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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 monthly PCM newsletter. Or join the discussion on LinkedIn.

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PCM battery shows promise in home heating system

Ben Welter - Tuesday, September 15, 2020

A home heating system equipped with a PCM battery put up encouraging numbers in a small trial in northern Italy earlier this year. The monthlong test “shows that is possible [for such a system] to supply the whole heating demand of a house reducing close to zero the costs,” says Domenico Feo, who developed the system. The full report, prepared by ThermaLink, a trademark of Sunservice Srl of Treviso, Italy, is available here.

ThermaCubeThe system is composed of a 6 kW solar array, an air/water heat pump and a thermal battery filled with BioPCM Q42, a biobased phase change material supplied by Phase Change Energy Solutions of Asheboro, N.C. A control unit, PCDCube, monitors temperatures and manages energy flow to optimize system performance. In an interview with Phase Change Matters, Feo answered questions about the heat battery, recently rebranded as ThermaCube.

Q: Thermal conductivity has proven to be a challenge in thermal energy storage across most types of PCM. Was conductivity an issue with the required charge/discharge cycles?

A: "As already known, the thermal conductivity of the PCM, especially of the organic one that we use, is low. This is, at the same time, a disadvantage and an advantage. The disadvantage has been minimized in using a heat exchanger made with a flat aluminum panel with the various layers just over 1 inch of distance; in this way we are able to make the entire volume of material work in a very efficient way. Vice versa this is an advantage for the very low heat losses during the non-work phases; in conditions of installations inside the buildings, the temperatures can be maintained for several days."

Q: If faster heat transfer is required, do you envision a redesign of the heat exchanger or a modification of the PCM to meet the demand of the energy transfer?

A: "As manufacturer, we can customize the heat exchanger dimensions and shape in order to achieve our goals, but as always in the industrial scalability, the quantities are mandatory for a good price. We designed a single heat exchanger dimension and multiply it in order to be able to produce the different storage capacities and realize a complete modular range. The transfer of energy can be however accelerated by increasing the flow rate of the fluid and the delta T between the fluid and the melting point, of course there is always a limit to this possibility. There are still studies around this point that need to be better understood."

Q: Would implementing several PCMs of different melting temperatures aid in the overall performance of the TES?

A: "Let's say that we expect a slight drop in performance at lower temperatures, but we don't have many other tests to give you a more general opinion."

Q: How is the PCM temperature measured throughout the entire storage to provide input to the PCDCube? Since the melting/solidification of PCM is not a homogenous process, are multiple measurements necessary to get a realistic status of the PCM?

A: "In the documents that we have published, we do not specify that we have installed two temperature probes, one in the center and another one near the walls and it is evident that, when the final phase of the  discharge of the PCM approaches, the perimeter probe shows a decrease of more sudden temperature than the central one. We, however, assume that the fact of having installed our thermal battery outside the building in a very cold climate, has exaggerated the heat loss despite the low heat transmission."

Q: Have you considered other PCM suppliers/products, since many are located in Europe and the RAL quality organization is based there?

A: "This is a possibility, at least for the distribution of our products in Europe and Asia. Currently we try to separate the supply of the case with exchangers (that we manufacture) from the PCM with direct purchase of the client from the supplier, especially in the larger units."

Q: What is the customer value proposition for this product? What is the expected return on investment/payback period?

A: "This is a $1 million question; the proposal is certainly into the growing wave of the storage market, even the electrical ones for PV systems. (A Tesla Powerwall is cool but not economically advantageous if you don’t pay attention at the payback that is higher than the life of the battery). The best value proposition is to separate production from the consumption of the energy and take advantage of renewable energies which, unfortunately, are linked to the day / night cycle and the outdoor temperature conditions. We see perfect the combination HP + Thermal Battery because we can concentrate the HP working hours during the best outdoor conditions that, for many reasons, are affecting and reducing the performances.  Furthermore, we also see a large market in the use of these thermal batteries in all these existing systems which are undersized or which, due to specific situations of changing use of the building, are no longer able to provide the necessary heating or cooling to the whole plant. About the ROI, this really varies a lot country by country because the cost of the electricity has different rates and peak hours schedules. The industrial needs are sometimes much more interesting and attractive than the residential ones."

Q: What are your plans for a commercial rollout?

A: "We are completing the Italian sales force and are looking for international distributors. Our goal is to propose the range of products at an international level with distribution agreements for the case only with exchangers; it will obviously be our responsibility to direct the partner to some reliable and high-quality PCM manufacturers. Obviously, those who will quickly give us the opportunity to build pilot plants, demonstrating the technology, will have an advantage in introducing them into the market and in the exclusivity of the contractual relationship."

PCM briefing: ThermoSafe-ACL Airshop agreement; new CEO at Phase Change Energy Solutions

Ben Welter - Sunday, September 06, 2020

Pegasus ULDSonoco ThermoSafe and ACL Airshop have announced a global agreementfor the handling and repair of ThermoSafe’s Pegasus ULD bulk temperature-controlled containers ACL Airshop, of Greenville, S.C., provides cargo support equipment and logistics solutions for airlines and air cargo carriers. Sonoco says the unit load device is made of composite materials that are lighter and more damage-resistant than traditional metal containers. It uses a gelled phase change material to maintain pharmaceutical-safe temperatures for five days or more, depending on the PCM used.

Has long-term thermal energy storage come of age? That's the premise of a recent advertorial sponsored by Viking Cold Solutions on Greentech Media's website. The Houston company says its PCM-based system, designed for use in cold storage facilities, stores enough energy to cycle off refrigeration for up to 13 hours per day and reduce energy consumption by more than 25 percent. Not much new in the article, but the reader comment section might be of interest to people who are familiar with the technology.

• A cycling club in Great Britain teamed up with Peli BioThermal this summer to deliver temperature-sensitive prescriptions to housebound people. The company supplied Banbury Star Cyclists with Crēdo ProMed temperature-controlled medical transport bags. The PCM-equipped bags are designed to transport pharmaceutical samples and medical supply payloads within two ranges, 2-8°C and 15-25°C.

Phase Change Energy Solutions of Asheboro, N.C., has a new chief executive officer. Govi Rao, co-founder and managing partner at CARBON Group Global, joined the company in April. His predecessor, Dennis McGill, had held the position since December 2018.

Sunamp Ltd. of Scotland has raised 4.5 million pounds in a Series A financing round led by Chilean venture capital firm Aurus Capital. Sunamp says it will use the funds to support commercial scaling in the United Kingdom and expansion in Central Europe, Asia and North America.

• The 15th Conference on Advanced Building Skins will be held as scheduled Oct. 26-27 in Bern, Switzerland. "In the unlikely event that the conference will not take place, or the participant may not be able to travel," organizers say, "paid registration will be credited to our conference next year." The 12 sessions, with over 70 presentations, will also be available online.

• A four-man canoe team put Glacier Tek's PCM-powered cooling vests to the test last month at the Missouri 340, a 340-mile paddle race from Kansas City to St. Charles, Mo. Team Mississippi, led by Scott Miller, 44, of Minneapolis, finished 11th overall in the race, completing the course in 44 hours, 38 minutes. The race drew more than 350 entries. Team members used the vests to cool down at checkpoints. Miller, second from left in the photo, plans to use the vests to battle the heat in the Great Alabama 650, which bills itself as the world's longest annual paddle race. That event begins Sept. 26 on the Coosa River in northern Alabama.

4-man canoe team will test Glacier Tek cooling vests in 340-mile race

Ben Welter - Sunday, August 02, 2020

A four-man canoe team will put Glacier Tek cooling vests to the test this week at the Missouri 340, a 340-mile paddle race from Kansas City to St. Charles, Mo.

Competitors have 88 hours to complete the Missouri River course. The race, first held in 2005, typically draws hundreds of canoeists and kayakers. The event record, set by a two-person canoe team in 2018, is 34 hours, 34 minutes.

Team Mississippi, led by Scott Miller, 44, of Minneapolis, will be paddling a 23-foot Wenonah Minnesota IV.

Scott Miller“The MR340 is usually held in July or August and is famous for being hot,” said Miller, right. “This year, however, the forecast looks shockingly mild, with highs in the upper 70s. We will be working hard, however, and expect to be in the bright sun much of the time and still generating plenty of body heat, so we anticipate the vests still being very useful during the sunniest and hottest times of the day.”

Glacier Tek cooling vests are designed to maintain a microclimate of 59 degrees F for up to 2.5 hours in 100 F heat. The cooling packs are powered by PureTemp, a phase change material certified as 100 percent biobased by the U.S. Department of Agriculture. The packs can be recharged in as little as 20 minutes in ice water. A support crew will supply Team Mississippi with fully charged packs as needed.

About the paddlers:

Rod Price, 60, of Winter Garden, Fla., has won approximately 300 canoe races in his 40 years of competition. He is the only paddler to complete North America's three longest distance races: the 1,200-mile Ultimate Florida Challenge (2012), the Yukon 1000-mile canoe race (2009) and the 750-mile Race to Alaska (2017). In 2019 Rod was selected for the Team USA Senior Dragon Boat Squad that competed in Thailand and won three gold medals. He has written three books about his racing adventures: “Racing to the Yukon” (2009), “Racing Around Florida” (2012) and “Have Paddle Will Travel” (2019).

How he copes with extreme heat: “Constantly hydrates with cold fluids containing electrolytes, wears light clothing and a sun hat and puts on sunscreen several times each day.

Oliver Simes, 27, of Cornucopia, Wis., has spent the last few years as a sea kayak guide in the Apostle Islands National Lakeshore. Paddled the length of the Mississippi River solo in a kayak in 2016.

How he copes with extreme heat:  “Keep ice in an insulated bottle. Going for swims.”

Bobby Johnson, 42, of Dunedin, Fla., has been been kayak racing for four years.

How he copes with extreme heat: “Depends on race. Clothing , hats, energy output. I run along shore under trees. Use the water I’m paddling on. Deal with it. Train hard.”

Scott Miller, 44, Minneapolis, Minn. In 2005, he paddled over 2,000 miles from Minneapolis to Hudson Bay (where the polar bears live), to celebrate the 75th anniversary of the trip taken by Eric Sevareid and Walter Port in 1930.

How he copes with extreme heat: “Dip hat or headband in water, hydrate before, during and after paddling, wear body-covering clothing to protect skin from the sun.”

About Glacier Tek

Glacier Tek LLC of Minneapolis, Minn., has been making high-tech garments that help defend the wearer from heat stress in extreme environments for more than 20 years. Glacier Tek’s first product, the Original Cool Vest, was among the earliest completely self-contained body cooling vests on the market. Our satisfied repeat customers include Dow Chemical, General Electric, General Mills, Kaiser Permanente and the FBI.

BioPreferred labelGlacier Tek cooling vests feature PureTemp phase change material, a biobased technology designed to absorb heat generated by the wearer. Glacier Tek vests maintain a comfortable 59 degrees for up to 2.5 hours, even in the most extreme heat, and never over-cool. Our vests offer better safety and cooling duration than that of evaporative, ice or gel-cooled vests.

Each Glacier Tek vest includes a set of cooling packs powered by PureTemp, a safe and effective biobased material. All Glacier Tek cooling packs have earned the USDA Certified BioPreferred® label, verification that the amount of renewable biobased material in the product meets or exceeds levels set by the U.S. Department of Agriculture.

INUTEQ donates hundreds of cooling vests to Dutch hospitals

Ben Welter - Monday, May 11, 2020

Hundreds of INUTEQ cooling vests developed for use by Dutch athletes at the Tokyo Olympics this summer have been donated for use in Dutch hospitals during the COVID-19 pandemic.

INUTEQ PCM pulloverThe PCM-equipped pullovers, designed to help athletes cope with heat stress, became available when the Tokyo Games were postponed until 2021. The pullovers can be worn under the heavy, heat-trapping protective gear used by doctors and nurses.

The pullovers are manufactured in Netherlands. The cooling material is Croda's CrodaTherm 21, a biobased PCM with a melting temperature of 21 degrees C. The 1.3-kg pullover is a simple "one-size-fits-most" garment, with two adjustable buckles and no fabric shell. 

“Doctors and nurses at the ICU, who are treating corona patients, can work comfortably for up to three hours longer thanks to this cooling vest," said Dr. Thijs Eijsvogels, physiologist at Radboud University Medical Center, Nijmegen. "The cooling vests ensure a stable body temperature, less sweating, maintenance of concentration and a faster recovery after each intensive work session.”

The pullover is marketed as "PCM CoolOver" on the INUTEQ website. It can be worn "under military combat gear, hazardous materials suits, mascot costumes and other professional apparel."   

https://inuteq.com/pcm-coolover-medical-nl/pcm-coolover-medical-eng/

Phase Energy announces a new shape-stable PCM

Ben Welter - Monday, May 11, 2020

Phase Energy Ltd. has announced the development of shape-stable technology for organic wax-based PCMs.

The company, based in Hull, United Kingdom, said a tetradecane-based shape-stable material would typically contain more than 90% PCM; the new technology has achieved levels of up to 96%. "Initial tests indicate that little, if any, enthalpy is lost, possibly due to the very low level of additives required," the company said.

The technology was jointly developed with Rainer Busch of IBC Europe, Germany.

"So far, the technology has been used for paraffins, esters etc. and on a range of PCMs with [melt points] of up to 53 degrees Centigrade," Phase Energy said in a LinkedIn post. "The technology permits the production of leak-resistant packs/pouches using very simple process technology." 

"We’re currently working with some companies in the cold chain area; looking at cold packs/pouches, pallet covers etc.," Ian Biggin, director at Phase Energy, said in an e-mail. "As the technology can be adapted to higher temperature PCMs we are also interested in those areas as well but we decided that cold chain was the obvious place to start."

The photo below illustrates the material's flexibility. According to the company, it "shows a shape stable sample, 100 x 30 x 12mm, containing 92% tetradecane and 8% additives, being stretched to >700mm. When released the sample returned to its original size."

http://phase-energy.com/new-shape-stable-pcm-development/

PCM briefing: EnergyNest is finalist for startup award; Croda website offers live chat

Ben Welter - Tuesday, March 24, 2020

EnergyNest is one of 15 start-ups nominated as finalists of the Start Up Energy Transition Award 2020. EnergyNest's thermal battery consists of steel cassettes with pipes encased in a special type of concrete. The Norwegian company announced earlier this year that an EnergyNest battery with a capacity of 6-8 MWh would be installed at a brick manufacturing plant in Austria.

• "T-History Simplified: Combining a Universal Standard with an IoT Strategy," presented by Madison Hammerberg, product development engineering manager at CAVU Group, will be among the presentations at the Advancements in Thermal Management conference in Denver, Aug. 6-7, 2020.

Croda now offers live chat on its CrodaTherm website, www.crodatherm.com. The "Chat with a Croda Expert" feature is designed to provide visitors with "instant support."

Terrafore Technologies of Minneapolis is one of 13 companies to be awarded a Launch Minnesota Innovation Grant from the state's Department of Employment and Economic Development. The grants total $344,000; the amounts of individual grants were not disclosed. Terrafore is developing thermal energy storage to provide dispatchable solar power generation to the grid.

RayGen Resources Pty. Ltd. of Australia has been awarded $3 million AUD toward a feasibility study for a 4 MW “solar hydro” power plant in Victoria. The money will come from the Australian Renewable Energy Agency. RayGen's system extracts heat from solar panels and stores it in a water reservoir acting as a heat store. The hot reservoir is paired with cold reservoir chilled by electricity from the solar panels and the grid. The temperature difference powers an Organic Rankine Cycle engine to generate electricity with a round-trip efficiency of 70%.

• The Swedish thermal energy storage company Azelio has completed the installation of "a system that will store solar energy from what is claimed to be the world’s largest concentrated solar power plant project," Energy Storage Journal reports. "The complex [in Morocco] is 2,500 hectares in size, and solar panels cover 1,000 square metres — which means it could potentially harvest a total of 2.6GW a year." The system uses recycled aluminum as the heat storage material.

Sunamp Ltd. of Edinburgh, Scotland, has signed a memo of understanding with Ripple Energy, a company that enables customers to part-own large-scale wind farms to power their homes. Under the agreement, Ripple will offer its customers Sunamp heat batteries, which use a specially formulated phase change material to store large amounts of energy from renewable and other sources and release it as heat to deliver hot water and space heating as needed.

Cubesat propulsion concept wins $225,000 National Science Foundation grant

Ben Welter - Friday, February 14, 2020

A Cubesat propulsion system that uses phase change material to store solar thermal energy for use when needed has been awarded a $225,000 National Science Foundation SBIR grant. The ThermaSat concept, developed by Howe Industries of Tempe, Ariz., is designed to provide propulsion for a typical 15kg cubcubesat for 10 years.

Cubesats are tiny satellites — weighing as little as 200 grams — that orbit close to Earth’s atmosphere. They are cheaper to develop and launch than larger satellites. Cubesats have a wide range of purposes, including the collection of mapping and weather data. More than 1,100 have been successfully deployed.

Troy Howe, owner of Howe Industries, answered questions about the ThermaSat propulsion system.

Q: How long has your company been working on the concept?

A: "We have been working on this topic for only about a year in preparation for our NSF proposal, but have experience with optical systems and phase change materials going back about five years."

Q: Can you briefly describe how the system works?

A: "The ThermaSat works by heating liquid water propellant to high temperature steam using incident sunlight. Normally, it is difficult to reach high enough temperatures to use water as propellant, but our optical filtration system is designed to reject long wavelengths of light and only transmit short wavelengths- similar to the greenhouse effect. The phase change materials in the thermal capacitor store the solar energy over a period of hours and then heat the propellant during a 'burn' phase.

ThermaSat cutaway drawing"The PCM will be distributed throughout a graphite matrix in the form of small beads. Flow channels will run axially down the length of the cylinder for the propellant to pass through. The design is based loosely on the old NERVA fuel elements from the nuclear rocket program in the 1970s, with the UC kernels being replaced with our PCM. The drawing here shows a cutaway of the thermal capacitor surrounded by the optical system.

"The system is very conceptual at this point and has not been tested, although the propulsion characteristics are well understood. Our task at this point is to show that the optical system works as predicted and can reach the desired temperatures. Phase II will address the effects of a vacuum environment on a prototype."

Q: What type of PCM is used?

A: "We chose a salt (80LiOH+20LiF) as our PCM, it melts at 700K and has a latent heat of fusion of 1163 J/g. The material was selected based on a study performed by NASA in 1986 on space energy storage. The paper was called 'Technology for Brayton-Cycle Space Powerplants Using Solar and Nuclear Energy' by Robert English.""

Q: How much PCM would be used in a system powering a typical Cubesat?

A: "The standard design includes 0.62 kg of PCM. "

Q: Are you working with any Cubesat manufacturers at this point?

A: "We received letters of interest from Pumpkin Space Systems, Aster Labs, and Arizona State University. They all expressed interest in having a safe and reliable Cubesat propulsion system but we have not formally formed collaboration with any manufacturers at this point.”

Q: How will you use the NSF SBIR grant?

A: "Our goals for this topic include demonstrating the optical system in a lab bench test, fabricating photonic crystals, and performing computational analysis on the thermal, structural, and propulsion systems."

Q: What's the next major step in commercializing the system?

A: "Our commercialization strategy right now is to build a functioning prototype and demonstrate operation on earth. From that point we will aim to do a flight test which performs a set of orbital maneuvers and successfully de-orbits itself. From there we will work with Cubesat manufacturers to move forward."

Q: What excites you most about this project?

A: "We are excited about how near term and effective this technology will be for the upcoming Cubesat revolution. We hope to provide a safe, reliable, and effective propulsion solution that can be used with thousands of different satellites and drastically increase the performance of new technologies in space in the timeframe of just a few years.”

PCM briefing: Ice Energy files for bankruptcy; Viking Cold has opening for thermal engineer

Ben Welter - Monday, February 10, 2020

Ice Energy, the Santa Barbara, Calif., company that made and distributed ice-based thermal energy storage systems, has filed for bankruptcy. The company's Ice Bear system makes ice at night when demand for electricity is low and capacity is abundant. During the day, the stored ice is used to provide cooling. Details of the Chapter 7 bankruptcy, filed in December, are sparse. The company's website is no longer active. Over the years, Ice Energy had won several major energy storage and distribution contracts with utilities, and had begun marketing a smaller version of the Ice Bear system aimed at retail customers. 

Viking Cold Solutions has an opening for a chemical/thermal engineer in Houston. The engineer will "conduct research in Thermal Science, Storage/Heat Transfer and Phase Change Materials (PCM) for low temperature applications (<10⁰C)."

Axiom Exergy has secured more than $1 million in orders for the Axiom Cloud, a software platform that helps manage energy consumption in supermarkets and cold storage facilities that use the company's PCM-powered thermal storage systems.

• The 2020 Advancements in Thermal Management conference, to be held Aug. 6-7 in Denver, has issued a call for presentations. Topics include thermal materials, thermal modeling and characterization and measurement of thermal materials. Abstracts are due Feb. 12.

EnergyNest will install a large thermal energy storage battery at a Senftenbacher brick factory in Austria. The system will temporarily store excess energy in the form of hot air from a tunnel furnace. The stored heat be converted to steam and later reused in production.

Devan Chemicals, the Belgium-based developer of finishing technologies for textiles, introduced its Tones of Cool Bio technology at the Heimtextil trade show in Frankfurt, Germany, last month. The technology "stimulates the textile to dissipate redundant heat from the body and to instantly reduce the body temperature," the company says. The phase change materials "are derived from sustainable, natural sources.

Registration is open for the 23rd Microencapsulation Industrial Convention to be held June 8-11 in Rotterdam, Netherlands.

PCM newsletter marks 5th anniversary

Ben Welter - Tuesday, January 14, 2020

The Phase Change Matters newsletter is celebrating its fifth anniversary with the publication of issue No. 224. Only a handful of folks received issue No. 1; the first issue of 2020 was e-mailed to 1,303 subscribers. More than 40,000 people from more than 160 countries visited puretemp.com last year. Here are the most-viewed newsletter posts from 2019:

1. PureTemp introduces temperature-control fabric coating (Jan. 23)

2. New dorm at Massachusetts college features 18,000+ square feet of PCM mats (Aug. 15)

3. Croda began work on new microencapsulated PCM four years ago (July 26)

4. PCM-equipped infant warming mat set for large-scale trial in Rwanda (Jan. 7)

5. Novel PCM microspheres keep new therapy pack flexible when frozen (June 15)

6. Croda adds 2 biobased phase change materials to its lineup (May 17)

7. PCM system inefficiencies blamed on design flaws, operator errors (March 25)

8. Sunamp signs agreement with Chinese heat pump maker (March 18)

9. PureTemp shows energy-saving potential in EnergyPlus simulations (Aug. 28)

10. Microtek introduces new PCM built with nextek encapsulation technology (March 11)

Sunamp's UniQ heat storage product earns RAL certification

Ben Welter - Monday, December 16, 2019

The RAL Quality Association PCM has awarded the RAL Quality Mark to Sunamp Ltd. for its UniQ line of thermal batteries.

RAL quality markThe product, which has been installed in thousands of homes across Europe, uses a specially formulated phase change material to store large amounts of energy from renewable and other sources and release it as heat to deliver hot water and space heating as needed. The PCM is sodium acetate trihydrate-based with a patented formulation giving a melt point of 58 degrees Celsius. 

In independent testing conducted by ZAE Bayern, the PCM was successfully melted and solidified in a UniQ heat battery for 10,000 cycles. At the end of the test, no significant differences in stored thermal energy capacity were found between the cycled samples and an uncycled sample of the PCM. The product, which also passed leak testing, earned the association's highest level of certification, Grade A. 

Over 3,000 UniQ units are now in service, with Sunamp projecting a tenfold growth in sales next year. The quality mark will be featured on Sunamp’s website and in other marketing materials, UniQ manuals and product labels.

“We are delighted that our thermally charged UniQ product range of heat batteries has been awarded a globally recognized mark of quality,” said Kate Fisher, Ph.D., a materials integration scientist at Sunamp, which is based in Edinburgh, Scotland. “RAL certification is a huge accolade and cements Sunamp’s position as world leaders at the forefront of the technology.”

Sunamp UniQ heat batteriesThe RAL Quality Association PCM was established in 2004 to develop standards for the PCM industry. Members include Axiotherm, Microtek Laboratories, Rubitherm, Croda Europe, va-Q-tec, PCM Technology, Global-Systems Europe, Sasol, Sunamp, Pluss Advanced Technologies and PureTemp LLC.

Members and non-members alike can submit their products to the association for independent testing and earn the RAL Quality Mark. To qualify for the mark, products and materials must meet standards for energy storage capacity and phase transition temperature and stability, as defined in RAL-GZ 896.

“I am delighted that more and more products with PCM technology can be awarded the RAL Quality Mark as meaningful and transparent proof of quality and longevity,” said Stefan Thomann, the association’s managing director. “The great thing about Sunamp´s UniQ heat batteries is that they can be installed and used in homes very easily and save a lot of energy costs and carbon emissions immediately. The fact that they passed more than 10,000 cycles make sure that users will be able to profit from these benefits for decades.”