A compact modular microchannel membrane-based absorption thermal energy storage system for highly efficient solar cooling

This study applies the microchannel membrane-based module to develop a novel modular and compact thermal energy storage system to meet building requirements with solar or waste thermal energy in a low-carbon path. Compared to traditional systems, the novel system demonstrates significant improvements, with the charging and discharging rates increased by 2 and 3 times. The energy storage efficiency is enhanced from 0.470 to 0.772, while energy storage density based on fluid and setup volume are increased by 78.62% and 120.90% respectively. The charging/discharging rate and solution concentration glide increase continuously as the heat source temperature rises from 75 °C to 100 °C, leading to continuous increases in energy storage density and efficiency. As increasing channel length, width, number, and module number, or decreasing channel height improves the charging/discharging rate. Energy storage density can be enhanced by augmenting the channel height and width, increasing the quantity of both channels and modules, or diminishing the channel length. Conversely, smaller channel dimensions and larger channel heights are advantageous for higher efficiency. The scaling up combined with customizability, and popularization of the proposed compact modular microchannel membrane-based absorption thermal energy storage system would be required for mass uptake of this innovative solution in building cooling applications.