Innovative Phase Change Materials for Thermal Energy Storage

Lev Ovadia, HUJI, Faculty of Science, The Institute of Chemistry


  • Solar thermal collectors convert 60 - 80% of the incident solar radiation into heat, which can then be used to generate steam or heated water for industrial processes, for heating of buildings or to supply hot water. Low pressure steam is appealing, since it does not require high pressure tanks, tubes and fittings. However, steam is consumed by the industry 24 hours every day, whereas solar light is available only at day time. In addition, steam has very low density, low volumetric energy and its storage is, thus, impractical.
  • Phase change materials (PCM) are of great interest as they can serve as energy storage carriers, and bridge between solar irradiation time and energy consumption periods, thus provide the ability for renewable (reusable) energy, which may be used in versatile industries.
  • The present available PCMs do not possess the properties required for usage in the different applications, as they present drawbacks, such as, inappropriate phase change temperature, inappropriate latent heat, poor thermal reversibility, high hysteresis, low durability, disintegrates with phase change cycles, unstable and corrosive.

Our Innovation

A novel family of PCM material with improved characteristics for energy storage usage.

  • Allows intraday energy storage and uninterrupted desiccant regeneration in the absence of solar radiation
  • Cheap and small footprint solution
  • Improved stability (e.g., non-corrosive, non-explosive) and low flammability.
  • Non-toxic material


  • Composite of organic and inorganic entities
  • The composite exhibits a phase change temperature near the target temperature, high latent heat, high thermal and material reversibility, low hysteresis, and stability.
  • Further functionalities include no (or low) phase segregation or no (or low) material disintegration upon melting-crystallization cycle and repeated cycles, no (or low) material degradation at exposure to high temperature for prolonged time, low vapor pressure, high thermal conductivity and small volume changes on phase transition


  • Hospitals, chemical and biological laboratories, nursing home and electronic clean rooms where desiccant dehumidification and low relative humidity becomes important and external ventilation is required for pathogen and toxicity control.
  • Supermarkets and retail stores, office buildings, hotels and restaurants that require high external ventilation rate due to their routine activity.
  • Low-rise residential buildings
  • Green buildings
  • Sustainable construction technologies

Contact for more information:

Matt Zarek
Contact ME: