Heat pump integrated with latent heat energy storage

Abstract

Large-scale thermal energy storage is currently an effective technology to address the intermittency of renewable energy power, shift terminal peak power load, and match energy supply and demand. Nevertheless, the quality and quantity of thermal energy will decrease due to irreversible losses in thermodynamic processes during heat storage and utilization, resulting in the inability to achieve the same amount of energy input and output. Integrating heat pumps with high-efficiency latent heat thermal energy storage systems with phase change materials (PCMs) can increase the heat temperature and heat quantity, enabling flexible heat regulation and cascade utilization. The key issue of adaptability between the two in the case of a mismatch between heat load and demand has not been given sufficient attention. We first introduce the significance and bilateral advantages of integrating heat pumps and latent heat storage systems. An overview of the integration systems is then presented, including the components, integration types, integration principles, etc. In particular, the strategies for improving the integration system performance from a latent heat storage perspective are presented. Finally, the state-of-the-art of integration systems is systematically summarized on the basis of different heat pumps, and the challenges and perspectives on the integration systems for future development are discussed.