-Voltage Cables Same materials and machinery Suitable for higher voltages, 50-150 kv Dielectric Neutral Ph1 Ph2 Ph3 43
Transmission length HTS cables resemble OH lines electrically 400 kv XLPE 150 kv HTS 50 kv Triax Active power Reactive power Energy to customer [MW] 1000 Cu HTS Coax Cable 500 HTS Triax 50 200 300 Distance [km] Reactive power -500 [MVAr] 44
Example 4: 150 km, 2 GVA Alt 1: 400 kv OH + UG Reactive power Stability Visibility Load center OH line UG Cable HTS cable Alt 2: HVDC Expensive converters Difficult to connect underway Need parallel AC system AC/DC DC/AC Alt 3: HV HTS Energy Cable Invisible & efficient Serves the local communities SUPER GREEN 45
Conclusion 1. Materials Many interesting aspects 2. Cost comes down with increasing maturity 3. Applications: First commercial product available Imroved properties (reduced loss) and functionality (FCL) Great potential in transmission 46
Thank you! 47