Demonstration Performance Evaluation of an Air-Based PVT-Assisted Air-Source Heat Pump System

Photovoltaic thermal systems are capable of simultaneously generating electricity and recovering thermal energy from the rear surface of photovoltaic modules. When integrated with an air-source heat pump, the thermal energy recovered from an air-based photovoltaic thermal system can be utilized as an auxiliary heat source, thereby improving heating performance and reducing electricity consumption. In this study, a demonstration-scale performance assessment of an air-based photovoltaic thermal-assisted air-source heat pump system was conducted in a real building located in Asan, South Korea. Performance analysis was based on measured operational data collected over a one-month period in March 2024, corresponding to late-winter to early-spring conditions when heating demand was still present. During the measurement period, the average plane-of-array solar irradiance was approximately 600 W/m2, with peak values reaching up to 1000 W/m2. Under these conditions, the air-based photovoltaic thermal collector provided average electrical and thermal power outputs of 1.96 kW and 2.2 kW, respectively, while peak outputs reached 3.3 kW for electricity generation and 3.8 kW for thermal energy recovery. The daily thermal energy production remained relatively stable, ranging from 17.8 to 21.7 kWh. Furthermore, approximately 45–60% of the recovered thermal energy was effectively transferred to a buffer tank through an air-to-water heat exchanger, indicating stable solar heat recovery and storage performance. When the recovered thermal energy was supplied to the air-source heat pump during daytime heating operation, a preheating effect was observed, resulting in reduced electricity consumption and improved heating performance. The coefficient of performance increased from 2.24 during nighttime operation to 2.81 under solar-assisted daytime conditions, corresponding to a notable reduction in electricity consumption under solar-assisted daytime operation, compared with nighttime operation without PVT preheating. Overall, the results indicate that, under the tested late-winter to early-spring heating conditions, the integrated air-based photovoltaic thermal and air-source heat pump system can enhance heating performance and reduce electricity consumption, demonstrating its practical feasibility as a solar-assisted heating solution rather than representing generalized annual performance.