Preface/Editorial: special issue on the 7th international seminar on ORC power systems

This editorial accompanies a Special Issue of Applied Thermal Engineering dedicated to the 7th International Seminar on ORC Power Systems (ORC2023) held in Seville, Spain between the 4th and 6th of September 2023. The Special Issue comprises ten research articles, selected by the organizing committee of ORC2023, that collectively explore the advancement of organic Rankine cycle (ORC), carbon dioxide-based power cycle, and reversible heat pump–ORC systems. The featured studies address challenges at different technology readiness levels and using diverse approaches—from conceptual and numerical, to experimental validation—and cover a broad range of applications, including energy storage, solar power and waste heat recovery and conversion from industry, data centres and marine engines. This editorial presents briefly the research reported in the ten selected articles.