Ultra-high-temperature electrocaloric heat pump

Klinar, Katja (author), Gačnik, Darja (author), Kitanovski, Andrej (author)

Nearly a quarter of waste heat is generated at temperatures exceeding 300°C, yet conventional heat pump technologies remain inefficient in recovering and utilizing heat from such high temperature sources. In this study, we introduce a novel electrocaloric heat pump designed to operate with heat sources and sinks at ultra-high temperatures. The proposed heat pump system incorporates an active electrocaloric regenerator featuring PbZr$_{0.52}$Ti$_{0.48}$O$_{3}$ (PZT) epitaxial thin-film multilayers, which exhibit a superior electrocaloric adiabatic temperature change of 11.03 K at 402°C (675 K), and pressurized helium gas as the working fluid. We conducted a parametric analysis to simulate the performance of the ultra-high-temperature electrocaloric heat pump and identified the optimal conditions for single- and multi-stage configurations. The single-stage setup achieved a maximum heating COP of 7.8 at a 30 K temperature span across the regenerator at a heat source temperature of 660 K. In comparison, the multi-stage configuration yielded the highest heating power 113.3 W/kg$_{EC}$ and a max. COP 2.7 between 630 and 690 K. This study established a foundation for notable advancements in ultra-high-temperature heat pumps by employing electrocaloric energy conversion.

• Language: English
• Keywords: heat pumps, high-temperature, electrocaloric materials, caloric materials, energy conversion, heat transfer, regenerators, solid-state
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 11 str.
• Numbering: Vol. 349, art. 120814
• PID: 20.500.12556/RUL-177429
• UDC: 621.577:536.2
• ISSN on article: 0196-8904
• DOI: 10.1016/j.enconman.2025.120814
• COBISS.SI-ID: 262744067
• Publication date in RUL: 23.12.2025

Record is a part of a journal

• Title: Energy conversion and management
• Shortened title: Energy convers. manage.
• Publisher: Elsevier
• ISSN: 0196-8904
• COBISS.SI-ID: 2618919

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: toplotne črpalke, visoke temperature, elektrokalorika, pretvorba energije, prenos toplote, regeneratorji, stanje trdnosti

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P2-0223
• Name: Prenos toplote in snovi