Thermodynamic analysis of absorption energy storage cycle with choline based green solvents

The absorption refrigeration and heat pump system and the thermochemical energy storage technology have natural and easy combination characteristics. The working pairs store and release low-grade heat in the form of thermochemical energy by changing the concentration of the solution, which can realize thermal or cold storage. This paper uses three deep eutectic solvents of choline chloride as absorbents and water as the refrigerant. The working fluid pair has a competitive or higher performance, ignoring the power consumption caused by flow resistance. The influence of generation or charging temperature on refrigeration performance and energy storage density were theoretically studied. The results show that water/Ethaline performs best under a typical single-effect working condition in cycle heat storage ratio and energy storage density, up to 0.87 and 677.8 kJ/kg; Glyceline and Reline have a better application potential when driven temperatures increase.

Automated summary

This paper explores the combination characteristics of absorption refrigeration and heat pump system with thermochemical energy storage technology. By using three deep eutectic solvents and water as working fluids, the refrigeration performance and energy storage density under different conditions were studied theoretically. The results show that water/Ethaline performs the best under a typical single-effect condition, while Glyceline and Reline have better application potential with increasing driving temperatures.