Superconductivity -- The Future of Power Delivery ?? EPRI TGIF September 28, 2001 Steve Eckroad, Paul Grant & Ray Lings

What is Superconductivity? Simply put: Superconductivity is the complete absence of resistance to the flow of electricity in a conductor

What is Superconductivity? All materials have electrical resistance - some more than others For many materials, their resistance decreases with decreasing temperature But, at a certain temperature (very low) the resistance disappears altogether!

Superconductivity for Power Phenomenon known for almost a century Until recently, non-power applications were only feasible use In the last decade research has opened up the possibility of electric power use of superconductivity Key discovery was “high temperature superconductivity” --> “HTS”

Characteristics of Superconductors Carry large currents with no DC losses AC losses minimized by design and material choice Physically small Very high current densities reduce material requirements Operate at cryogenic temperatures Enclosure provides environmental isolation Limited commercial production today

EPRI’s HTS Cable Project Initial vision Challenges Project history Current Status Vision for future

HTS Cable Timeline 1987: High temperature superconductivity (HTS) announced 1996: EPRI & DOE test a 50-meter HTS conductor manufactured by Pirelli with ASC wire (SPI-Phase I) 1990: EPRI-patented warm dielectric HTS cable design 1987 1990 1993 1996 1999 2001 1989: EPRI begins R&D to develop HTS power cables for utilities 1998: DOE SPI-Phase II award: Detroit Edison demonstration of warm dielectric cable ($5.5M) 1993: Pirelli “fleshes out” EPRI cable design 2001: First Utility HTS Cable Commissioned at Detroit Edison

Project Participants Pirelli Cables & Systems (PC&S): “Cable System provider” (also Team Leader & Project Manager) Detroit Edison Co (DTE): “Utility End User”, Test Site provider American Superconductor Corporation (ASC): “HTS Tape provider” Lotepro Corporation: “Refrigeration System provider” EPRI (Electrical Power Research Institute): “Utilities Group expertise, systems studies” US Department of Energy: “Program Sponsor”

Project Objectives Design, install and operate a 24 kV, 3-phase, 100MVA warm dielectric HTS cable system at Detroit Edison Demonstrate long term operation in “real life” conditions to prove reliability and gain experience

Project Deliverables Design and fabrication of 24 kV HTS cable system Delivery to Detroit of cable, accessories and auxiliary equipment Installation and commissioning of cable system

Detroit’s Frisbie Substation & Cable Route Project Description Detroit’s Frisbie Substation & Cable Route

Cable Route, Cont’d. Nitrogen Refrigeration 120 to 24 kV Transformer

HTS Cable Structure Liquid N2 Refrigerant Operates at -200°C BSCCO (Bi2Sr2Ca2Cu3O10) HTS Tape Liquid N2 Refrigerant Operates at -200°C

HTS Cable

Liquid Nitrogen Circuit Diagram Phase X Phase Y Phase Z T1 T2 T3 T5 T4 T6 Refrigerator

Cable Installation Successful! Nine copper cables replaced by three superconducting cables Cable successfully installed without significant performance degradation Installation by DECo & Pirelli crews Video courtesy of ASC & Paul Grant

Status Cable and refrigeration system installation completed September 2001 Pumping on cryostat began in September Cable to be commissioned November 2001

Status, Cont’d. EPRI Patent on cable design granted August 2001 EPRI/DECO sponsored Visitor Center at site opened and displays finished

Issues/Concerns Will cable work? (It should …) Continuous pumping on cable not cost-effective: hermetically sealed design needed Need demonstration of alternate cable designs for high voltage transmission Will there be large enough supply of HTS wire?

Applications and Opportunities for HTS Cables Densely Populated Load Centers Higher Transfer Capability through Existing Infrastructure “Virtual” Substations Underground High Capacity Feeds Non-traditional Generator Siting Practices Transmission at Generator Voltages Reduced Project Planning Period (Underground vs Overhead) System Upgrades Load Flow Improvements and Circuit Reinforcement Remove Transmission Constraints for Economic Generation Dispatch Overload Capability without Loss of Life

Electricity Technology Roadmap “We must reverse current trends and make a renewed commitment to energy R&D.” Kurt Yeager CEO, EPRI 29 October 1999 NPC Speech

A Power Delivery Vision For The Future Superconducting cables in urban locations All superconducting substations Continental superconducting power grid Large scale energy storage with superconducting magnets Closed-loop hydrogen systems incorporating renewable nuclear power, superconducting transmission and substations, distributed fuel cells and hydrogen storage

The All Superconducting Substation Substation comprised of (mostly) all superconducting power components Transformer, Cable & Bus, Fault Current Limiter, SMES Single Cryostation Support “Full 4-Quadrant” Power Uninterruptible Substation Power (superconducting generator?)

Four Powerful Motives ... … For the All Superconducting Substation Environment Energy efficiency Space Operating cost & life

Superconducting Substation Advantages Insensitive to environmental variations — particularly elevated temperatures Reduced personnel and equipment hazard: Fewer exposed parts (e.g., bushings) Fewer arcs and other failures associated with environmental conditions Less exposure to lightning Reduced impact on the environment No oil spills Reduced fire hazard

Superconducting Substation Advantages - II Can accommodate more power in a given area Can handle more power at a given maximum voltage Will be more efficient (lower losses) Will have fewer mechanical systems because of enclosure and integration of components

Superconducting Substation Disadvantages Superconducting components are not available today. Cost for initial units will be high Superconducting systems will have an inherent learning curve. But, no long term technical disadvantages anticipated

The Path to Superconducting Substations Superconducting substations will be used to replace conventional substations where: Additional power demands must be met at an existing site. Existing cables must be upgraded and superconducting cables are to be used to increase capacity Transformer life is reduced due to extensive overload conditions Component life is short due to environmental conditions

The Path to Superconducting Substations - II Nearterm impact will be small - will initially fill niche markets Will first be installed where one or more superconducting device is required and the effectiveness of multiple components is apparent. First commercial devices---superconducting cables and transformers---will become available in 3 to 5 years. These devices must be used independently to obtain confidence and to assure operational integrity

Powering the 21st Century Looking Further Out ... Large-scale superconducting transmission systems Use of superconducting magnets for bulk storage (SMES) Novel “closed-loop” energy/delivery systems using superconducting system synergies

Continental Superconducting Superhighway

The Ideal Energy Infrastructure Safe, “renewable,” nuclear fission power “Pebble”-based, He cooled Fuel reprocessing to capture actinide cycle “All-Superconducting” electric power generation and delivery Cables, transformers, storage The “hydrogen economy” realized Cryogen for superconductivity End-use thermal energy

Industrial/Residential A Closed Loop System “Laguna Genome” An emission-free Industrial/Residential community Escuelas Casas Lagunas H2 El coche de la familia O2 Energia Durango, SSA H H MgB2 Renewable Nuclear Hydrogen dc Superconductivity CyroEnergy DNA-to-order.com Supermercado