TY  - EJOU
AU  - Li, Haogen 
AU  - Ma, Guangbai 
AU  - Xu, Haiying 
AU  - Zheng, Shumei 
AU  - Geng, Zhe 
AU  - Zhang, Shuzhen 
AU  - He, Suoying 
AU  - Gao, Ming 
AU  - Ali, Muzaffar 
AU  - Chaudhary, Ghulam Qadir 

TI  - A Review of Recent Advances in the Application of Solar-Air Source Heat Pump Systems
T2  - Energy Engineering

PY  - 
VL  - 
IS  - 
SN  - 1546-0118

AB  - Solar-air source heat pump (SAHP) systems integrate solar thermal or photovoltaic resources with air-source heat pumps (ASHPs) to support low-carbon building heating. This integration can reduce solar intermittency and mitigate ASHP performance degradation in cold climates by raising the evaporating temperature, improving renewable-energy self-consumption, and stabilizing heat supply. However, current SAHP deployment is still constrained by rigid control logic, frosting and compressor stress under extreme cold conditions, high initial investment, and inconsistent performance evaluation across studies. To address these issues, this review systematically summarizes recent advances in SAHP architectures, including direct-expansion SAHP (DX-SAHP), indirect-expansion SAHP (IDX-SAHP), photovoltaic-coupled SAHP (PV-SAHP), photovoltaic/thermal-coupled SAHP (PV/T-SAHP), and building-integrated photovoltaic/thermal SAHP (BIPV/T-SAHP). A standardized comparison framework is introduced using COP, SPF, solar fraction, energy-saving rate, exergy efficiency, economic indicators, carbon-emission reduction, system complexity, and climate adaptability. The review further discusses supporting technologies such as thermal storage, active thermal management, vapor injection, model predictive control, reinforcement learning, BEMS integration, and photovoltaic-energy storage-direct current-flexibility (PEDF) systems. The findings indicate that SAHP systems can become core energy units for green buildings only when thermodynamic optimization, intelligent control, cost reduction, and architectural integration are developed together.
KW  - Solar thermal; solar photovoltaic; air source heat pump; heating system; building decarbonization

DO  - 10.32604/ee.2026.086013