Energy Storage Science and Technology ›› 2024, Vol. 13 ›› Issue (2): 669-676.doi: 10.19799/j.cnki.2095-4239.2023.0698

• Energy Storage System and Engineering • Previous Articles     Next Articles

Application of phase change heat storage in heat pump heating system based on time-of-use electricity pricing

Jinxiang YU1,2(), Yibo WANG2, Jianhong GUO2(), Xiaoyu ZHANG1   

  1. 1.School of Electrical and Information Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
    2.Institute of Electrical Engineering of the Chinese Academy of Sciences, Beijing 100190, China
  • Received:2023-10-10 Revised:2023-10-23 Online:2024-02-28 Published:2024-03-01
  • Contact: Jianhong GUO E-mail:yujinxiang@mail.iee.ac.cn;guojh@mail.iee.ac.cn

Abstract:

China has proposed the goal of carbon peak and carbon neutrality to promote the utilization of renewable energy and electrification of heating. Reducing the costs of electric heating has become an urgent need. This study presents a novel heat pump heating system with phase change heat storage. The system charges during surplus renewable energy generation or off-peak electricity and discharges during intermittent periods of renewable energy or peak electricity, achieving thermoelectric decoupling and peak shaving. Owing to the flexibility in utilizing phase change heat storage devices, control strategies can be dynamically adjusted based on the characteristics of renewable energy generation or peak and off-peak electricity periods. This study analyzes the operational performance of the system primarily driven by off-peak electricity and examines the influences of different thermal storage times and capacities on the economy of the system. Experiments were conducted in the high-altitude region of Qinghai. The system with phase change heat storage reduces costs by 5.28% compared to heat pump direct heating. By adjusting control strategies to change the charging time with a storage capacity of 75 kWh, power consumption and operating costs of the system can be reduced by 5.69% and 13.5%, respectively. Increasing the storage capacity to 150 kWh can adjust the peak and off-peak electricity consumption, with the proportion of off-peak electricity reaching a maximum of 84.52%. This further reduces operating costs by 10.04%. The heating system with phase change heat storage demonstrates good economic benefits. The rational utilization of its thermoelectric decoupling characteristics can contribute to the absorption of renewable energy and the stable operation of the power grid.

Key words: phase change heat storage, heat pump, heating system, economy

CLC Number: