Proceedings of the International scientific and practical conference ―Science, technology and art in global context (July 8-10, 2025) / OP website: www.naukainfo.com. – Dresden, Germany, 2025. - 140 p.

117 POWER ENGINEERING AND POWER MACHINE ENGINEERING UDC 536.7:621.577:697.9 Ihor Pysarevskyi PhD Student Ihor Mukminov PhD, Senior Lecturer Ela Altman PhD in Technical Sciences, Associate Professor, Odesa National University of Technology Odesa, Ukraine Illia Pysarevskyi student, Taras Shevchenko National University of Kyiv Kyiv, Ukraine APPLICATION OF ANNULAR CHANNELS WITH POROUS MEDIA FOR THE UTILIZATION OF LOW-GRADE THERMAL ENERGY Abstract: This article presents a method for utilizing low-grade thermal energy (<180 °C) using annular channels filled with porous media, especially sand. This design integrates heat exchange and thermal storage, providing high efficiency due to large surface area and heat capacity. The impact of channel geometry and filler properties is analyzed. Sand is proposed as a low-cost, durable, and safe thermal storage medium. Application areas include ventilation systems, flue gas recovery, and industrial/domestic heat reuse. Efficiency levels up to 90% are achievable. The