Basic Research Needs for Superconductivity. Report of the Basic Energy Sciences Workshop on Superconductivity, May 8-11, 2006

TLDR: Superconductivity offers powerful new opportunities for restoring the reliability of the power grid and increasing its capacity and efficiency as discussed by the authors, which is the most complex artificial system ever built and may be the greatest engineering achievement of the 20th century.

Abstract: As an energy carrier, electricity has no rival with regard to its environmental cleanliness, flexibility in interfacing with multiple production sources and end uses, and efficiency of delivery. In fact, the electric power grid was named ?the greatest engineering achievement of the 20th century? by the National Academy of Engineering. This grid, a technological marvel ingeniously knitted together from local networks growing out from cities and rural centers, may be the biggest and most complex artificial system ever built. However, the growing demand for electricity will soon challenge the grid beyond its capability, compromising its reliability through voltage fluctuations that crash digital electronics, brownouts that disable industrial processes and harm electrical equipment, and power failures like the North American blackout in 2003 and subsequent blackouts in London, Scandinavia, and Italy in the same year. The North American blackout affected 50 million people and caused approximately $6 billion in economic damage over the four days of its duration. Superconductivity offers powerful new opportunities for restoring the reliability of the power grid and increasing its capacity and efficiency. Superconductors are capable of carrying current without loss, making the parts of the grid they replace dramatically more efficient. Superconducting wires carry up tomore » five times the current carried by copper wires that have the same cross section, thereby providing ample capacity for future expansion while requiring no increase in the number of overhead access lines or underground conduits. Their use is especially attractive in urban areas, where replacing copper with superconductors in power-saturated underground conduits avoids expensive new underground construction. Superconducting transformers cut the volume, weight, and losses of conventional transformers by a factor of two and do not require the contaminating and flammable transformer oils that violate urban safety codes. Unlike traditional grid technology, superconducting fault current limiters are smart. They increase their resistance abruptly in response to overcurrents from faults in the system, thus limiting the overcurrents and protecting the grid from damage. They react fast in both triggering and automatically resetting after the overload is cleared, providing a new, self-healing feature that enhances grid reliability. Superconducting reactive power regulators further enhance reliability by instantaneously adjusting reactive power for maximum efficiency and stability in a compact and economic package that is easily sited in urban grids. Not only do superconducting motors and generators cut losses, weight, and volume by a factor of two, but they are also much more tolerant of voltage sag, frequency instabilities, and reactive power fluctuations than their conventional counterparts. The challenge facing the electricity grid to provide abundant, reliable power will soon grow to crisis proportions. Continuing urbanization remains the dominant historic demographic trend in the United States and in the world. By 2030, nearly 90% of the U.S. population will reside in cities and suburbs, where increasingly strict permitting requirements preclude bringing in additional overhead access lines, underground cables are saturated, and growth in power demand is highest. The power grid has never faced a challenge so great or so critical to our future productivity, economic growth, and quality of life. Incremental advances in existing grid technology are not capable of solving the urban power bottleneck. Revolutionary new solutions are needed ? the kind that come only from superconductivity.« less

Figures

Figure 15 The contrast between the normal and superconducting state of electrons is somewhat similar to the disordered crowd (left panel) and the highly coordinated motion of marching soldiers (right panel).

Figure 11 Left panel: Magnetic field dependence of Jc in a high-quality YBCO-coated conductor, at the benchmark temperature of 77 K, the boiling point of liquid N2 (red dots). The requirements for devices (green boxes) clearly exceed present performance at this temperature. The solid blue line is the highest possible Jc that could be achieved in YBCO based on fundamental physical limits. Nanoengineering of the vortex pinning landscape could result in a revolutionary increase of performance by a factor of 5–10, up to this limit. The dashed green line is the theoretical limit for Jc attainable in a hypothetical next-generation superconducting wire with Tc = 120 K. Right panel: The temperature dependence of Jc at zero magnetic field.

Figure 24 The observed superconducting transition temperature (Tc) of a variety of classes of superconductors is plotted as a function of time. Recent discoveries have increased the highest-observed Tc in a number of materials to unprecedented levels, such as in heavy fermion (PuCoGa5), carbon nanotubes (CNTs), and graphite intercalated compounds (CaC6).

Figure 3 Performance levels of prototype 2G conductors (May 2006). The metric plotted is the critical current per unit width of tape (A/cm-w), measured at 77 K in self field. As piece-lengths increase, the current levels decrease, a problem that needs to be solved when approaching the indicated DOE goals. The inset identifies the research organization on the left and the fabrication method on the right.

Figure 9 Experimental approaches to test the order parameter symmetry in the cuprates. Left panel: A corner junction SQUID. Right panel: half-flux quantum detected at the meeting point of a tri-crystal sample.

Figure 19 Schematic comparison of the 3x3 duct bank of an underground copper distribution system compared to one triax HTS cable operating at 13kV and transferring 69 MVA of power.

Full text

On the Cover:
Superconductivity is one of nature's most exotic phenomenon; the complete loss of
electrical resistance in certain materials when they are cooled to a low temperature. The
loss-free circulation of superconducting currents also underlies key technological
applications. For instance, intense magnetic fields are generated by coils of
superconducting wires for medical magnetic resonance imaging. Only when cooled close
to absolute zero of temperature (−273°C) do such metals and alloys become
superconducting.
A revolution took place 20 years ago when entirely new families of superconductors
based on ceramic oxides were discovered. These work at much higher temperatures. The
current high-temperature superconductor HgBa
2
Ca
2
Cu
3
O
8
is the record holder. It operates
at temperatures as high as 164 K (−109°C). The crystal structure (on the front cover) of
this complex oxide allows the electrical current to travel easily along certain crystal
planes, which leads to superconductivity at these remarkably high temperatures.
Grand Challenges include the discovery of a room-temperature superconductor and
unraveling its mechanism.
Diagram courtesy of Professor Peter P. Edwards and Dr. Martin O. Jones, Inorganic
Chemistry Laboratory, Oxford University, England.
http://www.chem.ox.ac.uk/researchguide/ppedwards.html

BASIC RESEARCH NEEDS FOR SUPERCONDUCTIVITY
Report on the Basic Energy Sciences Workshop
on
Superconductivity
Chair: John Sarrao, Los Alamos National Laboratory
Co-chair: Wai-Kwong Kwok, Argonne National Laboratory
Panel Chairs:
Materials Ivan Bozovic, Brookhaven National Laboratory
Theory Igor Mazin, Naval Research Laboratory
Phenomena J.C. Seamus Davis, Cornell University
Leonardo Civale, Los Alamos National Laboratory
Applications David Christen, Oak Ridge National Laboratory
Office of
Basic Energy
Sciences Contact: James Horwitz, Basic Energy Sciences, U.S. Department of Energy
Special Assistance
Technical: Gary Kellogg, Sandia National Laboratories
Douglas Finnemore, Ames Laboratory
George Crabtree, Argonne National Laboratory
Ulrich Welp, Argonne National Laboratory
Administrative: Christie Ashton, Basic Energy Sciences, U.S. Department of Energy
Brian Herndon, Oak Ridge Institute for Science and Education
Leslie Shapard, Oak Ridge Institute for Science and Education
Publication: Renée M. Nault, Argonne National Laboratory
This report is available on the web at http://www.sc.doe.gov/bes/reports/files/SC_rpt.pdf.

ii

iii
CONTENTS
Notation .................................................................................................................................................. v
Executive Summary................................................................................................................................ ix
Introduction............................................................................................................................................. 1
Broader Impact of Superconductivity..................................................................................................... 11
Grand Challenges.................................................................................................................................... 17
Reports of the Panels on Basic Research Needs for Superconductivity ................................................. 25
Basic Research Challenges for Applications ............................................................................. 27
Basic Research Challenges for Vortex Matter........................................................................... 43
Basic Research Challenges for Superconductivity Theory........................................................ 61
Basic Research Challenges for New Phenomena ...................................................................... 69
Basic Research Challenges in Superconducting Materials ........................................................ 85
Priority Research Directions ................................................................................................................... 97
Pursue Directed Search and Discovery of New Superconductors ............................................. 99
Control Structure and Properties of Superconductors Down
to the Atomic Scale ............................................................................................................. 103
Maximize Current-carrying Ability of Superconductors with Scalable
Fabrication Techniques ....................................................................................................... 109
Understand and Exploit Competing Electronic Phases.............................................................. 117
Develop a Comprehensive and Predictive Theory of Superconductivity
and Superconductors ........................................................................................................... 121
Identify the Essential Interactions that Give Rise to High T
c
Superconductivity ...................... 125
Advance the Science of Vortex Matter...................................................................................... 129
Cross-Cutting Research Directions......................................................................................................... 135
New Tools to Integrate Synthesis, Characterization, and Theory.............................................. 137
Enabling Materials for Superconductor Utilization................................................................... 141
Conclusion .............................................................................................................................................. 145
Appendix 1: Current State of Research................................................................................................... 151
Introduction and Overview ........................................................................................................ 157
Superconducting Materials ........................................................................................................ 160
Phenomenology of High Temperature & Exotic Superconductivity ......................................... 171
Vortex Phenomena..................................................................................................................... 183
Theory........................................................................................................................................ 193
Energy Related Applications for Superconductors.................................................................... 212
Appendix 2: Workshop Participants ....................................................................................................... 221
Appendix 3: Workshop Program ............................................................................................................ 227

Frequently asked questions

Q1. What contributions have the authors mentioned in the paper "Basic research needs for superconductivity" ?

In this paper, a complete determination of all relevant electronic and magnetic susceptibilities ( the electronic `` genome '' of high-temperature superconductivity can now be achieved for the first time. 

Q2. What is the purpose of superconducting reactive power regulators?

Superconducting reactive power regulators further enhance reliability by instantaneously adjusting reactive power for maximum efficiency and stability in a compact and economic package that is easily sited in urban grids. 

Q3. What is the purpose of this article?

Superconductivity offers powerful new opportunities for restoring the reliability of the power grid and increasing its capacity and efficiency. 

Q4. What is the role of superconducting in the grid?

By 2030, nearly 90% of the U.S. population will reside in cities and suburbs, where increasingly strict permitting requirements preclude bringing in additional overhead access lines, underground cables are saturated, and growth in power demand is highest. 

Q5. what is the name of the paper?

In fact, the electric power grid was named “the greatest engineering achievement of the 20th century” by the National Academy of Engineering. 

Q6. what is the physics of superconducting materials?

the growing demand for electricity will soon challenge the grid beyond its capability, compromising its reliability through voltage fluctuations that crash digital electronics, brownouts that disable industrial processes and harm electrical equipment, and power failures like the North American blackout in 2003 and subsequent blackouts in London, Scandinavia, and Italy in the same year. 

Q7. What is the important aspect of superconducting transformers?

Their use is especially attractive in urban areas, where replacing copper with superconductors in power-saturated underground conduits avoids expensive new underground construction. 

Q8. What is the name of the paper?

103 Maximize Current-carrying Ability of Superconductors with Scalable Fabrication Techniques ....................................................................................................... 109 Understand and Exploit Competing Electronic Phases.............................................................. 

Q9. What is the difference between superconducting and conventional transformers?

Not only do superconducting motors and generators cut losses, weight, and volume by a factor of two, but they are also much more tolerant of voltage sag, frequency instabilities, and reactive power fluctuations than their conventional counterparts.