Study on the Dynamic Performance of Solar Space Heating System with Seasonal Thermal Energy Storage

The main problems restricting the development of solar heating systems are the low energy density and instability of solar energy. The problems of seasonal mismatch between energy supply with demand and the instability can be solved effectively, through the application of seasonal thermal energy storage technology in the solar space heating system. In this paper, a solar district heating system model (basically composed of a solar collector’s array, a seasonal thermal energy storage, a buffer tank, an auxiliary natural gas-fired boiler and controllers) has been established based on the dynamic simulations platform TRNSYS. The variation law of the key parameters and dynamic operation characteristics of the system are obtained, which provides an important reference for the popularization and application of solar space heating system with seasonal thermal energy storage. And the solar fraction of the system can be reached as much as 96.7 % with the low temperature district heating technology.