• A bill banning new oil and gas heating systems starting next year is moving forward in Germany. The aim is to cut Germany’s greenhouse gas emissions and meet net-zero energy targets. If the Bundestag approves the bill in June, any heating system installed in new or old buildings after Jan. 1, 2024, must be 65 percent based on renewable energy. Exemptions will be made for people on low incomes, and subsidies will be available to help people make the transition, with the government covering 30 percent of the cost of installing new systems. Critics have called the plan unworkable and discriminatory.

• “Room temperature” ionic liquids have shown potential for a wide range of applications, including thermal energy storage. Theoretically, millions of different ionic liquids, each with different properties, can be synthesized in a lab. But that process is time-consuming and expensive. Now researchers at the American University of Sharjah, United Arab Emirates, say they have developed new data-driven predictive models to help narrow the selection and guide the testing and design of new classes of ionic liquids for use in energy storage systems.

kraftboxx heatstixx• In a LinkedIn post, Rubitherm Technologies GmbH of Berlin has announced a partnership with kraftBoxx of Aulendorf, Germany: “We are super excited to announce our cooperation with #KraftBoxx ‘water-guided PCM storage for cooling and heating’. It contains PCM encapsulated in #heatSels or #heatStixx; plastic ellipsoids designed with a large surface area, and small PCM layer thicknesses. So that, the entire PCM participates in the phase change process and thus efficient heat transfer is achieved even at very low temperature differences. Now, you can choose your desired operating temperature from our organic and inorganic PCMs for applications in refrigeration, air conditioning and heating.”

• A University of Bradford professor says thermal energy trapped in sewer systems could be used to heat homes. Mostafa Mohamed is conducting research into technology that would dramatically improve the efficiency of heat pumps used in this way. His focus includes the use of phase change materials. “We can recover heat from the soil, from tunnels and even sewers,” he said. “But the technology needs to become more efficient and competitive to increase its adoption.”

Cristina Prieto, an associate professor at the University of Seville’s School of Engineering, has been developing a new thermal energy storage concept based on four different phase change materials cascaded in series. Prieto is now coordinating the European Union’s four-year HYBRIDplus project involving three universities and four businesses, which began work at the end of 2022 to demonstrate her concept. The project will leverage the melting points of PCMs, ranging from 300°C to 600°C, held in four separate modules arranged in series inside a tank. “This is a new concept that has not been tested before,” Prieto said. “Instead of storing the heat in the conventional two molten salt tanks, we use PCMs, which store the energy as latent heat with higher energy density than sensible heat systems.”

Said Al-Hallaj, visiting research professor at the University of Chicago, and David Oliver, head of materials at Sunamp Ltd., are among the panelists at Thermal Management Expo 2023 in Novi, Michigan, May 2-3. The “Changing the Game with Phase Change Materials” panel will discuss systems based on immersion cooling, heat pipes and multilayer PCMs; the balance between performance, safety and cost; the role of PCMs in preventing thermal runaway and propagation; and how development of new thermal materials can be accelerated. Expo registration is free.

Dailya prototype
• Three master’s students at Imperial College of London are developing underwear that uses phase change material to provide heat to alleviate menstrual cramps. Their prototype features small packs filled with sodium acetate trihydrate and metal activation disks. The packs can be activated, one or more at a time, to apply heat where it is needed. After each use, the underwear can be cleaned and the SAT reset by machine washing at 60˚C. Team Dailya is looking to speak with experts in disk-activated SAT, product development and B2C ventures. The team is also looking for women willing to do initial user testing. Contact Mona Daud at

• The University of Córdoba, Spain, has sanctioned Rafael Luque, one of the world’s most cited scientists, over his research work for institutions in Russia and Saudi Arabia. Luque has been suspended without pay for the next 13 years. According to the newspaper El Pais: “Luque, 44, is one of the most prolific scientists in Spain. He has published some 700 studies, mainly in the field of so-called green chemistry, which aims to synthesize products such as drugs and fuels while generating less waste. So far this year, Luque has published 58 studies at a rate of one every 37 hours.”

Sunamp Ltd. is one of 148 U.K. organizations to receive the 2023 King’s Award for Enterprise. The honor, previously known as the Queen’s Award, recognizes outstanding U.K. businesses. In related news, Sunamp has been shortlisted for the Unlock Net Zero Live AwardsSupply Chain Partner of the Year and Climate Champion of the Year awards. Winners will be announced at the Chartered Institute of Housing’s annual conference in June.

Phase Change Solutions, Greensboro, N.C., is partnering with the Eastern Academic Health Science Network in a trial of PCM-enhanced medical refrigerators. Apollo BioPCM Smart Panels developed by Phase Change Solutions are fitted into the refrigerators. The panels are designed to reduce energy costs and keep the temperature regulated for longer in case of a power outage. The health network is part of England’s National Health Service.

Richard Bonner, former vice president for R&D at Advanced Cooling Technologies, has joined Accelsius as chief technology officer. Texas-based Accelsius, formed in 2022, is developing cooling technologies and products for data centers.


• Through a recruiting firm, a North American thermal energy storage provider is seeking candidates for director of business development. The provider “owns and operates the largest fleet of utility thermal energy storage assets in the country. Their products help commercial and industrial customers save energy while giving utilities a dispatchable peak shaving asset.”


Wood template-supported phase change composite for thermal energy applications

U.S. patent application 20230111862 (applicant Alliance for Sustainable Energy LLC, Golden, Colorado, and Board of Regents, University of Texas System, Austin, Texas):

“The present disclosure relates to wood template-supported phase change material (PCM) composites having thermal energy storage applications. A wood template-supported PCM composite may include a wood template that has had at least a portion of its xylan and/or lignin removed and saturated with a PCM. The PCM may be stabilized with a cross linkable network for improved infiltration into the wood template. The wood template-supported PCM composite may be formed by extracting xylan and/or lignin from the wood to create a wood template, densifying at least a portion of the wood template, and inserting a PCM into the wood template.”

Gripper device

U.S. patent application 20230124447 (applicant Rolls-Royce plc, London):

Rolls-Royce patent drawing

“A particle gripper comprising a flexible surface membrane connected to a resiliently deformable neck portion which has a cavity filled with a phase change material, and at least one air tube, the flexible surface membrane and the phase change material are configured to deform around an object to be gripped; and wherein the at least one air tube is used for inflating and/or creating a vacuum within the cavity such that the cavity can be inflated so that the phase change material is forced against the flexible surface membrane to expand the flexible surface membrane, and a transition means which is applied to the phase change material in the cavity so that it changes phase of the material from a liquid to a solid so that object is gripped by the flexible surface membrane and the phase transition material.”

Thermal fuse

U.S. patent 11631565 (applicant Science Applications International Corp., Reston, Virginia):

“A thermal fuse may comprise an electrode and a conductor separated by a phase change material. The electrode may be formed from a conductive material that generates hydrogen when exposed to water or hydrogen peroxide. The phase change material may release water or hydrogen peroxide at or above an activation temperature.”

Buoyancy based platform assembly

Buoyancy platform patent drawing

U.S. patent application 20230119645 (applicant Georgia Tech Research Corp., Atlanta, Georgia):

“The disclosed technology includes systems and methods of managing temperature distributions of phase change material. The disclosed technology can include a system comprising a platform having a passageway therethrough. The platform can include a density that is less than a density of the phase change material when in a solid phase and greater than a density of the phase change material when in a liquid phase. The system can further include a whip rod disposed at least partially in the passageway of the platform.”

More U.S. patents and patent applications:

Compositions comprising phase change materials and methods of making the same (Phase Change Solutions Inc., Greensboro, N.C.) | Even carbon number paraffin composition (REG Synthetic Fuels LLC, Ames, Iowa) | Dry ice containing shippers (Robert R. Sever, et al, Northbrook, Illinois) | Thermal mass for heat pre-load and time-controlled dispersion in building heating systems (Trustees of Columbia University, New York, N.Y.) | Low-cost container condition monitor (IBM Corp., Armonk, N.Y.) | Coated sponges (Dow Global Technologies, Midland, Michigan) | Thermal storage device for batteries (Toro Co., Bloomington, Minnesota) | Pallet cover (Cold Chain Technologies LLC, Franklin, Massachusetts)


From Journal of Energy Storage:

Employing the double-PCM (Phase-Change Material) layer to improve the seasonal adaption of building walls: A comparative studies
Melting process of RT-25 as a phase change material by placing innovative rectangular and parallelogram fins: Effect of shape and angle of fins
Preparation and performance of lauric acid phase change material with the double-layer structure for solar energy storage
Phase change materials designed from Tetra Pak waste and paraffin wax as unique thermal energy storage systems
Experimental analysis of clay bricks incorporated with phase change material for enhanced thermal energy storage in buildings

From Case Studies in Construction Materials:

Mechanical, thermal and microscopic properties of gypsum matrix composites containing capric acid-palmitic acid/urea-formaldehyde microcapsules

From Meat Science:

Biodegradable form stable phase change material for cold storage packaging of meat

From The Journal of the Textile Institute:

Shape-stabilized composite phase change material for thermal insulation of cotton fabrics with sandwich structure

From Journal of Thermal Science:

Discharging of PCM in Various Shapes of Thermal Energy Storage Systems: A Review

From Thermo:

Preliminary Design of a Space Habitat Thermally Controlled Using Phase Change Materials

From Polymer Bulletin:

Influence of polyaniline conducting polymer on thermal properties of phase change material for thermal energy storage

From Journal of Thermal Analysis and Calorimetry:

Hexagonal boron nitride-loaded macroporous foams as frameworks for development of n-eicosane-based composite phase-change materials
Thermal conductivity of solid paraffins and several n-docosane compounds with graphite

From International Conference on Energy Conservation and Efficiency:

Determination of Thermal Properties of Eutectic Phase change materials (EPCM) using the T-history method

From Energy:

Coupling of flexible phase change materials and pipe for improving the stability of heating system

From Energies:

An Overview of the State of the Art and Challenges in the Use of Gelling and Thickening Agents to Create Stable Thermal Energy Storage Materials

From Polymer:

Encapsulating an inorganic phase change material within emulsion-templated polymers: Thermal energy storage and release

From Solar Energy Materials and Solar Cells:

Mechanical agitation triggered crystallization of eutectic phase change material xylitol/erythritol with persistent supercooling for controllable heat retrieval

From Cement and Concrete Composites:

Machine learning guided design of microencapsulated phase change materials incorporated concretes for enhanced freeze-thaw durability

From Journal of Building Engineering:

Performance evaluation of a pipe-embedded phase change material (PE-PCM) roof integrated with solar collector

From Numerical Heat Transfer:

Transient thermal performance enhancement of phase change material (RT82) through novel pin arrangements under varied gravity conditions

From European Polymer Journal:

Bead-free and beaded electrospun phase change fibers: A comparative study

From Case Studies in Thermal Engineering:

Comparative study for photovoltaic cooling using metal mesh inserted eutectic phase change material enclosure


Connect with PCM experts and industry leaders on LinkedIn

LinkedIn logoMore than 1,750 people have joined a LinkedIn group devoted to the discussion of phase change material and thermal energy storage. You are invited to join the Phase Change Matters group and connect with PCM and TES experts from around the world.

This month we welcome Cully Firmin, research and development contractor, Scott, Louisiana; Mark van der Klok, virtual modeling expert at Versuni, Assen, Netherlands; Pier Paolo Figiaconi, Ph.D. student at Polytechnic University of Milan, Milan, Italy; Rob Buskermolen, operations lead at Thermeleon, Delft, Netherlands; and Silvia Paredes Buendía, architect, Murcia, Spain.


Does your company, agency or university have a job opening, new research, new product or other news you’d like to share? I would love to hear from you. Please contact newsletter editor Ben Welter at


RAL Quality MarkThis newsletter is made possible through the generous support of the RAL Quality Association PCM and the members listed below. To learn more about the association, including membership benefits, please contact Stefan Thomann, executive director, at

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