Use of 3D printed concrete components for thermal energy storage

Effective thermal energy storage is key to expanding the use of thermal energy, which plays an important role in mitigating the energy crisis worldwide. Digital construction via additive manufacturing technology, has received an increasing interest over the past decades because it facilitates construction of geometrically complex objects at reduced construction time and cost compared to conventional construction techniques. This study combines these concepts and examines the suitability of concrete components 3D printed by selective binder activation and infused with phase change materials (PCM) for thermal energy storage applications. Immersion and vacuum impregnation techniques were used to incorporate organic and inorganic PCMs. The porosity, water and PCM absorption capacity, compressive strength, and microstructure of the 3D printed components were evaluated. The test results indicate that the base 3D printed concrete has a porosity of 41% which facilitates high PCM absorption. The absorption was most effective using vacuum assistance with the inorganic and organic volumetric absorptions reaching 39-45% and 34-40%, respectively. The compressive strength was impacted by the use of inorganic PCM. The microscopy results indicated delayed cement hydrate formation with minimal formation at early ages. The heat transfer provided by the infused PCM was shown to match expected latent and sensible heat transfer based on the thermal properties of the materials.