Optimal capacity configuration and dynamic operation of photovoltaic/thermal heat pump system with energy storage

A solar-driven energy system integrating photovoltaic/thermal (PV/T) collector and heat pumps is investigated to achieve further decarbonization and near-zero emissions in buildings. The capacity configuration and thermal-electrical dynamic operation characteristics for PV/T heat pump system are analyzed through multi-objective optimization. By transient heat current method, dynamic model is established for PV/T heat pump system, primarily powered by solar energy. Under the premise of satisfying user loads and enabling long-term system operation, multi-objective optimization framework is established for capacity configuration and analyzing the impact of PV/T collector quantity, heat source side tank capacity, user side tank capacity and compressor speed on energy, economic and environment performance. Critical thresholds were identified on study data context: PV/T collectors below 75 units show near-linear positive correlation with primary energy ratio and CO2 emission reduction rate, with diminishing returns beyond this point; heat source side tanks require exceeding 10 m3 for continuous operation, with performance gains plateauing above 13 m3; user side tanks exhibit strong cost sensitivity within variation from 2 to 8 m3. Lower compressor speed is optimal for energy-economic balance. Dynamic simulations demonstrated 82.4% domestic hot water demand coverage with 43.9% PV curtailment on optimal design point. The system operational characteristics are analyzed on supply gaps during low-irradiance and high-load demand peaks and suggested possible improvement recommendations. The optimization result emphasizes ensuring thermal energy storage capacity to mitigate solar periodic and intermittency, providing optimal configuration methodology for solar-dominated energy systems