PI: Clay Naito and Muhannad Suleiman

Co-PI(s): Carlos Romero and Paolo Bocchini

University: Lehigh University

Thermal Energy Storage (TES) offers a critical solution to compensate for the intermittent nature of concentrating solar energy. Concrete and cementitious materials are promising candidates for sensible heat thermal energy storage at a large scale and a wide range of storage temperatures. One of the drawbacks of concrete is its inherent low energy storage density, which results in more required storage material, especially in systems that require large bulk energy storage. Integration of phase change material (PCM) within concrete is an innovative solution to address this shortcoming and make the storage system more efficient and compact. At Lehigh University, a team of faculty, researchers, and students are currently developing an energy storage system utilizing pervious concrete materials. The research integrates PCM into the pervious concrete material and utilizes the combined module to precool air used for temperature maintenance of energy cooling towers. The pervious concrete mixtures provide a means of creating cooling panels while maintaining structural resilience. The system performance can be enhanced by increasing the amount of PCM stored per volume in the panel and by improving the geometry to maximize surface area and heat exchange. In the proposed project, advances in 3D printing of concrete will be utilized to accomplish these improvements. An ongoing research effort by the PI has utilized binder jet technology to create 3D printed concrete components. The printing technique binds a cement and sand powder matrix using selective jetting of a water-based liquid. The natural concrete paste formation is used to create the structural matrix. The powder bed technique allows for negative draft and hollow geometries, allowing for an infinite array of panel configurations. The printed objects can be designed to have porous micro-structure, allowing for significant absorption of PCMs.