CH-24-C053 - Application of Salt Hydrate-Based Thermochemical Energy Storage in Buildings

Thermochemical energy storage utilizing salt hydrates is a novel method to harness renewable and low-grade thermal energy. Notable benefits of this mechanism encompass a higher energy storage capacity per unit volume and minimal energy loss, especially for long-term storage. In this study, we developed a hybrid heating system that combines the benefits of thermochemical energy storage (using SrCl2) and renewable energy (solar power) for space heating and/or domestic water heating. To validate the system, we conducted numerical simulations in the TRNSYS environment, focusing on a single-family house located in Atlanta. Specifically, the system utilizes solar thermal collectors to capture thermal energy and then transfers the heat collected to a tank filled with salt, which acts as the thermochemical energy storage element in the system. During periods of abundant sunlight, this system absorbs and stores heat in the tank, which can later be used during nights. The storage tank can serve as a supplemental heating source for the building studied and thus minimize the usage of the primary heating device, e.g., a conventional gas-fired furnace, thus minimizing energy consumption. This study also demonstrates the superiority of using salt for heat storage to systems employing water as the storage medium. Water-based storage requires a larger tank volume to achieve the same heat storage capability, compared with salt-based storage. Through the implementation and advancement of this novel heating system, our study aims to contribute to sustainable building operations and foster a greener future by reducing carbon footprint. A consequential reduction in energy consumption may also translate to substantial long-term cost savings. Therefore, the deployment of this technology could be an economically and environmentally advantageous venture.