Progress and challenges in the integration of solar heat pumps with thermal collectors and PCM-based thermal energy storage systems for heating applications

Abstract

One of the most popular and promising approaches to reaching carbon neutrality and global carbon peaking is the solar-assisted heat pump system (SAHP), which offers the benefits of low carbon dioxide (CO₂) emissions and great energy efficiency. The performance of an energy-efficient heat pump (HP) can be significantly enhanced by integrating it with a solar thermal collector (STC) and phase change material (PCM) that has substantial heat storage densities. Consequently, there has been a lot of interest in heat pump systems coupled with thermal collectors and PCM-based thermal energy storage (TES) systems. This research offers a comprehensive and up-to-date synthesis of current developments in designing, advancing, and application of SAHPs in combination with solar thermal collectors (STCs) and phase change material (PCM) systems. This study also focuses on the solar thermal energy storage applications of PCM encapsulation for SAHP systems and highlights their ability to improve heat storage system efficiency and the process of defrosting. It is clear from a thorough review of advanced technologies in these fields that SAHP -TES- STC is a promising pathway to efficient and low-emission heating for residential, commercial, and industrial applications. Moreover, the techno-economic evaluation of solar thermal collectors and PCM-based energy storage technology with HP systems is discussed and shows that they are efficient and sustainable, yet full adoption depends on further cost and performance improvement. The current study findings suggest a need for developing efficient thermal collectors, integrating AI-based smart control technologies, and high-performance advanced PCMs with better thermal conductivity and stability. Furthermore, maximizing system performance for different climates, especially in colder places, is critical to ensuring year-round operation. In the end, the problems together, their solutions, and potential future study areas are also addressed, which contributes to advancing sustainable heating technologies for residential and industrial applications.