Session: 03-02 Phase Change Thermal Storage

Paper Number: 115258

115258 - Shape-Stable Wood-Phase Change Material Composite for Thermal Energy Storage in Buildings 

Maintaining thermal comfort in America’s buildings consumes 11% of the nation’s total energy use and emits 309 million metric tons of CO₂ in a single year. The energy efficiency of buildings can be improved by implementing phase change materials (PCMs) for thermal energy storage (TES). PCMs absorb and release significant amounts of heat upon changing phase within a narrow range of temperatures but require encapsulation to prevent leakage during melting. We fabricated a durable TES material using wood, a sustainable and microporous matrix, to encapsulate a PCM mixture of poly(ethylene glycol) (PEG) and poly(ethylene glycol) diacrylate (PEGDA). The wood-PCM composite demonstrates high thermal durability with consistent energy storage densities over 1000 thermal cycles and is remarkably shape-stable. Less than 5 wt % of the composite’s PCM is lost over a month of isothermal heating above 50 degrees C, thanks to the incorporation of a shape-stabilizing polymer, PEGDA. Additionally, we utilized a selective densification process on the wood matrix by subjecting the sample to controlled temperature and moisture gradients during compression. This process restores the reduced mechanical properties of the composite that result from the synthesis of the composite, namely delignification of the wood matrix for PCM incorporation. Our robust and shape-stable wood-PCM composite enables practical TES for building applications.

Presenting Author: Bernadette Magalindan The University of Texas at Dallas

Presenting Author Biography: Bernadette is a first-year PhD student in mechanical engineering at The University of Texas at Dallas. Her research focuses on sustainable energy storage technologies for buildings.