Citation: Ferreira da Silva, F.; Fernandes, J.F.P.; da Costa Branco, P.J. Superconducting Electric Power Systems: R&D Advancements. Energies 2022, 15, 7350. https:// doi.org/10.3390/en15197350 Received: 22 August 2022 Accepted: 8 September 2022 Published: 6 October 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). energies Editorial Superconducting Electric Power Systems: R&D Advancements Francisco Ferreira da Silva , João F. P. Fernandes and Paulo José da Costa Branco * IDMEC—Instituto de Engenharia Mecânica, Técnico Lisboa, University of Lisbon, 1049 Lisbon, Portugal * Correspondence: pbranco@tecnico.ulisboa.pt 1. Introduction According to the report “Global Energy Perspective” by McKinsey and Co. in 2022, the energy transition will continue to gain momentum, with oil demand projected to peak possibly as soon as 2025. Compared to today’s demand, power consumption is estimated to triple by 2050 as both electrification for deep decarbonization and living standards grow. Electromobility is pointed to as a key important step toward the energy transition, especially with the electrification of automotive and, more recently, aircraft propulsion [1–3]. In time, all these movements will lead to the need for more power plants, accompanied by high- capacity cable systems, all associated with the demanded significant level of renewable resources, such as offshore wind generators [4] and solar power. With the power demand clustering near metropolitan areas, countries are becoming characterised by highly concentrated energy pockets. These pockets are made up of relatively short transmission/distribution lines organised in a mesh network to enhance the reliability and flexibility of power transmission. This makes it very difficult to install more overhead lines and underground tunnels for power transmission, and it is also not possible to build major large-sized facilities such as power plants and substations near cities. Additionally, there is an increasing short-circuit capacity in the existing power grid, causing greater fault currents that might exceed the interrupting rating of the existing power circuit breakers in many substations [5,6]. As approached in this Editorial, superconducting power technology can suppress these flaws. Being a technology with higher values of specific power and energy density than the conventional technology, it can facilitate the smallness of power equipment decisive in highly populated areas. Accompanied with this is the reduction in power loss in the main electric power equipment, offering higher efficiencies than conventional facilities [7,8]. Furthermore, superconducting technology is also revolutionising the future of electromobility as a key enabler for future electric aircraft due to their potential ability to allow higher specific power electrical machines. As one of its main drawbacks, superconducting power technology is not largely used mainly due to its cooling requirements that are associated to still unneglectable AC losses in high-superconducting tapes and cables. In a wider sense, AC is encountered in any transitory regime, and this aspect interests superconducting apparatus engineers the most. More efficient cooling technologies and superconductors that keep superconductivity up to higher temperature levels are being studied to mitigate the impact of these challenges. Despite its drawbacks, in recent years, many field tests of the superconducting appara- tus have been conducted, as recently shown in [2,5,8]. The results of the tests prove that the superconducting technology is useful, reliable, and not so difficult to handle in comparison with the conventional one. This editorial paper presents and discusses the R&D and tests of superconducting technologies that aim to demonstrate the performance of this technology in electric power systems for more efficient use of energy. The editorial covers: • AC losses [9]; • HTS Power Cables [10–12]; • Superconducting Fault Current Limiters (SFCL) [13–15]; • HTS Electrical Machines [16–20]. Energies 2022, 15, 7350. https://doi.org/10.3390/en15197350 https://www.mdpi.com/journal/energies