Energy and exergy analysis of solar energy enhanced two-stage compression heat pump system

Abstract

Abstract: In order to improve the performance of the heat pump system, a solar energy enhanced two-stage compression heat pump system (SETHP) is proposed. A thermodynamic model of the system is established. The system performance under different working conditions is analyzed, which compared with the traditional two-stage compression heat pump system (TSHP). The results indicate that the coefficient of heating performance COP_h and exergy efficiency first increase and then decrease with the increase of the intermediate temperature. As the condensation temperature increases, COPh decreases and exergy efficiency increases. As the evaporation temperature increases and solar irradiance increases, COP_h and exergy efficiency both increase. Compared with the TSHP system, the performance of the SETHP system is significantly improved. The research of SETHP system can provide new ideas and methods for the application of solar heat pump heating technology in low temperature environment.

Key words: solar energy, two-stage compression, heat pump, energy analysis, exergy analysis

CLC Number:

TK519

SHI Jia-meng, LI Feng-lei. Energy and exergy analysis of solar energy enhanced two-stage compression heat pump system[J]. Journal of Lanzhou University of Technology, 2023, 49(2): 41-48.

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