Phase Change Matters RSS


The award-winning Phase Change Matters blog tracks the latest news and research on phase change materials and thermal energy storage. E-mail tips and comments to Ben Welter, communications director at Entropy Solutions. Follow the blog on Twitter at @PureTemp. Subscribe to the weekly PCM newsletter. Or join the discussion on LinkedIn.

Two Entropy advisors, Dr. Mohammed Farid and Lucas B. Hyman, are pleased to take your questions about PCMs and thermal energy storage. Send your questions to We'll select the best and post the answers here each week.




Research roundup: Rubber sealing materials; pork fat as novel PCM; thermal inertia of buildings; more

Ben Welter - Wednesday, September 20, 2017

Feasibility of Using Microencapsulated Phase Change Materials as Filler for Improving Low Temperature Performance of Rubber Sealing Materials [Soft Matter]

Evaluation of the nanofluid and nano-PCM based photovoltaic thermal (PVT) system: An experimental study [Energy Conversion and Management]

Investigation of pork fat as potential novel phase change material for passive cooling applications in photovoltaics [Journal of Cleaner Production]

Superwetting polypropylene aerogel supported form-stable phase change materials with extremely high organics loading and enhanced thermal conductivity [Solar Energy Materials and Solar Cells]

Polyethylene glycol-enwrapped silicon carbide nanowires network/expanded vermiculite composite phase change materials: Form-stabilization, thermal energy storage behavior and thermal conductivity enhancement [Solar Energy Materials and Solar Cells]

Solar desalination using solar still enhanced by external solar collector and PCM [Applied Thermal Engineering]

Using Thermal Inertia of Buildings with Phase Change Material for Demand Response [Energy Procedia]

Preparation of microencapsulated phase change materials (MEPCM) for thermal energy storage [Energy Procedia]

Study of thermal conductive enhancement mechanism and selection criteria of carbon-additive for composite phase change materials [International Journal of Heat and Mass Transfer]

PCM briefing: Three molten salt projects projects move forward in U.S., Germany

Ben Welter - Tuesday, September 19, 2017

Terrafore salt encapsulation• The U.S. Department of Energy has released funding to the Argonne National Laboratory for a scaled-up round of independent testing of Terrafore Technologiesencapsulated thermal energy storage in phase change salts. The materials, shown at right, are designed to operate in temperatures to greater than 800° C in a single tank that acts as both storage and heat exchanger.

• The Department of Energy has invited Terrestrial Energy USA to submit the second part of its application for a federal loan guarantee to support the licensing and construction of its Integrated Molten Salt Reactor

DLR has fired up the TESIS thermal storage facility in Cologne, Germany. One hundred tons of molten salt is alternately heated and cooled from 250 to 560 degrees Celsius in the test facility, which is designed to allow industrial-scale testing of temporary storage methods for renewable energy and waste heat. 

• Va-Q-tec AG is reporting a strong increase in its service business in the first half of 2017, up 54 percent to 8.8 million euros. The company, based in Würzburg, Germany, develops, manufactures and sells vacuum insulation panels and phase change materials. 

• New from Zion Market Research: "Global thermal storage market is expected to reach USD 5.7 billion in 2022, growing at a CAGR of 10.7% between 2017 and 2022"

Advanced combat clothing featuring "four-way stretch phase-change material" was on display last week at the annual Defense and Security Equipment International show in London. Royal College of Art researchers and designers collaborated with the Ministry of Defense on the prototypes, which are designed to be easy to run in and comfortable to wear.  

German researchers roll out PCM warming mats for greenhouse plants

Ben Welter - Tuesday, September 19, 2017

Researchers at the University of Zwickau's Institute for Textile and Leather Technologies are developing a latent heat storage mat that uses phase change material to increase plant root temperatures in cold seasons. 

Dr. Silke HessburgThe passive system, designed for use in greenhouses, requires no additional energy supply. Dr. Silke Hessberg, who is directing the research, says root climate control promotes plant growth efficiently.

"There are already various heating systems on the market, such as underfloor heating systems, hot water systems or electric and gas heaters," she says. "These are always cost-intensive heating systems, since energy must be actively supplied."

The Thuringian Institute of Textile and Plastics Research (TITK) is supporting the two-year project. TITK's Martin Geissenhöner identifies the PCM as paraffin. 

"We have different melting points. For the root project we use melting points between 5 and 42° C, specially 17° C," he says. "The PCM is encapsulated in a network polymer. It's like a sponge structure."

Research associate Nancy Schrader says the mats are placed on the soil surface. Work on the project began in May 2015 and is expected to conclude in December. 

Research roundup: PCM wallboard; composite Trombe solar wall; indoor thermal comfort; more

Ben Welter - Friday, September 15, 2017

Energetic performance of two different PCM wallboards and their regeneration behavior in office rooms [Energy Procedia]

Correlation between energy efficiency in buildings and comfort of the users [Energy Procedia]

Numerical study of a composite Trombe solar wall integrating microencapsulated PCM [Energy Procedia]

Design of High Temperature Thermal Energy Storage for High Power Levels [Sustainable Cities and Society]

Numerical analysis of heat transfer processes in a low-cost, high-performance ice storage device for residential applications [Applied Thermal Engineering]

Solid-liquid phase change investigation through a double pipe heat exchanger dealing with time-dependent boundary conditions [Applied Thermal Engineering]

Evaluation of energy efficient hybrid hollow plaster panel using phase change material/xGnP composites [Applied Energy]

Indoor thermal comfort assessment using different constructive solutions incorporating PCM [Applied Energy]

The experimental phase diagram study of the binary polyols system erythritol-xylitol [Solar Energy Materials and Solar Cells]

Multifunctional poly (melamine-urea-formaldehyde)/graphene microcapsules with low infrared emissivity and high thermal conductivity [Materials Science and Engineering: B]

Research roundup: Supercooling in paraffin slurry; double-composition microencapsulation; encapsulated nitrates; more

Ben Welter - Thursday, September 07, 2017

Reduction of supercooling in paraffin phase change slurry by polyvinyl alcohol [International Journal of Refrigeration]

Preparation, characterization, and thermal stability of double-composition shell microencapsulated phase change material by interfacial polymerization [Colloid and Polymer Science]

Heat transfer characteristics of a hybrid thermal energy storage tank with Phase Change Materials (PCMs) during indirect charging using isothermal coil heat exchanger [Solar Energy]

Hybrid network structure of boron nitride and graphene oxide in shape-stabilized composite phase change materials with enhanced thermal conductivity and light-to-electric energy conversion capability [Solar Energy Materials and Solar Cells]

Encapsulated Nitrates Phase Change Material Selection for Use as Thermal Storage and Heat Transfer Materials at High Temperature in Concentrated Solar Power Plants [Energies 2017]

Smart pet feeder keeps Fido's kibble cool with PCM

Ben Welter - Thursday, September 07, 2017

It's not much to look at, but an ingenious assembly of off-the-shelf electronic components could be just what a busy (and geeky) pet owner needs. The Mario Feeder allows users to schedule and monitor pet feedings from a smart phone and plays a personalized message alerting Fido when it's time to chow down. If Fido fails to heed the call, an alert will be sent to the owner's phone. Other features of the rotating dispenser include:

Mario FeederProximity detection: The bowl will open only when your RFID-tagged pet is nearby, to stop other animals from stealing food.

Bark detection: The feeder is "constantly listening" and will send an alert if your pet sounds distressed.

Smart scale: Tracks what your pet eats, when it eats and how much it eats.

Phase change material: Keeps perishable food cold. 

Developers have launched an Indiegogo campaign in hopes of raising $46,500 to help bring the product to market. They've also produced a video that might be the cutest ad you'll see on the Internet today:

Mario pet feeder video grab

Lead engineer Justin O'Neill answered a few PCM-focused questions by e-mail:

Q: What type of PCM is used? 

A: "We believe that the ability to keep food cold throughout the day is an important feature in a premium pet feeder, and strangely absent in competing products. We are using an organic PCM with a melting point of around 6 degrees Celsius. ... [It is] a bio-based PCM. This isn't because we believe there is a risk of food contamination (very small risk since we are using a robust casing) but more of a product life-cycle consideration with disposal."

Q: How is the PCM encapsulated? 

A: "The PCM is encapsulated in the walls and base of the main bowl, and it is recharged by placing the whole bowl into the freezer/ fridge. We did play with the idea of having separate removable compartments, but this did not fit with our ethos of reducing the total number of components. The bowl is sized so that it will fit in to most domestic freezers/ fridges (also less fiddly for the user). ... Our final design has two compartments with thicker base to hold more PCM. Prototypes have been developed with an ABS housing, but the final version could be PP or HDPE. ... We would have loved to use aluminium or stainless casing but the bowl is a fairly complex moulding and I suspect we would have ended up with high pressure die casting and a step change in cost."

Q: What are the dimensions of the product? 

A: "The bowl is ~310mm in diameter, depending on where exactly you are measuring. We tried to balance catering to larger pets with ensuring it isn't too big for apartments, and of course getting the food bowl with PCM it into a fridge/ freezer."

Q: How long does the product provide a cooling effect?

A: "Our intent is only to provide the ability to delay food spoiling, not keep it frozen or cold indefinitely. Our target has been delaying spoiling for 3-4 hours vs food being exposed, and obviously the performance varies greatly with ambient temperature, the foodstuff and volume of food. The Mario feeder allows users to set an expiration time. I.e after a specified time a particular compartment will be forbidden to expose even if the dog is near (RFID proximity detection) as food may be spoiled. By keeping food out of the sun (using proximity detection and rotating the bowl) we further improve total performance."

Research roundup: Influence of nanoparticle morphology; battery thermal management; concrete pavement; more

Ben Welter - Wednesday, September 06, 2017

Influence of nanoparticle morphology and its dispersion ability regarding thermal properties of water used as Phase Change Material [Applied Thermal Engineering]

The optimal allocation of the PCM within a composite wall for surface temperature and heat flux reduction: an experimental approach [Applied Thermal Engineering]

An innovative practical battery thermal management system based on phase change materials: Numerical and experimental investigations [Applied Thermal Engineering]

Using phase change material in under floor heating [Energy Procedia]

Incorporating phase change materials in concrete pavement to melt snow and ice [Cement and Concrete Composites]

Dynamics of phase change in a vertical PCM capsule in the presence of radiation at high temperatures [Applied Energy]

Experimental study on thermal performance of phase change material passive and active combined using for building application in winter [Applied Energy]

Thermodynamics behavior of phase change latent heat materials in micro-/nanoconfined spaces for thermal storage and applications [Renewable and Sustainable Energy Reviews]

Advancement in phase change materials for thermal energy storage applications [Solar Energy Materials and Solar Cells]

Study on solidification process of sodium acetate trihydrate for seasonal solar thermal energy storage [Solar Energy Materials and Solar Cells]

Research roundup: Carbonized rice; erythritol-xylitol; integrated double skin façade; paraffin-based TES system; more

Ben Welter - Wednesday, August 30, 2017

Form stable composite phase change materials from palmitic-lauric acid eutectic mixture and carbonized abandoned rice: preparation, characterization, and thermal conductivity enhancement [Energy and Buildings]

Mitigation against Crude Oil Wax Solidification using TES Fin [Chemical Engineering Research and Design]

Heat transfer analysis of an integrated double skin façade and phase change material blind system [Building and Environment]

Experimental Phase Diagram Study of the Binary Polyols System Erythritol-Xylitol [Solar Energy Materials and Solar Cells]

Study of Various Aspects of Phase Change Material During Solidification and Melting: A Review [pdf] [International Journal of Scientific Research in Science and Technology]

Development in Paraffin Based Thermal Storage System Through Shell and Tubes Heat Exchanger With Vertical Fins [ASME 2017 11th International Conference on Energy Sustainability]

Research roundup: HDPE spheres; erythritol-based composites; shape-stabilized PCM sheets; graphite foam; more

Ben Welter - Wednesday, August 23, 2017

High density polyethylene spheres with PCM for domestic hot water applications: Water tank and laboratory scale study [Journal of Energy Storage]

Numerical Simulation and Optimization of the Melting Process of Phase Change Material inside Horizontal Annulus [Energies]

Evaluation and comparison of erythritol-based composites with addition of expanded graphite and carbon nanotubes [Applied Energy]

Investigation of thermo-fluidic performance of phase change material slurry and energy transport characteristics [Applied Energy]

Numerical investigation of heat transfer performance of a rotating latent heat thermal energy storage [Applied Energy]

Application of shape-stabilized phase-change material sheets as thermal energy storage to reduce heating load in Japanese climate [Building and Environment]

Graphite foam as interpenetrating matrices for phase change paraffin wax: A candidate composite for low temperature thermal energy storage [Solar Energy Materials and Solar Cells]

Alkali polyphosphates as new potential materials for thermal energy storage [Solar Energy]

Magnesium phosphate cements formulated with low grade magnesium oxide incorporating phase change materials for thermal energy storage [Construction and Building Materials]

Numerical and experimental investigation of an insulation layer with phase change materials (PCMs) [Energy and Buildings]

Research roundup: Stearyl alcohol/ HDPE /expanded graphite composite PCM; perlite-based PCM wallboard; more

Ben Welter - Thursday, August 17, 2017

Improved thermal properties of stearyl alcohol/high density polyethylene/expanded graphite composite phase change materials for building thermal energy storage [Energy and Buildings]

Development and thermal performance of an expanded perlite-based phase change material wallboard for passive cooling in building [Energy and Buildings]

Numerical and experimental investigation of an insulation layer with phase change materials (PCMs) [Energy and Buildings]

Polyurethane foams with microencapsulated phase change material: Comparative analysis of thermal conductivity characterization approaches [Energy and Buildings]

Flammability assessment of Phase Change Material wall lining and insulation materials with different weight fractions [Energy and Buildings]

Thermal analysis of nanoparticle-enhanced phase change material solidification in a rectangular latent heat storage unit including natural convection [Energy and Buildings]

A portable solar-powered air-cooling system based on phase-change materials for a vehicle cabin [Energy Conversion and Management]

Thermal performance and economic evaluation of a newly developed phase change material for effective building encapsulation [Energy Conversion and Management]

Fabrication of three-dimensional metal-graphene network phase change composite for high thermal conductivity and suppressed subcooling phenomena [Energy Conversion and Management]

Researches of composite phase change material cooling/resistance wire preheating coupling system of a designed 18650-type battery module [Applied Thermal Engineering]

The impact of the heating/cooling rate on the thermoregulating properties of textile materials modified with PCM microcapsules [Applied Thermal Engineering]

Fatty acids/1-dodecanol binary eutectic phase change materials for low temperature solar thermal applications: Design, development and thermal analysis [Solar Energy]

An Experimental Evaluation of Direct Flow Evacuated Tube Solar Collector Integrated with Phase Change Material [Energy]

Heat capacities of some sugar alcohols as phase change materials for thermal energy storage applications [Journal of Chemical Thermodynamics]