Super

Cable

Combined Storage & Delivery of Electricity & Hydrogen

RegionGrid Interconnection H2H2 e–e– H2H2 e–e– My RTO Your RTO 50 Miles FACTS/IC “Use Existing Overhead ROW” Hydrogen Tanker Truck Fueling

SuperCables +v I -v I H2H2 H2H2 Circuit #1 +v I -v I H2H2 H2H2 Circuit #2 Multiple circuits can be laid in single trench

LH 2 SuperCable HV Insulation “Super- Insulation” Superconductor Hydrogen DODO DH2DH2 t sc

Power Flows P SC = 2|V|IA SC, where P SC = Electric power flow V = Voltage to neutral (ground) I = Supercurrent A SC = Cross-sectional area of superconducting annulus Electricity P H2 = 2(QρvA) H2, where P H2 = Chemical power flow Q = Gibbs H 2 oxidation energy (2.46 eV per mol H 2 ) ρ = H 2 Density v = H 2 Flow Rate A = Cross-sectional area of H 2 cryotube Hydrogen

Electric & H 2 Power ,000100,000+/ Annular Wall Thickness (cm) Critical Current Density (A/cm 2 ) Current (A)Voltage (V)Power (MW) Electricity “Equivalent” Current Density (A/cm 2 ) H 2 Flow Rate (m/sec) Inner Pipe Diameter, D H2 (cm) Power (MW) Hydrogen (LH 2, 20 K)

H 2 - Gas SuperCable Electrical Insulation “Super- Insulation” Superconductor Supercritical 77 K 2000 – 7000 psia Liquid 77 K

H 2 Gas at 77 K and 1850 psia has 50% of the energy content of liquid H 2 and 100% at 6800 psia

SuperCable H 2 Storage Some Storage Factoids Power (GW) Storage (hrs)Energy (GWh) TVA Raccoon Mountain Alabama CAES120 Scaled ETM SMES188 One Raccoon Mountain = 13,800 cubic meters of LH2 LH 2 in 10 cm diameter, 250 mile bipolar SuperCable = Raccoon Mountain

Thermal Losses W R = 0.5εσ (T 4 amb – T 4 SC ), where W R = Power radiated in as watts/unit area σ = 5.67× W/cm 2 K 4 T amb = 300 K T SC = 20 K ε = 0.05 per inner and outer tube surface D SC = 10 cm W R = 3.6 W/m Radiation Losses Superinsulation: W R f = W R /(n-1), where n = number of layers Target: W R f = 0.5 W/m requires ~10 layers Other addenda (convection, conduction): W A = 0.5 W/m W T = W R f + W A = 1.0 W/m

Heat Removal dT/dx = W T /(ρvC P A) H2, where dT/dx = Temp rise along cable, K/m W T = Thermal in-leak per unit Length ρ = H 2 Density v = H 2 Flow Rate C P = H 2 Heat Capacity A = Cross-sectional area of H 2 cryotube Take W T = 1.0 W/m, then dT/dx = 1.89  K/m, Or, 0.2 K over a 10 km distance

Remaining Issues AC interface (12 phase) Ripple suppression –Filters –Cable impedance Charge/Discharge cycles Current stabilization via voltage control

Remaining Issues GTOs vs IGBTs 12” wafer platforms Cryo-Bipolars –Minority carrier concentration –Doping profiles –Computer simulation Power Electronic Discretes

Remaining Issues Safety Generation (high pressure electrolysis) Cryocoolers Liquid vs Pressurized Gas Flow Rate Losses Storage & Delivery Hydrogen Issues

SuperCable Prototype Project H2H2 e–e– H 2 Storage SMES Cryo I/C Station 500 m Prototype “Appropriate National Laboratory”

North American 21st Century Energy SuperGrid H2H2 e–e– H2H2 e–e– H2H2 e–e– H2H2 e–e– Commercial Residential BMW Z9 Heavy Industry Energy Storage Solar Roofs Urban Biomass HTGCR Nuclear Plant

A Vision Realized… “…an admirable work of science and patriotism.” Marquis de Lafayette …on first visiting the Erie Canal