On the cusp of a new year, we are proud to present the 100th issue of Phase Change Matters, a weekly summary of the latest news and research on phase change materials and thermal energy storage. To subscribe, visit www.puretemp.com/subscribe. For more frequent updates, follow @puretemp on Twitter or visit the Phase Change Matters blog, www.puretemp.com/pcmatters. Here’s wishing you and yours a happy and fulfilling 2017!
Colorado’s first certified International Passive House is nestled in the foothills of the Rocky Mountains north of Denver. The 1,200-square-foot MARTaK house, designed by architect and author Andrew Michler, is used primarily as an off-the-grid workspace. The structure has now been occupied continuously for six months. Has it met Michler’s energy expectations?
“Yes,” Michler says, “it’s gone well past my expectations. … We haven’t turned on the heating system this year.”
A solar array shared with a neighboring home provides all electrical power and most of the heating, with a propane-powered hydronic system serving as backup. Passive House Planning Package software was used to find the most efficient mix of insulation, windows and shading. Natural, nontoxic and recycled materials are used throughout the house.
Biobased phase change material with a melt point of 23º C is used to help even out temperature spikes. The PCM is contained in 500 square feet of ENRG Blankets made by Phase Change Energy Solutions. Most of the material is installed a south-facing interior wall.
Is it possible to measure the PCM’s impact on overall performance?
“That’s the question that I haven’t found anybody able to answer,” Michler says. “It’s more about experiential. It’s hard to isolate the PCM performance. There’s no good modeling software for this. …
“Overheating has been the biggest issue with passive houses, and we’re seeing some anecdotal success with PCMs. We had a really warm fall, and the PCM did seem to level out the interior temperature, leveling out at 78 degrees Fahrenheit.”
Has Michler used PCM in other projects? “No, this is the first. I do have interest in trying it again.”
U.S. patent application 20160380279 (applicant The Boeing Co., Chicago, Ill.):
“A heat transfer system includes a fuel cell module that produces heat and water, and a thermal energy storage module that stores the heat produced by the fuel cell module. The thermal energy storage module includes a phase-change material. A conduit couples the fuel cell module to the thermal energy storage module. The conduit is oriented to channel the water produced by the fuel cell module through the thermal energy storage module.”
U.S. patent application 20160374847 (applicant Hill-Rom Services Inc., Batesville, Ind.):
“A protective dressing includes an outer dressing and an adhesive layer. The outer dressing includes an opening and a cavity sized to receive a phase-change material (PCM) insert (1408) inserted through the opening. The adhesive layer is configured to adhere to a patient’s skin surrounding an anatomic site. When adhered to the patient’s skin, the PCM insert modifies the patient’s skin at the anatomic site. The PCM insert may be removed and replaced with another PCM insert. For example, a warm PCM insert may be replaced with a refrigerated PCM insert. The opening of the outer dressing may be self-sealing. The opening of the outer dressing may be sealed with an upper layer dressing coupled to the PCM cooling insert.”
YEAR IN REVIEW
Here are the most-viewed Phase Change Matters posts of 2016:
Entropy Solutions’ website, puretemp.com, drew visitors from more than 150 countries in 2016. Each dot on this map represents a city that generated one or more visits:
• An experimental PCM heat exchanger has been installed aboard the International Space Station. The device is designed to help maintain safe temperatures for crew members and equipment. It uses a water-based PCM to remove heat from areas that must be cooled and move it into areas that must be warmed.
• China News Service reports that Asia’s first molten salt solar power plant has been connected to the grid and will begin operations next week in northwestern China. The 10-megawatt plant, run by Beijing Shouhang Resources Saving Co., generates electricity from solar power 24 hours a day. It will provide electricity for 30,000 households during its initial phase.
• A cooling technology that can operate without a constant power supply will undergo pilot trials in Dubai. Sure Chill‘s water-based system is used in a refrigerator that maintains a temperature range of 2° to 8° C for 10 days or more without the need for a grid-based electricity. The Welsh company signed a memo of understanding with the state-run Dubai Electricity and Water Authority after taking part in the 12-week Dubai Future Accelerators Program.
• In a decision involving a patent on phase change material, a U.S. appeals court has reversed a Patent Trial and Appeal Board decision to exclude certain e-mails used as evidence of an earlier conception date in REG Synthetic Fuels LLC v. Neste Oil OYJ. The court found that the board had improperly excluded the emails as hearsay.
• Noting recent acquisitions by FedEx and UPS, Pelican Biothermal VP Kevin Lawler lists consolidation among the key trends likely to shape the temperature-controlled logistics market in 2017.
For our full list of recent academic research, see puretemp.com/academic. Here are highlights from the past week:From Applied Thermal Engineering:
• Experimental and comprehensive theoretical study of cold storage packages containing PCM
From Energy and Buildings:
• Application of Phase Change Materials in Gypsum Boards to Meet Building Energy Conservation Goals
• Experimental and Numerical Investigation of the Cross-flow PCM Heat Exchanger for the Energy Saving of Building HVAC
From Applied Energy:
• Experimental and numerical investigation of discharging process of direct contact thermal energy storage for use in conventional air-conditioning systems
• Experimental and numerical study of thin ring and annular fin effects on improving the ice formation in ice-on-coil thermal storage systems
• Experimental characterization and simulation of a hybrid sensible-latent heat storage
From Energy Procedia:
• Thermal and Fluid Characteristics of a Latent Heat Thermal Energy Storage Unit
• Numerical Modeling of Thermal Performance of Active-passive Ventilation Wall with Phase Change Material
From Acta Montanistica Slovaca:
• Development of heat storage unit based on the phase change materials for mining machinery with combustion engines
From Procedia Manufacturing:
• Experimental Study of the Performance of Phase Change Material Air Cooling Rig
From International Refrigeration and Air Conditioning Conference:
• Transient multiphysics modeling of a robotic personal air-conditioning device
• Design and Performance of Thermal Energy Storage Module using High Thermal Conductivity Phase Change Composite Material
From Journal of Thermal Analysis and Calorimetry:
• Characterization of paraffin/ultrasonic-treated diatomite for use as phase change material in thermal energy storage of buildings
From Sustainable Cities and Society:
• Evaluation of Ice Thermal Energy Storage (ITES) for commercial buildings in cities in Brazil
From Fluid Phase Equilibria:
• Experimental and in silico characterization of xylitol as seasonal heat storage material
From Energy Conversion and Management:
• Thermal characteristics of expanded perlite/paraffin composite phase change material with enhanced thermal conductivity using carbon nanotubes
More than 980 of your peers have joined a LinkedIn group devoted to the discussion of phase change material and thermal energy storage. The Phase Change Matters group is an interactive complement to the award-winning blog and newsletter of the same name.
You are invited to join the group and connect with PCM and TES experts from around the world. New members include Antonio F. Ros Marín, technical coordinator, Métodos Servicios Agrícolas S.L., Spain; Holger Böhme, research assistant at Technische Universität Chemnitz, Germany; and Michael Molnar, director of business development, Melior Innovations, Houston, Texas.