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 monthly PCM newsletter. Or join the discussion on LinkedIn.




Austin's NexusHaus features rainwater thermal storage system

Ben Welter - Friday, March 20, 2015

Austin EcoNetwork says an 850-square-foot solar-powered house under development in Austin demonstrates the "creative thinking" needed to address the Texas city's limited access to local food, high energy demands, strained water resources and urban sprawl. NexusHaus, a collaboration of the University of Texas, the Technical University of Munich and the city of Austin, is designed to be an affordable solution. Features include "an integrated rainwater thermal storage system" that will shift cooling to off-peak hours and help cut energy consumption by about 80 percent during peak hours.

Modular 'Aktivhaus' produces no emissions or waste, derives no energy from fossil fuel

Ben Welter - Wednesday, March 18, 2015

Aktivhaus modular home in Stuttgart, Germany

Architect/engineer Werner Sobek's latest creation, a prototype of a modular home that generates twice as much energy as it uses, is featured in a CNN piece this week. The 900-square-foot Aktivhaus dwelling in Stuttgart, Germany, can be assembled in a single day. It is designed to produce no emissions or waste and derive no energy from fossil fuel, a standard that Sobek refers to as "Triple Zero." The house is packed with energy-efficient features, including a rooftop solar system that produces electricity and heat, and a thermal-regulation system linked to an underground ice storage tank.

"In summer, the ice is used to cool the house. By melting, it absorbs heat energy," Sobek says. "In winter, it gradually freezes. Each time a chunk of water turns into ice, a certain amount of heat energy is released, which is then used to heat the house via a heat pump, which brings the energy to a higher temperature level."

Inside Federal Center South, an ASHRAE award-winning project

Ben Welter - Wednesday, February 11, 2015

Tom Boysen Jr.In December, a U.S. Army Corps of Engineers office building in Seattle was one of nine projects recognized for innovative design with an ASHRAE Technology Award. Federal Center South received first place in the new commercial buildings category. 

The Seattle Daily Journal of Commerce takes a closer look at the project, including the months of tweaking needed to reach the energy-use guarantees made by the general contractor, Sellen Construction.

“This is not your father's 1960s pickup truck,” said Tom Boysen, senior project manager. “This thing has at least four gears of cooling and two gears of heating.”

The complex system includes heat-recovery chillers that extract heat from a thermal storage tank to warm the building in the morning, when demand is high. The rooftop tank is filled with 2-foot-long panels containing phase change material that freezes and thaws at 55 degrees, serving as a battery for storing heat.

Research roundup: Polyurethane embedded graphite; gypsum board; nanoparticle PCM slurry; more

Ben Welter - Monday, February 09, 2015

  • Electro/photo to heat conversion system based on polyurethane embedded graphite [Applied Energy]

  • Thermal evaluation of laminated composite phase change material gypsum board under dynamic conditions [Renewable Energy]

  • Different energy balances for the redesign of nearly net zero energy buildings: An Italian case study [Renewable and Sustainable Energy Reviews]

  • Experimental study on the influence of nanoparticle PCM slurry for high temperature on convective heat transfer and energetic performance in a circular tube under imposed heat flux [Applied Thermal Engineering]

  • Mortars based in different binders with incorporation of phase-change materials: Physical and mechanical properties [European Journal of Environmental and Civil Engineering]

  • A new approach to theoretical modeling of heat transfer through fibrous layers incorporated with microcapsules of phase change materials [Thermochimica Acta]
  • IRENA to launch 'Google of renewable energy'

    Ben Welter - Tuesday, January 13, 2015

    CleanTechnica's Zachary Shahan reports that the International Renewable Energy Agency is ready to unveil REsource, a research tool he describes as "akin to a Google of renewable energy." 

    IRENA says the goal is to provide "relevant, reliable and timely information on renewable energy market statistics, potentials, policies, finance, technology costs and benefits, innovations and education."  Screenshots of the tool show a Google-like main screen that will allow visitors to tap IRENA's "vast knowledge base" for information by source, energy type and country.  

    The tool is expected to be launched at IRENA's 5th Assembly in Abu Dhabi next week.

    10 strategies for sustainable lab design

    Ben Welter - Tuesday, January 06, 2015

    Blake Jackson and Stephen Palumbo of Tsoi/Kobus and Associates and Jacob Knowles of BR+A Consulting Engineers offer "10 practical strategies to help guide decision-making to further elevate sustainable laboratory design, regarding resource utilization, carbon footprint and long-term viability." Strategy No. 1: Reduce lighting power densities. The authors note that building codes are lowering LPD thresholds, thanks to the availability of cheaper and more energy-efficient LEDs for ambient and task lighting.