ELECTROCALORICS - Laboratory for refrigeration and district energy

High-temperature electrocaloric heat pump presented at the High-temperature heat pump symposium

admin — Fri, 23 Jan 2026 09:56:23 +0000

Researchers from the Laboratory for Refrigeration and District Energy (LAHDE) have visited High-temperature heat pump symposium in Copenhagen, Danmark. The event offered an excellent overview of the latest research and industrial developments in high-temperature heat pumps, with many insightful discussions and opportunities to exchange perspectives with experts from industry and academia.

We were pleased to present our work on solid-state electrocaloric heat pump in the poster session and to receive valuable feedback that will support our ongoing research. Many thanks to the organizers for a well-structured and high-quality symposium, and to all colleagues for the engaging discussions.

The post High-temperature electrocaloric heat pump presented at the High-temperature heat pump symposium first appeared on Laboratory for refrigeration and district energy.

Ultra-high-temperature electrocaloric heat pump

admin — Mon, 05 Jan 2026 09:01:01 +0000

Researchers from the Laboratory for Refrigeration and District Energy (LAHDE) have published first study on high-temperature electrocaloric heat pump in Journal of Energy conversion and management, one of the world’s leading scientific journal in the field of energy.

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_0.52Ti_0.48O₃ (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.

Link: https://www.sciencedirect.com/science/article/pii/S019689042501338X

The post Ultra-high-temperature electrocaloric heat pump first appeared on Laboratory for refrigeration and district energy.

Emerging opportunities for high-temperature solid-state and gas-cycle heat pumps

admin — Sun, 21 Dec 2025 12:51:38 +0000

Researchers from the Laboratory for Refrigeration and District Energy (LAHDE), together with an international team, have published a study in Nature Energy (Springer Nature), the world’s leading scientific journal in the field of energy. The paper offers the first comprehensive assessment of an often-overlooked opportunity: alternative high-temperature heat-pump technologies that could replace inefficient fossil-fuel combustion and direct electric heating in industry and the energy sector. Doing so could significantly reduce energy use, greenhouse-gas emissions, and thermal pollution.

Heat lies at the core of the energy challenge. Around 50% of final energy consumption is used for heating and cooling, and roughly 50% of final energy is ultimately released as waste heat—heat that is frequently discharged into the environment via cooling towers, the warming of rivers or seawater, and other outlets. The study shows that high-temperature heat pumps can capture this waste heat and upgrade it efficiently to much higher temperature levels, suitable for demanding industrial processes.

Today’s commercial high-temperature heat pumps are typically limited to about 250 °C, whereas many industrial processes require higher temperatures—up to, or even beyond, 1000 °C. The newly published research therefore systematically presents and compares alternative approaches that could enable a step change: caloric, thermoelectric and thermoacoustic technologies, as well as mechanical processes based on Stirling and Brayton cycles.

Link: https://www.nature.com/articles/s41560-025-01908-4

The post Emerging opportunities for high-temperature solid-state and gas-cycle heat pumps first appeared on Laboratory for refrigeration and district energy.

Visit of Prof. Xiaoshi Qian to LAHDE

admin — Mon, 28 Jul 2025 07:58:33 +0000

We were honored to host Prof. Xiaoshi Qian from Shanghai Jiao Tong University during his recent visit to Slovenia.

Prof. Qian delivered a compelling lecture titled “Harnessing Giant Electrocaloric Effect in High-Polar Entropy Materials”, offering fresh insights into the development of high-performance electrocaloric polymers. His talk sparked engaging scientific discussions with members of the LAHDE team, as well as with guests from the Faculty of Mechanical Engineering, University of Ljubljana, and the Electronic Ceramics Department (K5) at the “Jožef Stefan” Institute.

As part of the visit, we had the opportunity to showcase our laboratory facilities and share some of LAHDE’s current research efforts, from recent patents and experimental work to our broader research activities. Our colleagues from the Jožef Stefan Institute also presented their advanced material characterization capabilities, which further enriched the exchange. The visit highlighted several shared research interests and laid the groundwork for future collaboration in the field of caloric and solid-state cooling and heating technologies.

We sincerely thank Prof. Qian for his visit, the insightful discussions, and the opportunity to strengthen international scientific ties. We look forward to continued collaboration and knowledge exchange.

The post Visit of Prof. Xiaoshi Qian to LAHDE first appeared on Laboratory for refrigeration and district energy.

World Refrigeration Day

admin — Thu, 26 Jun 2025 06:19:08 +0000

World Refrigeration Day, celebrated on June 26, was established to raise awareness about the critical role refrigeration, air conditioning, and heat pumps play in modern life. It honors the birth of Lord Kelvin (William Thomson), a key figure in thermodynamics. The day highlights the industry’s contributions to health, food safety, energy efficiency, and environmental protection. Institutions and organizations around the world celebrate it with educational campaigns, public events, webinars, and technical seminars, aiming to inspire innovation and promote sustainable practices in cooling technologies.

TCCbuilder: an open-source tool for the analysis of thermal switches, thermal diodes, thermal regulators, and thermal control circuits

admin — Mon, 11 Nov 2024 07:21:40 +0000

Researchers of the LAHDE laboratory of the Faculty of Mechanical Engineering, University of Ljubljana, have developed an open-source tool for 1D modeling of thermal control circuits, TCCbuilder. It is the first tool of its kind that enables quick and easy modeling of thermal control circuits thanks to its graphical user interface and thr associated library of materials used to create thermal control elements.

In addition to the library of materials, there is also a library of already designed thermal control elements from the literature. Researchers from various fields are invited to complement both libraries as well as to add functionality to the tool. Thus, TCCbuilder is not only an indispensable tool for simulations, but also a platform for the exchange of information and networking of researchers in the field of heat transfer and materials.

The tool is presented in the article TCCbuilder: an open-source tool for the analysis of thermal switches, thermal diodes, thermal regulators, and thermal control circuits, which describes the validation and examples of the use of the tool. The article is published in the journal iScience (IF = 4.6), Special Issue: Advanced thermal control: fundamentals and applications.

The article is freely accessible under the following link: https://doi.org/10.1016/j.isci.2024.111263

Summary:

In the area of thermal management, thermal control elements (TCEs) and thermal control circuits (TCCs) are proving to be innovative solutions to the challenges of temperature control and heat dissipation in various applications, ranging from electronic cooling to energy conversion and temperature control in buildings. Their integration promises to improve power density, energy efficiency, system reliability and system life expectancy. With the aim of connecting researchers in the field of thermal management and accelerating the development of TCEs and TCCs, we have developed an open-source TCC simulation tool called TCCbuilder that enables a quick and easy time-dependent 1D numerical analysis of the behavior of TCEs and TCCs. It uses the heat conduction equation to solve temperature profiles in different devices. The TCCbuilder application offers features not previously available with any other TCC modelling tool: a large adjacent library of materials and TCEs as well as a user-friendly graphical user interface (GUI).

The post TCCbuilder: an open-source tool for the analysis of thermal switches, thermal diodes, thermal regulators, and thermal control circuits first appeared on Laboratory for refrigeration and district energy.

Calorics 2024, Cambridge

admin — Wed, 25 Sep 2024 10:25:17 +0000

The Calorics 2024 conference took place in the historic city of Cambridge (UK), at the Møller Institute in Churchill College. This event brought together leading experts, researchers, and industry professionals to exchange ideas and insights on the latest advancements in caloric materials and heat-pump technologies.

The presentations highlighted the recent development in magnetocaloric, electrocaloric, elastocaloric, and barocaloric materials, as well as their potential integration in (multi)caloric devices such as heat pumps and active regenerators.

The LAHDE’s contribution to the conference was Prof. Andrej Kitanovski’s presentation: »Challenges, opportunities, and future roadmap for energy applications of magnetocaloric materials«.

One of the standout moments of the conference was the demonstration of a refrigerator utilizing the barocaloric effect to efficiently pump heat, presented by Xavier Moya. Its cooling power was impressive enough to chill beers to the perfect temperature, which were then served to attendees after the presentations. We cannot wait for the day when we can have solid-state refrigerators in our own homes.

Attending the Calorics 2024 conference was an exceptional experience, offering invaluable opportunities for learning and collaboration, encompassed by the engaging discussions with fellow attendees. The wide range of presentation topics provided deep insights into the latest caloric materials and technologies.

We are excited to attend and present our research at the upcoming Calorics conference. We can’t wait to see how the field will develop in the future.

The post Calorics 2024, Cambridge first appeared on Laboratory for refrigeration and district energy.

SDEWES 2024

admin — Mon, 16 Sep 2024 05:20:19 +0000

The SDEWES 2024 conference in Rome was a truly remarkable event, bringing together leaders, researchers, and professionals dedicated to advancing sustainable development and energy systems. As one of the premier conferences in this field, SDEWES provided a unique platform for exchanging cutting-edge ideas and fostering collaborations that can drive global change.

Throughout the conference, a wide range of topics were covered, from renewable energy integration and smart grids to circular economy principles and sustainable urban planning. The diversity of perspectives and the depth of the discussions were nothing short of inspiring. It was clear that the collective expertise and passion of the attendees are key to addressing the complex challenges we face in creating a more sustainable future.

The LAHDE’s contribution to the conference was a presentation by Katja Klinar, who shared insights on “Heat Pump Modelling in District Heating and Cooling Grid.” This work is a crucial part of the SenergyNets project, which is paving the way for more efficient and sustainable energy systems.

Attending SDEWES 2024 was a powerful reminder of the importance of collaboration across disciplines and borders. The ideas and connections forged here will undoubtedly have a lasting impact on the future of sustainable energy and development.

Looking forward to continuing the journey with this incredible community and applying the insights gained from this experience.

The post SDEWES 2024 first appeared on Laboratory for refrigeration and district energy.

TCCbuilder WS: we discovered the possibilities of modeling thermal circuits

admin — Mon, 16 Sep 2024 04:28:31 +0000

On Thursday, September 5, we held an online workshop where we learned about the functionality of the open source tool for modeling thermal control elements and thermal circuits, TCCbuilder.

We discovered the possibilities of modeling thermal control circuits in various fields of application, which stimulated the discussion of the workshop participants – researchers from different parts of the world – in the direction of further development of the tool.

We would like to thank all the participants for their participation in the workshop and invite them to further collaborate on the project.

The post TCCbuilder WS: we discovered the possibilities of modeling thermal circuits first appeared on Laboratory for refrigeration and district energy.

Successful completion of ICR2023

lahde — Wed, 30 Aug 2023 13:29:43 +0000

We are pleased to announce that the LAHDE team has successfully completed its active participation in the 26th International Congress on Refrigeration (ICR 2023) in stunning Paris! This unique and extremely important meeting takes place every 4 years, and perhaps this year was all the more special because it returned to its birthplace. The Congress was founded in Paris in 1908 and was last held there 40 years ago.

Our team had the opportunity to participate in a variety of lectures and workshops (you can read about which lectures we gave here) that showcased the latest innovations in refrigeration technology. Attending the congress was an invaluable experience that allowed our experts to deepen their knowledge and network with fellow researchers from around the world.

The congress provided insight into the latest technologies, sustainable approaches and future challenges to be faced in the field of refrigeration. Discussions covered all aspects, from energy efficiency to environmental sustainability. We also had the opportunity to network with colleagues and partners from the industry and share valuable experiences that will certainly contribute to the further progress of our group.

We are already looking forward to the next 27th edition of the Congress in Seoul in 2027, and we are confident that we will actively participate and contribute to the discussions and innovations in refrigeration. Our commitment to progress and sustainable development remains unwavering.

The post Successful completion of ICR2023 first appeared on Laboratory for refrigeration and district energy.