NRNU MEPhI: Energy Storage on Superconductors

Main article: Energy storage systems (NOS)

2023: Superconductor Energy Storage Development Announcement

Scientists National Research Nuclear University MEPhI development of accumulators energy of updated type, based on properties of modern high-temperature ones. superconducting materials The development is supported by the Priority 2030 program. This was announced on February 27, 2023 by representatives of MEPhI.

Energy storage on superconductors

As reported, first of all, work is underway on the design of the so-called kinetic energy storage. It will be a bearing made of modern superconducting composite materials, floating in the gradient magnetic field created by permanent magnets due to the magnetic levitation effect. Thus, this bearing will not touch the stationary parts of the device, but ideally it should float in a vacuum. Under these conditions, rotation of the bearing takes place almost without friction. If such a bearing is unwound (for example, using an electric motor that transmits rotation to the shaft through the connected magnetic clutch), then it will rotate in the void for months, saving the energy transmitted to it almost without loss. If necessary, this energy can be "removed" from it, for example, by again connecting a magnetic coupling and a generator to the bearing. It is planned that during 2023 a working prototype of the kinetic storage will be created.

The second type of drive is induction, and, in the opinion of an amateur, it seems even more incredible. If the winding made of superconducting material is energized with electric current, and then closed to itself, then a non-short circuit will occur (as it would be in a conventional electrical circuit), but the electric current will begin to flow in a closed circuit in a circle - and it, too, almost without loss, will maintain the amount of current, and therefore the stored energy, for weeks, and maybe months (depending on the degree of optimization of internal losses). Energy from such a storage can be partially or completely "removed" if necessary and transferred to the payload. In 2023, NRNU MEPhI plans to fundamentally develop a design for an induction drive "on paper" and calculate its technical characteristics.

The main possibility of storage devices of this type lies in their capacity: in terms of energy density to mass, storage devices on superconductors should be several times higher than conventional batteries. Also important is the ability to partially remove energy and recharge them during operation.

However, their important technical feature is that the composites used in the designs exhibit their superconducting properties only at very low temperatures. Although superconductors intended for use in the development of NRNU MEPhI are called "high-temperature," these temperatures can only be called high by the standards of the world superconductors. These drives can only work if the temperature inside them is maintained no higher than 77 degrees on the Kelvin scale - that is, a little more than minus two hundred degrees Celsius. This corresponds to the boiling point of liquid nitrogen and it is with it that they are going to maintain a low temperature inside the accumulator. As Igor Rudnev, professor at the LaPlaza Institute and leading researcher at the Superconducting Energy Systems laboratory, explained, liquid nitrogen is cheap enough, and modern thermal insulation systems will allow adding nitrogen to storage devices no more than once a month.

Of course, the question of the economy of such drives remains acute. Composite high-temperature superconductors and magnets made of rare-earth metals used in them are quite expensive. According to Igor Rudnev, these drives can be used in the "green "power and industry. For example, they can be used to increase the uniformity of energy generation at solar and wind power plants: when the wind or sun is there, the storage will be recharged, when natural factors fail - the storage begins to supply energy to the network. Also, they can be used as backup power supplies in industrial enterprises where great importance is has a continuous production. The use of such drives on large electric vehicles (like electric buses) is not excluded.

In the long term, NRNU MEPhI plans to create prototypes not only of storage devices, but devices of all phases of generation, production, transmission and storage of electricity using superconductors: add both a generator (wind or solar) on superconductors and a superconducting cable to the storage device. Thus, it will be possible to see a prototype of the electric power industry of the future, which will be the Superconductor Energy Cluster NRNU MEPhI.

The development of energy storage devices on superconductors was supported by the Priority 2030 program within the framework of the New Methods of Energy Storage and Transportation: Superconductor Energy Cluster subproject of the Strategic Project "New Generation Nuclear Energy Technologies and Extreme States of Matter."