The scientific community was abuzz this week with the purported development of a material capable of room-temperature superconductivity, dubbed by its Korean researchers, as LK-99. At the time of this report, it appears scientific efforts to replicate the results of their paper¹ have not been successful. Don’t make that face. It’s a big deal. This would be one of the most important discoveries since the effective harnessing of electricity itself.

WHY ROOM-TEMPERATURE SUPERCONDUCTIVITY IS A SCIENTIFIC HOLY GRAIL

To understand why we get excited about room-temperature superconductivity you have to understand one of the fundamental aspects of electricity called resistance. Electricity passes through all materials and due to their physical makeup, resist the flow of current to some degree. Broadly, there are conductors and insulators. Conductors offer little resistance and can pass the electrical energy easily. Most metals fall into this category with some of the best being silver, gold, copper and aluminum. Insulators present a high degree of resistance and restrict the flow of electrons preventing the passage of electricity through them, including substances such as rubber, paper, glass, wood and common plastics.

Resistance is measured in ohms, named after the German physicist Georg Simon Ohm (1784-1854) who studied the dynamics between voltage, current and resistance. If you remember your high school physics, it was called Ohm’s Law. Resistance, even in conductors is not perfect and can result in energy loss. The general framework says, the higher the resistance, the lower the current. The most common byproduct of this loss of transferred energy is heat. Adding insult to injury, as heat increases, energy transfer is further reduced. Thus, moving energy is always fraught with the peril of losing energy and generating unwanted heat which can damage the infrastructure used to deliver this energy.

This matters because the further one is from the origin of the electricity being generated, the more loss occurs and more fuel must be expended to maintain the current. This is of great concern when fossil fuels are the primary source of energy production and greenhouse gases one of their primary operating and environmental challenges.

While material resistance is generally considered to be a negative factor in electrical energy propagation, it was integral in the generation of light in pre-LED technologies by heating a filament in a lightbulb until it glowed brightly. Your toaster is also another example of how resistance was tamed for use. Overall, for large scale energy production and storage, resistance remains the enemy.

Normal superconductors, using extremely low temperatures or extremes of pressure, alter the physical dynamics of materials used to create a condition where the normal expected resistance in the material is reduced, in an ideal condition, to zero. This reduction in resistance allows for a number of physical conditions to be possible, such as the lossless storage of electricity for an indeterminate amount of time or the lossless propagation of electricity with zero heat generation. Currently almost all energy storage is done through physical or chemical means. Low-temperature superconductors are typically defined as materials with critical temperature (T_c) values lower than approximately 20° K, (-423° F) which is the storage temperature of liquid hydrogen.

GENERATING ELECTRICITY IS EASY, STORING IT IS THE HARD PART

One of the goals of room-temperature superconductivity is the effective zero-loss propagation of electricity. Currently, energy is transmitted by power plants over large transmission lines, through transformers which step up the voltage for transmission, cramming as much energy into the lines as possible so that when it is transmitted there is less loss across the great distances between where power is generated and where power is consumed.

Once the energy is transmitted, a local transformer converts it back onto a form which can be used by households, and then a third time with a household step down transformer. Each of these transformations of electricity generates heat and loses electrical energy during transmission.

Room-temperature superconductors would reduce the loss of energy as the electricity is being transferred from power plants to homes, ensuring any energy generated is used, not lost, reducing fossil fuels being used to create electricity no one gets to use.

This become critical when we talk about the generation of electricity through renewable means which will have a key role in providing energy in the future while reducing greenhouse gas emissions and fossil fuel use. One of the key issues in renewable energy is integrating such power into our existing power grid. Renewable energy happens independent of demand and is unlike current fossil fuel power, unable to be dialed up upon a need for increasing demand, such as during summer heatwaves.

Power storage for renewable energy, a means by which we can store, hold and release such energy, as needed, is one of the major goals of room-temperature superconductivity. Currently we can store large amounts of energy but those technologies don’t tend to be fast-reacting. There are other forms of energy storage which can react quickly but don’t store much energy. This is currently where the science of Superconducting Magnetic Energy Storage (SMES) is being developed.

SMES stores energy in the form of direct current electricity, passing the current through the superconductor and storing the energy as a direct current magnetic field. SMES was firstly introduced in the 1970s. An SMES device is an electrical device that can store energy in the form of a magnetic field induced by dc current flowing through the magnetic coils. Given that energy is stored in the form of current, energy can be drawn nearly instantaneously to give an extra advantage for SMES in terms of rapid time response. Because the superconductor is operating at cryogenic temperatures, there is no resistive loss as it produces the magnetic field. This means SMES systems are highly effective offering greater than 98% lossless energy storage. This lossless energy, unfortunately requires energy and technology to keep the superconductive material at subzero temperatures, which means the science of lossless energy storage exists, but it ironically, costs energy to create and maintain.

This is what room temperature superconductors hope to circumvent: avoiding the use of energy to store energy.

Our current methods of energy storage are always evolving and in the current development of room temperature superconducting materials, we are still expanding the capacity to store energy in physical systems and in the continued expansion of energy storage in battery technologies.

Physical energy storage is the lifting of heavy weights and then slowly allowing them to fall, generating electricity. Physical energy storage is constantly expanding and includes hydroelectric and flywheel technologies as well as the consideration of gravity-based generation as one of the newer forms of energy storage management, repurposing old mines and other areas of with new dynamic systems designed to temporarily store and release energy. However, such systems are vulnerable to wear and tear and are still largely unimplemented or experimental.

THE FUTURE OF ROOM-TEMPERATURE SUPERCONDUCTIVITY

The future of ambient temperature superconductors could revolutionize a number of technologies in development including:

• Magnetic levitation (maglev) transportation which could offer faster transportation with reduced energy costs.
• Medical use of superconductors currently support magnetic resonance imagining, and if room temperature superconductors were able to be used, they would increase the resolution and efficacy of magnetic imaging technologies while reducing the need to cool the devices with sub-zero cryogenic systems.
• Room -temperature superconductivity stands to revolutionize computing electronics which have almost reached the limits of current material science, offering increased power-efficiency and potentially further increasing their speed and efficacy.
• Space exploration, a field of scientific endeavor where weight and efficiency are peak considerations would benefit from such technology providing lightweight and highly efficient power systems for spacecraft and space stations.
• Industry and Manufacturing: Many industrial processes rely on electricity, and using superconductors could make these processes more energy-efficient and cost-effective.

A FINAL THOUGHT:

I only gave this thought when I was done with the piece because many superconducting materials are comprised of unusual rare earths or technologically-derived materials whose creation may be problematic at scale and might be difficult to achieve in bulk. A number of scientists also voice similar concerns indicating the creation of the material and the processes necessary might not allow the superconductive aspects to be applied in the manner we may have outlined in this piece.

A worst case scenario might be the ability to create materials capable of room-temperature superconductivity, but not be able to be able to produced such a material in bulk, rendering the technological aspects of the ambient temperature superconductor as a highly specialized resource due to the cost of production. The development of ambient temperature and pressure superconductors may be just the first step in a long chain of development, refining existing technologies and requiring further development directed toward creating less-expensive variants or limited versions of the technology with some aspects of the material, but with a greater capacity for mass production in the future.

¹ The First Room-Temperature Ambient-Pressure Superconductor
https://arxiv.org/abs/2307.12008