Nick Boykov: So, your work lies in a variety of spheres with the main one being high temperature superconducting materials and thus, you were nominated for the Global Energy Prize this year for your exceptional achievements in creating wires using these materials in the sphere of Electric Power Industry. So, how do those spheres work, how do those wires work and what advantages do high temperature superconducting materials give them?
Amit Goyal: Right. So, I got into this field of high temperature superconductivity in 1987 and a Nobel Prize for the discovery of high temperature superconductors was given in 1987. It was a first in the history of science that a Nobel Prize was given one year after the discovery of these materials. So, the Nobel Prize, even in the announcement, it talked about the immense applications that these materials may have, right, and change the way we live.
However, for all of these largescale applications one needed many of them being in the electric power industry where energy is central. One needed these wires to be kilometers long, be flexible, and be able to carry large amounts of electricity. And it turns out that these high temperature superconductors are ceramic materials, they are like mud in a flowerbed. So you first of all have to make a flexible wire, which is kilometres long, but it had to carry millions of amps – amperes of current per unit cross-section. So, how do you do that? And so fundamental research that I was involved in for many years determined that the only way to do that is that we needed these wires to be single crystals. So, here is the problem.
If you ask the question: what is the largest crystal that man has grown? And the answer to that question is silicon, 18 inches in diameter and one and a half metres long. So challenge here was in the field was to grow, to make single-crystal-like, kilometres long wires, which are flexible, can carry, our single crystal can carry large amounts of current but can be made for the price of copper wire that you buy in the hardware store. And so, for the most part, initially around the world people had said well, this can’t be done. And so that’s really became the central piece of my work and we came up with several ways of doing this.
One way is called RABiTS. Let me just back up. So this became the first Holy Grail in the field of applied superconductivity, right, around the world. So we came up with the first process, the one that we came up with when I was at Oak Ridge National Laboratory called RABiTS. And it stands for Rolling Assisted Biaxially Textured Substrate. So what we do is we use thermal mechanical processing similar to methodology to make aluminium foil that we use in the kitchen, right. So we use a similar process called thermal mechanical processing to create a flexible metal template, which is single-crystal-like, in which all the atoms in all three directions are aligned with respect to one another. Then on top of this substrate we grow different layers. Their atomic structure is aligned with the atomic structure of the substrate below, and then we eventually deposit the superconductor hence we get is single-crystal-like superconductor, which is flexible and can be made in long lengths. And so there are companies around the world, which are making routinely kilometre-long wires using this process.
The second process was originally invented in Japan in a company called Fujikura, then worked on at Stanford and Los Alamos National Laboratory, and it’s called the Ion-Beam Assisted Deposition process. And we came up with what’s called the LMOE process, which is we came up with critical buffer layer that is put on top of the substrate to make this process economically feasible in long length. So in this process, in contrast to the previous one you gain harder metal, which is flexible, but in that metal no atoms are aligned in any direction, and then you deposit some layers, which are completely amorphous, meaning they don’t have any crystalline structure, and then you deposit one layer called the IBAD, in which all the atoms are aligned in all directions, and then you deposit some other layers, and then the superconductor, right. So today every company around the world is using either the RABiTS process or LMOe-based IBAD MgO process to make long lengths of superconducting wires. So that’s what the first Holy Grail of superconductivity was.
After we finished this work, for applications they wanted better performance, so we needed to improve the amount of current that the wires could carry in high applied magnetic fields. And so, really the structure that was needed is that within each wire at nanoscale we needed columns, which were non-superconducting. How do you do that? It’s not easy to do that. The only way one could do that was by bombarding with heavy ions in an accelerator, right. And that is too expensive, and it makes the metal radioactive. So we came up with the process called self-assembly, 3D self-assembly where we, during the growth of the superconductor layer, we automatically create these defects.
For today, the highest-performance wires around the world are fabricated using this process along with one of those two, right. So right now, every company around the world, which is making superconducting wire for all the applications that we can discuss later on, right, they use one of these three platform technologies to make the wire. So that’s really the critical piece of these wires, is the critical technology, which is very unique, you can’t make these wires in any other way.
Nick Boykov: That is very impressive, thank you very much. What would be the large-scale applications and in what way does your technology improve these spheres?
Amit Goyal: So there are a numerous set of applications, large-scale applications. So let me go in various ways like generation, transmission, etc. So let’s start with energy generation. So the first aspect of energy generation would be what is now becoming in the last two years very-very interesting and impressive is the possibility of finally having commercial nuclear fusion. And the only reason that possibility has come up is because of the existence of the wires that I just mentioned above.
Prior to those wires, superconductors that one had was a low temperature superconductor. You had to go way down in temperature to use them and the magnetic field they could generate in a magnet was much lower. Now with these wires you can go to very high fields and thus create very high magnetic fields to contain the plasma, nuclear plasma so that companies like Commonwealth Fusion Systems, which were recently incorporated, to realise commercial fusion.
There is another way that superconducting work, which has nothing to do with fusion, and that has to do with wind turbines. So offshore wind turbines, right. In offshore wind turbines, superconducting generators on the turbine allow for twice the power but can be <…> by the same mechanical mast that you have. So there is a great deal of interest in using superconducting generators in offshore wind turbines and American Superconductor is a leading company, which uses the RABiTS wire, is working on HTS generators.
Then let’s go to energy transmission, which is a very big area. So you can make superconducting cables and they allow for transmitting large amounts of energy in a loss-free manner. So, important point to note is more electricity is lost in the United States from transmitting power from one location to another that is used in the entire continent of Africa. That’s a lot of energy lost. So, superconducting cables allow you to carry large amounts of current to high population density areas. And there are right now around the world many HTS cable installations and we are just waiting for the trillion dollar electric power industry to make a little hole which says OK, we’re ready to revamp and go to the next level, right. And so that’s when all these applications are just going to come in a big way.
The next thing would be electric power industry to use of various things like high-efficiency motors, transformers, fault current limiters. The telecommunications industry was completely modernised by fiber-optic cable, right. Everybody has fantastic communication now. Well, the electric power industry is many times larger than the telecommunications industry. It uses motors, transformers, fault current, all kinds of things, which require energy efficiency. When you make superconducting motors, transformers, fault current limiters and niche applications, superconductors provide significantly higher energy efficiency. So all of those applications are being demonstrated worldwide, including in Russia.
Energy storage. So there are two kinds of energy storage that you can do with superconductors, right. One is called superconducting magnetic energy storage. Well, what happens here is that a magnetic field created by a floor of direct current and a superconducting coil, which is been cooled down to low temperatures below the superconducting temperature, the current will stay there and you can tap it when you need it. It can store large amounts of energy for the electric power grid, for example.
Second is a flywheel system. In fact, Boeing in America, as well as another company called Revterra in Texas, it’s like a bearing system. So they convert electrical energy into mechanical energy and a flywheel just rotates mechanically in a loss-free way and you can tap energy out of it when you need it. So one is storing energy in the form of a current, one is storing energy in the form of mechanical energy, both superconducting storing systems. Then you’ve got all accelerator magnets around the world for fusion, for whatever you want. Accelerator magnets around the world use half to half superconductors for the magnets and all the physics applications around the world in labs, laboratories, everywhere you use these wires.
The final application I would talk about is electric ships and planes. So there is a great deal of interest in the future because of the environment, right. People want to use electric planes and electric ships. So, 5-year NASA study finds superconducting machines could develop, could lead to the development of an all-electric plane with zero emissions. Airbus has just launched the Advanced Superconducting Cryogenic Experimental Powertrain Demonstrator called ASCEND. ASCEND is the acronym. By introducing the superconducting materials, they hope it can lower the electrical resistance so the current can supply power without any loss. And coupled with liquid hydrogen and cryogenic temperatures it becomes really quite interesting. In fact, in Russia a Yakovlev Yak-40 plane has been modified with a superconducting electric motor and propeller, and it just came out recently in 2021.
And then finally ship degaussing. Ship degaussing is a big application for high-temperature superconductors. Why? Because ship degaussing is a process to make steel, ship’s hull effectively non-magnetic by producing an opposing magnetic field. And so that is a big application that is been looked at for Navy, US Navy’s amphibious transport dock ships LPD 28 and 30. So you know, when these applications become big, they are certainly in billions of dollars around the world.
Nick Boykov: Sure, sure, thank you very much. And as you know, there is now a common trend in energy and manufacturing as well for eco-friendliness, which of course corresponds to the Sustainable Development Goals of the UN. So, if we take high temperature superconducting materials and all the technologies that are based on them, to what extent do they contribute to the SDGs and so they at all?
Amit Goyal: Superconductivity and superconducting materials is an ultimate energy saving technology and its practical implementation will contribute to significant reduction of CO2 emissions, improve water purification, reduce waste, and prepare for natural disasters.
So, the SDGs. There are 17 SDGs, as we all know. There are 5 of them, which directly relate to high temperature superconductors. The first is number 3 “Good health and wellbeing”, second is number 7, which is “Affordable and clean energy”, third is number 9 “Industry, innovation, and infrastructure”, electric power is a big infrastructure piece, 13 is “Climate action” because when you save energy losses, as I mentioned there can be significant losses in transmission for example. That’s the amount of, you know, CO2 you save, because you don’t have to produce, because you save that energy, right. And the last is “Clean water and sanitation”. So I’ve spoken about all of these applications except clean water and sanitation, but let me just touch upon that.
Access to fresh water is huge with only 2.5% of the water on Earth being fresh and climate change modelling forecast is saying that many areas are gonna become drier. The ability to recycle water in a compact water recycling systems from sewage and groundwater is critical. So, what do superconductors have to do with that? Well, magnetic separation systems based on superconductors is a huge application. High-gradient magnetic separation called HGMS is a core of a superconducting magnetic separation water treatment system. It is used to separate suspended solids from the medium using a magnetic force.
And this is being used in a number of areas right now. You can use by choice a suitable absorbent, you can recover heavy metals or pharmaceutical products from wastewater and all of this is possible, capacity of 2000 tons has been demonstrated today. So, all of these applications including the magnetic separations system will directly have an impact to the SDG goals. Now besides these five that I’ve mentioned, which directly are affected by superconductivity, some of the other SDGs are indirectly affected as well.
Nick Boykov: That is very-very interesting, that you very much. So as we now know, your technologies have a lot of potential applications, but if we take just simple ordinary people all over the world, how can superconductors, especially high temperature superconductors help them?
Amit Goyal: So, most of the applications for high temperature superconductors are not consumer applications only because these materials need to be cooled down, right, to a certain temperature like liquid nitrogen temperatures. And so, these are more large-scale applications, but in a developed area in a city all the applications that I mentioned, every single one of them in an urban area are of interest, from energy generation, from transmission, storage, use in the electric power industry, water separation, all of that, right. However, even in remote villages, right, which are not urban centres, you can think about distributed power. So wherever distributed power, like solar is there, you can connect that with, you know, in case in a remote village, you can put up a solar farm. Well, how do you get the power from there to the cities, for example, or vice versa, while you can have a DC superconducting line connecting them? You can think about clean water, you can have a water treatment plant in a remote area, which could continuously take the sewage and treat it. You can use an energy storage system in remote areas. So, I think in both urban areas and remote areas use of superconducting technology could help.